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                                                                    EXHIBIT 4.12
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                           AIRTRAN AIRLINES, INC., 
                                  as Issuer, 

                          AIRTRAN HOLDINGS, INC. AND
                 THE SUBSIDIARY GUARANTORS SIGNATORIES HERETO,
                                as Guarantors,

                            AIRTRAN AIRWAYS, INC.,
                                 as Guarantor

                                      and

                            THE BANK OF NEW YORK, 
                       as Trustee and Collateral Trustee

                           ________________________

                         FIRST SUPPLEMENTAL INDENTURE

                         Dated as of November 17, 1997

                                      to 

                                   INDENTURE

                          Dated as of August 13, 1997

                            -----------------------

                     10 1/2% Senior Secured Notes due 2001

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                         FIRST SUPPLEMENTAL INDENTURE

     FIRST SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as of 
                                         ----------------------
November 17, 1997, by and among AirTran Airlines, Inc., a Nevada corporation 
(the "Company"), AirTran Holdings, Inc., a Nevada corporation (the "Parent 
      -------                                                       ------
Company"), the Subsidiary Guarantors parties hereto (the "Guarantors"), AirTran 
-------                                                   ----------
Airways, Inc., a Delaware corporation ("Airways") and The Bank of New York, as 
                                        -------
trustee and collateral trustee (the "Trustee").
                                     -------

                                   RECITALS

     WHEREAS, the Company, the Parent Company and the Guarantors have heretofore
executed and delivered to the Trustee an Indenture, dated as of August 13, 1997 
(the "Indenture"), providing for the issuance of an aggregate principal amount 
      ---------
of $80,000,000 of 10 1/2% Senior Secured Notes due 2001 (the "Notes"); and
                                                              -----

     WHEREAS, pursuant to the merger of Airways Corporation with and into the 
Parent Company as of November 17, 1997 (the "Merger"), Airways, which had 
                                             ------
theretofore been a wholly-owned subsidiary of Airways Corporation, became a 
wholly-owned subsidiary of the Parent Company; and 

     WHEREAS, pursuant to the Merger, Airways became a Restricted Subsidiary of 
the Parent Company; and

     WHEREAS, pursuant to the terms of the Indenture, the Parent Company will
cause each Restricted Subsidiary to become a Subsidiary Guarantor of the Notes; 
and

     WHEREAS, pursuant to Section 901 of the Indenture, the Company and the
Trustee may enter into one or more supplemental indentures without the consent 
of any Holders to add new Subsidiary Guarantors and to make certain other 
changes to the Indenture; and

     WHEREAS, in anticipation of the Merger, the Company changed its name from 
"ValuJet Airlines, Inc." to AirTran Airlines, Inc."; and 

     WHEREAS, in connection with the Merger, the Parent Company changed its name
from "ValuJet, Inc." to "AirTran Holdings, Inc."; and

     WHEREAS, the Indenture provides for the execution and delivery of a 
supplement to the Indenture which shall particularly describe the Engines being 
specifically mortgaged to the Trustee for the benefit and security of the 
Holders pursuant to the Indenture; and

     WHEREAS, the Indenture relates to certain Airframes and Engines more 
particularly described therein, which Indenture was recorded with the FAA on 
November 4, 1997 and given Conveyance No. GG011890; and
 
     WHEREAS, it is the desire of the Trustee and the Company to add Collateral 
under the Indenture one (1) McDonnell Douglas DC-9-32 aircraft, registration 
number N913VV and serial number 47318 (the "Replacement Aircraft") along with 
                                            --------------------
its two (2) related Pratt & Whitney JT8D-9 aircraft

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engines bearing serial numbers 665721 and 666135, and one (1) additional Pratt &
Whitney JT8D-9 aircraft engine bearing serial number 666060 (which three
aircraft engines are referred to herein collectively as the "Replacement
                                                             -----------
Engines"), in replacement of and substitution for one (1) McDonnell Douglas 
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DC-9-32 aircraft, registration number N960VV and serial number 47067 (the 
"Released Aircraft") and three (3) Pratt & Whitney JT8D-9 Engines bearing 
 -----------------
serial numbers 665820, 665470 and 666974 (the "Released Engines");
                                               -----------------

     NOW THEREFORE, in consideration of the foregoing and for other good and 
valuable consideration, the receipt of which is hereby acknowledged, the 
Company, the Parent Company, the Guarantors, Airways and the Trustee mutually 
covenant and agree for the equal and ratable benefit of the Holders of the Notes
as follows:

     1.   Definitions. Capitalized terms used herein without definition shall 
          -----------
have the meanings assigned to them in the Indenture. For all purposes of this 
Supplemental Indenture, except as otherwise herein expressly provided or unless 
the context otherwise requires, the words "herein," hereof," and "hereby" and
other words of similar import used in this Supplemental Indenture refer to this
Supplemental Indenture as a whole and not to any particular section hereof.

     2.   Guarantee. Airways hereby (i) becomes, and subject to the provisions 
          ---------
of the Indenture, after the date hereof shall be, a Subsidiary Guarantor, and 
(ii) subjects itself to the provisions (including the representations and 
warranties) of the Indenture as a Subsidiary Guarantor, and agrees to be bound 
thereby. In furtherance of the foregoing, and not in limitation thereof, 
pursuant to Section 1401 of the Indenture, Airways hereby jointly and severally 
with the Parent Company and all other Guarantors unconditionally guarantees to 
each Holder of a Security authenticated and delivered by the Trustee, and to the
Trustee on behalf of such Holder, the due and punctual payment of the principal
of (and premium, if any) and interest on such Security when and as the same
shall become due and payable, whether at the Stated Maturity or by acceleration,
call for redemption, purchase or otherwise, in accordance with the terms of such
Security and of the Indenture. In case of the failure of the Company punctually
to make any such payment, Airways hereby jointly and severally agrees with the
Parent Company and all other Guarantors to cause such payment to be made
punctually when and as the same shall become due and payable, whether at the
Stated Maturity or by acceleration, call for redemption, purchase or otherwise,
and as if such payment were made by the Company.

     3.   Change of Corporate Names. Any and all references in the Indenture to
          -------------------------
VALUJET, INC. shall be changed to AIRTRAN HOLDINGS, INC. and any and all 
references to VALUJET AIRLINES, INC. shall be changed to AIRTRAN AIRLINES, INC.

     4.   Substitute Security.
          -------------------

          (a)  To secure the prompt payment of the principal amount of and 
interest on, and all other amounts due with respect to, all Securities from time
to time outstanding under the Indenture and the performance and observance by 
the Company of all the agreements, covenants and provisions contained in the 
Indenture for the benefit and security of the Holders under the Indenture and 
the prompt payment of any and all amounts from time to time owing under the 
Indenture by the Company to the Trustee, the Company does hereby effective as of
July 23, 1998, grant, sell, assign, transfer, convey, pledge and confirm unto 
the Trustee, its successors and assigns, for the benefit and security of the 
Holders and the Trustee, a first priority security interest in all estate,
right, title and interest of the

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Company in and to the Replacement Aircraft and Replacement Engines (each such
engine having 750 or more rated takeoff horsepower or the equivalent thereof)
together with all equipment and accessories, parts and appurtenances pertaining
or attached to the Replacement Aircraft and Replacement Engines whether now
owned or hereafter acquired and all substitutions, modifications, improvements,
accessions and accumulations to the New Engine and all warranties of any
manufacturer with respect thereto.

          (b)  As evidence of the releasing of all right, title and interest of 
the Trustee in, to and under the Released Aircraft and Released Engines, the 
Trustee shall execute effective as of July 23, 1998, a separate Partial Release 
and any other document reasonably requested by the Company to evidence such 
release.

          (c)  The Company hereby acknowledges that the Replacement Aircraft and
Replacement Engines referred to in this Supplemental Indenture are owned by and 
have been delivered to the Company and are included in the property of the 
Company subject to the pledge and mortgage thereof under the Indenture.

     5.   Ratification of Indenture: Supplemental Indentures Part of Indenture. 
          --------------------------------------------------------------------
Except as expressly amended hereby, the Indenture is in all respects ratified 
and confirmed and all the terms, conditions and provisions thereof shall remain 
in full force and effect.  This Supplemental Indenture shall form a part of the 
Indenture for all purposes, and every Holder of Notes heretofore or hereafter 
authenticated and delivered shall be bound hereby.

     6.   Governing Law.  THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND 
          -------------   
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, AS APPLIED TO 
CONTRACTS MADE AND PERFORMED WITHIN THE STATE OF NEW YORK, WITHOUT REGARD TO 
PRINCIPLES OF CONFLICTS OF LAW.
          
     7.   Trustee Makes No Representation. The Trustee makes no representation
          -------------------------------
as to the validity or sufficiency of this Supplemental Indenture.

     8.   Counterparts.  The parties may sign any number of copies of this 
          ------------
Supplemental Indenture.  Each signed copy shall be an original, but all of them 
together represent the same agreement.

     9.   Effect of Headings. The Section headings herein are for convenience
          ------------------
only and shall not affect the construction thereof.

     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.


                                           AIRTRAN AIRWAYS, INC., as Guarantor


                                           By:     /s/ D. Joseph Corr  
                                               -----------------------   
                                                Name:  D. Joseph Corr     
                                                Title: President      
                                        
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                                             AIRTRAN AIRLINES, INC., the Company

                                             
                                             By:   /s/ D. Joseph Corr 
                                                 -------------------------------
                                                   Name:  D. Joseph Corr    
                                                   Title: President


                                             AIRTRAN HOLDINGS, INC., the Parent
                                             Company


                                             By:   /s/ D. Joseph Corr
                                                 -------------------------------
                                                   Name:  D. Joseph Corr
                                                   Title: President


                                             THE BANK OF NEW YORK, as Trustee
                                             and Collateral Trustee


                                             By:   /s/ Marie E. Trimboli 
                                                 -------------------------------
                                                   Name:  MARIE E. TRIMBOLI 
                                                   Title: Assistant Treasurer


                                             VALUJET MANAGEMENT CORP., as 
                                             Guarantor


                                             By:   /s/ D. Joseph Corr
                                                 -------------------------------
                                                   Name:  D. Joseph Corr 
                                                   Title: President


                                             VALUJET INVESTMENT CORP., as 
                                             Guarantor


                                             By:   /s/ D. Joseph Corr
                                                 -------------------------------
                                                   Name:  D. Joseph Corr
                                                   Title: President


                                             VALUJET CAPITAL CORP., as Guarantor


                                             By:   /s/ D. Joseph Corr
                                                 -------------------------------
                                                   Name:  D. Joseph Corr   
                                                   Title: President

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