Document:

Trust Supplement No. 2015-1B

 Exhibit 4.3 

EXECUTION VERSION 
 TRUST
SUPPLEMENT NO. 2015-1B 
 Dated as of August 11, 2015 

between 
 SPIRIT AIRLINES, INC.

 and 
 WILMINGTON
TRUST, NATIONAL ASSOCIATION, 
 as Trustee, 

To 
 PASS THROUGH TRUST
AGREEMENT 
 Dated as of August 11, 2015 

Spirit Airlines Pass Through Trust 2015-1B 

Spirit Airlines Pass Through Certificates, 

Series 2015-1B 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 Table of Contents 

 

							
	 	 	 	  	Page	 
		
	 Article I DEFINITIONS
	  	 	2	  
	 Section 1.01
	 	 Definitions
	  	 	2	  
		
	 Article II DECLARATION OF TRUST
	  	 	8	  
	 Section 2.01
	 	 Declaration of Trust
	  	 	8	  
	 Section 2.02
	 	 Permitted Activities
	  	 	8	  
		
	 Article III THE CERTIFICATES
	  	 	8	  
	 Section 3.01
	 	 The Certificates
	  	 	8	  
	 Section 3.02
	 	 Terms and Conditions
	  	 	8	  
		
	 Article IV ISSUANCE AND TRANSFER OF THE CLASS B CERTIFICATES
	  	 	10	  
	 Section 4.01
	 	 Issuance of Class B Certificates
	  	 	10	  
	 Section 4.02
	 	 Legends
	  	 	10	  
	 Section 4.03
	 	 Book-Entry Provisions for Global Certificates
	  	 	11	  
		
	 Article V DISTRIBUTION; STATEMENTS TO CERTIFICATEHOLDERS
	  	 	12	  
	 Section 5.01
	 	 Statements to Certificateholders
	  	 	12	  
		
	 Article VI DEFAULT
	  	 	14	  
	 Section 6.01
	 	 Purchase Rights of Certificateholders
	  	 	14	  
		
	 Article VII THE TRUSTEE
	  	 	16	  
	 Section 7.01
	 	 Delivery of Documents; Delivery Dates
	  	 	16	  
	 Section 7.02
	 	 Withdrawal of Deposits
	  	 	17	  
	 Section 7.03
	 	 The Trustee
	  	 	18	  
	 Section 7.04
	 	 Representations and Warranties of the Trustee
	  	 	18	  
	 Section 7.05
	 	 Trustee Liens
	  	 	19	  
		
	 Article VIII ADDITIONAL AMENDMENT; SUPPLEMENTAL AGREEMENTS
	  	 	19	  
	 Section 8.01
	 	 Amendment of Sections 5.02, 6.07, 7.09, 8.04, 9.01, 12.01 and 12.02 of the Basic Agreement
	  	 	19	  
	 Section 8.02
	 	 Supplemental Agreements Without Consent of Class B Certificateholders
	  	 	19	  
	 Section 8.03
	 	 Supplemental Agreements with Consent of Class B Certificateholders
	  	 	20	  
	 Section 8.04
	 	 Consent of Trustees for Amendment of Section 6.01
	  	 	20	  
		
	 Article IX MISCELLANEOUS PROVISIONS
	  	 	21	  
	 Section 9.01
	 	 Final Termination Date
	  	 	21	  
	 Section 9.02
	 	 Basic Agreement Ratified
	  	 	21	  
	 Section 9.03
	 	 Governing Law
	  	 	21	  
	 Section 9.04
	 	 Counterparts
	  	 	21	  
	 Section 9.05
	 	 Intention of Parties
	  	 	21	  
	 Section 9.06
	 	 Submission to Jurisdiction
	  	 	21	  
	 Section 9.07
	 	 Successor and Assigns
	  	 	22	  
	 Section 9.08
	 	 Normal Commercial Relations
	  	 	22	  
	 Section 9.09
	 	 No Recourse against Others
	  	 	22	  
	  
 EXHIBITS

 
	  			
	Exhibit A	 	-     Form of Certificate	  			
	Exhibit B	 	-     DTC Letter of Representations	  			
	Exhibit C	 	-     Amendments to Basic Agreement	  			

  

					
		  	i	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

					
	 SCHEDULES
  
	  	
	Schedule I	 	-     Series B Equipment Notes, Principal Amounts, Maturities and Aircraft	  	
	 Schedule II
	 	 -     Note Documents
	  	

  

					
		  	(ii)	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 TRUST SUPPLEMENT NO. 2015-1B 

This TRUST SUPPLEMENT NO. 2015-1B, dated as of August 11, 2015 (as amended from time to time, the “Trust Supplement”),
between SPIRIT AIRLINES, INC., a Delaware corporation (together with any successor in interest pursuant to Section 5.02 of the Basic Agreement, the “Company” or “Spirit”), and WILMINGTON TRUST, NATIONAL ASSOCIATION, a
national banking association, as trustee (together with any successor in interest and any successor or other trustee appointed as provided in the Basic Agreement, the “Trustee”) under the Pass Through Trust Agreement, dated as of
August 11, 2015, between the Company and Wilmington Trust, National Association (the “Basic Agreement”). 
 W I T N E S S E
T H: 
 WHEREAS, the Basic Agreement, which is unlimited as to the aggregate face amount of Certificates that may be issued and
authenticated thereunder, has heretofore been executed and delivered; 
 WHEREAS, Spirit has obtained commitments from Airbus S.A.S. for the
delivery scheduled on or prior to December 31, 2016 of the 15 aircraft described in Schedule I (the “Aircraft”), and Spirit wishes to finance the Aircraft pursuant to the NPA; 

WHEREAS, pursuant to each Indenture, Spirit will issue on a recourse basis two series of Equipment Notes secured by the related Aircraft and
may issue one or more series of Additional Equipment Notes and one or more series of Refinancing Equipment Notes; 
 WHEREAS, the Trustee
shall hereby declare the creation of the Class B Trust (as defined below) for the benefit of Holders of the Class B Certificates (as defined below) to be issued in respect of such Class B Trust, and the initial Holders of the Class B Certificates,
as grantors of such Class B Trust, by their respective acceptances of the Class B Certificates, shall join in the creation of the Class B Trust with the Trustee; 

WHEREAS, all Certificates to be issued by the Class B Trust will evidence Fractional Undivided Interests in the Class B Trust and will have no
rights, benefits or interests in respect of any other separate Trust or the property held therein; 
 WHEREAS, the Escrow Agent and the
Underwriters have contemporaneously herewith entered into an Escrow Agreement with the Escrow Paying Agent pursuant to which the Underwriters will deliver to the Escrow Agent the proceeds from the sale of the Class B Certificates, and have
irrevocably instructed the Escrow Agent to withdraw and pay funds from such proceeds upon request and proper certification by the Trustee to purchase Series B Equipment Notes pursuant to the NPA and the applicable Participation Agreements from time
to time prior to the Delivery Period Termination Date; 
 WHEREAS, the Escrow Agent on behalf of the Class B Certificateholders has
contemporaneously herewith entered into a Deposit Agreement with the Depositary under which the Deposits referred to therein will be made and from which Deposits it will withdraw funds to allow the Trustee to purchase Series B Equipment Notes from
time to time prior to the Delivery Period Termination Date; 
 WHEREAS, pursuant to the terms and conditions of the Basic Agreement, as
supplemented by this Trust Supplement, the NPA and the Participation Agreements, the Trustee on behalf of the Class B Trust shall from time to time purchase the Series B Equipment Notes issued by the Company pursuant to the Indentures related to the
Aircraft having the identical interest rate as, and final maturity dates not later than the final Regular Distribution Date of, the Class B Certificates issued hereunder and shall hold such Series B Equipment Notes in trust for the benefit of the
Class B Certificateholders; 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 WHEREAS, pursuant to the terms and conditions of the Intercreditor Agreement referred to in
Section 3.02(i) hereof, the Trustee and the other parties thereto will agree to the terms of subordination set forth therein; 

WHEREAS, all of the conditions and requirements necessary to make this Trust Supplement, when duly executed and delivered, a valid, binding
and legal instrument in accordance with its terms and for the purposes herein expressed, have been done, performed and fulfilled, and the execution and delivery of this Trust Supplement in the form and with the terms hereof have been in all respects
duly authorized; 
 WHEREAS, the Basic Agreement, as supplemented by this Trust Supplement, is subject to the provisions of the Trust
Indenture Act and shall, to the extent applicable, be governed by such provisions; 
 NOW, THEREFORE, in consideration of the mutual
agreements herein contained, and of other good and valuable consideration the receipt and adequacy of which are hereby acknowledged, the parties hereto agree as follows: 

ARTICLE I 
 DEFINITIONS

 Section 1.01 Definitions. Unless otherwise specified herein or the context otherwise requires, capitalized terms used but
not defined herein, including in the recitals hereto, shall have the respective meanings set forth, and shall be construed and interpreted in the manner described, in the Basic Agreement. As used herein, the term “Agreement” shall mean the
Basic Agreement, as supplemented by this Trust Supplement. For all purposes of the Basic Agreement as supplemented by this Trust Supplement, the following capitalized terms have the following meanings (any term used herein which is defined in both
this Trust Supplement and the Basic Agreement shall have the meaning assigned thereto in this Trust Supplement for purposes of the Basic Agreement as supplemented by this Trust Supplement). 

Account: Has the meaning ascribed thereto in the Deposit Agreement. 

Additional Certificateholder: Has the meaning specified in the Intercreditor Agreement. 

Additional Certificates: Has the meaning specified in the Intercreditor Agreement. 

Additional Equipment Notes: Has the meaning specified in the Intercreditor Agreement. 

Additional Trust: Has the meaning specified in the Intercreditor Agreement. 

Additional Trust Agreement: Has the meaning specified in the Intercreditor Agreement. 

Affiliate: Has the meaning specified in the Intercreditor Agreement. 

Agreement: Has the meaning specified in the first paragraph of Section 1.01 of this Trust Supplement. 

Aircraft: Has the meaning specified in the recitals to this Trust Supplement and any Replacement Aircraft (as defined in
the applicable Indenture) in replacement thereof in accordance with the applicable Indenture. 
 Applicable Funding
Date: Has the meaning specified in Section 7.01(b) of this Trust Supplement. 

  

					
		  	2	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 Applicable Notice of Purchase Withdrawal: Has the meaning specified in the
Escrow Agreement. 
 Applicable Participation Agreement: Has the meaning specified in Section 7.01(b) of this
Trust Supplement. 
 Basic Agreement: Has the meaning specified in the preamble to this Trust Supplement. 

Business Day: Has the meaning specified in the Intercreditor Agreement. 

Certificate: Means a Class A Certificate or a Class B Certificate, as applicable. 

Certificate Buy-Out Event: Has the meaning specified in the Intercreditor Agreement. 

Certificateholder: Means, with respect to any Class of Certificates, the Person in whose name a Certificate is
registered in the Register for the Certificates of such Class. 
 Class: Has the meaning specified in the
Intercreditor Agreement. 
 Class A Certificateholder: Means, at any time, any Certificateholder of one or more
Class A Certificates. 
 Class A Certificates: Has the meaning specified in the Intercreditor Agreement.

 Class A Trust: Has the meaning specified in the Intercreditor Agreement. 

Class A Trust Agreement: Has the meaning specified in the Intercreditor Agreement. 

Class A Trustee: Has the meaning specified in the Intercreditor Agreement. 

Class B Certificateholder: Means, at any time, any Certificateholder of one or more Class B Certificates. 

Class B Certificates: Has the meaning specified in Section 3.01 of this Trust Supplement. 

Class B Liquidity Facility: Has the meaning specified in the Intercreditor Agreement. 

Class B Liquidity Provider: Has the meaning specified in the Intercreditor Agreement. 

Class B Trust: Has the meaning specified in Section 2.01 of this Trust Supplement. 

Code: Means the Internal Revenue Code of 1986, as amended. 

Company: Has the meaning specified in the preamble to this Trust Supplement. 

Corporate Trust Office: Has the meaning specified in the Intercreditor Agreement. 

Cut-off Date: Has the meaning specified in Section 3.02(b) of this Trust Supplement. 

Definitive Certificates: Has the meaning specified in Section 4.01(e) of this Trust Supplement. 

Delivery Period Termination Date: Has the meaning specified in the NPA. 

Deposit Agreement: Means, subject to Section 5 of the NPA, the Deposit Agreement (Class B), dated as of the date
hereof, relating to the Class B Certificates between the Depositary and the Escrow Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms. 

  

					
		  	3	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 Depositary: Means, subject to Section 5 of the NPA, Natixis, a French
société anonyme, acting via its New York Branch. 
 Deposits: Has the meaning specified in the Deposit
Agreement. 
 Distribution Date: Means a Regular Distribution Date or a Special Distribution Date. 

DTC: Has the meaning specified in Section 3.02(f) of this Trust Supplement. 

DTC Participants: Has the meaning specified in Section 4.01(b) of this Trust Supplement. 

Equipment Notes: Has the meaning specified in the Intercreditor Agreement. 

ERISA: Means the Employee Retirement Income Security Act of 1974, as amended. 

Escrow Agent: Means, initially, Wilmington Trust Company, a Delaware trust company, and any replacement or successor
therefor appointed in accordance with the Escrow Agreement. 
 Escrow Agreement: Means the Escrow and Paying Agent
Agreement (Class B), dated as of the date hereof, relating to the Class B Certificates, among the Escrow Agent, the Escrow Paying Agent, the Trustee and the Underwriters, as the same may be amended, supplemented or otherwise modified from time to
time in accordance with its terms. 
 Escrow Paying Agent: Means the “Paying Agent” as defined in the Escrow
Agreement. 
 Escrow Period Termination Date: Has the meaning specified in Section 5.01(c)(i) of this Trust
Supplement. 
 Escrow Receipt: Means a receipt substantially in the form annexed to the Escrow Agreement representing
a fractional undivided interest in the funds held in escrow thereunder. 
 Event of Default: With respect to any
Indenture, has the meaning specified in Section 4.01 of such Indenture. 
 Final Withdrawal: Has the meaning
specified in the Escrow Agreement. 
 Final Withdrawal Date: Has the meaning specified in the Escrow Agreement. 

Fractional Undivided Interests: Has the meaning specified in the Intercreditor Agreement. 

Funding Date: Has the meaning specified in the NPA. 

Funding Notice: Has the meaning specified in the NPA. 

Global Certificate: Has the meaning specified in Section 4.01(b) of this Trust Supplement. 

Holder: Means a Certificateholder. 

Indenture: Has the meaning specified in the Intercreditor Agreement. 

Indenture Event of Default: Means, with respect to any Indenture, any Event of Default (as such term is defined in such
Indenture). 

  

					
		  	4	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 Indirect Participants: Has the meaning specified in Section 4.01(b)
of this Trust Supplement. 
 Intercreditor Agreement: Has the meaning specified in Section 3.02(i) of this Trust
Supplement. 
 Issuance Date: Has the meaning specified in Section 7.01(a) of this Trust Supplement. 

Junior Additional Certificateholder: Means, with respect to any Additional Certificateholder exercising its right to
purchase Certificates under Section 6.01 of this Trust Supplement, any holder of any class of Additional Certificates that rank junior, in priority of payment of “Expected Distributions” for such class under the Intercreditor
Agreement, to the class of Additional Certificates held by such Additional Certificateholder. 
 Liquidity Provider:
Has the meaning specified in the Intercreditor Agreement. 
 Loan Trustee: Means, with respect to any Indenture, the
bank, trust company or other financial institution designated as loan trustee thereunder, and any successor to such loan trustee. 

Note Documents: Means, collectively, the Participation Agreements, the Indentures, each Indenture Supplement (as defined
in any Indenture), each Manufacturer’s Consent (as defined in any Indenture) and the Equipment Notes. 
 Notice of
Purchase Withdrawal: Has the meaning specified in the Deposit Agreement. 
 NPA: Means the Note Purchase
Agreement, dated as of the date hereof, among the Trustee, the Class A Trustee, the Company, the Escrow Agent, the Escrow Paying Agent and the Subordination Agent, providing for, among other things, the purchase of Series B Equipment Notes by
the Trustee on behalf of the Class B Trust, as the same may be amended, supplemented or otherwise modified from time to time, in accordance with its terms. 

Operative Agreements: Has the meaning specified in the Intercreditor Agreement. 

Other Agreements: Means (i) the Class A Trust Agreement, (ii) any Additional Trust Agreement and
(iii) any Refinancing Trust Agreement. 
 Other Trustees: Means the trustees under the Other Agreements, and any
successor or other trustee appointed as provided therein. 
 Other Trusts: Means the Class A Trust, any
Additional Trust or Trusts, or any Refinancing Trust or Trusts, in each case created by the applicable Other Agreement. 

Participation Agreement: Has the meaning specified in the Intercreditor Agreement. 

Paying Agent: Means, with respect to the Class B Certificates, the paying agent maintained and appointed for such Class
B Certificates pursuant to Section 7.12 of the Basic Agreement. 
 Person: Means any individual, corporation,
limited liability company, partnership, joint venture, association, joint-stock company, trust, trustee, unincorporated organization or government or any agency or political subdivision thereof. 

Plan: Means (i) a retirement plan or other employee benefit plan or arrangement, including for this purpose an
individual retirement account, annuity or Keogh plan, that is subject to Title I of ERISA or Section 4975 of the Code, (ii) any other entity whose underlying assets are 

  

					
		  	5	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 
deemed to include the assets of any plan or arrangement described in (i) above by virtue of the U.S. Department of Labor regulation in 29 CFR §2510.3-101, as modified by
Section 3(42) of ERISA (or any successor to such regulation), or (iii) such a plan or arrangement which is a foreign, church or governmental plan or arrangement exempt from Title I of ERISA and Section 4975 of the Code but subject to
a Similar Law. 
 Pool Balance: Means, as of any date, (i) the original aggregate face amount of the Class B
Certificates less (ii) the aggregate amount of all distributions made as of such date in respect of the Class B Certificates or in respect of Deposits other than distributions made in respect of interest or Premium or reimbursement of any costs
or expenses incurred in connection therewith. The Pool Balance as of any date shall be computed after giving effect to any distribution with respect to unused Deposits, the payment of principal, if any, of the Series B Equipment Notes or payment
with respect to other Trust Property and the distribution thereof to be made on such date. 
 Pool Factor: Means, as
of any Distribution Date, the quotient (rounded to the seventh decimal place) computed by dividing (i) the Pool Balance by (ii) the original aggregate face amount of the Class B Certificates. The Pool Factor as of any Distribution Date
shall be computed after giving effect to any distribution with respect to unused Deposits, payment of principal, if any, of the Series B Equipment Notes or payment with respect to other Trust Property and the distribution thereof to be made on that
date. 
 Premium: Has the meaning specified in the Intercreditor Agreement. 

Prospectus Supplement: Means the final prospectus supplement, dated July 28, 2015, relating to the offering of the
Certificates. 
 PTC Event of Default: Has the meaning specified in the Intercreditor Agreement. 

Rating Agencies: Has the meaning specified in the Intercreditor Agreement. 

Refinancing Certificateholder: Has the meaning specified in the Intercreditor Agreement. 

Refinancing Certificates: Has the meaning specified in the Intercreditor Agreement. 

Refinancing Equipment Notes: Has the meaning specified in the Intercreditor Agreement. 

Refinancing Trust: Has the meaning specified in the Intercreditor Agreement. 

Refinancing Trust Agreement: Has the meaning specified in the Intercreditor Agreement. 

Regular Distribution Date: Has the meaning specified in Section 3.02(c) of this Trust Supplement. 

Replacement Deposit Agreement: Has the meaning specified in the NPA. 

Replacement Depositary: Has the meaning specified in the NPA. 

Replacement Liquidity Facility: Has the meaning specified in the Intercreditor Agreement. 

Replacement Liquidity Provider: Has the meaning specified in the Intercreditor Agreement. 

Responsible Officer: Has the meaning specified in the Intercreditor Agreement. 

  

					
		  	6	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 Scheduled Payment: Has the meaning specified in the Intercreditor
Agreement. 
 Securities Act: Means the Securities Act of 1933, as amended. 

Series B Equipment Notes: Has the meaning specified in the Intercreditor Agreement. 

Similar Law: Means a foreign, federal, state, or local law which is substantially similar to the prohibited transaction
provisions of Title I of ERISA or Section 4975 of the Code. 
 Special Distribution Date: Means, with respect to
the Class B Certificates, each date on which a Special Payment is to be distributed as specified in this Agreement. 

Special Payment: Means any payment (other than a Scheduled Payment) in respect of, or any proceeds of, any Equipment
Note or the Collateral (as defined in any Indenture). 
 Special Payments Account: Means, with respect to the Class B
Certificates, the account or accounts created and maintained for such series pursuant to Section 4.01(b) of the Basic Agreement (as modified by Section 7.01(c) of this Trust Supplement) and this Trust Supplement. 

Spirit: Has the meaning specified in the preamble to this Trust Supplement. 

Subordination Agent: Has the meaning specified in the Intercreditor Agreement. 

Triggering Event: Has the meaning specified in the Intercreditor Agreement. 

Trust: Means the Class A Trust or the Class B Trust, as applicable. 

Trust Indenture Act: Means the Trust Indenture Act of 1939, as amended. 

Trust Property: Means (i) subject to the Intercreditor Agreement, the Series B Equipment Notes held as the property
of the Class B Trust, all monies at any time paid thereon and all monies due and to become due thereunder, (ii) funds from time to time deposited in the Certificate Account and the Special Payments Account and, subject to the Intercreditor
Agreement, any proceeds from the sale by the Trustee pursuant to Article VI of the Basic Agreement of any Equipment Notes and (iii) all rights of the Class B Trust and the Trustee, on behalf of the Class B Trust, under the Intercreditor
Agreement, the Escrow Agreement, the NPA and the Class B Liquidity Facility, including, without limitation, all rights to receive certain payments thereunder, and all monies paid to the Trustee on behalf of the Class B Trust pursuant to the
Intercreditor Agreement or the Class B Liquidity Facility, provided that rights with respect to the Deposits or under the Escrow Agreement, except for the right to direct withdrawals for the purchase of Series B Equipment Notes to be held
herein, will not constitute Trust Property. 
 Trust Supplement: Has the meaning specified in the preamble hereto.

 Trustee: Has the meaning specified in the preamble to this Trust Supplement. 

Underwriters: Means Citigroup Global Markets, Inc., Morgan Stanley & Co. LLC and Credit Suisse Securities (USA)
LLC. 
 Underwriting Agreement: Means the Underwriting Agreement, dated July 28, 2015, among the Underwriters and
the Company, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms. 

Withdrawal Certificate: Has the meaning specified in the Escrow Agreement. 

  

					
		  	7	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 ARTICLE II 

DECLARATION OF TRUST 

Section 2.01 Declaration of Trust. The Trustee hereby declares the creation of a Trust, designated the “Spirit Airlines Pass
Through Trust 2015-1B” (the “Class B Trust”), for the benefit of the Holders of the Class B Certificates to be issued in respect of such Class B Trust, and the initial Holders of the Class B Certificates, as grantors of such Class B
Trust, by their respective acceptances of the Class B Certificates, join in the creation of such Class B Trust with the Trustee. The Trustee, by the execution and delivery of this Trust Supplement, acknowledges its acceptance of all right, title and
interest in and to the Trust Property to be acquired pursuant to Section 7.01(b) of this Trust Supplement, the NPA and the Participation Agreements and the Trustee will hold such right, title and interest for the benefit of all present and
future Holders of the Class B Certificates, upon the trusts set forth in the Basic Agreement and this Trust Supplement. The provisions of this Section 2.01 supersede and replace the provisions of Sections 2.03 of the Basic Agreement, with
respect to the Class B Trust. 
 Section 2.02 Permitted Activities. The Class B Trust may only engage in the transactions
contemplated by the Operative Agreements, subject to Section 9.05 of this Trust Supplement. 
 ARTICLE III 

THE CERTIFICATES 

Section 3.01 The Certificates. There is hereby created a series of Certificates to be issued under this Agreement designated as
“Spirit Airlines Pass Through Certificates, Series 2015-1B” (the “Class B Certificates”). Each Class B Certificate represents a Fractional Undivided Interest in the Class B Trust created hereby. The Class B Certificates
shall be the only instruments evidencing a Fractional Undivided Interest in the Class B Trust. The Class B Certificates do not represent indebtedness of the Class B Trust, and references herein to interest accruing on the Class B Certificates are
included for purposes of computation only. 
 Section 3.02 Terms and Conditions. The terms and conditions applicable to the
Class B Certificates and the Class B Trust are as follows: 
 (a) The aggregate face amount of the Class B Certificates that may be
authenticated and delivered under this Agreement (except for Class B Certificates authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Class B Certificates pursuant to Sections 3.03, 3.04, 3.05
and 3.06 of the Basic Agreement and Section 4.03 of this Trust Supplement) is $120,959,000. 
 (b) The “Cut-off Date” is the
earlier of (i) the day after the Delivery Period Termination Date, and (ii) the date on which a Triggering Event occurs. 
 (c)
The distribution dates with respect to any payment of Scheduled Payments (each such distribution date, a “Regular Distribution Date”) shall be April 1 and October 1 of each year, commencing on April 1, 2016, until payment of
all of the Scheduled Payments to be made under the Equipment Notes has been made; provided, however, that, if any such day shall not be a Business Day, the related distribution shall be made on the next succeeding Business Day without
additional interest. The principal amount of the Series B Equipment Notes to be held by the Class B Trust is scheduled for payment on April 1 and October 1 in certain years, commencing on October 1, 2016 and ending on the applicable
date specified under the heading “Maturity” on Schedule I with respect to the related Aircraft, as set out in Schedule III to the NPA. 

  

					
		  	8	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 (d) The Special Distribution Date with respect to the Class B Certificates means any Business Day
on which a Special Payment is to be distributed pursuant to this Agreement. 
 (e) At the Escrow Agent’s request under the Escrow
Agreement, the Trustee shall affix the corresponding Escrow Receipt to each Class B Certificate. In any event, any transfer or exchange of any Class B Certificate shall also effect a transfer or exchange of the related Escrow Receipt. Prior to the
Final Withdrawal Date, no transfer or exchange of any Class B Certificate shall be permitted unless the corresponding Escrow Receipt is attached thereto and also is so transferred or exchanged. By acceptance of any Class B Certificate to which an
Escrow Receipt is attached, each holder of such a Class B Certificate acknowledges and accepts the restrictions on transfer of the Escrow Receipt as set forth herein, in such Escrow Receipt, and in the Escrow Agreement. 

(f) The Class B Certificates shall be in the form attached hereto as Exhibit A, shall be Book-Entry Certificates (subject to
Section 3.05(d) of the Basic Agreement and Section 4.03 of this Trust Supplement), and shall be subject to the conditions set forth in the Letter of Representations between the Class B Trust and The Depository Trust Company and any
successor agency thereto (“DTC”), as initial Clearing Agency, attached hereto as Exhibit B. 
 (g) The proceeds of the offering of
Class B Certificates issued by the Class B Trust and related Escrow Receipts shall be deposited in the Accounts and shall be used in accordance with the Escrow Agreement, the Deposit Agreement and the NPA to acquire from time to time the Series B
Equipment Notes described in Schedule I that relate to the Aircraft and to the Note Documents described in Schedule II. 
 (h) Any
Person acquiring or accepting a Class B Certificate or an interest therein will, by such acquisition or acceptance, be deemed to (i) represent and warrant to the Company, the Loan Trustees and the Trustee that either (1) no assets of a
Plan or any trust established with respect to a Plan have been used to purchase or hold Class B Certificates or an interest therein or (2) the purchase and holding of Class B Certificates or interests therein by such Person are exempt from the
prohibited transaction restrictions of ERISA and the Code or provisions of Similar Law pursuant to one or more prohibited transaction statutory or administrative exemptions or similar exemptions under Similar Law and (ii) direct the Trustee to
invest the assets held in the Trust pursuant to, and take all other actions contemplated by, the terms and conditions of the Basic Agreement, this Trust Supplement, the Intercreditor Agreement, the Deposit Agreement, the Escrow Agreement, the NPA,
and each Participation Agreement. 
 (i) The Class B Certificates will be subject to the following Intercreditor Agreement (and to the
extent the terms thereof (including the definitions of defined terms) are inconsistent with the terms of this Agreement, such Intercreditor Agreement shall control): that certain Intercreditor Agreement, dated as of the date hereof, among Wilmington
Trust, National Association, as Trustee and as Class A Trustee, Natixis, acting via its New York Branch, as each Liquidity Provider, and Wilmington Trust, National Association, as Subordination Agent thereunder (as may be amended, supplemented
or otherwise modified from time to time in accordance with its terms, the “Intercreditor Agreement”). Under Article VI hereof, the Holders of the Class B Certificates, Additional Certificates (if issued) or Refinancing Certificates (if
issued) shall have the rights upon the occurrence of a Certificate Buy Out Event set forth therein. The Trustee and, by acceptance of any Class B Certificate, each Certificateholder thereof, agrees to be bound by all of the provisions of the
Intercreditor Agreement, including the subordination provisions of Section 9.09 thereof. 
 (j) The Class B Certificates have the
benefit of the Deposit Agreement and the Escrow Agreement. 

  

					
		  	9	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 (k) The Class B Certificates will have the benefit of the following liquidity facility: that
certain Revolving Credit Agreement (2015-1B), dated as of the date hereof, between Wilmington Trust, National Association, as Subordination Agent under the Intercreditor Agreement, as agent and trustee for the Class B Trust, and the Class B
Liquidity Provider. 
 (l) The Responsible Party is the Company. 

(m) The Company, any other obligor upon the Class B Certificates, and any Affiliate of any thereof may acquire, tender for, purchase, own,
hold, become the pledgee of and otherwise deal with any Class B Certificate. 
 (n) The “particular sections of the Note Purchase
Agreement”, for purposes of clause (3) of Section 7.07 of the Basic Agreement, are Section 4.02 of each Participation Agreement. 

ARTICLE IV 
 ISSUANCE
AND TRANSFER OF THE CLASS B CERTIFICATES 
 Section 4.01 Issuance of Class B Certificates. (a) The Class B Certificates
will be issued in minimum denominations of $2,000 (or such other denomination that is the lowest integral multiple of $1,000 that is, at the time of issuance, equal to at least 1,000 euros) and integral multiples of $1,000 in excess thereof, except
that one Certificate may be issued in a different denomination. Each Class B Certificate shall be dated the date of its authentication. 

(b) The Class B Certificates shall be issued initially in the form of one or more global Certificates in definitive, fully registered form
without interest coupons, substantially in the form of Exhibit A hereto (each, a “Global Certificate”), duly executed and authenticated by the Trustee as hereinafter provided. Each Global Certificate will be registered in the name of
a nominee for DTC for credit to the account of members of, or participants in, DTC (“DTC Participants”) or to the account of indirect participants that clear through or maintain a custodial relationship with a DTC Participant, either
directly or indirectly (“Indirect Participants”), and will be deposited with the Trustee, as custodian for DTC. The aggregate principal amount of a Global Certificate may from time to time be decreased by adjustments made on the records of
DTC or its nominee, or of the Trustee, as custodian for DTC or its nominee, as hereinafter provided, which adjustments shall be conclusive as to the aggregate principal amount of any such Global Certificate. 

(c) [Reserved] 
 (d) [Reserved]

 (e) Certificated Certificates in registered form shall be issued in substantially the form set forth as Exhibit A hereto (the
“Definitive Certificates”) and shall be in fully registered form and shall be typed, printed, lithographed or engraved or produced by any combination of these methods or may be produced in any other manner, all as determined by the
officers executing such Definitive Certificates, as evidenced by their execution of such Definitive Certificates. 
 Section 4.02
Legends. (a) Each Global Certificate shall bear the following legend on the face thereof: 
 UNLESS THIS CERTIFICATE IS PRESENTED
BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE TRUSTEE OR ITS AGENT FOR 

  

					
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REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IN EXCHANGE FOR THIS CERTIFICATE IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO
ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN. 
 (b) Each Class B Certificate
shall bear the following legend on the face thereof: 
 BY ITS ACQUISITION HEREOF, THE HOLDER REPRESENTS THAT EITHER (A) NO ASSETS OF A
PLAN OR ANY TRUST ESTABLISHED WITH RESPECT TO A PLAN HAVE BEEN USED TO PURCHASE OR HOLD THIS CERTIFICATE OR AN INTEREST HEREIN OR (B) THE PURCHASE AND HOLDING OF THIS CERTIFICATE OR INTEREST HEREIN BY SUCH A PERSON ARE EXEMPT FROM THE
PROHIBITED TRANSACTION RESTRICTIONS OF ERISA AND THE CODE OR PROVISIONS OF SIMILAR LAW PURSUANT TO ONE OR MORE PROHIBITED TRANSACTION STATUTORY OR ADMINISTRATIVE EXEMPTIONS OR SIMILAR EXEMPTIONS UNDER SIMILAR LAW. CERTAIN TERMS USED IN THIS
PARAGRAPH SHALL HAVE THE MEANINGS SPECIFIED IN THE AGREEMENT. 
 Section 4.03 Book-Entry Provisions for Global Certificates.
(a) DTC Participants shall have no rights under this Agreement with respect to any Global Certificate held on their behalf by DTC, or the Trustee as its custodian, and DTC may be treated by the Trustee and any agent of the Trustee as the
absolute owner of such Global Certificate for all purposes whatsoever. Notwithstanding the foregoing, nothing herein shall prevent the Trustee or any agent of the Trustee from giving effect to any written certification, proxy or other authorization
furnished by DTC or shall impair, as between DTC and its DTC Participants, the operation of customary practices governing the exercise of the rights of a holder of any Class B Certificate. Upon the issuance of any Global Certificate, the Registrar
or its duly appointed agent shall record Cede & Co. or another nominee of DTC as the registered holder of such Global Certificate. 

(b) Transfers of any Global Certificate shall be limited to transfers of such Global Certificate in whole, but not in part, to nominees of
DTC, its successor or such successor’s nominees. Beneficial interests in Global Certificates may be transferred in accordance with the rules and procedures of DTC and the provisions of Section 4.02 of this Trust Supplement. Beneficial
interests in Global Certificates shall be delivered to all beneficial owners thereof in the form of Definitive Certificates, if (i) DTC notifies the Trustee in writing that it is no longer willing or able to discharge properly its
responsibilities as depositary for the Global Certificates, and a successor depositary is not appointed by the Trustee within 90 days of such notice, (ii) the Company, at its option, advises the Trustee in writing that it elects to
terminate the book-entry system through DTC or (iii) after the occurrence and during the continuance of an Event of Default, Class B Certificateholders with Fractional Undivided Interests aggregating not less than a majority in interest in the
Class B Trust advise the Trustee, the Company and DTC through DTC Participants in writing that the continuation of a book-entry system through DTC (or a successor thereto) is no longer in the Class B Certificateholders’ best interests. Neither
the Company nor the Trustee shall be liable if the Company or the Trustee is unable to locate a qualified successor clearing system. 
 (c)
[Reserved] 

  

					
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 (d) In connection with the transfer of the entire amount of a Global Certificate to the
beneficial owners thereof pursuant to paragraph (b) of this Section 4.03, such Global Certificate shall be deemed to be surrendered to the Trustee for cancellation, and the Trustee shall execute, authenticate and deliver to each beneficial
owner, in exchange for the beneficial interest thereof in such Global Certificate, an equal aggregate principal amount of Definitive Certificates of authorized denominations, in each case as such beneficial owner and related aggregate principal
amount shall have been identified and otherwise set forth (together with such other information as may be required for the registration of such Definitive Certificates) in registration instructions that shall have been delivered by or on behalf of
DTC to the Trustee. None of the Company, the Registrar, the Paying Agent nor the Trustee shall be liable for any delay in delivery of such registration instructions and each such Person may conclusively rely on, and shall be protected in relying on,
such registration instructions. Upon the issuance of any Definitive Certificate, the Trustee shall recognize the Person in whose name such Definitive Certificate is registered in the Register as a Certificateholder hereunder. 

(e) The registered Holder of a Global Certificate may grant proxies and otherwise authorize any Person, including DTC Participants and Persons
that may hold interests through DTC Participants, to take any action which a Holder is entitled to take under this Agreement or the Class B Certificates. 

(f) Neither the Company, nor the Trustee, nor the Registrar, nor the Paying Agent shall have any responsibility or liability for: (i) any
aspect of the records relating to or payments made on account of beneficial ownership interests in the Global Certificates, (ii) maintaining, supervising or reviewing any records relating to such beneficial ownership interests or (iii) the
performance by DTC, any DTC Participant or any Indirect Participant of their respective obligations under the rules, regulations and procedures creating and affecting DTC and its operation or any other statutory, regulatory, contractual or customary
procedures governing their obligations. 
 ARTICLE V 

DISTRIBUTION; STATEMENTS TO CERTIFICATEHOLDERS 

Section 5.01 Statements to Certificateholders. (a) On each Regular Distribution Date and Special Distribution Date, the
Trustee will include with each distribution to the Class B Certificateholders a statement, giving effect to the distribution to be made on such Regular Distribution Date or Special Distribution Date, setting forth the following information (per
$1,000 aggregate face amount of Class B Certificates as to clauses (ii), (iii), (iv) and (v) below): 
 (i) the
aggregate amount of funds distributed on such Distribution Date under this Agreement and the Escrow Agreement, indicating the amount, if any, allocable to each source (including any portion thereof paid by the Class B Liquidity Provider); 

(ii) the amount of such distribution under this Agreement allocable to principal and the amount allocable to Premium (if any);

 (iii) the amount of such distribution under this Agreement allocable to interest (including any portion thereof paid by
the Class B Liquidity Provider); 
 (iv) the amount of such distribution under the Escrow Agreement allocable to interest, if
any; 
 (v) the amount of such distribution under the Escrow Agreement allocable to unused Deposits, if any; and 

(vi) the Pool Balance and the Pool Factor. 

  

					
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 With respect to the Class B Certificates registered in the name of DTC or its nominee, on the
Record Date prior to each Regular Distribution Date and Special Distribution Date, the Trustee will request that DTC post on its Internet bulletin board a securities position listing setting forth the names of all the DTC Participants reflected on
DTC’s books as holding interests in the Class B Certificates on such Record Date. On each Regular Distribution Date and Special Distribution Date, the Trustee will mail to each such DTC Participant whose name has been provided by DTC the
statement described above and will make available additional copies as requested by such DTC Participants for forwarding to holders of interests in the Class B Certificates. 

(b) Within a reasonable period of time after the end of each calendar year but not later than the latest date permitted by law, the Trustee
shall furnish to each Person who at any time during such calendar year was a Class B Certificateholder of record a statement containing the sum of the amounts determined pursuant to clauses (a)(i), (a)(ii), (a)(iii), (a)(iv) and (a)(v) above
for such calendar year or, in the event such Person was a Class B Certificateholder of record during a portion of such calendar year, for the applicable portion of such year, and such other items as are readily available to the Trustee and which a
Class B Certificateholder may reasonably request as necessary for the purpose of such Certificateholder’s preparation of its United States federal income tax returns or foreign income tax returns. With respect to Class B Certificates registered
in the name of DTC or its nominee, such statement and such other items shall be prepared on the basis of information supplied to the Trustee by the DTC Participants and shall be delivered by the Trustee to such DTC Participants to be available for
forwarding by such DTC Participants to the holders of interests in the Class B Certificates. 
 (c) Promptly following: 

(i) the Delivery Period Termination Date, or, if later, the date of any Final Withdrawal (the later of such dates, the
“Escrow Period Termination Date”), if there has been, on or prior to the Escrow Period Termination Date, (A) any change in the information set forth in clauses (y) and (z) below from that set forth on page S-106 of the
Prospectus Supplement, or (B) any early redemption or purchase of, or any default in the payment of principal or interest in respect of, any of the Series B Equipment Notes held in the Class B Trust, any Event of Loss Withdrawal or any Final
Withdrawal, and 
 (ii) the date of any early redemption or purchase of, or any default in the payment of principal or
interest in respect of, any of the Series B Equipment Notes held in the Class B Trust, in either case described in this clause (ii), occurring after the Escrow Period Termination Date, 

the Trustee shall furnish to Class B Certificateholders of record on such date a statement setting forth (x) the expected Pool Balances
for each subsequent Regular Distribution Date following the Delivery Period Termination Date, (y) the related Pool Factors for such Regular Distribution Dates and (z) the expected principal distribution schedule of the Series B Equipment
Notes, in the aggregate, held as Trust Property at the date of such notice. With respect to the Class B Certificates registered in the name of DTC, on the Delivery Period Termination Date, the Trustee will request from DTC a securities position
listing setting forth the names of all DTC Participants reflected on DTC’s books as holding interests in the Class B Certificates on such date. The Trustee will mail to each such DTC Participant the statement described above and will make
available additional copies as requested by such DTC Participant for forwarding to holders of interests in the Class B Certificates. 
 (d)
If the aggregate principal payments scheduled for a Regular Distribution Date prior to the Delivery Period Termination Date differ from the amount thereof set forth for the Class B Certificates on page S-106 of the Prospectus Supplement, by no later
than the 15th day prior to such Regular Distribution Date, the Trustee shall mail written notice of the actual amount of such scheduled payments to the Class B Certificateholders of record as of a date within 15 Business Days prior to the date of
mailing. 
 (e) The provisions of this Section 5.01 supersede and replace the provisions of Section 4.03 of the Basic Agreement in
their entirety with respect to the Class B Trust. 

  

					
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 ARTICLE VI 

DEFAULT 

Section 6.01 Purchase Rights of Certificateholders. (a) By acceptance of its Class B Certificate, each Class B
Certificateholder agrees that at any time after the occurrence and during the continuation of a Certificate Buy-Out Event: 

(i) so long as no Additional Certificateholder has elected to exercise its rights to purchase Certificates pursuant to, and
given notice of such election in accordance with, this Section 6.01(a) (upon such election and notification thereof, the right specified in this Section 6.01(a)(i) shall be suspended and (x) upon consummation of the purchase pursuant
to such election, be terminated with respect to such Certificate Buy-Out Event, or (y) upon failure to consummate such purchase on the proposed purchase date, such right shall be revived), each Class B Certificateholder (other than the Company
or any of its Affiliates) shall have the right to purchase, at the purchase price set forth in the Class A Trust Agreement, all, but not less than all, of the Class A Certificates upon ten days’ prior written irrevocable notice to the
Trustee, the Class A Trustee and each other Class B Certificateholder, on the third Business Day following the expiration of such ten-day notice period, provided that (A) if prior to the end of such ten-day period any other Class B
Certificateholder(s) (other than the Company or any of its Affiliates) notifies such purchasing Class B Certificateholder that such other Class B Certificateholder(s) want(s) to participate in such purchase, then such other Class B
Certificateholder(s) (other than the Company or any of its Affiliates) may join with the purchasing Class B Certificateholder to purchase all, but not less than all, of the Class A Certificates pro rata based on the Fractional Undivided
Interest in the Class B Trust held by each such Class B Certificateholder and (B) upon consummation of such purchase no Class B Certificateholder shall have a right to purchase the Class A Certificates pursuant to this
Section 6.01(a)(i) during the continuance of such Certificate Buy-Out Event, 
 (ii) if any Additional Certificates are
issued by an Additional Trust, so long as no Junior Additional Certificateholder (if any) has elected to exercise its rights to purchase Certificates pursuant to, and given notice of such election in accordance with, this Section 6.01(a) (upon
such election and notification thereof, the right specified in this Section 6.01(a)(ii) shall be suspended and (x) upon consummation of the purchase pursuant to such election, be terminated with respect to such Certificate Buy-Out Event,
or (y) upon failure to consummate such purchase on the proposed purchase date, such right shall be revived), each Additional Certificateholder (other than the Company or any of its Affiliates) shall have the right (which shall not expire upon
any purchase of the Class A Certificates pursuant to clause (i) above) to purchase all, but not less than all, of the Class A Certificates, the Class B Certificates and any Additional Certificates ranked senior, in priority of payment
of “Expected Distributions” therefor under the Intercreditor Agreement, to the Additional Certificates held by the purchasing Additional Certificateholder upon ten days’ prior written irrevocable notice to the Trustee, the
Class A Trustee, the trustee of any Additional Trust with respect to any Additional Certificates that rank senior, in priority of payment of “Expected Distributions” therefor under the Intercreditor Agreement, to the Additional
Certificates held by the purchasing Additional Certificateholder and each other Additional Certificateholder of the same class, on the third Business Day following the expiration 

  

					
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of such ten-day notice period, provided that (A) if prior to the end of such ten-day period any other Additional Certificateholder(s) of such class (other than the Company or any of
its Affiliates) notifies such purchasing Additional Certificateholder that such other Additional Certificateholder(s) want(s) to participate in such purchase, then such other Additional Certificateholder(s) (other than the Company or any of its
Affiliates) may join with the purchasing Additional Certificateholder to purchase all, but not less than all, of the Class A Certificates, the Class B Certificates and such senior Additional Certificates pro rata based on the Fractional
Undivided Interest in the applicable Additional Trust held by each such Additional Certificateholder and (B) upon consummation of such purchase no Additional Certificateholder of such class shall have a right to purchase the Class A
Certificates, the Class B Certificates and such senior Additional Certificates pursuant to this Section 6.01(a)(ii) during the continuance of such Certificate Buy-Out Event, and 

(iii) if any Refinancing Certificates are issued, each Refinancing Certificateholder shall have the same right (subject to the
same terms and conditions) to purchase Certificates pursuant to this Section 6.01(a) (and to receive notice in connection therewith) as the Holders of the Class that such Refinancing Certificates refinanced. 

The purchase price with respect to the Class B Certificates shall be equal to the Pool Balance of the Class B Certificates, together with
accrued and unpaid interest in respect thereof to the date of such purchase, and any other amounts then due and payable to the Class B Certificateholders under this Agreement, the Intercreditor Agreement, the Escrow Agreement, any Series B Equipment
Note held as the property of the Class B Trust or the related Indenture and Participation Agreement or on or in respect of the Class B Certificates but without any Premium, provided, however, that if such purchase occurs after
(x) a record date specified in Section 2.03 of the Escrow Agreement relating to the distribution of unused Deposits and/or accrued and unpaid interest on Deposits and prior to or on the related distribution date under the Escrow Agreement,
such purchase price shall be reduced by the aggregate amount of unused Deposits and/or interest to be distributed under the Escrow Agreement (which deducted amounts shall remain distributable to, and may be retained by, the Class B
Certificateholders as of such record date) or (y) the Record Date relating to any Distribution Date, such purchase price shall be reduced by the amount to be distributed hereunder on such related Distribution Date (which deducted amounts shall
remain distributable to, and may be retained by, the Class B Certificateholders as of such Record Date); provided further that no such purchase of Class B Certificates pursuant to this Section 6.01(a) shall be effective unless the
purchaser(s) shall certify to the Trustee that contemporaneously with such purchase, such purchaser(s) is purchasing, pursuant to the terms of this Agreement, the Class A Trust Agreement, the applicable Additional Trust Agreement (if any) or
the applicable Refinancing Trust Agreement (as the case may be), and the Intercreditor Agreement, all of the Class A Certificates, the Class B Certificates and, if applicable, the Additional Certificates that rank senior, in priority of payment
of “Expected Distributions” therefor under the Intercreditor Agreement, to the Additional Certificates held by the purchasing Additional Certificateholder(s) and, if applicable, the Refinancing Certificates that are senior to the
securities held by such purchaser(s). Each payment of the purchase price of the Class B Certificates referred to in the first sentence of this paragraph shall be made to an account or accounts designated by the Trustee and each such purchase shall
be subject to the terms of this Section 6.01(a). Each Class B Certificateholder agrees by its acceptance of its Class B Certificate that it will, upon payment from such Additional Certificateholder(s) or Refinancing Certificateholder(s), as the
case may be, of the purchase price set forth in the first sentence of this paragraph, forthwith sell, assign, transfer and convey to the purchaser(s) thereof (without recourse, representation or warranty of any kind except as to its own acts) all of
the right, title, interest and obligation of such Class B Certificateholder in this Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Class B Liquidity Facility, the NPA, the Note Documents and all Class B
Certificates and Escrow Receipts held by such Class B Certificateholder (excluding all right, title and interest under any of 

  

					
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the foregoing to the extent such right, title or interest is with respect to an obligation not then due and payable as respects any action or inaction or state of affairs occurring prior to such
sale) and the purchaser(s) shall assume all of such Class B Certificateholder’s obligations under this Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Class B Liquidity Facility, the NPA, the Note
Documents and all such Class B Certificates and Escrow Receipts. The Class B Certificates will be deemed to be purchased on the date payment of the purchase price is made notwithstanding the failure of any Class B Certificateholder to deliver any
Class B Certificate and, upon such a purchase, (i) the Class B Certificateholders shall have no further rights with respect to the Class B Certificates and (ii) if the purchaser(s) shall so request, each such Class B Certificateholder will
comply with all the provisions of Section 3.04 of the Basic Agreement and the applicable provisions of this Trust Supplement to enable new Class B Certificates to be issued to the purchaser(s) in such denominations otherwise authorized under
this Agreement as it shall request. All charges and expenses in connection with the issuance of any such new Class B Certificates shall be borne by the purchaser(s) thereof. 

(b) This Section 6.01 supplements and, to the extent inconsistent with any provision of Section 6.01(b) of the Basic Agreement,
replaces the provisions of Section 6.01(b) of the Basic Agreement. Notwithstanding anything to the contrary set forth herein or in any Operative Agreement, the provisions of this Section 6.01 may not be amended in any manner without the
consent of each Class A Certificateholder, each Class B Certificateholder and each Additional Certificateholder (if any) or, as the case may be, Refinancing Certificateholder (if any) (in each case, other than the Company or any of its
Affiliates in its respective capacity as a Certificateholder) that would be adversely affected thereby; provided that the purchase price under this Section 6.01 (as in effect on the date hereof) for any Certificate held by the Company or
any of its Affiliates shall not be modified without the prior written consent of the Company. For the avoidance of doubt, if a Certificate Buy-Out Event ceases to exist and another Certificate Buy-Out Event occurs and is continuing, the purchase
rights set forth in Section 6.01(a) shall be revived notwithstanding any exercise of such rights during the continuance of any preceding Certificate Buy-Out Event. 

ARTICLE VII 
 THE
TRUSTEE 
 Section 7.01 Delivery of Documents; Delivery Dates. (a) The Trustee is hereby directed (i) to execute
and deliver the Intercreditor Agreement, the Escrow Agreement and the NPA on or prior to the date of the initial issuance of the Class B Certificates (the “Issuance Date”), each in the form delivered to the Trustee by the Company, and
(ii) subject to the respective terms thereof, to perform its obligations thereunder. Upon request of the Company and the satisfaction or waiver of the closing conditions specified in the Underwriting Agreement, the Trustee shall execute,
deliver, authenticate, issue and sell Class B Certificates in authorized denominations equaling in the aggregate the amount set forth, with respect to the Class B Trust, in Schedule I to the Underwriting Agreement evidencing the entire ownership
interest in the Class B Trust, which amount equals the maximum aggregate principal amount of Series B Equipment Notes which may be purchased from time to time by the Trustee pursuant to the NPA. Except as provided in Sections 3.03, 3.04, 3.05
and 3.06 of the Basic Agreement or Section 4.03 of this Trust Supplement, the Trustee shall not execute, authenticate or deliver Class B Certificates in excess of the aggregate amount specified in this paragraph. The provisions of this
Section 7.01(a) supersede and replace the first three sentences of Section 2.02(a) of the Basic Agreement and the first sentence of Section 3.02(a) of the Basic Agreement, with respect to the Class B Trust. 

(b) On or after the Issuance Date, the Company may deliver from time to time, and in accordance with Section 1(b) of the NPA, to the
Trustee a Funding Notice relating to one or more Series B Equipment Notes. After receipt of such a Funding Notice and in any case no later than one Business Day prior to a Funding Date as to which such Funding Notice relates (the “Applicable
Funding 

  

					
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Date”), the Trustee shall (as and when specified in the Funding Notice) deliver to the Escrow Agent the Withdrawal Certificates and related Applicable Notices of Purchase Withdrawal, as
contemplated by Section 1.02(c) of the Escrow Agreement and by such Funding Notice. The Trustee shall (as and when specified in such Funding Notice), subject to the conditions set forth in Section 2 of the NPA, enter into and perform its
obligations under the Participation Agreement specified in such Funding Notice (the “Applicable Participation Agreement”) and cause such certificates, documents and legal opinions relating to the Trustee to be duly delivered as required by
the Applicable Participation Agreement. If at any time prior to the Applicable Funding Date, the Trustee receives from the Company a notice pursuant to the first sentence of Section 1(f) of the NPA, then the Trustee shall give notice to the
Depositary (with a copy to the Escrow Agent) of the cancellation of such Notice of Purchase Withdrawal relating to such Deposit or Deposits on such Applicable Funding Date as contemplated by Section 2.3 of the Deposit Agreement. Upon
satisfaction of the conditions specified in the NPA and the Applicable Participation Agreement, the Trustee shall purchase the applicable Series B Equipment Notes with the proceeds of the withdrawals of one or more Deposits made on the Applicable
Funding Date in accordance with the terms of the Deposit Agreement and the Escrow Agreement. The purchase price of such Series B Equipment Notes shall equal the principal amount of such Series B Equipment Notes. Amounts withdrawn from such Deposit
or Deposits in excess of the purchase price of the Series B Equipment Notes or to the extent not applied on the Applicable Funding Date to the purchase price of the Series B Equipment Notes shall be re-deposited by the Trustee with the Depositary on
the Applicable Funding Date in accordance with the terms of the Deposit Agreement. The provisions of this Section 7.01(b) supersede and replace the last sentence of Section 2.02(a) of the Basic Agreement and the provisions of
Section 2.02(b) of the Basic Agreement with respect to the Class B Trust, and no provisions of the Basic Agreement relating to Postponed Notes and Section 2.02(b) of the Basic Agreement shall apply to the Class B Trust. 

(c) With respect to the Class B Trust, Section 4.01(b) of the Basic Agreement is superseded and replaced in its entirety with the
following: “The Trustee shall establish and maintain on behalf of the Class B Certificateholders a Special Payments Account as one or more accounts, which shall be non-interest bearing except as provided in Section 4.04 of the Basic
Agreement. The Trustee shall hold the Special Payments Account in trust for the benefit of the Class B Certificateholders and shall make or permit withdrawals therefrom only as provided in the Agreement or the Intercreditor Agreement. On each day
when one or more Special Payments are made to the Trustee under the Intercreditor Agreement, the Trustee, upon receipt thereof, shall immediately deposit the aggregate amount of such Special Payments in the Special Payments Account.” 

(d) With respect to the Class B Trust, the second through fifth sentences of Section 4.02(c) of the Basic Agreement shall be superseded
and replaced in their entirety with the following sentence: “Subject to the provisions of the Intercreditor Agreement: (i) in the event of redemption or purchase of Series B Equipment Notes held in the Class B Trust, such notice shall be
mailed not less than 15 days prior to the Special Distribution Date for the Special Payment resulting from such redemption or purchase, which Special Distribution Date shall be the date of such redemption or purchase; and (ii) in the case of
any other Special Payments, such notice of Special Payment shall be mailed as soon as practicable after the Trustee has confirmed that it has received funds for such Special Payment and shall state the Special Distribution Date for such Special
Payment, which shall occur 15 days after the date of such notice of Special Payment or (if such 15th day is not practicable) as soon as practicable thereafter.” 

(e) With respect to the Class B Trust, clause (ii) of the sixth sentence of Section 4.02(c) of the Basic Agreement shall be amended
by deleting in its entirety the parenthetical phrase “(taking into account any payment to be made by the Company pursuant to Section 2.02(b)).” 

Section 7.02 Withdrawal of Deposits. If any Deposits remain outstanding on the Business Day next succeeding the Cut-off Date, the
Trustee shall promptly give the Escrow Agent notice, as contemplated by clause (ii) of Section 1.02(f) of the Escrow Agreement, that the Trustee’s obligation to purchase Series B Equipment Notes under the NPA has terminated and the
Cut-off Date has occurred. 

  

					
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 Section 7.03 The Trustee. (a) Subject to Section 7.04 of this Trust
Supplement and Section 7.15 of the Basic Agreement, the Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Trust Supplement, the Intercreditor Agreement, the Deposit Agreement, the
NPA or the Escrow Agreement or the due execution hereof or thereof by the Company or the other parties thereto (other than the Trustee), or for or in respect of the recitals and statements contained herein or therein, all of which recitals and
statements are made solely by the Company or the other parties thereto (other than the Trustee), except that the Trustee hereby represents and warrants that each of this Trust Supplement, the Basic Agreement, each Class B Certificate, the
Intercreditor Agreement, the NPA and the Escrow Agreement has been executed and delivered by one of its officers who is duly authorized to execute and deliver such document on its behalf. 

(b) In addition to the requirements in Section 7.08 of the Basic Agreement, the Trustee shall at all times be a bank or trust company,
organized and doing business under the laws of the United States or any state thereof, a substantial part of the business of which consists of (i) receiving deposits and making loans or (ii) exercising fiduciary powers similar to those
permitted to national banks by the Comptroller of the Currency, and which is subject to supervision and examination by state or federal authority having supervision over banking institutions. 

Section 7.04 Representations and Warranties of the Trustee. The Trustee hereby represents and warrants that: 

(a) the Trustee has full power, authority and legal right to execute, deliver and perform this Trust Supplement, the Intercreditor Agreement,
the Escrow Agreement, the NPA, the Class B Certificates and the Note Documents to which it is or is to become a party and has taken all necessary action to authorize the execution, delivery and performance by it of this Trust Supplement, the
Intercreditor Agreement, the Escrow Agreement, the NPA, the Class B Certificates and the Note Documents to which it is or is to become a party; 

(b) the execution, delivery and performance by the Trustee of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the
NPA, the Class B Certificates and the Note Documents to which it is or is to become a party (i) will not violate any provision of any United States federal law governing its banking powers or the law of the state of the United States where it
is located governing the banking and trust powers of the Trustee or any order, writ, judgment, or decree of any court, arbitrator or governmental authority applicable to the Trustee or any of its assets, (ii) will not violate any provision of
the articles of association or by-laws of the Trustee, and (iii) will not violate any provision of, or constitute, with or without notice or lapse of time, a default under, or result in the creation or imposition of any lien on any properties
included in the Trust Property pursuant to the provisions of, any mortgage, indenture, contract, agreement or other undertaking to which it is a party, which violation, default or lien could reasonably be expected to have an adverse effect on the
Trustee’s performance or ability to perform its duties hereunder or thereunder or on the transactions contemplated herein or therein; 

(c) the execution, delivery and performance by the Trustee of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the
NPA, the Class B Certificates and the Note Documents to which it is or is to become a party will not require the authorization, consent, or approval of, the giving of notice to, the filing or registration with, or the taking of any other action in
respect of, any governmental authority or agency of the United States or the state of the United States where it is located regulating the banking and corporate trust activities of the Trustee; and 

(d) this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA, the Class B Certificates and the Note Documents to
which it is or is to become a party have been, or 

  

					
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will be, as applicable, duly executed and delivered by the Trustee and constitute, or will constitute, as applicable, the legal, valid and binding agreements of the Trustee, enforceable against
it in accordance with their respective terms; provided, however, that enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally
and (ii) general principles of equity. 
 Section 7.05 Trustee Liens. The Trustee in its individual capacity agrees, in
addition to the agreements contained in Section 7.17 of the Basic Agreement, that it will at its own cost and expense promptly take any action as may be necessary to duly discharge and satisfy in full any Trustee’s Liens on or with respect
to the Trust Property which are attributable to the Trustee in its individual capacity and which are unrelated to the transactions contemplated by the Intercreditor Agreement or the NPA. 

ARTICLE VIII 

ADDITIONAL AMENDMENT; SUPPLEMENTAL AGREEMENTS 

Section 8.01 Amendment of Sections 5.02, 6.07, 7.09, 8.04, 9.01, 12.01 and 12.02 of the Basic Agreement. For purposes of this
Agreement, the Basic Agreement shall be deemed amended as follows: 
 (a) Section 5.02 of the Basic Agreement shall be deemed amended
and restated in its entirety to read as set forth in Part A of Exhibit C. 
 (b) Section 6.07 of the Basic Agreement shall be deemed
amended and restated in its entirety to read as set forth in Part B of Exhibit C. 
 (c) Section 7.09 of the Basic Agreement shall be
deemed amended by amending and restating the second sentence of subsection (e) thereof in its entirety to read as set forth in Part C of Exhibit C. 

(d) Section 8.04 of the Basic Agreement shall be deemed amended by amending and restating subsection (a) thereof in its entirety to
read as set forth in Part D of Exhibit C. 
 (e) Section 9.01 of the Basic Agreement shall be deemed amended by amending and restating
clause (4) thereof in its entirety to read as set forth in Part E of Exhibit C. 
 (f) Section 12.01 of the Basic Agreement shall
be deemed amended and restated in its entirety to read as set forth in Part F of Exhibit C. 
 (g) Section 12.02 of the Basic Agreement
shall be deemed amended and restated in its entirety to read as set forth in Part G of Exhibit C. 
 Section 8.02 Supplemental
Agreements Without Consent of Class B Certificateholders. Without limitation of Section 9.01 of the Basic Agreement (for the avoidance of doubt, as amended by Section 8.01 above), under the terms of, and subject to the limitations
contained in, such Section 9.01 of the Basic Agreement, the Company may (but will not be required to), and the Trustee (subject to Section 9.03 of the Basic Agreement) shall, at the Company’s request, at any time and from time to
time, enter into (or, in the case of the Deposit Agreement, consent to) and, if applicable, request the Escrow Agent and Escrow Paying Agent to enter into (i) one or more agreements supplemental to the Escrow Agreement, the NPA or the Deposit
Agreement, for any of the purposes set forth in clauses (1) through (9) of such Section 9.01, and (without limitation of the foregoing or Section 9.01 of the Basic Agreement) (a) clauses (2) and (3) of such
Section 9.01 shall also be deemed to include the Company’s obligations under (in the case of clause (2)), and the Company’s rights and powers 

  

					
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conferred by (in the case of clause (3)), the NPA and any Participation Agreement, (b) references in clauses (4) and (6) of such Section 9.01 to “any
Intercreditor Agreement or any Liquidity Facility” shall also be deemed to refer to “the Intercreditor Agreement, the Class B Liquidity Facility, the Escrow Agreement, the NPA, any Participation Agreement or the Deposit Agreement”,
and (c) references to “any Intercreditor Agreement or any Liquidity Facility” in clause (7) of such Section 9.01 shall also be deemed to refer to “the Intercreditor Agreement, the NPA, any Indenture, the Class B
Liquidity Facility, the Escrow Agreement, the Deposit Agreement or any Participation Agreement”, (ii) one or more agreements supplemental to any Operative Agreement, the NPA, the Escrow Agreement or the Deposit Agreement to provide for the
formation of one or more Additional Trusts, the issuance of one or more Classes of Additional Certificates, the purchase by any Additional Trust of applicable Additional Equipment Notes and other matters incidental thereto or as otherwise
contemplated by Section 2.01(b) of the Basic Agreement, all as provided in Section 4(a)(v) of the NPA and Section 8.01(d) of the Intercreditor Agreement, and (iii) one or more agreements supplemental to any Operative Agreement,
the NPA, the Escrow Agreement or the Deposit Agreement to provide for the formation of one or more Refinancing Trusts, the issuance of one or more Classes of Refinancing Certificates, the purchase by any Refinancing Trust of applicable Refinancing
Equipment Notes and other matters incidental thereto or as otherwise contemplated by Section 2.01(b) of the Basic Agreement, all as provided in Section 4(a)(v) of the NPA and Section 8.01(c) of the Intercreditor Agreement. In
addition, the following provisions of Section 9.01 of the Basic Agreement shall be amended, with respect to the Class B Trust, as follows: (A) Section 9.01(5) of the Basic Agreement shall be amended by inserting the phrase “(or
to facilitate any listing of any Certificates on any exchange or quotation system) or any requirement of DTC or like depositary,” after the phrase “any exchange or quotation system on which the Certificates of any series are listed”
but before the phrase “or of any regulatory body”; (B) Section 9.01(6) of the Basic Agreement shall be amended by inserting the phrase “to establish or” after the phrase “to such extent as shall be necessary”
but before the phrase “to continue”; and (C) Section 9.01(7) of the Basic Agreement shall be amended by replacing the phrase “and to add to or change” with the phrase “, or to evidence the substitution of a
Liquidity Provider with a Replacement Liquidity Provider or to provide for a Replacement Liquidity Facility, all as provided in any Intercreditor Agreement; or to evidence the substitution of a Depositary with a Replacement Depositary or to provide
for a Replacement Deposit Agreement, all as provided in the NPA; or to evidence and provide for the acceptance of appointment by a successor Escrow Agent or successor Escrow Paying Agent under the Escrow Agreement; or to provide multiple Liquidity
Facilities with respect to one or more Trusts; or to add to or change”. 
 Section 8.03 Supplemental Agreements with Consent of
Class B Certificateholders. Without limitation of Section 9.02 of the Basic Agreement, the provisions of Section 9.02 of the Basic Agreement shall apply to agreements or amendments for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of the Escrow Agreement, the Deposit Agreement, the Class B Liquidity Facility or the NPA or modifying in any manner the rights and obligations of the Class B Certificateholders under the
Escrow Agreement, the Deposit Agreement, the Class B Liquidity Facility or the NPA; provided that the provisions of Section 9.02(1) of the Basic Agreement shall be deemed to include reductions in any manner of, or delay in the timing of, any
receipt by the Class B Certificateholders of payments upon the Deposits. 
 Section 8.04 Consent of Trustees for Amendment of
Section 6.01. Notwithstanding any provision in Section 8.02 or Section 8.03 of this Trust Supplement to the contrary, no amendment or modification of Section 6.01 of this Trust Supplement shall be effective unless the trustee
for each Class of Certificates affected by such amendment or modification shall have consented thereto. 

  

					
		  	20	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 ARTICLE IX 

MISCELLANEOUS PROVISIONS 

Section 9.01 Final Termination Date. The respective obligations and responsibilities of the Company and the Trustee created hereby
and the Class B Trust created hereby shall terminate upon the distribution to all Class B Certificateholders and the Trustee of all amounts required to be distributed to them pursuant to this Agreement and the disposition of all property held as
part of the Trust Property; provided, however, that in no event shall the Trust created hereby continue beyond the expiration of 21 years from the death of the last survivor of the descendants of Joseph P. Kennedy, Sr., the father of John F.
Kennedy, former President of the United States, living on the date of this Trust Supplement. 
 Notice of any termination of the Class B
Trust, specifying the applicable Regular Distribution Date (or applicable Special Distribution Date, as the case may be) upon which the Class B Certificateholders may surrender their Class B Certificates to the Trustee for payment of the final
distribution and cancellation, shall be mailed promptly by the Trustee to the Class B Certificateholders not earlier than 60 days and not later than 15 days preceding such final distribution. 

Section 9.02 Basic Agreement Ratified. Except and so far as herein expressly provided, all of the provisions, terms and conditions
of the Basic Agreement are in all respects ratified and confirmed; and the Basic Agreement and this Trust Supplement shall be taken, read and construed as one and the same instrument. To the extent that any provisions of the Basic Agreement are
superseded by any provisions of this Trust Supplement, any reference to such provisions of the Basic Agreement herein or in the Basic Agreement shall be deemed to be to such provisions of this Trust Supplement. 

Section 9.03 Governing Law. THIS AGREEMENT HAS BEEN DELIVERED IN THE STATE OF NEW YORK AND THIS AGREEMENT AND THE CLASS B
CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK, INCLUDING ALL MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE. 

Section 9.04 Counterparts. This Trust Supplement may be executed in any number of counterparts (and each of the parties shall
not be required to execute the same counterpart). Each counterpart of this Trust Supplement including a signature page or pages executed by each of the parties hereto shall be an original counterpart of this Trust Supplement, but all of such
counterparts together shall constitute one instrument. 
 Section 9.05 Intention of Parties. The parties hereto intend that the
Class B Trust be classified for United States federal income tax purposes as a grantor trust under Subpart E, Part I, Subchapter J, Chapter 1 of Subtitle A of the Code, and not as a trust or association taxable as a corporation or as a
partnership. Each Certificateholder of, and each Person acquiring a beneficial interest in, a Class B Certificate, by its acceptance of its Class B Certificate or a beneficial interest therein, agrees to treat the Class B Trust as a grantor trust
for all United States federal, state and local income tax purposes. The Trustee shall not be authorized or empowered to do anything that would cause the Class B Trust to fail to qualify as a grantor trust for such tax purposes (including as subject
to this restriction, acquiring any Aircraft by bidding the Equipment Notes relating thereto or otherwise, or taking any action with respect to any such Aircraft once acquired). 

Section 9.06 Submission to Jurisdiction. Each of the parties hereto, to the extent it may do so under applicable law, for purposes
hereof and of all other Operative Agreements hereby (i) irrevocably submits itself to the non-exclusive jurisdiction of the courts of the State of New York sitting in the City of New York and to the non-exclusive jurisdiction of the United
States District Court for the Southern District of New York, for the purposes of any suit, action or other proceeding arising out of this 

  

					
		  	21	  	Trust Supplement No. 2015-1B
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Agreement, the subject matter hereof or any of the transactions contemplated hereby brought by any party or parties hereto or thereto, or their successors or permitted assigns and
(ii) waives, and agrees not to assert, by way of motion, as a defense, or otherwise, in any such suit, action or proceeding, that the suit, action or proceeding is brought in an inconvenient forum, that the venue of the suit, action or
proceeding is improper or that this Agreement or the subject matter hereof or any of the transactions contemplated hereby may not be enforced in or by such courts. 

Section 9.07 Successor and Assigns. All covenants, agreements, representations and warranties in this Agreement by the Trustee and
the Company shall bind and, to the extent permitted hereby, shall inure to the benefit of and be enforceable by their respective successors and assigns, whether so expressed or not. Any request, notice, direction, consent, waiver or other instrument
or action by any Class B Certificateholder shall bind the successors and assigns of such Class B Certificateholder. 
 Section 9.08
Normal Commercial Relations. Anything contained in this Agreement to the contrary notwithstanding, the Trustee and any Class B Certificateholder, or any bank or other affiliate of any such party, may conduct any banking or other financial
transactions, and have banking and other commercial relationships, with the Company fully to the same extent as if this Agreement were not in effect, including without limitation the making of loans or other extensions of credit to the Company for
any purpose whatsoever, whether related to any of the transactions contemplated hereby or otherwise. 
 Section 9.09 No Recourse
against Others. No past, present or future director, officer, employee, agent, member, manager, trustee or stockholder, as such, of the Company or any successor Person shall have any liability for any obligations of the Company or any successor
Person, either directly or through the Company or any successor Person, under the Class B Certificates or this Agreement or for any claim based on, in respect of or by reason of such obligations or their creation, whether by virtue of any rule of
law, statute or constitutional provision of by the enforcement of any assessment or by any legal or equitable proceeding or otherwise. By accepting a Class B Certificate, each Class B Certificateholder agrees to the provisions of this
Section 9.09 and waives and releases all such liability. Such waiver and release shall be part of the consideration for the issue of the Class B Certificates. 

[Remainder of Page Intentionally Blank; Signature Pages Follow] 

  

					
		  	22	  	Trust Supplement No. 2015-1B
		  		  	(Spirit 2015-1 EETC)

 IN WITNESS WHEREOF, the parties have caused this Trust Supplement to be duly executed by their
respective officers thereto duly authorized as of the date first written above. 
  

			
	SPIRIT AIRLINES, INC.
		
	By:	 	 /s/ Edward Christie

		 	Name: Edward Christie
		 	 Title: Senior Vice President and

          Chief Financial Officer

  
 Signature Page 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 
			
	WILMINGTON TRUST, NATIONAL ASSOCIATION,
	as Trustee
		
	By:	 	 /s/ Scott Wetzel

		 	Name: Scott Wetzel
		 	Title: Financial Services Officer

  
 Signature Page 

  
 Trust Supplement No.
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 (Spirit 2015-1 EETC) 

 EXHIBIT A to 

TRUST SUPPLEMENT NO. 2015-1B 

FORM OF CERTIFICATE 
 [UNLESS THIS
CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE TRUSTEE OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IN EXCHANGE
FOR THIS CERTIFICATE IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]* 

BY ITS ACQUISITION HEREOF, THE HOLDER REPRESENTS THAT EITHER (A) NO ASSETS OF A PLAN OR ANY TRUST ESTABLISHED WITH RESPECT TO A PLAN HAVE BEEN USED TO
PURCHASE OR HOLD THIS CERTIFICATE OR AN INTEREST HEREIN OR (B) THE PURCHASE AND HOLDING OF THIS CERTIFICATE OR INTEREST HEREIN BY SUCH A PERSON ARE EXEMPT FROM THE PROHIBITED TRANSACTION RESTRICTIONS OF ERISA AND THE CODE OR PROVISIONS OF
SIMILAR LAW PURSUANT TO ONE OR MORE PROHIBITED TRANSACTION STATUTORY OR ADMINISTRATIVE EXEMPTIONS OR SIMILAR EXEMPTIONS UNDER SIMILAR LAW. CERTAIN TERMS USED IN THIS PARAGRAPH SHALL HAVE THE MEANINGS SPECIFIED IN THE AGREEMENT. 

 

	*	This legend to appear on Book-Entry Certificates to be deposited with The Depositary Trust Company. 

  
 Trust Supplement No.
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 [GLOBAL CERTIFICATE]† 

SPIRIT AIRLINES PASS THROUGH TRUST 2015-1B 

SPIRIT AIRLINES PASS THROUGH CERTIFICATE, SERIES 2015-1B 

Final Expected Regular Distribution Date: April 1, 2024 

evidencing a fractional undivided interest in the Trust, the property of which includes or will include, among other things, certain Equipment
Notes each secured by an Aircraft owned by Spirit Airlines, Inc. 
  

					
	Certificate No.     	  	$         Fractional Undivided Interest representing 0.0008267264114286659% of the Trust per $1,000 face amount	  	 CUSIP No. 84858E AA4
  

ISIN No. US84858EAA47

 THIS CERTIFIES THAT             , for value
received, is the registered owner of a $         (        dollars) Fractional Undivided Interest (or such lesser amounts as shall be the aggregate outstanding face
amount hereof as set forth in the records of the Trustee) in the Spirit Airlines Pass Through Trust, Series 2015-1B (the “Trust”) created by WILMINGTON TRUST, NATIONAL ASSOCIATION, as trustee (together with any successor in interest
and any successor or other trustee appointed pursuant to the Trust Supplement referred to below, the “Trustee”) under a Pass Through Trust Agreement, dated as of August 11, 2015 (the “Basic Agreement”), between Wilmington
Trust, National Association and Spirit Airlines, Inc., a Delaware corporation (together with any successor in interest pursuant to Section 5.02 of the Basic Agreement, the “Company”), as supplemented by Trust Supplement
No. 2015-1B thereto dated as of August 11, 2015 (collectively, and as may be amended from time to time, the “Agreement”), between the Trustee and the Company, a summary of certain of the pertinent provisions of which is set forth
below. To the extent not otherwise defined herein, the capitalized terms used herein have the meanings assigned to them in the Agreement. This Certificate is one of the duly authorized Certificates designated as “Spirit Airlines Pass Through
Certificates, Series 2015-1B” (herein called the “Certificates”). This Certificate is issued under and is subject to the terms, provisions and conditions of the Agreement. By virtue of its acceptance hereof, the Certificateholder
of this Certificate assents to and agrees to be bound by all of the provisions of the Agreement and the Intercreditor Agreement, including the subordination provisions of Section 9.09 of the Intercreditor Agreement. The Trust Property is
expected to include certain Equipment Notes and includes all rights of the Trust and the Trustee, on behalf of the Trust, to receive any payments under the Intercreditor Agreement and the Class B Liquidity Facility. Each issue of the Equipment Notes
will be secured by, among other things, a security interest in the Aircraft owned by the Company. 
 The Certificates represent Fractional
Undivided Interests in the Trust and the Trust Property, and will have no rights, benefits or interest in respect of any other separate trust established pursuant to the terms of the Basic Agreement for any other series of certificates issued
pursuant thereto. 
 Subject to and in accordance with the terms of the Agreement and the Intercreditor Agreement, from funds then available
to the Trustee, there will be distributed on each April 1 and October 1 (each, a “Regular Distribution Date”), commencing on April 1, 2016, to the Person in whose name this Certificate is registered at the close of business
on the 15th day preceding the Regular Distribution Date, an amount in respect of the Scheduled Payments on the Series B Equipment Notes due on such Regular Distribution Date, the receipt of which has been confirmed by the Trustee, equal to the 

 

	† 	To be included on the face of each Global Certificate. 

  
 Trust Supplement No.
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product of the percentage interest in the Trust evidenced by this Certificate and an amount equal to the sum of such Scheduled Payments. Subject to and in accordance with the terms of the
Agreement and the Intercreditor Agreement, in the event that Special Payments on the Series B Equipment Notes are received by the Trustee, from funds then available to the Trustee, there shall be distributed on the applicable Special Distribution
Date, to the Person in whose name this Certificate is registered at the close of business on the 15th day preceding the applicable Special Distribution Date, an amount in respect of such Special Payments on the Series B Equipment Notes, the receipt
of which has been confirmed by the Trustee, equal to the product of the percentage interest in the Trust evidenced by this Certificate and an amount equal to the sum of such Special Payments so received. If a Regular Distribution Date or Special
Distribution Date is not a Business Day, distribution shall be made on the immediately following Business Day and no interest shall accrue during the intervening period. The Trustee shall mail notice of each Special Payment and the Special
Distribution Date therefor to the Certificateholder of this Certificate. 
 Distributions on this Certificate will be made by the Trustee by
check mailed to the Person entitled thereto, without the presentation or surrender of this Certificate or the making of any notation hereon, except that with respect to Certificates registered on the Record Date in the name of a Clearing Agency (or
its nominee), such distributions shall be made by wire transfer. Except as otherwise provided in the Agreement and notwithstanding the above, the final distribution on this Certificate will be made after notice mailed by the Trustee of the pendency
of such distribution and only upon presentation and surrender of this Certificate at the office or agency of the Trustee specified in such notice. 

The Certificates do not represent a direct obligation of, or an obligation guaranteed by, or an interest in, the Company, the Trustee, the
Subordination Agent, any Loan Trustee or any Affiliate of any thereof. The Certificates are limited in right of payment, all as more specifically set forth on the face hereof and in the Agreement. All payments or distributions made to
Certificateholders under the Agreement shall be made only from the Trust Property and only to the extent that the Trustee shall have sufficient income or proceeds from the Trust Property to make such payments in accordance with the terms of the
Agreement. Each Certificateholder of this Certificate, by its acceptance hereof, agrees that it will look solely to the income and proceeds from the Trust Property to the extent available for any payment or distribution to such Certificateholder
pursuant to the terms of the Agreement and that it will not have any recourse to the Company, the Trustee, the Loan Trustees or any Affiliate of any thereof except as otherwise expressly provided in the Agreement, in any Note Document or in the
Intercreditor Agreement. This Certificate does not purport to summarize the Agreement and reference is made to the Agreement for information with respect to the interests, rights, benefits, obligations, proceeds and duties evidenced hereby. A copy
of the Agreement may be examined during normal business hours at the principal office of the Trustee, and at such other places, if any, designated by the Trustee, by any Certificateholder upon request. 

The Agreement permits, with certain exceptions therein provided, the amendment thereof, and the modification of the rights and obligations of
the Company and the rights of the Certificateholders under the Agreement, at any time by the Company and the Trustee with the consent of the Certificateholders holding Certificates evidencing Fractional Undivided Interests aggregating not less than
a majority in interest in the Trust. Any such consent by the Certificateholder of this Certificate shall be conclusive and binding on such Certificateholder and upon all future Certificateholders of this Certificate and of any Certificate issued
upon the transfer hereof or in exchange hereof or in lieu hereof whether or not notation of such consent is made upon this Certificate. The Agreement also permits the amendment thereof, in certain limited circumstances, without the consent of the
Certificateholders of any of the Certificates. 
 As provided in the Agreement and subject to certain limitations set forth therein, the
transfer of this Certificate is registrable in the Register upon surrender of this Certificate for registration 

  
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of transfer at the offices or agencies maintained by the Trustee in its capacity as Registrar, or by any successor Registrar, duly endorsed or accompanied by a written instrument of transfer in
form satisfactory to the Trustee and the Registrar, duly executed by the Certificateholder hereof or such Certificateholder’s attorney duly authorized in writing, and thereupon one or more new Certificates of authorized denominations evidencing
the same aggregate Fractional Undivided Interest in the Trust will be issued to the designated transferee or transferees. 
 The
Certificates are issuable only as registered Certificates without coupons in minimum denominations of $2,000 (or such other denomination that is the lowest integral multiple of $1,000 that is, at the time of issuance, equal to at least 1,000 euros)
Fractional Undivided Interest and integral multiples of $1,000 in excess thereof except that one Certificate may be issued in a different denomination. As provided in the Agreement and subject to certain limitations therein set forth, the
Certificates are exchangeable for new Certificates of authorized denominations evidencing the same aggregate Fractional Undivided Interest in the Trust, as requested by the Certificateholder surrendering the same. 

No service charge will be made for any such registration of transfer or exchange, but the Trustee shall require payment of a sum sufficient to
cover any tax or governmental charge payable in connection therewith. 
 The Company, the Trustee, the Registrar and any Paying Agent shall
deem and treat the Person in whose name this Certificate is registered as the owner hereof for all purposes, and none of the Company, the Trustee, the Registrar or any such agent shall be affected by any notice to the contrary. 

Each Certificateholder and Person with a beneficial interest herein, by its acceptance of this Certificate or such interest, agrees to treat
the Trust as a grantor trust for all U.S. federal, state and local income tax purposes. 
 The obligations and responsibilities created by
the Agreement and the Trust created thereby shall terminate upon the distribution to Certificateholders of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust
Property. 
 Any Person acquiring or accepting this Certificate or an interest herein will, by such acquisition or acceptance, be deemed to
(a) represent and warrant to the Company, the Loan Trustees and the Trustee that either: (i) no assets of a Plan or any trust established with respect to a Plan have been used to purchase or hold this Certificate or an interest herein or
(ii) the purchase and holding of this Certificate or interest herein by such Person are exempt from the prohibited transaction restrictions of ERISA and the Code or provisions of Similar Law pursuant to one or more prohibited transaction
statutory or administrative exemptions or similar exemptions under Similar Law and (b) direct the Trustee to invest the assets held in the Trust pursuant to, and take all other actions contemplated by, the terms and conditions of the Basic
Agreement, this Trust Supplement, the Intercreditor Agreement, the Deposit Agreement, the Escrow Agreement, the NPA, and each Participation Agreement. 

THIS CERTIFICATE AND THE AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK, INCLUDING ALL
MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE. 
 Unless the certificate of authentication hereon has been executed by the Trustee,
by manual signature, this Certificate shall not be entitled to any benefit under the Agreement or be valid for any purpose. 

  
 Trust Supplement No.
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 IN WITNESS WHEREOF, the Trustee has caused this Certificate to be duly executed. 

 

			
	SPIRIT AIRLINES PASS THROUGH TRUST 2015-1B
		
	By:	 	WILMINGTON TRUST, NATIONAL ASSOCIATION,
		 	as Trustee
		
	By:	 	  

		 	Title:

 Dated: 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 TRUSTEE’S CERTIFICATE OF AUTHENTICATION 

This is one of the Certificates referred to in the within-mentioned Agreement. 

 

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION,
	as Trustee
		
	By:	 	  

		 	Authorized Officer

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 [FORM OF TRANSFER NOTICE] 

FOR VALUE RECEIVED the undersigned registered holder hereby sell(s), assign(s) and transfer(s) unto 

 

			
	Insert Taxpayer Identification No.	  	
		
	  
	  	

 Please print or typewrite name and address including zip code of assignee 

 

			
	
                     
                                   
	  	

 the within Certificate and all rights thereunder, hereby irrevocably constituting and appointing
                     attorney to transfer said Certificate on the books of the Trustee with full power of substitution in the premises. 

 

									
	Date:	 	  
	 		 	  
	 	
		 		 		 	NOTICE: The signature to this assignment must correspond with the name as written upon the face of the within-mentioned instrument in every particular, without alteration or any change whatsoever.
					
		 		 		 	SIGNATURE GUARANTEE:	 	  

 Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirements of the
Registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Registrar in addition to, or in
substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended. 

  
 Trust Supplement No.
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 (Spirit 2015-1 EETC) 

 EXHIBIT B to 

TRUST SUPPLEMENT NO. 2015-1B 

DTC LETTER OF REPRESENTATIONS 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 EXHIBIT C to 

TRUST SUPPLEMENT NO. 2015-1B 

AMENDMENTS TO BASIC AGREEMENT 
 Part A

 Section 5.02. Consolidation, Merger, Etc. The Company shall not consolidate with or merge into any other
Person or convey, transfer or lease substantially all of its assets as an entirety to any Person, unless: 
 (i) the
successor or transferee entity shall, if and to the extent required under Section 1110 in order that any Loan Trustee continues to be entitled to any benefits of Section 1110 with respect to any Aircraft, be a holder of an air carrier
operating certificate issued by the Secretary of Transportation pursuant to Chapter 447 of Title 49 of the United States Code for aircraft capable of carrying ten or more individuals or 6,000 pounds or more of cargo, and shall execute and deliver to
the Trustee an agreement containing the express assumption by such successor or transferee entity of the due and punctual performance and observance of each covenant and condition of the Note Documents, the NPA and this Agreement to be performed or
observed by the Company; and 
 (ii) the Company shall deliver to the Trustee a certificate signed by a Responsible Officer
of the Company stating that such consolidation, merger, conveyance, transfer or lease and the assumption agreement mentioned in clause (i) above comply with this Section 5.02. 

Upon any consolidation or merger, or any conveyance, transfer or lease of substantially all of the assets of the Company as an
entirety in accordance with this Section 5.02, the successor Person formed by such consolidation or into which the Company is merged or to which such conveyance, transfer or lease is made shall succeed to, and be substituted for, and may
exercise every right and power of, the Company under the Note Documents, the NPA and this Agreement with the same effect as if such successor Person had been named as the Company herein. 

Part B 
 Section 6.07.
Certificateholders May Not Bring Suit Except Under Certain Conditions. A Certificateholder of any series shall not have the right to institute any suit, action or proceeding at law or in equity or otherwise with respect to this Agreement, the
related Trust Supplement or the Certificates or otherwise, or for the appointment of a receiver or for the enforcement of any other remedy under this Agreement, the related Trust Supplement or the Certificates or otherwise, unless: 

 

	 	(1)	such Certificateholder previously shall have given written notice to the Trustee of a continuing Event of Default; 

  

	 	(2)	Certificateholders holding Certificates of such series evidencing Fractional Undivided Interests aggregating not less than 25% of the related Trust shall have requested the Trustee in writing to institute such action,
suit or proceeding and shall have offered to the Trustee indemnity as provided in Section 7.03(e); 

  

	 	(3)	the Trustee shall have refused or neglected to institute any such action, suit or proceeding for 60 days after receipt of such notice, request and offer of indemnity; and 

 

	 	(4)	no Direction inconsistent with such written request shall have been given to the Trustee during such 60-day period by either Certificateholders holding Certificates of such series evidencing Fractional Undivided
Interests aggregating not less than a majority in interest in the related Trust or the Controlling Party under the related Intercreditor Agreement. 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 Except to the extent provided in any applicable Intercreditor Agreement or in any
applicable Trust Supplement, it is understood and intended that no one or more of the Certificateholders of any series shall have any right in any manner whatsoever hereunder or under the related Trust Supplement or under the Certificates of such
series to (i) surrender, impair, waive, affect, disturb or prejudice any property in the Trust Property of the related Trust, or the lien of any related Indenture on any property subject thereto, or the rights of the Certificateholders of such
series or the holders of the related Equipment Notes, (ii) obtain or seek to obtain priority over or preference with respect to any other such Certificateholder of such series or (iii) enforce any right under this Agreement, the related
Trust Supplement or under the Certificates of such series, except in the manner provided in this Agreement and for the equal, ratable and common benefit of all the Certificateholders of such series. 

Part C 
 Provided that
there is a bank or trust company in a U.S. jurisdiction where there are no Avoidable Taxes that is willing to act as Trustee and is eligible to act as Trustee under Section 7.08 and the applicable provisions of any Trust Supplement, the Company
shall promptly appoint a successor Trustee of such Trust in a jurisdiction where there are no Avoidable Taxes. 
 Part D 

(a) file with the Trustee, within 30 days after the Company files the same with the SEC, copies of the annual reports and of
the information, documents and other reports (or copies of such portions of any of the foregoing as the SEC may from time to time by rules and regulations prescribe) which the Company is required to file with the SEC pursuant to Section 13 or
Section 15(d) of the Securities Exchange Act of 1934, as amended; or, if the Company is not required to file information, documents or reports pursuant to either of such sections, then to file with the Trustee and the SEC, in accordance with
rules and regulations prescribed by the SEC, such supplementary and periodic information, documents and reports which may be required pursuant to Section 13 of the Securities Exchange Act of 1934, as amended, in respect of a security listed and
registered on a national securities exchange as may be prescribed in such rules and regulations; 
 Part E 

(4) (A) to cure any ambiguity or to correct any mistake or inconsistency contained in this Basic Agreement or in any related
Trust Supplement, any Intercreditor Agreement or any Liquidity Facility; or (B) to make or modify any other provision in regard to matters or questions arising under this Basic Agreement or any related Trust Supplement, any Intercreditor
Agreement or any Liquidity Facility as the Company may deem necessary or desirable and that will not materially adversely affect the interests of the related Certificateholders; or (C) to correct or supplement the description of any property
constituting property of any Trust or the description of any Aircraft, and to reflect the substitution of another aircraft for any Aircraft; or 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 Part F 

Section 12.01. Limitation on Rights of Certificateholders. (a) The insolvency, death or incapacity of any
Certificateholder of any series shall not operate to terminate this Agreement or the related Trust, nor entitle such Certificateholder’s legal representative or heirs to claim an accounting or to take any action or commence any proceeding in
any court for a partition or winding up of the Trust, nor otherwise affect the rights, obligations and liabilities of the parties hereto or any of them. No Certificateholder of any series shall be entitled to revoke the related Trust. 

(b) No transfer, by operation of law or otherwise, of any Certificate or other right, title and interest of any
Certificateholder in and to the applicable Trust Property or under the related Trust shall operate to terminate the Trust or entitle such Certificateholder or any successor or transferee of such Certificateholder to an accounting or to the transfer
to it of legal title to any part of such Trust Property. 
 Part G 

Section 12.02. Liabilities of Certificateholders. The Certificateholders of each series shall not be personally
liable for obligations of the related Trust, the Fractional Undivided Interests represented by the Certificates of such series shall be nonassessable for any losses or expenses of such Trust or for any reason whatsoever, and the Certificates of such
series upon authentication thereof by the Trustee pursuant to Section 3.02 are and shall be deemed fully paid. No Certificateholder of such series shall have any right (except as expressly provided herein) to vote or in any manner otherwise
control the operation and management of the related Trust Property, the related Trust, or the obligations of the parties hereto, nor shall anything set forth herein, or contained in the terms of the Certificates of such series, be construed so as to
constitute the Certificateholders of such series from time to time as partners or members of an association. 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 SCHEDULE I to 

TRUST SUPPLEMENT NO. 2015-1B 

SERIES B EQUIPMENT NOTES, 

PRINCIPAL AMOUNTS, MATURITIES AND AIRCRAFT 
  

									
	Initial Principal
Amount of Series B
Equipment
Notes*	 	 	Maturity	 	Aircraft**	 	Manufacturer Serial
Number**
	$	7,221,000.00	  	 	April 1, 2024	 	N644NK	 	TBD
	 	7,197,000.00	  	 	April 1, 2024	 	N645NK	 	TBD
	 	7,173,000.00	  	 	April 1, 2024	 	N646NK	 	TBD
	 	8,356,000.00	  	 	April 1, 2024	 	N660NK	 	6804
	 	8,336,000.00	  	 	April 1, 2024	 	N661NK	 	6867
	 	8,316,000.00	  	 	April 1, 2024	 	N662NK	 	6897
	 	8,307,000.00	  	 	April 1, 2024	 	N663NK	 	TBD
	 	8,288,000.00	  	 	April 1, 2024	 	N664NK	 	TBD
	 	8,288,000.00	  	 	April 1, 2024	 	N665NK	 	TBD
	 	8,299,000.00	  	 	April 1, 2024	 	N667NK	 	TBD
	 	8,279,000.00	  	 	April 1, 2024	 	N668NK	 	TBD
	 	8,249,000.00	  	 	April 1, 2024	 	N669NK	 	TBD
	 	8,230,000.00	  	 	April 1, 2024	 	N670NK	 	TBD
	 	8,220,000.00	  	 	April 1, 2024	 	N671NK	 	TBD
	 	8,200,000.00	  	 	April 1, 2024	 	N672NK	 	TBD

  

	*	Subject to adjustment as provided in the NPA. 

	**	Subject to substitution as provided in the NPA. 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC) 

 SCHEDULE II to 

TRUST SUPPLEMENT NO. 2015-1B 

NOTE DOCUMENTS 

Participation Agreement 
 Indenture

 Manufacturer’s Consent (as defined in any applicable Indenture) 

For each of the aircraft listed in Schedule I. 

  
 Trust Supplement No.
2015-1B 
 (Spirit 2015-1 EETC)Revolving Credit Agreement (2015-1A)

 Exhibit 4.4 

EXECUTION VERSION 
  

 
  

REVOLVING CREDIT AGREEMENT 

(2015-1A) 
 Dated as of
August 11, 2015 
 between 

WILMINGTON TRUST, NATIONAL ASSOCIATION, 

as Subordination Agent, 
 as agent
and trustee for the trustee of 
 Spirit Airlines Pass Through Trust 2015-1A, 

as Borrower 
 and 

NATIXIS, ACTING VIA ITS NEW YORK BRANCH 

as Liquidity Provider 
 Spirit
Airlines Pass Through Trust 2015-1A 
 Spirit Airlines 

Pass Through Certificates, 
 Series
2015-1A 
  
  

 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 Table of Contents 

 

							
	 	 	 	  	Page	 
		
	 ARTICLE I DEFINITIONS
	  	 	1	  
			
	 Section 1.01
	 	 Definitions
	  	 	1	  
		
	 ARTICLE II AMOUNT AND TERMS OF THE COMMITMENT
	  	 	11	  
			
	 Section 2.01
	 	 The Advances
	  	 	11	  
			
	 Section 2.02
	 	 Making of Advances
	  	 	11	  
			
	 Section 2.03
	 	 Fees
	  	 	13	  
			
	 Section 2.04
	 	 Reduction or Termination of the Maximum Commitment
	  	 	13	  
			
	 Section 2.05
	 	 Repayments of Interest Advances, the Special Termination Advance or the Final Advance
	  	 	14	  
			
	 Section 2.06
	 	 Repayments of Provider Advances
	  	 	15	  
			
	 Section 2.07
	 	 Payments to the Liquidity Provider Under the Intercreditor Agreement
	  	 	16	  
			
	 Section 2.08
	 	 Book Entries
	  	 	16	  
			
	 Section 2.09
	 	 Payments from Available Funds Only
	  	 	16	  
			
	 Section 2.10
	 	 Extension of the Expiry Date; Non-Extension Advance
	  	 	17	  
		
	 ARTICLE III OBLIGATIONS OF THE BORROWER
	  	 	17	  
			
	 Section 3.01
	 	 Increased Costs
	  	 	17	  
			
	 Section 3.02
	 	 Reserved
	  	 	18	  
			
	 Section 3.03
	 	 Withholding Taxes
	  	 	19	  
			
	 Section 3.04
	 	 Payments
	  	 	20	  
			
	 Section 3.05
	 	 Computations
	  	 	20	  
			
	 Section 3.06
	 	 Payment on Non-Business Days
	  	 	21	  

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 i 

							
			
	 Section 3.07
	 	 Interest
	  	 	21	  
			
	 Section 3.08
	 	 Replacement of Borrower
	  	 	23	  
			
	 Section 3.09
	 	 Funding Loss Indemnification
	  	 	23	  
			
	 Section 3.10
	 	 Illegality
	  	 	23	  
		
	 ARTICLE IV CONDITIONS PRECEDENT
	  	 	24	  
			
	 Section 4.01
	 	 Conditions Precedent to Effectiveness of Section 2.01
	  	 	24	  
			
	 Section 4.02
	 	 Conditions Precedent to Borrowing
	  	 	25	  
		
	 ARTICLE V COVENANTS
	  	 	26	  
			
	 Section 5.01
	 	 Affirmative Covenants of the Borrower
	  	 	26	  
			
	 Section 5.02
	 	 Negative Covenants of the Borrower
	  	 	26	  
		
	 ARTICLE VI LIQUIDITY EVENTS OF DEFAULT AND SPECIAL TERMINATION
	  	 	27	  
			
	 Section 6.01
	 	 Liquidity Events of Default
	  	 	27	  
		
	 ARTICLE VII MISCELLANEOUS
	  	 	27	  
			
	 Section 7.01
	 	 No Oral Modifications or Continuing Waivers
	  	 	27	  
			
	 Section 7.02
	 	 Notices
	  	 	28	  
			
	 Section 7.03
	 	 No Waiver; Remedies
	  	 	29	  
			
	 Section 7.04
	 	 Further Assurances
	  	 	29	  
			
	 Section 7.05
	 	 Indemnification; Survival of Certain Provisions
	  	 	29	  
			
	 Section 7.06
	 	 Liability of the Liquidity Provider
	  	 	29	  
			
	 Section 7.07
	 	 Certain Costs and Expenses
	  	 	30	  
			
	 Section 7.08
	 	 Binding Effect; Participations
	  	 	30	  
			
	 Section 7.09
	 	 Severability
	  	 	31	  
			
	 Section 7.10
	 	 Governing Law
	  	 	32	  

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 ii 

							
			
	 Section 7.11
	 	 Submission to Jurisdiction; Waiver of Jury Trial; Waiver of Immunity
	  	 	32	  
			
	 Section 7.12
	 	 Counterparts
	  	 	33	  
			
	 Section 7.13
	 	 Entirety
	  	 	33	  
			
	 Section 7.14
	 	 Headings
	  	 	33	  
			
	 Section 7.15
	 	 Liquidity Provider’s Obligation to Make Advances
	  	 	33	  
			
	 Section 7.16
	 	 Head Office Obligations
	  	 	33	  

  

					
	 Annex I
	 	-	 	 Form of Interest Advance Notice of Borrowing

	 Annex II
	 	-	 	 Form of Non-Extension Advance Notice of Borrowing

	 Annex III
	 	-	 	 Form of Downgrade Advance Notice of Borrowing

	 Annex IV
	 	-	 	 Form of Final Advance Notice of Borrowing

	 Annex V
	 	-	 	 Form of Special Termination Advance Notice of Borrowing

	 Annex VI
	 	-	 	 Form of Notice of Termination

	 Annex VII
	 	-	 	 Form of Notice of Special Termination

	 Annex VIII
	 	-	 	 Form of Notice of Replacement Subordination Agent

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 iii 

 REVOLVING CREDIT AGREEMENT 

(2015-1A) 

This REVOLVING CREDIT AGREEMENT (2015-1A), dated as of August 11, 2015, is made by and between WILMINGTON TRUST, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but solely as Subordination Agent (such term and other capitalized terms used herein without definition being defined as provided in Article I) under the Intercreditor
Agreement (as defined below), as agent and trustee for the Class A Trustee (in such capacity, together with its successors in such capacity, the “Borrower”), and NATIXIS (“Natixis”), a French
société anonyme, acting via its New York Branch (the “Liquidity Provider”). 
 W
I T N E S S E T H: 
 WHEREAS, pursuant to the Class A Trust Agreement,
the Class A Trust is issuing the Class A Certificates; and 
 WHEREAS, the Borrower, in order to support the timely payment of a
portion of the interest on the Class A Certificates in accordance with their terms, has requested the Liquidity Provider to enter into this Agreement, providing in part for the Borrower to request in specified circumstances that Advances be
made hereunder; 
 NOW, THEREFORE, in consideration of the mutual agreements herein contained, and of other good and valuable consideration
the receipt and adequacy of which are hereby acknowledged, the parties hereto agree as follows: 
 ARTICLE I 

DEFINITIONS 
 Section 1.01
Definitions. (a) The definitions stated herein apply equally to both the singular and the plural forms of the terms defined. 

(b) All references in this Agreement to designated “Articles”, “Sections”, “Annexes” and other subdivisions are
to the designated Article, Section, Annex or other subdivision of this Agreement, unless otherwise specifically stated. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 (c) The words “herein”, “hereof” and “hereunder” and other words of
similar import refer to this Agreement as a whole and not to any particular Article, Section, Annex or other subdivision. 
 (d) Unless the
context otherwise requires, whenever the words “including”, “include” or “includes” are used herein, it shall be deemed to be followed by the phrase “without limitation”. 

(e) All references in this Agreement to a Person shall include successors and permitted assigns of such Person. 

(f) For the purposes of this Agreement, unless the context otherwise requires, the following capitalized terms shall have the following
meanings: 
 “Advance” means an Interest Advance, a Final Advance, a Provider Advance, an Unapplied Provider
Advance, an Applied Provider Advance, a Special Termination Advance, an Applied Special Termination Advance or an Unpaid Advance, as the case may be. 

“Agreement” means this Agreement, as the same may be amended, supplemented or otherwise modified from time to time in
accordance with its terms. 
 “Applicable Liquidity Rate” has the meaning specified in Section 3.07(h). 

“Applicable Margin” means (a) with respect to any Interest Advance, Final Advance, Applied Provider Advance or
Applied Special Termination Advance, 3.25% per annum, (b) with respect to any Unapplied Provider Advance, the rate per annum specified in the Fee Letter or (c) with respect to any Special Termination Advance, the rate per annum
specified in the Fee Letter. 
 “Applied Downgrade Advance” has the meaning specified in Section 2.06(a). 

“Applied Non-Extension Advance” has the meaning specified in Section 2.06(a). 

“Applied Provider Advance” means an Applied Downgrade Advance or an Applied Non-Extension Advance. 

“Applied Special Termination Advance” has the meaning specified in Section 2.05. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 2 

 “Base Rate” means a fluctuating interest rate per annum in effect from
time to time, which rate per annum shall at all times be equal to the sum of (a) the weighted average of the rates on overnight Federal funds transactions with members of the Federal Reserve System arranged by Federal funds brokers, as
published for each day in the period for which the Base Rate is to be determined (or, if such day is not a Business Day, for the preceding Business Day) by the Federal Reserve Bank of New York, or if such rate is not so published for any day that is
a Business Day, the average of the quotations for such day for such transactions received by the Liquidity Provider from three Federal funds brokers of recognized standing selected by it (and reasonably satisfactory to Spirit) plus (b) one-quarter of one percent (0.25%). 
 “Base Rate Advance” means an
Advance that bears interest at a rate based upon the Base Rate. 
 “Borrower” has the meaning specified in the
introductory paragraph to this Agreement. 
 “Borrowing” means the making of Advances requested by delivery of a
Notice of Borrowing. 
 “Business Day” means any day other than a Saturday, a Sunday or a day on which commercial
banks are required or authorized to close in New York, New York, Miramar, Florida, Wilmington, Delaware, or, so long as any Class A Certificate is outstanding, the city and state in which the Class A Trustee, the Borrower or any related
Loan Trustee maintains its Corporate Trust Office or receives or disburses funds, and, if the applicable Business Day relates to any Advance or other amount bearing interest based on the LIBOR Rate, on which dealings are carried on in the London
interbank market. 
 “Code” means the United States Internal Revenue Code of 1986, as amended. 

“Covered Taxes” means any Taxes imposed by the United States, or any political subdivision or taxing authority thereof
or therein, that are required by law to be deducted or withheld from any amounts payable to the Liquidity Provider under this Agreement other than (i) any such Tax on, based on or measured by net income, franchises or conduct of business,
(ii) any such Tax imposed, levied, withheld or assessed as a result of any connection between the Liquidity Provider and the United States or such political subdivision or taxing authority, other than a connection arising solely from the
Liquidity Provider’s having executed, delivered, performed its obligations or received a payment under, or enforced, any Operative Agreement, (iii) any such Tax attributable to the inaccuracy in or breach by the Liquidity Provider of any
of its representations, warranties or covenants contained in any Operative Agreement to which it is a party or the inaccuracy of any form, certificate or document furnished pursuant thereto, (iv) any such withholding Taxes imposed by the United
States except to the extent such withholding Taxes would not have been required to be deducted or withheld from payments 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 3 

 
hereunder but for a change after the date hereof in the Code or the Treasury Regulations thereunder that affects the exemption for income that is effectively connected with the conduct of a trade
or business within the United States, (v) any withholding Taxes imposed by the United States which are imposed or increased as a result of the Liquidity Provider failing to deliver to the Borrower any form, certificate or document (which form,
certificate or document, in the good faith judgment of the Liquidity Provider, it is legally entitled to provide) which is reasonably requested by the Borrower to establish that payments under this Agreement are exempt from (or entitled to a reduced
rate of) withholding Tax, (vi) any such Taxes that would not have been imposed but for any change in the Lending Office without the prior written consent of Spirit (such consent not to be unreasonably withheld), or (vii) any Taxes imposed
under FATCA. 
 “Downgrade Advance” means an Advance made pursuant to Section 2.02(b)(ii). 

“Downgrade Event” means any downgrading of, or any suspension or withdrawal of any applicable rating of, the Liquidity
Provider by any Rating Agency such that after such downgrading, suspension or withdrawal the Liquidity Provider does not have the minimum Long-Term Rating specified for such Rating Agency in the definition of “Threshold Rating”. The
occurrence of a Downgrade Event shall be determined separately for each Rating Agency. For the avoidance of doubt, a Downgrade Event shall not occur with respect to a Rating Agency so long as the Liquidity Provider has either of the applicable
Threshold Ratings specified for such Rating Agency. 
 “Effective Date” has the meaning specified in
Section 4.01. The delivery of the certificate of the Liquidity Provider contemplated by Section 4.01(e) shall be conclusive evidence that the Effective Date has occurred. 

“Excluded Taxes” means (a) Taxes imposed on the overall net income of the Liquidity Provider, (b) Taxes
imposed on the “effectively connected income” of its Lending Office, (c) Covered Taxes that are indemnified pursuant to Section 3.03 hereof, and (d) Taxes described in clauses (i) through (vii) in the definition of
“Covered Taxes”. 
 “Expenses” means liabilities, losses, damages, costs and expenses
(including, without limitation, reasonable fees and disbursements of legal counsel), provided that Expenses shall not include any Taxes other than sales, use and V.A.T. taxes imposed on fees and expenses payable pursuant to Section 7.07. 

“Expiry Date” means the earlier of (a) the anniversary date of the Closing Date immediately following the date on
which the Liquidity Provider has provided a Non-Extension Notice to the Borrower pursuant to Section 2.10 and (b) the 15th day after the Final Legal Distribution Date of the Class A
Certificates. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 4 

 “FATCA” means Sections 1471 through 1474 of the Code as of the date of
this Agreement (or any amended or successor provisions that are substantively comparable and not materially more onerous to comply with); any current or future regulations or official interpretations thereof; any agreements entered into pursuant to
Section 1471(b)(1) of the Code; any intergovernmental agreement entered into in connection with any of the foregoing; and any fiscal or regulatory legislation, rules or practices adopted pursuant to any such intergovernmental agreement. 

“Final Advance” means an Advance made pursuant to Section 2.02(c). 

“Head Office” has the meaning specified in Section 7.16. 

“Increased Cost” has the meaning specified in Section 3.01. 

“Intercreditor Agreement” means the Intercreditor Agreement, dated as of the date hereof, among the Trustees, the
Liquidity Provider, the liquidity provider under each Liquidity Facility (other than this Agreement), and the Subordination Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms. 

“Interest Advance” means an Advance made pursuant to Section 2.02(a). 

“Interest Period” means, with respect to any LIBOR Advance, each of the following periods: 

(i) the period beginning on the third Business Day following either (A) the Liquidity Provider’s receipt of the
Notice of Borrowing for such LIBOR Advance or (B) the date of the withdrawal of funds from the Class A Cash Collateral Account for the purpose of paying interest on the Class A Certificates as contemplated by Section 2.06(a)
hereof and, in each case, ending on the next succeeding Regular Distribution Date; and 
 (ii) each subsequent period
commencing on the last day of the immediately preceding Interest Period and ending on next succeeding Regular Distribution Date; 
 provided,
however, that if (x) the Final Advance shall have been made pursuant to Section 2.02(c) or (y) other outstanding Advances shall have been converted into the Final Advance pursuant to Section 6.01(a), then the Interest
Periods shall be successive periods of one month beginning on (A) the third Business Day following the Liquidity Provider’s receipt of the Notice of Borrowing for such Final Advance (in the case of clause (x) above) or (B) the
Regular Distribution Date following such conversion (in the case of clause (y) above). 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 5 

 “Lending Office” means the lending office of the Liquidity Provider
through which it acts for purposes of this Agreement, which is presently located at 1251 Avenue of the Americas, New York, New York 10020, or such other lending office as the Liquidity Provider from time to time shall notify the Borrower as its
lending office hereunder; provided that the Liquidity Provider shall not change its Lending Office without the prior written consent of Spirit (such consent not to be unreasonably withheld). 

“LIBOR Advance” means an Advance bearing interest at a rate based upon the LIBOR Rate. 

“LIBOR Rate” means, with respect to any Interest Period, (a) the interest rate per annum equal to the London
Interbank Offered Rate per annum administered by ICE Benchmark Administration Limited (or any other successor person which takes over administration of that rate) for Dollar deposits, which rate is displayed on the Reuters Screen LIBOR01 (or such
other page or screen as may replace such Reuters Screen) at approximately 11:00 a.m. (London time) on the day that is two Business Days prior to the first day of such Interest Period, for a period comparable to such Interest Period, or
(b) if no such rate appears on such Reuters Screen (or otherwise as aforesaid), the interest rate per annum equal to the average (rounded up, if necessary, to the nearest 1/100th of 1%) of the rates per annum at which deposits in Dollars are
offered by the Reference Banks (or, if fewer than all of the Reference Banks are quoting a rate for deposits in Dollars for the applicable period and amount, such fewer number of Reference Banks) at approximately 11:00 a.m. (London time) on the
day that is two Business Days prior to the first day of such Interest Period to prime banks in the London interbank market for a period comparable to such Interest Period and in an amount approximately equal to the principal amount of the LIBOR
Advance to be outstanding during such Interest Period, or (c) if none of the Reference Banks is quoting a rate for deposits in Dollars in the London interbank market for such a period and amount, the interest rate per annum equal to the average
(rounded up, if necessary, to the nearest 1/100th of 1%) of the rates at which deposits in Dollars are offered by the principal New York offices of the Reference Banks (or, if fewer than all of the Reference Banks are quoting a rate for deposits in
Dollars in the New York interbank market for the applicable period and amount, such fewer number of Reference Banks) at approximately 11:00 a.m. (New York time) on the day that is two Business Days prior to the first day of such Interest Period
to prime banks in the New York interbank market for a period comparable to such Interest Period and in an amount approximately equal to the principal amount of the LIBOR Advance to be outstanding during such Interest Period, or (d) if none of
the principal New York offices of the Reference Banks is quoting a rate for deposits in Dollars in the New York interbank market for the applicable period and amount, the Base Rate; provided that, if the LIBOR Rate determined as provided
above with respect to any LIBOR Advance for any Interest Period would be less than 0.50% per annum, then the LIBOR Rate with respect to such LIBOR Advance shall be deemed to be 0.50% per annum. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 6 

 “Liquidity Event of Default” means the occurrence of either (a) the
Acceleration of all of the Equipment Notes (provided that, with respect to the period prior to the Delivery Period Termination Date, the aggregate principal balance of such Equipment Notes is in excess of $350 million) or (b) a Spirit
Bankruptcy Event. 
 “Liquidity Indemnitee” means the Liquidity Provider, its directors, officers, employees and
agents, and its successors and permitted assigns. 
 “Liquidity Provider” has the meaning specified in the
introductory paragraph to this Agreement. 
 “Maximum Available Commitment” means, subject to the proviso contained
in the third sentence of Section 2.02(a), at any time of determination, (a) the Maximum Commitment at such time less (b) the aggregate amount of each Interest Advance outstanding at such time; provided that, subject to
Section 2.06(d), following a Provider Advance, a Special Termination Advance or a Final Advance, the Maximum Available Commitment shall be zero. 

“Maximum Commitment” means $30,615,268, as the same may be reduced from time to time in accordance with Section
2.04(a). 
 “Natixis” has the meaning specified in the introductory paragraph to this Agreement. 

“Non-Extension Advance” means an Advance made pursuant to Section 2.02(b)(i). 

“Non-Extension Notice” has the meaning specified in Section 2.10. 

“Notice Date” has the meaning specified in Section 2.10. 

“Notice of Borrowing” has the meaning specified in Section 2.02(e). 

“Notice of Replacement Subordination Agent” has the meaning specified in Section 3.08. 

“Participation” has the meaning specified in Section 7.08(b). 

  
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 “Performing Note Deficiency” means any time that less than 65% of the
then aggregate outstanding principal amount of all Series A Equipment Notes and Series B Equipment Notes are Performing Equipment Notes. 

“Permitted Transferee” means any Person that: 

(a) is not a commercial air carrier, Spirit or any affiliate of Spirit; and 

(b) is any one of: 

(1) a commercial banking institution organized under the laws of the United States or any state thereof or the District of
Columbia; 
 (2) a commercial banking institution that (x) is organized under the laws of France, Germany, The
Netherlands, Switzerland or the United Kingdom, (y) is entitled on the date it acquires any Participation to a complete exemption from United States federal income taxes for all income derived by it from the transactions contemplated by the
Operative Agreements under an income tax treaty, as in effect on such date, between the United States and such jurisdiction of its organization and (z) is engaged in the active conduct of a banking business in such jurisdiction of its
organization, holds its Participation in connection with such banking business in such jurisdiction and is regulated as a commercial banking institution by the appropriate regulatory authorities in such jurisdiction; or 

(3) a commercial banking institution that (x) is organized under the laws of Canada, France, Germany, Ireland, Japan,
Luxembourg, The Netherlands, Sweden, Switzerland or the United Kingdom and (y) is entitled on the date it acquires any Participation to a complete exemption from withholding of United States federal income taxes for all income derived by it
from the transactions contemplated by the Operative Agreements under laws as in effect on such date by reason of such income being effectively connected with the conduct of a trade or business within the United States. 

“Prospectus Supplement” means the Prospectus Supplement, dated July 28, 2015, relating to the Class A
Certificates and the Class B Certificates, as such Prospectus Supplement may be amended or supplemented. 
 “Provider
Advance” means a Downgrade Advance or a Non-Extension Advance. 

  
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 “Rate Determination Notice” has the meaning specified in Section
3.07(g). 
 “Reference Banks” means the principal London offices of: Natixis; Deutsche Bank AG; and JP Morgan Chase
Bank, N.A.; and such other or additional banking institutions as may be designated from time to time by mutual agreement of Spirit and the Liquidity Provider. 

“Regulatory Change” means (x) the enactment, adoption or promulgation, after the date of this Agreement, of any
law or regulation by a United States federal or state government or by any government having jurisdiction over the Liquidity Provider, or any change, after the date of this Agreement, in any such law or regulation, or in the interpretation thereof
by any governmental authority, central bank or comparable agency of the United States or any government having jurisdiction over the Liquidity Provider charged with responsibility for the administration or application thereof, that shall impose,
modify or deem applicable, or (y) the compliance by the Liquidity Provider (or its head office) with any applicable direction or requirement (whether or not having the force of law) of any central bank or competent governmental or other
authority, after the date of this Agreement, with respect to: (a) any reserve, special deposit or similar requirement against extensions of credit or other assets of, or deposits with or other liabilities of, the Liquidity Provider including,
or by reason of, the Advances, or (b) any capital adequacy requirement requiring the maintenance by the Liquidity Provider of additional capital in respect of any Advances or the Liquidity Provider’s obligation to make any such Advances,
or (c) any requirement to maintain liquidity or liquid assets in respect of the Liquidity Provider’s obligation to make any such Advances, or (d) any Taxes (other than Excluded Taxes) with respect to the amounts payable or paid
hereunder to the Liquidity Provider or any change in the basis of taxation of any amounts payable hereunder to the Liquidity Provider (other than in respect of Excluded Taxes). 

“Replenishment Amount” has the meaning specified in Section 2.06(b). 

“Required Amount” means, for any day, the sum of the aggregate amount of interest, calculated at the rate per annum
equal to the Stated Interest Rate for the Class A Certificates on the basis of a 360-day year comprised of twelve 30-day months, that would be distributable on the
Class A Certificates on each of the three successive semiannual Regular Distribution Dates immediately following such day or, if such day is a Regular Distribution Date, on such day and the succeeding two semiannual Regular Distribution Dates,
in each case calculated on the basis of the Pool Balance of the Class A Certificates on such day and without regard to expected future distributions of principal on the Class A Certificates. 

“Special Termination Advance” means an Advance made pursuant to Section 2.02(d), other than any portion of such
Advance that becomes an Applied Special Termination Advance. 

  
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 “Special Termination Notice” means the Notice of Special Termination
substantially in the form of Annex VII to this Agreement. 
 “Termination Date” means the earliest to
occur of the following: (i) the Expiry Date; (ii) the date on which the Borrower delivers to the Liquidity Provider a certificate, signed by a Responsible Officer of the Borrower, certifying that all of the Class A Certificates have
been paid in full (or provision has been made for such payment in accordance with the Intercreditor Agreement and the Class A Trust Agreement) or are otherwise no longer entitled to the benefits of this Agreement; (iii) the date on which
the Borrower delivers to the Liquidity Provider a certificate, signed by a Responsible Officer of the Borrower, certifying that a Replacement Liquidity Facility has been substituted for this Agreement in full pursuant to Section 3.05(e) of the
Intercreditor Agreement; (iv) the fifth Business Day following the receipt by the Borrower of a Termination Notice or a Special Termination Notice from the Liquidity Provider pursuant to Section 6.01(a) or 6.01(b), as applicable; and
(v) the date on which no Advance is or may (including by reason of reinstatement as herein provided) become available for a Borrowing hereunder. 

“Termination Notice” means the Notice of Termination substantially in the form of Annex VI to this Agreement.

 “Unapplied Downgrade Advance” means any Downgrade Advance other than an Applied Downgrade Advance. 

“Unapplied Non-Extension Advance” means any Non-Extension Advance other than an Applied Non-Extension Advance. 

“Unapplied Provider Advance” means any Provider Advance other than an Applied Provider Advance. 

“Unpaid Advance” has the meaning specified in Section 2.05. 

For the purposes of this Agreement, the following terms shall have the respective meanings specified in the Intercreditor Agreement: 

“Acceleration”, “Additional Certificates”, “Certificate”, “Class A Cash Collateral Account”,
“Class A Certificates”, “Class A Certificateholders”, “Class A Trust”, “Class A Trust Agreement”, “Class A Trustee”, “Class B Certificates”, “Closing
Date”, “Collection Account”, “Corporate Trust Office”, “Delivery Period Termination Date”, “Distribution Date”, “Dollars”, “Downgraded Facility”, “Equipment Notes”, “Fee
Letter”, “Final Legal Distribution Date”, 

  
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“Indenture”, “Interest Payment Date”, “Investment Earnings”, “Liquidity Facility”, “Loan Trustee”, “Long-Term Rating”,
“Non-Extended Facility”, “Note Purchase Agreement”, “Operative Agreements”, “Participation Agreements”, “Performing Equipment Note”, “Person”, “Pool Balance”, “Rating
Agencies”, “Regular Distribution Date”, “Replacement Liquidity Facility”, “Responsible Officer”, “Scheduled Payment”, “Series A Equipment Notes”, “Series B Equipment Notes”,
“Special Payment”, “Spirit”, “Spirit Bankruptcy Event”, “Stated Interest Rate”, “Subordination Agent”, “Taxes”, “Threshold Rating”, “Trust Agreement”,
“Trustee”, “Underwriters”, “Underwriting Agreement”, and “United States”. 
 ARTICLE II 

AMOUNT AND TERMS OF THE COMMITMENT 

Section 2.01 The Advances. The Liquidity Provider hereby irrevocably agrees, on the terms and conditions hereinafter set forth, to
make Advances to the Borrower from time to time on any Business Day during the period from the Effective Date until 12:00 noon (New York City time) on the Expiry Date (unless the obligations of the Liquidity Provider shall be earlier terminated in
accordance with the terms of Section 2.04(b)) in an aggregate amount at any time outstanding not to exceed the Maximum Commitment. 

Section 2.02 Making of Advances. (a) Each Interest Advance shall be made by the Liquidity Provider upon delivery to the
Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex I, signed by a Responsible Officer of the Borrower, such Interest Advance to be in an amount not exceeding the Maximum Available Commitment
at such time and used solely for the payment when due of interest with respect to the Class A Certificates at the Stated Interest Rate therefor in accordance with Section 3.05(a) and 3.05(b) of the Intercreditor Agreement. Each Interest
Advance made hereunder shall automatically reduce the Maximum Available Commitment and the amount available to be borrowed hereunder by subsequent Advances by the amount of such Interest Advance (subject to reinstatement as provided in the next
sentence). Upon repayment to the Liquidity Provider in full or in part of the amount of any Interest Advance made pursuant to this Section 2.02(a), together with accrued interest thereon (as provided herein), the Maximum Available Commitment
shall be reinstated by an amount equal to the amount of such Interest Advance so repaid, but not to exceed the Maximum Commitment; provided, however, that the Maximum Available Commitment shall not be so reinstated at any time if
(x) both a Performing Note Deficiency exists and a Liquidity Event of Default shall have occurred and be continuing or (y) a Final Advance, a Downgrade Advance, a Non-Extension Advance or a Special Termination Advance shall have occurred,
except as provided in Section 2.06(d) with respect to a Downgrade Drawing. 
 (b) (i) A Non-Extension Advance shall be made by the
Liquidity Provider in a single Borrowing if this Agreement is not extended in accordance with Section 3.05(d) of the 

  
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Intercreditor Agreement unless a Replacement Liquidity Facility to replace this Agreement shall have been previously delivered to the Borrower in accordance with said Section 3.05(d), upon
delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex II, signed by a Responsible Officer of the Borrower, in an amount equal to the Maximum Available Commitment at such time, and
shall be used to fund the Class A Cash Collateral Account in accordance with Sections 3.05(d) and 3.05(f) of the Intercreditor Agreement. 

(ii) A Downgrade Advance shall be made by the Liquidity Provider in a single Borrowing upon this Liquidity Facility becoming a Downgraded
Facility (as provided for in Section 3.05(c) of the Intercreditor Agreement) unless a Replacement Liquidity Facility to replace this Agreement shall have been previously delivered to the Borrower in accordance with said Section 3.05(c),
upon delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex III, signed by a Responsible Officer of the Borrower, in an amount equal to the Maximum Available Commitment at such
time, and shall be used to fund the Class A Cash Collateral Account in accordance with Sections 3.05(c) and 3.05(f) of the Intercreditor Agreement. 

(c) A Final Advance shall be made by the Liquidity Provider in a single Borrowing following the receipt by the Borrower of a Termination
Notice from the Liquidity Provider pursuant to Section 6.01(a) upon delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex IV, signed by a Responsible Officer of the Borrower,
in an amount equal to the Maximum Available Commitment at such time, and shall be used to fund the Class A Cash Collateral Account in accordance with Sections 3.05(f) and 3.05(i) of the Intercreditor Agreement. 

(d) A Special Termination Advance shall be made in a single Borrowing upon the receipt by the Borrower of a Special Termination Notice from
the Liquidity Provider pursuant to Section 6.01(b), by delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex V, signed by a Responsible Officer of the Borrower, in an amount
equal to the Maximum Available Commitment at such time, and shall be used to fund the Class A Cash Collateral Account in accordance with Section 3.05(f) and Section 3.05(k) of the Intercreditor Agreement. 

(e) Each Borrowing shall be made by notice in writing (a “Notice of Borrowing”) in substantially the form required by
Section 2.02(a), 2.02(b), 2.02(c) or 2.02(d), as the case may be, given by the Borrower to the Liquidity Provider. If a Notice of Borrowing is delivered by the Borrower in respect of any Borrowing no later than 12:30 p.m. (New York City
time) on a Business Day, upon satisfaction of the conditions precedent set forth in Section 4.02 with respect to such requested Borrowing, the Liquidity Provider shall make available to the Borrower, in accordance with its payment instructions,
the amount of such Borrowing in Dollars and immediately available funds, before 4:00 p.m. (New York City time) on such Business Day 

  
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or before 12:30 p.m. (New York City time) on such later Business Day specified in such Notice of Borrowing. If a Notice of Borrowing is delivered by the Borrower in respect of any Borrowing
after 12:30 p.m. (New York City time) on a Business Day, upon satisfaction of the conditions precedent set forth in Section 4.02 with respect to such requested Borrowing, the Liquidity Provider shall make available to the Borrower, in
accordance with its payment instructions, the amount of such Borrowing in Dollars and immediately available funds, before 1:00 p.m. (New York City time) on the first Business Day next following the day of receipt of such Notice of Borrowing or
on such later Business Day specified by the Borrower in such Notice of Borrowing. Payments of proceeds of a Borrowing shall be made by wire transfer of immediately available funds to the Borrower in accordance with such wire transfer instructions as
the Borrower shall furnish from time to time to the Liquidity Provider for such purpose. Each Notice of Borrowing shall be irrevocable and binding on the Borrower. Each Notice of Borrowing shall be effective upon delivery of a copy thereof to the
Liquidity Provider at the address and in the manner specified in Section 7.02 hereof. 
 (f) Upon the making of any Advance requested
pursuant to a Notice of Borrowing in accordance with the Borrower’s payment instructions, the Liquidity Provider shall be fully discharged of its obligation hereunder with respect to such Notice of Borrowing, and the Liquidity Provider shall
not thereafter be obligated to make any further Advances hereunder in respect of such Notice of Borrowing to the Borrower or to any other Person (including the Class A Trustee or any Class A Certificateholder). If the Liquidity Provider
makes an Advance requested pursuant to a Notice of Borrowing before 12:00 noon (New York City time) on the second Business Day after the date of payment specified in Section 2.02(e), the Liquidity Provider shall have fully discharged its
obligations hereunder with respect to such Advance and an event of default shall not have occurred hereunder. Following the making of any Advance pursuant to Section 2.02(b), 2.02(c) or 2.02(d) to fund the Class A Cash Collateral Account,
the Liquidity Provider shall have no interest in or rights to the Class A Cash Collateral Account, such Advance or any other amounts from time to time on deposit in the Class A Cash Collateral Account; provided that the foregoing
shall not affect or impair the obligations of the Subordination Agent to make the distributions contemplated by Section 3.05(e) or 3.05(f) of the Intercreditor Agreement. By paying to the Borrower proceeds of Advances requested by the Borrower
in accordance with the provisions of this Agreement, the Liquidity Provider makes no representation as to, and assumes no responsibility for, the correctness or sufficiency for any purpose of the amount of the Advances so made and requested. 

Section 2.03 Fees. The Borrower agrees to pay to the Liquidity Provider the fees set forth in the Fee Letter. 

Section 2.04 Reduction or Termination of the Maximum Commitment. (a) Automatic Reduction. Promptly following each date
on which the Required Amount is reduced as a result of a reduction in the Pool Balance of the Class A Certificates, the Maximum Commitment shall automatically be reduced to an amount equal to such reduced Required Amount (as calculated by the
Borrower). The Borrower shall give notice of any such automatic reduction of the Maximum 

  
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Commitment to the Liquidity Provider and Spirit within two Business Days thereof. The failure by the Borrower to furnish any such notice shall not affect any such automatic reduction of the
Maximum Commitment. 
 (b) Termination. Upon the making of any Provider Advance or Special Termination Advance or the making of or
conversion to a Final Advance hereunder or the occurrence of the Termination Date, the obligation of the Liquidity Provider to make further Advances hereunder shall automatically and irrevocably terminate, and the Borrower shall not be entitled to
request any further Borrowing hereunder, except in the case of a Downgrade Advance, as provided in Section 2.06(d). 

Section 2.05 Repayments of Interest Advances, the Special Termination Advance or the Final Advance. Subject to Sections 2.06, 2.07
and 2.09 hereof, the Borrower hereby agrees, without notice of an Advance or demand for repayment from the Liquidity Provider (which notice and demand are hereby waived by the Borrower), to pay, or to cause to be paid, to the Liquidity Provider
(a) on each date on which the Liquidity Provider shall make an Interest Advance, the Special Termination Advance or the Final Advance, an amount equal to the amount of such Advance (any such Advance, until repaid, is referred to herein as an
“Unpaid Advance”), plus (b) interest on the amount of each such Unpaid Advance in the amounts and on the dates determined as provided in Section 3.07; provided that if (i) the Liquidity Provider shall
make a Provider Advance at any time after making one or more Interest Advances which shall not have been repaid in accordance with this Section 2.05 or (ii) this Liquidity Facility shall become a Downgraded Facility or Non-Extended
Facility at any time when unreimbursed Interest Advances have reduced the Maximum Available Commitment to zero, then such Interest Advances shall cease to constitute Unpaid Advances and shall be deemed to have been changed into an Applied Downgrade
Advance or an Applied Non-Extension Advance, as the case may be, for all purposes of this Agreement (including, without limitation, for the purpose of determining when such Interest Advance is required to be repaid to the Liquidity Provider in
accordance with Section 2.06 and for the purposes of Section 2.06(b)); provided, further, that amounts in respect of a Special Termination Advance withdrawn from the Class A Cash Collateral Account for the purpose of
paying interest on the Class A Certificates in accordance with Section 3.05(f) of the Intercreditor Agreement (the portion of the outstanding Special Termination Advance equal to the amount of any such withdrawal, but not in excess of the
outstanding Special Termination Advance, being an “Applied Special Termination Advance”) shall thereafter (subject to Section 2.06(b)) be treated as an Interest Advance under this Agreement for purposes of determining
the Applicable Liquidity Rate for interest payable thereon; provided, further, that if, following the making of a Special Termination Advance, the Liquidity Provider delivers a Termination Notice to the Borrower pursuant to
Section 6.01(a), such Special Termination Advance (including any portion thereof that is an Applied Special Termination Advance) shall thereafter be treated as a Final Advance under this Agreement for purposes of determining the Applicable
Liquidity Rate for interest payable thereon; and, provided, further, that if, after making a Provider Advance, the Liquidity Provider delivers a Special Termination Notice to the Borrower pursuant to Section 6.01(b), any Unapplied
Provider Advance shall be converted to and treated as a Special Termination Advance under this Agreement for purposes of determining 

  
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the Applicable Liquidity Rate for interest payable thereon and the obligation for repayment thereof under the Intercreditor Agreement. The Borrower and the Liquidity Provider agree that the
repayment in full of each Interest Advance, Special Termination Advance and Final Advance on the date such Advance is made is intended to be a contemporaneous exchange for new value given to the Borrower by the Liquidity Provider. For the avoidance
of doubt, interest payable on an Interest Advance, Special Termination Advance or the Final Advance shall not be regarded as overdue unless such interest is not paid when due under Section 3.07. 

Section 2.06 Repayments of Provider Advances. (a) Amounts advanced hereunder in respect of a Provider Advance shall be
deposited in the Class A Cash Collateral Account and invested and withdrawn from the Class A Cash Collateral Account as set forth in Sections 3.05(c), 3.05(d), 3.05(e) and 3.05(f) of the Intercreditor Agreement. Subject to Sections 2.07
and 2.09, the Borrower agrees to pay to the Liquidity Provider, on each Regular Distribution Date, commencing on the first Regular Distribution Date after the making of a Provider Advance, interest on the principal amount of any such Provider
Advance, in the amounts determined as provided in Section 3.07; provided, however, that amounts in respect of a Provider Advance withdrawn from the Class A Cash Collateral Account for the purpose of paying interest on the
Class A Certificates in accordance with Section 3.05(f) of the Intercreditor Agreement (the amount of any such withdrawal being (y), in the case of a Downgrade Advance, an “Applied Downgrade Advance” and
(z) in the case of a Non-Extension Advance, an “Applied Non-Extension Advance” and together with an Applied Downgrade Advance, an “Applied Provider Advance”) shall thereafter (subject to
Section 2.06(b)) be treated as an Interest Advance under this Agreement for purposes of determining the Applicable Liquidity Rate for interest payable thereon; provided, further, however, that if, following the making of a
Provider Advance, the Liquidity Provider delivers a Termination Notice to the Borrower pursuant to Section 6.01(a), such Provider Advance shall thereafter be treated as a Final Advance under this Agreement for purposes of determining the
Applicable Liquidity Rate for interest payable thereon. Subject to Sections 2.07 and 2.09, immediately upon the withdrawal of any amounts from the Class A Cash Collateral Account on account of a reduction in the Required Amount, the Borrower
shall repay to the Liquidity Provider a portion of the Provider Advances in a principal amount equal to such reduction, plus interest on the principal amount so repaid as provided in Section 3.07. 

(b) At any time when an Applied Provider Advance or Applied Special Termination Advance (or any portion thereof) is outstanding, upon the
deposit in the Class A Cash Collateral Account of any amount pursuant to clause “fourth” of Section 3.02 of the Intercreditor Agreement (any such amount being a “Replenishment Amount”) for the purpose of
replenishing or increasing the balance thereof up to the Required Amount at such time, (i) the aggregate outstanding principal amount of all Applied Provider Advances and Applied Special Termination Advances (and of Provider Advances and
Special Termination Advances treated as Interest Advances for purposes of determining the Applicable Liquidity Rate for interest payable thereon) shall be automatically reduced by the amount of such Replenishment Amount, and (ii) the aggregate
outstanding principal amount of all Unapplied Provider Advances shall be automatically increased by the amount of such Replenishment Amount. 

  
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 (c) Upon the provision of a Replacement Liquidity Facility in replacement of this Agreement in
accordance with Section 3.05(e) of the Intercreditor Agreement, as provided in Section 3.05(f) of the Intercreditor Agreement, amounts remaining on deposit in the Class A Cash Collateral Account after giving effect to any Applied
Provider Advance or Applied Special Termination Advance on the date of such replacement shall be reimbursed to the Liquidity Provider, but only to the extent such amounts are necessary to repay in full to the Liquidity Provider all amounts owing to
it hereunder. 
 (d) If, at any time after making a Downgrade Advance, the Liquidity Provider satisfies the Threshold Rating and delivers
written notice to that effect to the Borrower and Spirit, as of the second Business Day following receipt of such notice, (i) this Liquidity Facility shall cease to be a Downgraded Facility, (ii) any Unapplied Downgrade Advance shall be
withdrawn from the Class A Cash Collateral Account and reimbursed to the Liquidity Provider, (iii) any Applied Downgrade Advance shall be converted to an Interest Advance, (iv) the Maximum Available Commitment shall be reinstated by
an amount equal to the amount of such Unapplied Downgrade Advance so reimbursed, but not to exceed the Maximum Commitment, and the obligation of the Liquidity Provider to make Advances shall be reinstated in an equal amount and (v) the proviso
in the definition of Maximum Available Commitment shall no longer apply to such Downgrade Advance. 
 Section 2.07 Payments to the
Liquidity Provider Under the Intercreditor Agreement. In order to provide for payment or repayment to the Liquidity Provider of any amounts hereunder, the Intercreditor Agreement provides that amounts available and referred to in Articles II and
III of the Intercreditor Agreement, to the extent payable to the Liquidity Provider pursuant to the terms of the Intercreditor Agreement (including, without limitation, Section 3.05(f) of the Intercreditor Agreement), shall be paid to the
Liquidity Provider in accordance with the terms thereof (but, for the avoidance of doubt, without duplication of or increase in any amounts payable hereunder). Amounts so paid to the Liquidity Provider shall be applied by the Liquidity Provider in
the order of priority required by the applicable provisions of Articles II and III of the Intercreditor Agreement and shall discharge in full the corresponding obligations of the Borrower hereunder. 

Section 2.08 Book Entries. The Liquidity Provider shall maintain in accordance with its usual practice an account or accounts
evidencing the indebtedness of the Borrower resulting from Advances made from time to time and the amounts of principal and interest payable hereunder and paid from time to time in respect thereof; provided, however, that the failure
by the Liquidity Provider to maintain such account or accounts shall not affect the obligations of the Borrower in respect of Advances. 

Section 2.09 Payments from Available Funds Only. All payments to be made by the Borrower under this Agreement shall be made only
from the amounts that constitute Scheduled Payments, Special Payments and other payments under the Operative Agreements, including 

  
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payment under Section 4.02 of the Participation Agreements and payments under Section 2.14 of the Indentures, and only to the extent that the Borrower shall have sufficient income or
proceeds therefrom to enable the Borrower to make payments in accordance with the terms hereof after giving effect to the priority of payments provisions set forth in the Intercreditor Agreement. The Liquidity Provider agrees that it will look
solely to such amounts to the extent available for distribution to it as provided in the Intercreditor Agreement and this Agreement and that the Borrower, in its individual capacity, is not personally liable to it for any amounts payable or
liability under this Agreement except as expressly provided in this Agreement, the Intercreditor Agreement or any Participation Agreement. Amounts on deposit in the Class A Cash Collateral Account shall be available to the Borrower to make
payments under this Agreement only to the extent and for the purposes expressly contemplated in Section 3.05(f) of the Intercreditor Agreement. 

Section 2.10 Extension of the Expiry Date; Non-Extension Advance. If the Liquidity Provider notifies the Borrower and Spirit in
writing before the 25th day prior to any anniversary date of the Closing Date that occurs prior to the 15th day after the Final Legal
Distribution Date for the Class A Certificates (such notice, a “Non-Extension Notice”; and such 25th day, the “Notice Date”) that its
obligations to make Advances hereunder shall not be extended beyond the immediately following anniversary date of the Closing Date (and if the Liquidity Provider shall not have been replaced in accordance with Section 3.05(e) of the
Intercreditor Agreement), the Borrower shall be entitled on and after the Notice Date (but prior to such anniversary date and in any event prior to the then applicable Expiry Date) to request a Non-Extension Advance in accordance with
Section 2.02(b)(i) hereof and Section 3.05(d) of the Intercreditor Agreement. 
 ARTICLE III 

OBLIGATIONS OF THE BORROWER 

Section 3.01 Increased Costs. Without duplication of any rights created by Section 3.03, if as a result of any Regulatory
Change there shall be any increase by an amount reasonably deemed by the Liquidity Provider to be material in the actual cost to the Liquidity Provider of making, funding or maintaining any Advances or its obligation to make any such Advances or
there shall be any reduction by an amount reasonably deemed by the Liquidity Provider to be material in the amount receivable by the Liquidity Provider under this Agreement or the Intercreditor Agreement in respect thereof, and in case of either
such an increase or reduction, such event does not arise from the gross negligence or willful misconduct of the Liquidity Provider, from its breach of any of its representations, warranties, covenants or agreements contained herein or in the
Intercreditor Agreement or from its failure to comply with any such Regulatory Change (any such increase or reduction being referred to herein as an “Increased Cost”), then, subject to Sections 2.07 and 2.09, the Borrower
shall from time to time pay to the Liquidity Provider an amount equal to such Increased Cost within 10 Business Days after delivery to the Borrower and Spirit of a certificate of an officer of the Liquidity Provider describing in reasonable detail
the event by reason of which it claims such Increased Cost and 

  
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the basis for the determination of the amount of such Increased Cost; provided that the Borrower shall be obligated to pay amounts only with respect to any Increased Costs accruing from
the date 120 days prior to the date of delivery of such certificate. Such certificate, in the absence of manifest error, shall be considered prima facie evidence of the amount of the Increased Costs for purposes of this Agreement; provided
that any determinations and allocations by the Liquidity Provider of the effect of any Regulatory Change on the costs of maintaining the Advances or the obligation to make Advances are made on a reasonable basis. For the avoidance of doubt, the
Liquidity Provider shall not be entitled to assert any claim under this Section 3.01 in respect of or attributable to Excluded Taxes. The Liquidity Provider will notify the Borrower and Spirit as promptly as practicable of any event occurring
after the date of this Agreement that will entitle the Liquidity Provider to compensation under this Section 3.01. The Liquidity Provider agrees to investigate all commercially reasonable alternatives for reducing any Increased Costs and to use
all commercially reasonable efforts to avoid or minimize, to the greatest extent possible, any claim in respect of Increased Costs, including, without limitation, by designating a different Lending Office, if such designation or other action would
avoid the need for, or reduce the amount of, any such claim; provided that the foregoing shall not obligate the Liquidity Provider to take any action that would, in its reasonable judgment, cause the Liquidity Provider to take any action that
is not materially consistent with its internal policies or is otherwise materially disadvantageous to the Liquidity Provider or that would cause the Liquidity Provider to incur any material loss or cost, unless the Borrower or Spirit agrees to
reimburse or indemnify the Liquidity Provider therefor. If no such designation or other action is effected, or, if effected, such notice fails to avoid the need for any claim in respect of Increased Costs, Spirit may arrange for a Replacement
Liquidity Facility in accordance with Section 3.05(e) of the Intercreditor Agreement. 
 Notwithstanding the foregoing provisions, in
no event shall the Borrower be required to make payments under this Section 3.01: (a) in respect of any Regulatory Change proposed by any applicable governmental authority (including any branch of a legislature), central bank or comparable
agency of the United States or the Liquidity Provider’s jurisdiction of organization or in which its Lending Office is located and pending as of the date of this Agreement (it being agreed that the Regulatory Changes contemplated by the
Consultative Documents issued by the Basel Committee on Banking Supervision entitled “Strengthening the resilience of the banking sector” and “International framework for liquidity risk measurement, standards and monitoring,”
each dated December 2009, shall not be considered to have been proposed or pending as of the date of this Agreement); (b) if a claim hereunder in respect of an Increased Cost arises through circumstances peculiar to the Liquidity Provider and
that do not affect similarly organized commercial banking institutions in the same jurisdiction generally that are in compliance with the law, rule, regulation or interpretation giving rise to the Regulatory Change relating to such Increased Cost;
(c) if the Liquidity Provider shall fail to comply with its obligations under this Section 3.01 or (d) if the Liquidity Provider is not also seeking payment for similar increased costs in other similarly situated transactions related
to the airline industry. 
 Section 3.02 Reserved. 

  
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 Section 3.03 Withholding Taxes. (a) All payments made by the Borrower under this
Agreement shall be made without deduction or withholding for or on account of any Taxes, unless such deduction or withholding is required by law. If any Taxes are so required to be withheld or deducted from any amounts payable to the Liquidity
Provider under this Agreement, then, subject to Sections 2.07 and 2.09, the Borrower shall pay to the relevant authorities the full amount so required to be deducted or withheld and, without duplication of any rights created by Section 3.01, if
such Taxes are Covered Taxes, pay to the Liquidity Provider such additional amounts as shall be necessary to ensure that the net amount actually received by the Liquidity Provider (after deduction or withholding of all Covered Taxes) shall be equal
to the full amount that would have been received by the Liquidity Provider had no withholding or deduction of Covered Taxes been required. The Liquidity Provider agrees to use reasonable efforts (consistent with applicable legal and regulatory
restrictions) to change the jurisdiction of its Lending Office if making such change would avoid the need for, or reduce the amount of, any such additional amounts that may thereafter accrue and would not, in the reasonable judgment of the Liquidity
Provider, be otherwise materially disadvantageous to the Liquidity Provider. If the Liquidity Provider receives a refund of, or realizes a net Tax benefit not otherwise available to it as a result of, any Taxes for which additional amounts were paid
by the Borrower pursuant to this Section 3.03, the Liquidity Provider shall pay to the Borrower (for deposit into the Collection Account) the amount of such refund (and any interest thereon) or net benefit. 

The Liquidity Provider will (i) provide (on its behalf and on behalf of any participant holding a Participation pursuant to
Section 7.08) to the Borrower (x) on or prior to the Effective Date two valid completed and executed copies of Internal Revenue Service Form W-9, W-8BEN-E or W-8ECI (whichever is applicable), including thereon a valid U.S. taxpayer
identification number (or, with respect to any such participant, such other form or documentation as may be applicable) covering all amounts receivable by it in connection with the transactions contemplated by the Operative Agreements and
(y) thereafter from time to time such additional forms or documentation as may be necessary to establish an available exemption from withholding of United States Tax on payments hereunder so that such forms or documentation are effective for
all periods during which it is the Liquidity Provider and (ii) provide timely notice to the Borrower if any such form or documentation is or becomes inaccurate. The Liquidity Provider shall deliver to the Borrower such other forms or documents
as may be reasonably requested by the Borrower or required by applicable law to establish that payments hereunder are exempt from or entitled to a reduced rate of Covered Taxes. 

(b) All payments (including, without limitation, Advances) made by the Liquidity Provider under this Agreement shall be made free and clear
of, and without reduction for or on account of, any Taxes. If any Taxes are required to be withheld or deducted from any amounts payable to the Borrower under this Agreement, the Liquidity Provider shall (i) within the time prescribed therefor
by applicable law pay to the appropriate governmental or taxing authority the full amount of any such Taxes (and any additional Taxes in respect of the additional amounts payable under clause (ii) hereof) and make such reports or returns in
connection therewith at the time or times and in the manner prescribed by applicable law, and (ii) pay to the Borrower an additional amount which (after deduction of all such Taxes) will be sufficient to

  
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yield to the Borrower the full amount which would have been received by it had no such withholding or deduction been made. Within 30 days after the date of each payment hereunder, the Liquidity
Provider shall furnish to the Borrower the original or a certified copy of (or other documentary evidence of) the payment of the Taxes applicable to such payment. 

If any exemption from, or reduction in the rate of, any Taxes required to be borne by the Liquidity Provider under this Section 3.03(b)
is reasonably available to the Borrower without providing any information regarding the holders or beneficial owners of the Certificates, the Borrower shall deliver the Liquidity Provider such form or forms and such other evidence of the eligibility
of the Borrower for such exemption or reductions (but without any requirement to provide any information regarding the holders or beneficial owners of the Certificates) as the Liquidity Provider may reasonably identify to the Borrower as being
required as a condition to exemption from, or reduction in the rate of, such Taxes. 
 (c) If a payment made hereunder to the Liquidity
Provider would be subject to U.S. federal withholding Tax imposed by FATCA if the Liquidity Provider were to fail to comply with the applicable reporting requirement of FATCA (including without limitation those contained in Section 1471(b) or
1472(b) of the Code, as applicable), the Liquidity Provider shall deliver to the Borrower at the time or times prescribed by law and at such time or times reasonably requested by the Borrower such documentation prescribed by applicable law
(including as prescribed by Section 1471(b)(3)(C)(i) of the Code) and such additional documentation reasonably requested by the Borrower as may be necessary for the Borrower to comply with the Borrower’s obligations under FATCA and to
determine whether the Liquidity Provider has complied with the Liquidity Provider’s obligations under FATCA or to determine the amount to deduct and withhold from such payment. Solely for purposes of this paragraph, “FATCA” shall
include any amendments made to FATCA after the date of this Agreement. 
 Section 3.04 Payments. Subject to Sections 2.07 and
2.09, the Borrower shall make or cause to be made each payment to the Liquidity Provider under this Agreement so as to cause the same to be received by the Liquidity Provider not later than 1:00 p.m. (New York City time) on the day when due.
The Borrower shall make all such payments in Dollars, to the Liquidity Provider in immediately available funds, by wire transfer to the account of Natixis, acting via its New York Branch, at JPMorgan Chase Bank, ABA No. 021000021, For Account
of Natixis, NY Branch, Account #: 544 775330, Reference to: Spirit 2015-1A EETC, Attention: Loan Services Unit; or to such other U.S. bank account as the Liquidity Provider may from time to time direct the Subordination Agent. 

Section 3.05 Computations. All computations of interest based on the Base Rate shall be made on the basis of a year of 365 or 366
days, as the case may be, and all computations of interest based on the LIBOR Rate shall be made on the basis of a year of 360 days, in each case for the actual number of days (including the first day but excluding the last day) occurring in the
period for which such interest is payable. 

  
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 Section 3.06 Payment on Non-Business Days.
Whenever any payment to be made hereunder shall be stated to be due on a day other than a Business Day, such payment shall be made on the next succeeding Business Day and no additional interest shall be due as a result (and if so made, shall be
deemed to have been made when due). If any payment in respect of interest on an Advance is so deferred to the next succeeding Business Day, such deferral shall not delay the commencement of the next Interest Period for such Advance (if such Advance
is a LIBOR Advance) or reduce the number of days for which interest will be payable on such Advance on the next Interest Payment Date for such Advance. 

Section 3.07 Interest. (a) Subject to Sections 2.07 and 2.09, the Borrower shall pay, or shall cause to be paid, without
duplication, interest on (i) the unpaid principal amount of each Advance from and including the date of such Advance (or, in the case of an Applied Provider Advance or Applied Special Termination Advance, from and including the date on which
the amount thereof was withdrawn from the Class A Cash Collateral Account to pay interest on the Class A Certificates) to but excluding the date such principal amount shall be paid in full (or, in the case of an Applied Provider Advance or
Applied Special Termination Advance, the date on which the Class A Cash Collateral Account is fully replenished in respect of such Advance) and (ii), to the extent permitted by law, any other amount due hereunder (whether fees,
commissions, expenses or other amounts or installments of interest on Advances or any such other amount) that is not paid when due (whether at stated maturity, by acceleration or otherwise) from and including the due date thereof to but excluding
the date such amount is paid in full, in each such case, at the interest rate per annum for each day that such amount remains overdue and unpaid equal to the Applicable Liquidity Rate for such Advance or such other amount, as the case may be, as in
effect for such day, but in no event in any case referred to in clause (i) or (ii) above at a rate per annum greater than the maximum rate permitted by applicable law; provided, however, that, if at any time the otherwise
applicable interest rate as set forth in this Section 3.07 shall exceed the maximum rate permitted by applicable law, then to the maximum extent permitted by applicable law any subsequent reduction in such interest rate will not reduce the rate
of interest payable pursuant to this Section 3.07 below the maximum rate permitted by applicable law until the total amount of interest accrued equals the absolute amount of interest that would have accrued (without additional interest thereon)
if such otherwise applicable interest rate as set forth in this Section 3.07 had at all relevant times been in effect. 
 (b) Except as
provided in Section 3.07(e), each Advance will be either a Base Rate Advance or a LIBOR Advance as provided in this Section 3.07. Each such Advance will be a Base Rate Advance for the period from the date of its Borrowing to (but
excluding) the third Business Day following the Liquidity Provider’s receipt of the Notice of Borrowing for such Advance. Thereafter, such Advance shall be a LIBOR Advance; provided that a Provider Advance shall always be a LIBOR Advance
unless the Borrower elects otherwise. 
 (c) Each LIBOR Advance shall bear interest during each Interest Period at a rate per annum equal to
the LIBOR Rate for such Interest Period plus the Applicable Margin for such LIBOR Advance, payable in arrears on the last day of such Interest Period and, in the event of the payment of principal of such LIBOR Advance on a day other than such last
day, on the date of such payment (to the extent of interest accrued on the amount of principal repaid). 

  
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 (d) Each Base Rate Advance shall bear interest at a rate per annum equal to the Base Rate plus
the Applicable Margin for such Base Rate Advance, payable in arrears on each Regular Distribution Date and, in the event of the payment of principal of such Base Rate Advance on a day other than a Regular Distribution Date, on the date of such
payment (to the extent of interest accrued on the amount of principal repaid). 
 (e) Each outstanding Unapplied Non-Extension Advance shall
bear interest in (i) an amount equal to the Investment Earnings on the amounts on deposit in the Class A Cash Collateral Account on account of such Unapplied Non-Extension Advance plus (ii) an amount equal to interest at the
Applicable Margin on the amount of such Unapplied Non-Extension Advance, from time to time, payable in arrears on each Regular Distribution Date. 

(f) Each amount not paid when due hereunder (whether fees, commissions, expenses or other amounts or installments of interest on Advances but
excluding Advances) shall bear interest, to the extent permitted by applicable law, at a rate per annum equal to the Base Rate plus 2.0% per annum until paid. 

(g) If at any time, the Liquidity Provider shall have determined (which determination shall be conclusive and binding upon the
Borrower, absent manifest error) that, by reason of circumstances affecting the relevant interbank lending market generally, the LIBOR Rate determined or to be determined for the next succeeding Interest Period will not adequately and fairly reflect
the cost to the Liquidity Provider (as conclusively certified by the Liquidity Provider, absent manifest error) of making or maintaining Advances, the Liquidity Provider shall give facsimile or telephonic notice thereof (a “Rate
Determination Notice”) to the Borrower and Spirit. If such notice is given, then the outstanding principal amount of the LIBOR Advances shall be converted to Base Rate Advances effective from the date of the Rate Determination Notice;
provided that the Applicable Liquidity Rate in respect of such Base Rate Advances shall be increased by one percent (1.00%). The Liquidity Provider shall withdraw a Rate Determination Notice given hereunder when the Liquidity Provider
determines that the circumstances giving rise to such Rate Determination Notice no longer apply to the Liquidity Provider, and the Base Rate Advances shall be converted to LIBOR Advances effective as of the first day of the next succeeding Interest
Period after the date of such withdrawal.  
 (h) Each change in the Base Rate shall become effective
immediately. The rates of interest specified in this Section 3.07 with respect to any Advance or other amount shall be referred to as the “Applicable Liquidity Rate”. 

  
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 Section 3.08 Replacement of Borrower. Subject to Section 5.02, from time to time
and subject to the successor Borrower’s meeting the eligibility requirements set forth in Section 6.09 of the Intercreditor Agreement applicable to the Subordination Agent, upon the effective date and time specified in a written and
completed Notice of Replacement Subordination Agent in substantially the form of Annex VIII (a “Notice of Replacement Subordination Agent”) delivered to the Liquidity Provider by the then Borrower, the successor
Borrower designated therein shall become the Borrower for all purposes hereunder. 
 Section 3.09 Funding Loss Indemnification.
The Borrower shall pay to the Liquidity Provider, upon the request of the Liquidity Provider, such amount or amounts as shall be sufficient (in the reasonable opinion of the Liquidity Provider) to compensate it for any loss, cost or expense incurred
by reason of the liquidation or redeployment of deposits or other funds acquired by the Liquidity Provider to fund or maintain any LIBOR Advance (but excluding loss of the Applicable Margin or anticipated profits) incurred as a result of: 

(1) Any repayment of a LIBOR Advance on a date other than the last day of the Interest Period for such Advance; or 

(2) Any failure by the Borrower to borrow a LIBOR Advance on the date for borrowing specified in the relevant notice under
Section 2.02. 
 Section 3.10 Illegality. Notwithstanding any other provision in this Agreement, if any change in any law,
rule or regulation applicable to or binding on the Liquidity Provider, or any change in the interpretation or administration thereof by any governmental authority, central bank or comparable agency charged with the interpretation or administration
thereof, or compliance by the Liquidity Provider with any request or directive (whether or not having the force of law) of any such authority, central bank or comparable agency shall make it unlawful or impossible for the Liquidity Provider to
maintain or fund its LIBOR Advances, then upon notice to the Borrower and Spirit by the Liquidity Provider, the outstanding principal amount of the LIBOR Advances shall be converted to Base Rate Advances (a) immediately upon demand of the
Liquidity Provider, if such change or compliance with such request, in the reasonable judgment of the Liquidity Provider, requires immediate conversion; or (b) at the expiration of the last Interest Period to expire before the effective date of
any such change or request. The Liquidity Provider will notify the Borrower and Spirit as promptly as practicable of any event that will or to its knowledge is reasonably likely to lead to the conversion of LIBOR Advances to Base Rate Advances under
this Section 3.10; provided that a failure by the Liquidity Provider to notify the Borrower or Spirit of an event that is reasonably likely to lead to such a conversion prior to the time that it is determined that such event will lead to
such a conversion shall not prejudice the rights of the Liquidity Provider under this Section 3.10. The Liquidity Provider agrees to investigate all commercially reasonable alternatives for avoiding the need for such conversion, including,
without limitation, designating a different Lending Office, if such designation or other action would avoid the need to convert such LIBOR Advances to Base Rate 

  
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Advances; provided that the foregoing shall not obligate the Liquidity Provider to take any action that would, in its reasonable judgment, cause the Liquidity Provider to incur any
material loss or cost, unless the Borrower or Spirit agrees to reimburse or indemnify the Liquidity Provider therefor. If no such designation or other action is effected, or, if effected, fails to avoid the need for conversion of the LIBOR Advances
to Base Rate Advances, Spirit may arrange for a Replacement Liquidity Facility in accordance with Section 3.05(e) of the Intercreditor Agreement. 

ARTICLE IV 
 CONDITIONS PRECEDENT

 Section 4.01 Conditions Precedent to Effectiveness of Section 2.01. Section 2.01 of this Agreement shall become
effective on and as of the first date (the “Effective Date”) on which the following conditions precedent have been satisfied (or waived by the appropriate party or parties): 

(a) The Liquidity Provider shall have received on or before the Closing Date each of the following, and in the case of each document delivered
pursuant to paragraphs (i), (ii) and (iii), each in form and substance satisfactory to the Liquidity Provider: 

(i) This Agreement and the Fee Letter duly executed on behalf of the Borrower and, in the case of the Fee Letter, Spirit; 

(ii) The Intercreditor Agreement duly executed on behalf of each of the parties thereto (other than the Liquidity Provider);

 (iii) Fully executed copies of each of the Operative Agreements executed and delivered on or before the Closing Date
(other than this Agreement, the Fee Letter and the Intercreditor Agreement); 
 (iv) A copy of the Prospectus Supplement and
specimen copies of the Class A Certificates; 
 (v) An executed copy of each opinion (other than the negative assurance
letter of Debevoise and Plimpton LLP, special counsel to Spirit, and the opinion and the negative assurance letter of White & Case LLP, special counsel to the Underwriters) delivered on the Closing Date pursuant to the Underwriting
Agreement (in the case of each such opinion, either addressed to the Liquidity Provider or accompanied 

  
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by a letter from the counsel rendering such opinion to the effect that the Liquidity Provider is entitled to rely on such opinion as of its date as if it were addressed to the Liquidity
Provider); 
 (vi) An executed copy of each document, instrument, certificate and opinion delivered on or before the Closing
Date pursuant to the Class A Trust Agreement, the Intercreditor Agreement and the other Operative Agreements (in the case of each such opinion, either addressed to the Liquidity Provider or accompanied by a letter from the counsel rendering
such opinion to the effect that the Liquidity Provider is entitled to rely on such opinion as of its date as if it were addressed to the Liquidity Provider); and 

(vii) An agreement from Spirit, pursuant to which (x) Spirit agrees to provide copies of quarterly financial statements
and audited annual financial statements to the Liquidity Provider (which Spirit may provide in an electronic format by electronic mail or making such available over the internet) and (y) Spirit agrees to allow the Liquidity Provider to discuss
the transactions contemplated by the Operative Agreements with officers and employees of Spirit. 
 (b) On and as of the Effective Date no
event shall have occurred and be continuing, or would result from the entering into of this Agreement or the making of any Advance, which constitutes a Liquidity Event of Default. 

(c) The Liquidity Provider shall have received payment in full of the fees and other sums required to be paid to or for the account of the
Liquidity Provider on or prior to the Effective Date pursuant to the Fee Letter. 
 (d) All conditions precedent to the issuance of the
Certificates under the Trust Agreements shall have been satisfied or waived, all conditions precedent to the effectiveness of the other Liquidity Facilities shall have been satisfied or waived, and all conditions precedent to the purchase of the
Class A Certificates and the Class B Certificates by the Underwriters under the Underwriting Agreement shall have been satisfied (unless any of such conditions precedent under the Underwriting Agreement shall have been waived by the
Underwriters). 
 (e) The Borrower and Spirit shall have received a certificate, dated the Effective Date signed by a duly authorized
representative of the Liquidity Provider, certifying that all conditions precedent specified in this Section 4.01 have been satisfied or waived by the Liquidity Provider. 

Section 4.02 Conditions Precedent to Borrowing. The obligation of the Liquidity Provider to make an Advance on the occasion of
each Borrowing shall be subject to the 

  
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conditions precedent that the Effective Date shall have occurred and, prior to the time of such Borrowing, the Borrower shall have delivered a Notice of Borrowing which conforms to the terms and
conditions of this Agreement. 
 ARTICLE V 

COVENANTS 
 Section 5.01
Affirmative Covenants of the Borrower. So long as any Advance shall remain unpaid or the Liquidity Provider shall have any Maximum Available Commitment hereunder or the Borrower shall have any obligation to pay any amount to the Liquidity
Provider hereunder, the Borrower will, unless the Liquidity Provider shall otherwise consent in writing: 
 (a) Performance of
Agreements. Subject to Sections 2.07 and 2.09, punctually pay or cause to be paid all amounts payable by it under this Agreement and the Intercreditor Agreement and observe and perform in all material respects the conditions, covenants and
requirements applicable to it contained in this Agreement and the Intercreditor Agreement; 
 (b) Reporting Requirements. Furnish to
the Liquidity Provider with reasonable promptness, such other information and data with respect to the transactions contemplated by the Operative Agreements as from time to time may be reasonably requested by the Liquidity Provider; and permit the
Liquidity Provider, upon reasonable notice, to inspect the Borrower’s books and records with respect to such transactions and to meet with officers and employees of the Borrower to discuss such transactions; and 

(c) Certain Operative Agreements. Furnish to the Liquidity Provider, with reasonable promptness, copies of such Operative Agreements
entered into after the date hereof as from time to time may be reasonably requested by the Liquidity Provider. 
 Section 5.02
Negative Covenants of the Borrower. Subject to the first and fourth paragraphs of Section 7.01(a) of the Intercreditor Agreement and Section 7.01(b) of the Intercreditor Agreement, so long as any Advance shall remain unpaid or the
Liquidity Provider shall have any Maximum Available Commitment hereunder or the Borrower shall have any obligation to pay any amount to the Liquidity Provider hereunder, the Borrower will not appoint or permit or suffer to be appointed any successor
Borrower without the prior written consent of the Liquidity Provider, which consent shall not be unreasonably withheld or delayed. 

  
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 ARTICLE VI 

LIQUIDITY EVENTS OF DEFAULT AND SPECIAL TERMINATION 

Section 6.01 Liquidity Events of Default. (a) If any Liquidity Event of Default has occurred and is continuing and there is a
Performing Note Deficiency, the Liquidity Provider may, in its discretion, deliver to the Borrower and Spirit a Termination Notice, the effect of which shall be to cause (i) the Termination Date to occur on the fifth Business Day after the date
on which such Termination Notice is received by the Borrower and Spirit, (ii) the Borrower to promptly request, and the Liquidity Provider to promptly make, a Final Advance in accordance with Section 2.02(c) hereof and Section 3.05(i)
of the Intercreditor Agreement, (iii) all other outstanding Advances to be automatically converted into Final Advances for purposes of determining the Applicable Liquidity Rate for interest payable thereon and (iv) subject to Sections 2.07
and 2.09, all Advances, any accrued interest thereon and any other amounts outstanding hereunder to become immediately due and payable to the Liquidity Provider. 

(b) If the aggregate Pool Balance of the Class A Certificates is greater than the aggregate outstanding principal amount of the Series A
Equipment Notes (other than any Series A Equipment Notes previously sold by the Borrower or with respect to which the Aircraft related to such Series A Equipment Notes has been disposed of by the Loan Trustee) at any time during the 18-month period
ending on April 1, 2028, the Liquidity Provider may, in its discretion, deliver to the Borrower and Spirit a Special Termination Notice, the effect of which shall be to cause (i) the Termination Date to occur on the fifth Business Day
after the date on which such Special Termination Notice is received by the Borrower and Spirit, (ii) the Borrower to promptly request, and the Liquidity Provider to promptly make, a Special Termination Advance in accordance with
Section 2.02(d) hereof and Section 3.05(k) of the Intercreditor Agreement, and (iii) subject to Sections 2.07 and 2.09, all Advances (including, without limitation, any Unapplied Provider Advance), to be automatically treated as
Special Termination Advances. 
 ARTICLE VII 

MISCELLANEOUS 
 Section 7.01
No Oral Modifications or Continuing Waivers. No terms or provisions of this Agreement may be changed, waived, discharged or terminated orally, but only by an instrument in writing signed by the Borrower and the Liquidity Provider and any
other Person whose consent is required pursuant to this Agreement; provided that no such change or other action shall affect the payment obligations of Spirit or the rights of Spirit without Spirit’s prior written consent; and any waiver
of the terms hereof shall be effective only in the specific instance and for the specific purpose given. 

  
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 Section 7.02 Notices. Unless otherwise expressly specified or permitted by the terms
hereof, all notices, requests, demands, authorizations, directions, consents, waivers or documents required or permitted under the terms and provisions of this Agreement shall be in English and in writing, and given by United States registered or
certified mail, courier service or facsimile, and any such notice shall be effective when delivered (or, if delivered by facsimile, upon completion of transmission and confirmation by the sender (by a telephone call to a representative of the
recipient or by machine confirmation) that such transmission was received) addressed as follows: 
 If to the Borrower, to: 

WILMINGTON TRUST, NATIONAL ASSOCIATION 

1100 North Market Street 

Wilmington, Delaware 19890-1605 

Attention: Corporate Trust Administration 

Ref.: Spirit 2015-1A EETC 

Telephone: (302) 636-6387 

Telecopy: (302) 636-4140 

If to the Liquidity Provider, to: 

NATIXIS, acting via its New York Branch 

Attention: Vinh Nguyen 
 1251
Avenue of the Americas 
 New York, New York 10020-1128 

Telephone: 212-891-5811 

Telecopy: 646-282-2321 
 E-mail:
vinh.nguyen@us.natixis.com 
 and 

NATIXIS, acting via its New York Branch 

Attention: Martha Sealy 
 1251
Avenue of the Americas 
 New York, New York 10020-1128 

Telephone: 212-872-5031 

Telecopy: 347-402-3031 
 E-mail:
martha.sealy@us.natixis.com 
 Cc: aviationfinanceportfolio@us.natixis.com 

Any party, by notice to the other party hereto, may designate additional or different addresses for subsequent notices or communications.
Whenever the words “notice” or “notify” or similar words are used herein, they mean the provision of formal notice as set forth in this Section 7.02. 

  
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 Section 7.03 No Waiver; Remedies. No failure on the part of the Liquidity Provider to
exercise, and no delay in exercising, any right under this Agreement shall operate as a waiver thereof; nor shall any single or partial exercise of any right under this Agreement preclude any other or further exercise thereof or the exercise of any
other right. The remedies herein provided are cumulative and not exclusive of any remedies provided by law. 
 Section 7.04 Further
Assurances. The Borrower agrees to do such further acts and things and to execute and deliver to the Liquidity Provider such additional assignments, agreements, powers and instruments as the Liquidity Provider may reasonably require or deem
advisable to carry into effect the purposes of this Agreement and the other Operative Agreements or to better assure and confirm unto the Liquidity Provider its rights, powers and remedies hereunder and under the other Operative Agreements. 

Section 7.05 Indemnification; Survival of Certain Provisions. The Liquidity Provider shall be indemnified hereunder to the extent
and in the manner described in Section 4.02 of the Participation Agreements. In addition, the Borrower agrees to indemnify, protect, defend and hold harmless each Liquidity Indemnitee from and against all Expenses of any kind or nature
whatsoever (other than any Expenses of the nature described in Sections 3.01, 3.03, 3.09 or 7.07 or in the Fee Letter (regardless of whether indemnified against pursuant to said Sections or in such Fee Letter)), that may be imposed on or incurred by
such Liquidity Indemnitee, in any way relating to, resulting from, or arising out of or in connection with, any action, suit or proceeding by any third party against such Liquidity Indemnitee and relating to this Agreement, the Fee Letter, the
Intercreditor Agreement or any Participation Agreement; provided, however, that the Borrower shall not be required to indemnify, protect, defend and hold harmless any Liquidity Indemnitee in respect of any Expense of such Liquidity
Indemnitee to the extent such Expense is (i) attributable to the gross negligence or willful misconduct of such Liquidity Indemnitee or any other Liquidity Indemnitee, (ii) an ordinary and usual operating overhead expense,
(iii) attributable to the failure by such Liquidity Indemnitee or any other Liquidity Indemnitee to perform or observe any agreement, covenant or condition on its part to be performed or observed in this Agreement, the Intercreditor Agreement,
the Fee Letter or any other Operative Agreement to which it is a party or (iv) otherwise excluded from the indemnification provisions contained in Section 4.02 of the Participation Agreements. The provisions of Sections 3.01, 3.03, 3.09,
7.05 and 7.07 and the indemnities contained in Section 4.02 of the Participation Agreements shall survive the termination of this Agreement. 

Section 7.06 Liability of the Liquidity Provider. (a) Neither the Liquidity Provider nor any of its officers, employees or
directors shall be liable or responsible for: (i) the use which may be made of the Advances or any acts or omissions of the Borrower or any beneficiary or transferee in connection therewith; (ii) the validity, sufficiency or genuineness of
documents, or of any endorsement thereon, even if such documents should prove to be in any or all respects invalid, insufficient, fraudulent or forged; or (iii) the making of Advances by the Liquidity Provider against delivery of a Notice of
Borrowing and other documents which do not comply with the terms hereof; provided, however, that the Borrower shall have a claim against the 

  
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Liquidity Provider, and the Liquidity Provider shall be liable to the Borrower, to the extent of any damages suffered by the Borrower that were the result of (A) the Liquidity
Provider’s willful misconduct or gross negligence in determining whether documents presented hereunder comply with the terms hereof or (B) any breach by the Liquidity Provider of any of the terms of this Agreement or the Intercreditor
Agreement, including, but not limited to, the Liquidity Provider’s failure to make lawful payment hereunder after the delivery to it by the Borrower of a Notice of Borrowing complying with the terms and conditions hereof. 

(b) Neither the Liquidity Provider nor any of its officers, employees or directors or affiliates shall be liable or responsible in any respect
for (i) any error, omission, interruption or delay in transmission, dispatch or delivery of any message or advice, however transmitted, in connection with this Agreement or any Notice of Borrowing delivered hereunder or (ii) any action,
inaction or omission which may be taken by it in good faith, absent willful misconduct or negligence (in which event the extent of the Liquidity Provider’s potential liability to the Borrower shall be limited as set forth in the immediately
preceding paragraph), in connection with this Agreement or any Notice of Borrowing. 
 Section 7.07 Certain Costs and Expenses.
The Borrower agrees promptly to pay, or cause to be paid, (a) the reasonable fees, expenses and disbursements of Winston & Strawn LLP, special counsel for the Liquidity Provider, in connection with the preparation, negotiation,
execution, delivery, filing and recording of the Operative Agreements, any waiver or consent thereunder or any amendment thereof and (b) if a Liquidity Event of Default occurs, all
out-of-pocket expenses incurred by the Liquidity Provider, including reasonable fees and disbursements of counsel, in connection with such Liquidity Event of Default and
any collection, bankruptcy, insolvency and other enforcement proceedings in connection therewith. In addition, the Borrower shall pay any and all recording, stamp and other similar taxes and fees payable or determined to be payable in the United
States in connection with the execution, delivery, filing and recording of this Agreement, any other Operative Agreement and such other documents, and agrees to save the Liquidity Provider harmless from and against any and all liabilities with
respect to or resulting from any delay in paying or omission to pay such taxes or fees. 
 Section 7.08 Binding Effect;
Participations. (a) This Agreement shall be binding upon and inure to the benefit of the Borrower and the Liquidity Provider and their respective successors and permitted assigns, except that neither the Liquidity Provider (except as
otherwise provided in this Section 7.08) nor (except as contemplated by Section 3.08) the Borrower shall have the right to assign, pledge or otherwise transfer its rights or obligations hereunder or any interest herein, subject to the
Liquidity Provider’s right to grant Participations pursuant to Section 7.08(b). 
 (b) The Liquidity Provider agrees that it will
not grant any participation (including, without limitation, a “risk participation”) (any such participation, a “Participation”) in or to all or a portion of its rights and obligations hereunder or
under the other Operative 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 30 

 
Agreements, unless all of the following conditions are satisfied: (i) such Participation is to a Permitted Transferee, (ii) such Participation is made in accordance with all applicable
laws, including, without limitation, the Securities Act of 1933, as amended, the Trust Indenture Act of 1939, as amended, any laws or regulations imposing U.S. economic sanctions measures or any orders or licenses issued thereunder and any other
applicable laws relating to the transfer of similar interests and (iii) such Participation shall not be made under circumstances that require registration under the Securities Act of 1933, as amended, or qualification of any indenture under the
Trust Indenture Act of 1939, as amended. Notwithstanding any such Participation, the Liquidity Provider agrees that (1) the Liquidity Provider’s obligations under the Operative Agreements shall remain unchanged, and such participant shall
have no rights or benefits as against Spirit or the Borrower or under any Operative Agreement, (2) the Liquidity Provider shall remain solely responsible to the other parties to the Operative Agreements for the performance of such obligations,
(3) the Liquidity Provider shall remain the maker of any Advances, and the other parties to the Operative Agreements shall continue to deal solely and directly with the Liquidity Provider in connection with the Advances and the Liquidity
Provider’s rights and obligations under the Operative Agreements, (4) the Liquidity Provider shall be solely responsible for any withholding Taxes or any filing or reporting requirements relating to such Participation and shall hold the
Borrower and Spirit and their respective successors, permitted assigns, affiliates, agents and servants harmless against the same and (5) neither Spirit nor the Borrower shall be required to pay to the Liquidity Provider any amount under
Section 3.01 or Section 3.03 greater than it would have been required to pay had there not been any grant of a Participation by the Liquidity Provider. The Liquidity Provider may, in connection with any Participation or proposed
Participation pursuant to this Section 7.08(b), disclose to the participant or proposed participant any information relating to the Operative Agreements or to the parties thereto furnished to the Liquidity Provider thereunder or in connection
therewith and permitted to be disclosed by the Liquidity Provider; provided, however, that prior to any such disclosure, the participant or proposed participant shall agree in writing for the express benefit of the Borrower and Spirit
to preserve the confidentiality of any confidential information included therein (subject to customary exceptions). 
 (c) Notwithstanding
the other provisions of this Section 7.08, the Liquidity Provider may assign and pledge all or any portion of the Advances owing to it to any Federal Reserve Bank or the United States Treasury as collateral security pursuant to Regulation A of
the Board of Governors of the Federal Reserve System and any Operating Circular issued by such Federal Reserve Bank; provided that any payment in respect of such assigned Advances made by the Borrower to the Liquidity Provider in accordance
with the terms of this Agreement shall satisfy the Borrower’s obligations hereunder in respect of such assigned Advance to the extent of such payment. No such assignment shall release the Liquidity Provider from its obligations hereunder. 

Section 7.09 Severability. To the extent permitted by applicable law, any provision of this Agreement which is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 31 

 Section 7.10 Governing Law. THIS AGREEMENT HAS BEEN DELIVERED IN THE STATE OF NEW
YORK AND THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK, INCLUDING ALL MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE. 

Section 7.11 Submission to Jurisdiction; Waiver of Jury Trial; Waiver of Immunity. (a) Each of the parties hereto, to the
extent it may do so under applicable law, for purposes hereof hereby (i) irrevocably submits itself to the non-exclusive jurisdiction of the courts of the State of New York sitting in the City of New York
and to the non-exclusive jurisdiction of the United States District Court for the Southern District of New York, for the purposes of any suit, action or other proceeding arising out of this Agreement, the
subject matter hereof or any of the transactions contemplated hereby brought by any party or parties hereto or thereto, or their successors or permitted assigns and (ii) waives, and agrees not to assert, by way of motion, as a defense, or
otherwise, in any such suit, action or proceeding, that the suit, action or proceeding is brought in an inconvenient forum, that the venue of the suit, action or proceeding is improper or that this Agreement or the subject matter hereof or any of
the transactions contemplated hereby may not be enforced in or by such courts. 
 (b) THE BORROWER AND THE LIQUIDITY PROVIDER EACH HEREBY
AGREE TO WAIVE THEIR RESPECTIVE RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THIS AGREEMENT OR ANY DEALINGS BETWEEN THEM RELATING TO THE SUBJECT MATTER OF THIS AGREEMENT AND THE RELATIONSHIP THAT IS BEING
ESTABLISHED, including, without limitation, contract claims, tort claims, breach of duty claims and all other common law and statutory claims. The Borrower and the Liquidity Provider each warrant and represent that it has reviewed this waiver with
its legal counsel, and that it knowingly and voluntarily waives its jury trial rights following consultation with such legal counsel. TO THE EXTENT PERMITTED BY APPLICABLE LAW, THIS WAIVER IS IRREVOCABLE, AND CANNOT BE MODIFIED EITHER ORALLY OR IN
WRITING, AND THIS WAIVER SHALL APPLY TO ANY SUBSEQUENT AMENDMENTS, RENEWALS, SUPPLEMENTS OR MODIFICATIONS TO THIS AGREEMENT. 
 (c) To the
extent that the Liquidity Provider or any of its properties has or may hereafter acquire any right of immunity, whether characterized as sovereign immunity or otherwise, and whether under the United States Foreign Sovereign Immunities Act of 1976
(or any successor legislation) or otherwise, from any legal proceedings, whether in the United States or elsewhere, to enforce or collect upon this Agreement, including, without limitation, immunity from suit or service of process, immunity from
jurisdiction or judgment of any court or tribunal or execution of a judgment, or immunity of any of its property from attachment prior to any entry 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 32 

 
of judgment, or from attachment in aid of execution upon a judgment, the Liquidity Provider hereby irrevocably and expressly waives any such immunity, and agrees not to assert any such right or
claim in any such proceeding, whether in the United States or elsewhere. 
 Section 7.12 Counterparts. This Agreement may be
executed in any number of counterparts (and each party shall not be required to execute the same counterpart). Each counterpart of this Agreement including a signature page or pages executed by each of the parties hereto shall be an original
counterpart of this Agreement, but all of such counterparts together shall constitute one instrument. 
 Section 7.13 Entirety.
This Agreement and the Intercreditor Agreement constitute the entire agreement of the parties hereto with respect to the subject matter hereof and supersede all prior understandings and agreements of such parties. 

Section 7.14 Headings. The headings of the various Articles and Sections herein and in the Table of Contents hereto are for
convenience of reference only and shall not define or limit any of the terms or provisions hereof. 
 Section 7.15 Liquidity
Provider’s Obligation to Make Advances. EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, THE OBLIGATIONS OF THE LIQUIDITY PROVIDER TO MAKE ADVANCES HEREUNDER, AND THE BORROWER’S RIGHTS TO DELIVER NOTICES OF BORROWING REQUESTING THE
MAKING OF ADVANCES HEREUNDER, SHALL BE ABSOLUTE, UNCONDITIONAL AND IRREVOCABLE, AND SHALL BE PAID OR PERFORMED, IN EACH CASE STRICTLY IN ACCORDANCE WITH THE TERMS OF THIS AGREEMENT. 

Section 7.16 Head Office Obligations. The Liquidity Provider is Natixis, a French bank, acting through its New York Branch. The
Liquidity Provider hereby agrees that, notwithstanding the place of booking or its jurisdiction of incorporation or organization, the obligations of the Liquidity Provider hereunder are also the obligations of the head office of Natixis in Paris,
France (the “Head Office”). Accordingly, any beneficiary of this Agreement will be able to proceed directly against the Head Office, if the Liquidity Provider defaults in its obligations to such beneficiary under this
Agreement. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 33 

 IN WITNESS WHEREOF, the parties have caused this Agreement to be duly executed and delivered by
their respective officers thereunto duly authorized as of the date first set forth above. 
  

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, not in its individual capacity but solely as Subordination Agent, as agent and trustee for the Class A Trust, as Borrower
		
	By:	 	 /s/ Scott Wetzel

		 	Name: Scott Wetzel
		 	Title: Financial Services Officer
	
	NATIXIS, ACTING VIA ITS NEW YORK BRANCH, as Liquidity Provider
		
	By:	 	 /s/ Vinh Nguyen

		 	Name: Vinh Nguyen
		 	Title: Vice President
		
	By:	 	 /s/ Lily Cheung

		 	Name: Lily Cheung
		 	Title: Vice President

  
 Signature Page 

  
 Revolving Credit Agreement
(Class A) 
 (Spirit 2015-1 EETC) 

 ANNEX I to 

REVOLVING CREDIT AGREEMENT 

FORM OF INTEREST ADVANCE NOTICE OF BORROWING 

INTEREST ADVANCE NOTICE OF BORROWING 

The undersigned, a duly authorized signatory of the undersigned borrower (the “Borrower”), hereby certifies to
NATIXIS, acting via its New York Branch (the “Liquidity Provider”), with reference to the Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between the Borrower and the Liquidity Provider (the
“Liquidity Agreement”; the terms defined therein and not otherwise defined herein being used herein as therein defined or referenced), that: 

(1) The Borrower is the Subordination Agent under the Intercreditor Agreement. 

(2) The Borrower is delivering this Notice of Borrowing for the making of an Interest Advance by the Liquidity Provider to be
used for the payment of the interest on the Class A Certificates which is payable on             ,         (the “Distribution
Date”) in accordance with the terms and provisions of the Class A Trust Agreement and the Class A Certificates, which Advance is requested to be made on             ,
        . The Interest Advance should be remitted to [insert wire and account details]. 

(3) The amount of the Interest Advance requested hereby (i) is
$            , to be applied in respect of the payment of the interest which is due and payable on the Class A Certificates on the Distribution Date, (ii) does not include any
amount with respect to the payment of principal of, or premium on, the Class A Certificates, or principal of, or interest or premium on the Class B Certificates or any Additional Certificates, if issued, (iii) was computed in
accordance with the provisions of the Class A Certificates, the Class A Trust Agreement and the Intercreditor Agreement (a copy of which computation is attached hereto as Schedule I), (iv) does not exceed the Maximum Available
Commitment on the date hereof and (v) has not been and is not the subject of a prior or contemporaneous Notice of Borrowing. 

(4) Upon receipt by or on behalf of the Borrower of the amount requested hereby, (a) the Borrower will apply the same in
accordance with the terms of Section 3.05(b) of the Intercreditor Agreement, (b) no portion of such amount shall be applied by the Borrower for any other purpose and (c) no portion of such amount until so applied shall be commingled
with other funds held by the Borrower. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 The Borrower hereby acknowledges that, pursuant to the Liquidity Agreement, the making of the
Interest Advance as requested by this Notice of Borrowing shall automatically reduce, subject to reinstatement in accordance with the terms of the Liquidity Agreement, the Maximum Available Commitment by an amount equal to the amount of the Interest
Advance requested to be made hereby as set forth in clause (i) of paragraph (3) of this Notice of Borrowing and such reduction shall automatically result in corresponding reductions in the amounts available to be borrowed pursuant to a
subsequent Advance. 
 IN WITNESS WHEREOF, the Borrower has executed and delivered this Notice of Borrowing as of the
     day of             ,         . 
  

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, as Subordination Agent, as Borrower
		
	By:	 	  

		 	Name:
		 	Title:

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 I-2 

 SCHEDULE I TO INTEREST ADVANCE NOTICE OF BORROWING 

[Insert Copy of Computations in accordance with Interest Advance Notice of Borrowing] 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 I-3 

 ANNEX II to 

REVOLVING CREDIT AGREEMENT 

FORM OF NON-EXTENSION ADVANCE NOTICE OF BORROWING 

NON-EXTENSION ADVANCE NOTICE OF BORROWING 

The undersigned, a duly authorized signatory of the undersigned subordination agent (the “Borrower”), hereby certifies
to NATIXIS, acting via its New York Branch (the “Liquidity Provider”), with reference to the Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between the Borrower and the Liquidity Provider (the
“Liquidity Agreement”; the terms defined therein and not otherwise defined herein being used herein as therein defined or referenced), that: 

(1) The Borrower is the Subordination Agent under the Intercreditor Agreement. 

(2) The Borrower is delivering this Notice of Borrowing for the making of the Non-Extension Advance by the Liquidity Provider to be used for
the funding of the Class A Cash Collateral Account in accordance with Section 3.05(d) of the Intercreditor Agreement, which Advance is requested to be made on             ,
        . The Non-Extension Advance should be remitted to [insert wire and account details]. 
 (3)
The amount of the Non-Extension Advance requested hereby (i) is $        , which equals the Maximum Available Commitment on the date hereof and is to be applied in respect of the funding of the
Class A Cash Collateral Account in accordance with Sections 3.05(d) and 3.05(f) of the Intercreditor Agreement, (ii) does not include any amount with respect to the payment of the principal of, or premium on, the Class A Certificates,
or principal of, or interest or premium on, the Class B Certificates or any Additional Certificates, if issued, (iii) was computed in accordance with the provisions of the Class A Certificates, the Liquidity Agreement, the
Class A Trust Agreement and the Intercreditor Agreement (a copy of which computation is attached hereto as Schedule I) and (iv) has not been and is not the subject of a prior or contemporaneous Notice of Borrowing under the Liquidity
Agreement. 
 (4) Upon receipt by or on behalf of the Borrower of the amount requested hereby, (a) the Borrower will deposit such
amount in the Class A Cash Collateral Account and apply the same in accordance with the terms of Sections 3.05(d) and 3.05(f) of the Intercreditor Agreement, (b) no portion of such amount shall be applied by the Borrower for any other
purpose and (c) no portion of such amount until so applied shall be commingled with other funds held by the Borrower. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 The Borrower hereby acknowledges that, pursuant to the Liquidity Agreement, (A) the making
of the Non-Extension Advance as requested by this Notice of Borrowing shall automatically and irrevocably terminate the obligation of the Liquidity Provider to make further Advances under the Liquidity Agreement and (B) following the making by
the Liquidity Provider of the Non-Extension Advance requested by this Notice of Borrowing, the Borrower shall not be entitled to request any further Advances under the Liquidity Agreement. 

IN WITNESS WHEREOF, the Borrower has executed and delivered this Notice of Borrowing as of the      day of
            ,         . 
  

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, as Subordination Agent, as Borrower
		
	By:	 	  

		 	Name:
		 	Title:

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 II-2 

 SCHEDULE I TO NON-EXTENSION ADVANCE NOTICE OF BORROWING 

[Insert Copy of computations in accordance with Non-Extension Advance Notice of Borrowing] 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 II-3 

 ANNEX III to 

REVOLVING CREDIT AGREEMENT 

FORM OF DOWNGRADE ADVANCE NOTICE OF BORROWING 

DOWNGRADE ADVANCE NOTICE OF BORROWING 

The undersigned, a duly authorized signatory of the undersigned subordination agent (the “Borrower”), hereby certifies
to NATIXIS, acting via its New York Branch (the “Liquidity Provider”), with reference to the Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between the Borrower and the Liquidity Provider (the
“Liquidity Agreement”; the terms defined therein and not otherwise defined herein being used herein as therein defined or referenced), that: 

(1) The Borrower is the Subordination Agent under the Intercreditor Agreement. 

(2) The Borrower is delivering this Notice of Borrowing for the making of the Downgrade Advance by the Liquidity Provider to be used for the
funding of the Class A Cash Collateral Account in accordance with Section 3.05(c)(iii) of the Intercreditor Agreement by reason of the Liquidity Facility provided under the Liquidity Agreement becoming a Downgraded Facility which has not
been replaced by a Replacement Liquidity Facility, which Advance is requested to be made on             ,         . The Downgrade Advance should be
remitted to [insert wire and account details]. 
 (3) The amount of the Downgrade Advance requested hereby (i) is
$        , which equals the Maximum Available Commitment on the date hereof and is to be applied in respect of the funding of the Class A Cash Collateral Account in accordance with Sections 3.05(c) and
3.05(f) of the Intercreditor Agreement, (ii) does not include any amount with respect to the payment of the principal of, or premium on, the Class A Certificates, or principal of, or interest or premium on, the Class B Certificates or
any Additional Certificates, if issued, (iii) was computed in accordance with the provisions of the Class A Certificates, the Class A Trust Agreement and the Intercreditor Agreement (a copy of which computation is attached hereto as
Schedule I) and (iv) has not been and is not the subject of a prior or contemporaneous Notice of Borrowing under the Liquidity Agreement. 

(4) Upon receipt by or on behalf of the Borrower of the amount requested hereby, (a) the Borrower will deposit such amount in the
Class A Cash Collateral Account and apply the same in accordance with the terms of Sections 3.05(c) and 3.05(f) of the Intercreditor Agreement, (b) no portion of such amount shall be applied by the Borrower for any other purpose and
(c) no portion of such amount until so applied shall be commingled with other funds held by the Borrower. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 The Borrower hereby acknowledges that, pursuant to the Liquidity Agreement, (A) the making
of the Downgrade Advance as requested by this Notice of Borrowing shall automatically reduce, subject to reinstatement in accordance with the terms of the Liquidity Agreement, the Maximum Available Commitment to zero and (B) following the
making by the Liquidity Provider of the Downgrade Advance requested by this Notice of Borrowing, subject to reinstatement in accordance with the terms of the Liquidity Agreement, the Borrower shall not be entitled to request any further Advances
under the Liquidity Agreement. 
 IN WITNESS WHEREOF, the Borrower has executed and delivered this Notice of Borrowing as of the
     day of             ,         . 
  

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, as Subordination Agent, as Borrower
		
	By:	 	  

		 	Name:
		 	Title:

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 III-2 

 SCHEDULE I TO DOWNGRADE ADVANCE NOTICE OF BORROWING 

[Insert Copy of computations in accordance with Downgrade Advance Notice of Borrowing] 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 III-3 

 ANNEX IV to 

REVOLVING CREDIT AGREEMENT 

FORM OF FINAL ADVANCE NOTICE OF BORROWING 

FINAL ADVANCE NOTICE OF BORROWING 

The undersigned, a duly authorized signatory of the undersigned borrower (the “Borrower”), hereby
certifies to NATIXIS, acting via its New York Branch (the “Liquidity Provider”), with reference to the Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between the Borrower and the Liquidity Provider
(the “Liquidity Agreement”; the terms defined therein and not otherwise defined herein being used herein as therein defined or referenced), that: 

(1) The Borrower is the Subordination Agent under the Intercreditor Agreement. 

(2) The Borrower is delivering this Notice of Borrowing for the making of the Final Advance by the Liquidity Provider to be
used for the funding of the Class A Cash Collateral Account in accordance with Section 3.05(i) of the Intercreditor Agreement by reason of the receipt by the Borrower of a Termination Notice from the Liquidity Provider with respect to the
Liquidity Agreement, which Advance is requested to be made on             ,         . The Final Advance should be remitted to [insert wire and
account details]. 
 (3) The amount of the Final Advance requested hereby (i) is
$        , which equals the Maximum Available Commitment on the date hereof and is to be applied in respect of the funding of the Class A Cash Collateral Account in accordance with Sections 3.05(f) and
3.05(i) of the Intercreditor Agreement, (ii) does not include any amount with respect to the payment of principal of, or premium on, the Class A Certificates, or principal of, or interest or premium on, the Class B Certificates or any
Additional Certificates, if issued, (iii) was computed in accordance with the provisions of the Class A Certificates, the Class A Trust Agreement and the Intercreditor Agreement (a copy of which computation is attached hereto as
Schedule I) and (iv) has not been and is not the subject of a prior or contemporaneous Notice of Borrowing. 
 (4)
Upon receipt by or on behalf of the Borrower of the amount requested hereby, (a) the Borrower will deposit such amount in the Class A Cash Collateral Account and apply the same in accordance with the terms of Sections 3.05(f) and 3.05(i)
of the Intercreditor Agreement, (b) no portion of such amount shall be applied by the Borrower for any other purpose and (c) no portion of such amount until so applied shall be commingled with other funds held by the Borrower. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 The Borrower hereby acknowledges that, pursuant to the Liquidity Agreement, (A) the making
of the Final Advance as requested by this Notice of Borrowing shall automatically and irrevocably terminate the obligation of the Liquidity Provider to make further Advances under the Liquidity Agreement and (B) following the making by the
Liquidity Provider of the Final Advance requested by this Notice of Borrowing, the Borrower shall not be entitled to request any further Advances under the Liquidity Agreement. 

IN WITNESS WHEREOF, the Borrower has executed and delivered this Notice of Borrowing as of the      day of
            ,         . 
  

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, as Subordination Agent, as Borrower
		
	By:	 	  

		 	Name:
		 	Title:

 [* Bracketed language may be included at Borrower’s option.] 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 IV-2 

 SCHEDULE 1 TO FINAL ADVANCE NOTICE OF BORROWING 

[Insert Copy of Computations in accordance with Final Advance Notice of Borrowing] 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 IV-3 

 ANNEX V to 

REVOLVING CREDIT AGREEMENT 
 FORM
OF SPECIAL TERMINATION 
 ADVANCE NOTICE OF BORROWING 

SPECIAL TERMINATION ADVANCE NOTICE OF BORROWING 

The undersigned, a duly authorized signatory of the undersigned borrower (the “Borrower”), hereby certifies to
NATIXIS, acting via its New York Branch (the “Liquidity Provider”), with reference to the Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between the Borrower and the Liquidity Provider (the
“Liquidity Agreement”; the terms defined therein and not otherwise defined herein being used herein as therein defined or referenced), that: 

(1) The Borrower is the Subordination Agent under the Intercreditor Agreement. 

(2) The Borrower is delivering this Notice of Borrowing for the making of the Special Termination Advance by the Liquidity
Provider to be used for the funding of the Class A Cash Collateral Account in accordance with Section 3.05(k) of the Intercreditor Agreement by reason of the receipt by the Borrower of a Special Termination Notice from the Liquidity
Provider with respect to the Liquidity Agreement, which Advance is requested to be made on                     . 

(3) The amount of the Special Termination Advance requested hereby (i) is
$        , which equals the Maximum Available Commitment on the date hereof and is to be applied in respect of the funding of the Class A Cash Collateral Account in accordance with Sections 3.05(f)
and 3.05(k) of the Intercreditor Agreement, (ii) does not include any amount with respect to the payment of principal of, or premium on, the Class A Certificates, or principal of, or interest or premium on, the Class B
Certificates or any Additional Certificates, if issued, (iii) was computed in accordance with the provisions of the Class A Certificates, the Class A Trust Agreement and the Intercreditor Agreement (a copy of which computation is
attached hereto as Schedule I) and (iv) has not been and is not the subject of a prior or contemporaneous Notice of Borrowing. 

(4) Upon receipt by or on behalf of the Borrower of the amount requested hereby, (a) the Borrower shall deposit such
amount in the Class A Cash Collateral Account and apply the same in accordance with the terms of Sections 3.05(f) and 3.05(k) of the Intercreditor Agreement, (b) no portion of such amount shall be applied by the Borrower for any other
purpose and (c) no portion of such amount until so applied shall be commingled with other funds held by the Borrower. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 The Borrower hereby acknowledges that, pursuant to the Liquidity Agreement, (A) the making
of the Special Termination Advance as requested by this Notice of Borrowing shall automatically and irrevocably terminate the obligation of the Liquidity Provider to make further Advances under the Liquidity Agreement; and (B) following the
making by the Liquidity Provider of the Special Termination Advance requested by this Notice of Borrowing, the Borrower shall not be entitled to request any further Advances under the Liquidity Agreement. 

IN WITNESS WHEREOF, the Borrower has executed and delivered this Notice of Borrowing as of the      day of
            ,         . 
  

			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, as Subordination Agent, as Borrower
		
	By:	 	  

		 	Name:
		 	Title:

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 V-2 

 SCHEDULE 1 TO SPECIAL TERMINATION ADVANCE NOTICE OF BORROWING 

[Insert Copy of Computations in accordance with Special Termination Advance Notice of Borrowing] 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 V-3 

 ANNEX VI to 

REVOLVING CREDIT AGREEMENT 

FORM OF NOTICE OF TERMINATION 

NOTICE OF TERMINATION 

[Date] 
 Wilmington Trust,
National Association, 
 as Subordination Agent, 

as Borrower 
 1100 North Market Street 

Wilmington, Delaware 19890-1605 
 Reference: Spirit Airlines
2015-1A EETC 
 Attention: Corporate Trust Administration – Melinda Romay 

Telephone: (302) 636-6387 
 Facsimile: (302) 636-4140

  

	Re:	Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Spirit Airlines Pass Through Trust 2015-1A, as
Borrower, and Natixis, acting via its New York Branch (the “Liquidity Agreement”) 

 Ladies and Gentlemen: 

You are hereby notified that pursuant to Section 6.01(a) of the Liquidity Agreement, by reason of the occurrence and continuance of a
Liquidity Event of Default and the existence of a Performing Note Deficiency (each as defined in the Liquidity Agreement), we are giving this notice to you in order to cause (i) our obligations to make Advances (as defined in the Liquidity
Agreement) under such Liquidity Agreement to terminate on the fifth Business Day after the date on which you receive this notice and (ii) you to request a Final Advance under the Liquidity Agreement pursuant to Section 2.02(c) of the
Liquidity Agreement and Section 3.05(i) of the Intercreditor Agreement (as defined in the Liquidity Agreement) as a consequence of your receipt of this notice. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 THIS NOTICE IS THE “NOTICE OF TERMINATION” PROVIDED FOR UNDER THE LIQUIDITY
AGREEMENT. OUR OBLIGATIONS TO MAKE ADVANCES UNDER THE LIQUIDITY AGREEMENT WILL TERMINATE ON THE FIFTH BUSINESS DAY AFTER THE DATE ON WHICH YOU RECEIVE THIS NOTICE. 

 

			
	Very truly yours,
	
	NATIXIS, ACTING VIA ITS NEW YORK BRANCH,
as Liquidity Provider
		
	By:	 	  

		 	Name:
		 	Title:
		
	By:	 	  

		 	Name:
		 	Title:

  

	cc:	Wilmington Trust, National Association, as Class A Trustee 

 Spirit Airlines, Inc. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 VI-2 

 ANNEX VII to 

REVOLVING CREDIT AGREEMENT 

FORM OF NOTICE OF SPECIAL TERMINATION 

NOTICE OF SPECIAL TERMINATION 

[Date] 
 Wilmington Trust, National Association,

 as Subordination Agent, 
 as
Borrower 
 1100 North Market Street 
 Wilmington, Delaware
19890-1605 
 Reference: Spirit Airlines 2015-1A EETC 

Attention: Corporate Trust Administration – Melinda Romay 

Telephone: (302) 636-6387 
 Facsimile: (302) 636-4140

  

	Re:	Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Spirit Airlines Pass Through Trust 2015-1A, as
Borrower, and Natixis, acting via its New York Branch (the “Liquidity Agreement”) 

 Ladies and Gentlemen: 

You are hereby notified that pursuant to Section 6.01(b) of the Liquidity Agreement, by reason of the aggregate Pool Balance of the
Class A Certificates exceeding the aggregate outstanding principal amount of the Series A Equipment Notes (other than any Series A Equipment Notes previously sold or with respect to which the Aircraft related to such Series A
Equipment Notes has been disposed of) during the 18-month period prior to April 1, 2028, we are giving this notice to you in order to cause (i) our obligations to make Advances (as defined in the Liquidity Agreement) under such Liquidity
Agreement to terminate on the fifth Business Day after the date on which you receive this notice and (ii) you to request a Special Termination Advance under the Liquidity Agreement pursuant to Section 2.02(d) of the Liquidity Agreement and
Section 3.05(k) of the Intercreditor Agreement (as defined in the Liquidity Agreement) as a consequence of your receipt of this notice. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

 THIS NOTICE IS THE “NOTICE OF SPECIAL TERMINATION” PROVIDED FOR UNDER THE LIQUIDITY
AGREEMENT. OUR OBLIGATIONS TO MAKE ADVANCES UNDER THE LIQUIDITY AGREEMENT WILL TERMINATE ON THE FIFTH BUSINESS DAY AFTER THE DATE ON WHICH YOU RECEIVE THIS NOTICE. 

 

			
	Very truly yours,
	
	 NATIXIS, ACTING VIA ITS NEW YORK BRANCH,

as Liquidity Provider

		
	By:	 	  

		 	Name:
		 	Title:
		
	By:	 	  

		 	Name:
		 	Title:

  

	cc:	Wilmington Trust, National Association, as Class A Trustee 

 Spirit Airlines, Inc. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 VII-2 

 ANNEX VIII to 

REVOLVING CREDIT AGREEMENT 

FORM OF NOTICE OF REPLACEMENT SUBORDINATION AGENT 

NOTICE OF REPLACEMENT SUBORDINATION AGENT 

[Date] 
 Attention: 

 

	Re:	Revolving Credit Agreement (2015-1A), dated as of August 11, 2015, between Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Spirit Airlines Pass Through Trust 2015-1A, as
Borrower, and Natixis, acting via its New York Branch (the “Liquidity Agreement”) 

 Ladies and Gentlemen: 

For value received, the undersigned beneficiary hereby irrevocably transfers to: 

[Name of Transferee] 
 [Address of
Transferee] 
 all rights and obligations of the undersigned as Borrower under the Liquidity Agreement referred to above. The transferee has succeeded the
undersigned as Subordination Agent under the Intercreditor Agreement referred to in the first paragraph of the Liquidity Agreement, pursuant to the terms of Section 7.01 of the Intercreditor Agreement. 

By this transfer, all rights of the undersigned as Borrower under the Liquidity Agreement are transferred to the transferee and the transferee
shall hereafter have the sole rights and obligations as Borrower thereunder. The undersigned shall pay any costs and expenses of such transfer, including, but not limited to, transfer taxes or governmental charges. 

This transfer shall be effective as of [specify time and date]. 

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 VIII-1 

 
			
	WILMINGTON TRUST, NATIONAL ASSOCIATION, as Subordination Agent, as Borrower
		
	By:	 	  

		 	Name:
		 	Title:

  
 Revolving Credit
Agreement (Class A) 
 (Spirit 2015-1 EETC) 

  
 VIII-2

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