Exhibit 99.5  FOURTH AMENDMENT TO REIMBURSEMENT,
CREDIT AND SECURITY AGREEMENT  THIS
FOURTH AMENDMENT TO REIMBURSEMENT, CREDIT AND
SECURITY AGREEMENT (this Amendment) is made as of this 29th day of January, 2007, by and between
INNOVATIVE SOLUTIONS AND SUPPORT, LLC (the Borrower) and PNC BANK, NATIONAL
ASSOCIATION (the Bank).  RECITALS:  A.The Bank and the Borrower entered into a
Reimbursement, Credit and Security Agreement dated as of August 1, 2000,
as amended by an Amendment dated as of November 29, 2002, an Amendment to
Loan Documents dated as of March 30, 2004 and as further amended by a
Third Amendment to Reimbursement, Credit and Security Agreement and Waiver
dated as of July 25, 2006 (as so amended, the Agreement), pursuant to
which the Bank has issued a letter of credit for the account of the Borrower in
connection with the issuance of certain industrial development revenue bonds on
behalf of the Borrower.  B.The Borrower has requested that the Bank
amend certain financial covenants in the Agreement and the Bank has agreed to
amend the Agreement on the terms and subject to the conditions set forth
herein.  NOW, THEREFORE,in consideration of the foregoing and for
good and valuable consideration, the legality and sufficiency of which is hereby
acknowledged, the parties hereto, intending to be legally bound hereby, agree
as follows:  1.Definitions.  Capitalized
terms used herein and not otherwise defined herein shall have the meanings
assigned to them in the Agreement.  2.Amendment
to Agreement.  The Agreement is hereby amended effective as
of the date hereof as follows:  (a)Section 6.21(a) is hereby amended
and restated to read in full as follows:  (a)IS&S, Inc. will maintain, on a consolidated basis, as
of the end of each fiscal quarter of IS&S, Inc. beginning with the
fiscal quarter ending on June 30, 2008, a ratio of total liabilities to
EBITDA of not greater than 2.25:1.00.  (b)Section 6.21(b) is hereby amended
and restated to read in full as follows:  (b)IS&S, Inc. will maintain, on a consolidated basis, as of the
end of each fiscal quarter of IS&S, Inc. beginning with the fiscal
quarter ending on June 30, 2008, a Fixed Charge Ratio equal to or greater
than 1.25:1.00.  3.Amendments
to the Other Documents.  All references to the Agreement in the Collateral
Documents or the Bond Documents and in any documents executed in connection therewith shall be deemed to refer
to the Agreement as amended by this Amendment.


4.Ratification
of the Other Documents.  Notwithstanding
anything to the contrary herein contained or any claims of the parties to the
contrary, the Bank and the Borrower agree that the Agreement and the Collateral
Documents and each of the documents executed in connection therewith are in
full force and effect and each such document shall remain in full force and
effect, as further amended by this Amendment, and the Borrower hereby ratifies
and confirms its obligations thereunder.  5.Representations
and Warranties.  (a)The
Borrower hereby certifies that (i) the representations and warranties of the
Borrower in the Agreement are true and correct in all material respects as of
the date hereof, as if made on the date hereof and (ii) no Event of
Default and no event which could become an Event of Default with the passage of
time or the giving of notice, or both, under the Agreement or the Collateral
Documents exists on the date hereof.  (b)The
Borrower further represents that it has all the requisite power and authority
to enter into and to perform its obligations under this Amendment, and that the
execution, delivery and performance of this Amendment have been duly authorized
by all requisite action and will not violate or constitute a default under any
provision of any applicable law, rule, regulation, order, writ, judgment,
injunction, decree, determination or award
presently in effect or of the organizational documents of the Borrower, or of
any indenture, note, loan or credit agreement, license or any other agreement,
lease or instrument to which the Borrower is a party or by which the Borrower
or any of its properties is bound.  (c)The
Borrower also further represents that the Borrowers reimbursement obligation
under the Agreement is absolute and unconditional, and there exists no right of
set off or recoupment, counterclaim or defense of any nature whatsoever to
payment of such obligations.  6.Conditions
Precedent.  The amendments set
forth herein shall be effective as of the date hereof upon the fulfillment, to
the satisfaction of the Bank and its counsel, of the following conditions
precedent:  (a)The
Borrower shall have delivered to the Bank the following, all of which shall be
in form and substance satisfactory to the Bank and shall be duly completed and
executed:  (i)a fully executed
counterpart of this Amendment, including the Consent of Guarantors; and  (ii)such additional
documents, certificates and information as the Bank may reasonably request.  (b)The
Borrower shall have paid to the Bank a nonrefundable modification fee in the
amount of $2,500.  (c)The
representations and warranties set forth in the Agreement shall be true and
correct on and as of the date hereof.  2


(d)No
Event of Default, and no event which, with the passage of time or the giving of
notice, or both, would become such an Event of Default shall have occurred and
be continuing as of the date hereof.  7.No Waiver.  This Amendment does not and shall not be
deemed to constitute a waiver by the Bank of any Event of Default, or of any
event which with the passage of time or the giving of notice or both would
constitute an Event of Default, nor does it obligate the Bank to agree to any
further modifications to the Agreement or the Collateral Documents or
constitute a waiver of any of the Banks other rights or remedies.  8.Release and Indemnity.  (a) Recognizing and in consideration of
the Banks agreement to the amendments provided herein, the Borrower hereby
waives and releases the Bank and its officers, attorneys, agents, directors,
and employees from any liability, suit, damage, claim, actions, counterclaims
or offsets, loss or expense of any kind or nature whatsoever and howsoever
arising, whether known or unknown and whether based on facts now known or
unknown, direct or derivative, that the Borrower, or anyone claiming in a
derivative capacity from the Borrower, ever had or has as of the date of this
Amendment against any of them including, without limitation, any of the
foregoing arising out of or relating to the Banks or such other Persons acts
or omissions with respect to this Amendment, the other documents executed in
connection herewith, the Agreement, the Collateral Documents, the Bond
Documents or any other matters described or referred to herein or therein.  (b)The
Borrower further hereby agrees to indemnify and hold the Bank and its officers,
attorneys, agents, directors and employees harmless from any loss, damage,
judgment, liability or expense (including counsel fees) suffered by or rendered
against the Bank or any of them on account of anything arising out of this
Amendment, the Agreement, the Collateral Documents, the Bond Documents or any
other document or instrument delivered pursuant hereto or thereto up to and
including the date of this Amendment; provided that, the
Borrower shall not have any obligation hereunder to the Bank or such other
Person with respect to indemnified liabilities arising from the gross
negligence or willful misconduct of the Bank or such other Person.  9.Costs and Expenses.The Borrower will pay to the Bank on
demand all costs and expenses of the Bank incurred in connection with the
preparation, execution and delivery of this Amendment, including, without
limitation, the reasonable fees and expenses of counsel for the Bank with
respect thereto.  3


10.Miscellaneous.  (a)All
terms, conditions, provisions and covenants in the Agreement and the Collateral
Documents and all other documents delivered to the Bank in connection therewith
shall remain unaltered and in full force and effect except as modified or
amended hereby. To the extent that any term or provision of this Amendment is
or may be deemed expressly inconsistent with any term or provision in the
Agreement or any Collateral Document or any other document executed in
connection therewith, the terms and provisions hereof shall control.  (b)This
Amendment constitutes the entire agreement of the parties with respect to the
subject matter hereof and supersedes all prior and contemporaneous
understandings and agreements.  (c)In
the event any provisions of this Amendment shall be held invalid or
unenforceable by any court of competent jurisdiction, such holding shall not
invalidate or render unenforceable any other provision hereof.  (d)This
Amendment shall be governed by and construed according to the laws of the
Commonwealth of Pennsylvania.  (e)This
Amendment, and the Agreement and Collateral Documents as amended hereby, shall
inure to the benefit of, and be binding upon, the parties hereto and thereto
and their respective successors and assigns and may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.  (f)The
headings used in this Amendment are for convenience of reference only, do not
form a part of this Amendment and shall not affect in any way the meaning or
interpretation of this Amendment.  [Signatures to appear on the following page]  4


IN WITNESS WHEREOF, the parties hereto have executed this Fourth
Amendment to Reimbursement, Credit and Security Agreement as of the day and
year first above written.   INNOVATIVE SOLUTIONS AND
  SUPPORT, LLCBy:
  Innovative Solutions and Support,Incorporated, its sole member andmanager  By:
  /s/ James ReillyName: James ReillyTitle:   CFO   PNC BANK, NATIONAL ASSOCIATIONBy:
  /s/John
  M DiNapoliName:
  John
  M DiNapoliTitle:
  Sr. Vice President  S-1


CONSENT OF GUARANTORS  Each of the undersigned guarantors (the Guarantors)
consents to the provisions of the foregoing Fourth Amendment to Reimbursement,
Credit and Security Agreement (the Amendment) and confirms and agrees that: (a) such
Guarantors obligations under its Guaranty and Surety Agreement dated as of August 1,
2000 (as the same has teen amended, the Guaranty), relating to the
obligations of the Borrower to the Bank shall be unimpaired by the Amendment; (b) such
Guarantor has no defenses, set offs, counterclaims, discounts or charges of any
kind against the Bank, its officers, directors, employees, agents or attorneys
with respect to the Guaranty; and (c) all of the terms, conditions and
covenants in the Guaranty remain unaltered and in full force and effect and are
hereby ratified and confirmed and apply to the obligations of the Borrower to
the Bank, as modified by the Amendment. Each of the Guarantors certifies that
all representations and warranties made by it in the Guaranty are true and
correct as of the date of the Amendment.  Each of the Guarantors ratifies and confirms the
indemnification, confession of judgment and waiver of jury trial provisions, if
any, contained in the Guaranty.  WITNESS the due execution of this Consent as a document under seal as
of the date of the Amendment, intending to be legally bound hereby.  INNOVATIVE SOLUTIONS AND
  SUPPORT, INC.By:
  /s/ James ReillyName: James ReillyTitle:   CFO   IS&S DELAWARE, INC.By:
  /s/ James ReillyName: James ReillyTitle:   CFO


THIRD AMENDMENT TO REIMBURSEMENT, CREDIT AND SECURITY
AGREEMENT AND WAIVER  THIS
THIRD AMENDMENT TO REIMBURSEMENT, CREDIT AND SECURITY AGREEMENT AND WAIVER
(this Amendment) is made as of this 25th day of July, 2006, by and between INNOVATIVE
SOLUTIONS AND SUPPORT, LLC (the Borrower)
and PNC BANK, NATIONAL ASSOCIATION (the Bank).  RECITALS:  A.The Bank and the Borrower entered into a
Reimbursement, Credit and
Security Agreement dated as of August 1, 2000, as amended by
an Amendment dated as of November 29, 2002 and as further amended by an
Amendment dated as of March 20, 2004 (as the same may be amended, restated or further modified and in
effect from time to time, the Agreement), pursuant to which the Bank agreed
to issue a letter of credit for the account of the Borrower in connection with
the issuance of certain industrial development revenue bonds on behalf of the Borrower.  B.The Borrower has requested the Bank waive
compliance with certain financial
covenants and amend certain
reporting requirements and financial covenants in the Agreement and the Bank
has agreed to provide said waiver and amend the Agreement on the terms and
subject to the conditions set forth herein.  NOW, THEREFORE,in consideration of the foregoing and for
good and valuable consideration, the legality and sufficiency of which is
hereby acknowledged, the parties hereto, intending to be legally bound hereby, agree as follows:  1.Definitions.Capitalized terms used herein and not
otherwise defined herein shall have
the meanings assigned to them in the Agreement.  2.Waivers.The Borrower has advised the Bank that IS&S, Inc. was in
violation of (i) the total liabilities to EBITDA covenant contained in Section 6.21(a) of the Agreement, (ii) the Fixed Charge Ratio
covenant contained in Section 6.21(b) of
the Agreement, and (iii) the minimum Tangible Net Worth covenant contained
in Section 6.21(c) of the Agreement each as of the end of the fiscal
quarter of IS&S, Inc. ending on June 30, 2006. At the Borrowers request, the Bank hereby waives IS&S, Incsviolation
of the covenants contained in Section 6 21(a), Section 6.21(b) and
Section 6.21(c) for the
fiscal quarter ending on June
30, 2006 and the resulting Events
of Default arising there from.  The
foregoing waivers shall not be
deemed to operate as or obligate the Bank to grant any future waiver or modification of the provisions
of Section 6.21(a), Section 6.21(b) or
Section 6.21(c) for any other fiscal period or of any other term,
condition or Event of Default under the Agreement.


3.Amendment to Agreement.  The
Agreement is hereby amended effective as of the date hereof as follows:  (a)Section 6.10(a)(1) is hereby
amended and restated to read in full as follows:  (1)  audited consolidated and
consolidating financial statements for IS&S, Inc. and its
subsidiaries, including a consolidated balance sheet and related consolidated
statements of income, retained earnings, cash flows, and changes in financial
position as of the end of such Fiscal Year and for such Fiscal Year, audited by
independent certified public accountants acceptable to the Bank and prepared in
accordance with GAAP, which shall fairly present the consolidated financial
condition of IS&S, Inc. and its subsidiaries as at the end of such
Fiscal Year; and  (b)Section 6.21 is hereby amended and
restated to read in full as follows:  Section 6.21 Financial Covenants.  The Borrower shall cause IS&S, Inc.
to observe the following covenants:  (a)IS&S, Inc. will maintain, on a
consolidated basis, as of the end of
each fiscal quarter of IS&S, Inc. beginning with the fiscal quarter
ending on June 30, 2007, a ratio of total liabilities to EBITDA of not
greater than 2.25:1.00.  (b)IS&S, Inc.
will maintain, on a consolidated basis, as of the end of each
fiscal quarter of IS&S, Inc. beginning with the fiscal quarter ending on June 30,
2007, a Fixed Charge Ratio equal to or greater than 1.25:1.00.  (c)IS&S, Inc. will maintain, on a
consolidated basis, at all times a minimum Tangible Net Worth of $65,000,000.  4.Amendments to the OtherDocuments.  All references to the Agreement in the Collateral Documents or the Bond Documents and in any documents executed in connection therewith shall be deemed to refer to the Agreement as
amended by this Amendment.  5.Ratification of the Other
Documents.  Notwithstanding anything to the contrary herein
contained or any claims of the parties to the contrary, the Bank and the
Borrower agree that the Agreement and the Collateral Documents and each of the
documents executed in connection therewith are in full force and effect and
each such document shall remain in full force and effect, as further amended by
this Amendment, and the Borrower
hereby ratifies and confirms its
obligations thereunder.  6.Representations and
Warranties.  (a)The Borrower hereby certifies that (i) the
representations and warranties of
the Borrower in the Agreement are true and correct in all material respects as
of the date hereof, as if made on the date hereof and (ii) no Event of
Default and no event which could become an  2


Event
of Default with the passage of time or the giving of notice, or both, under the
Agreement or the Collateral Documents exists on the date hereof.  (b)The Borrower further represents that it has
all the requisite power and authority to enter into and to perform its
obligations under this Amendment, and that the execution, delivery and
performance of this Amendment have been duly authorized by all requisite action and will not violate or
constitute a default under any provision of any applicable law, rule,
regulation, order, writ, judgment,
injunction, decree, determination or award presently in effect or of the organizational documents of
the Borrower, or of any indenture, note, loan or credit agreement,
license or any other agreement, lease or instrument to which the Borrower is a
party or by which the Borrower or any
of its properties is bound.  (c)The Borrower also further represents that the
Borrowers reimbursement obligation under the Agreement is absolute and
unconditional, and there exists no right of set off or recoupment, counterclaim
or defense of any nature whatsoever to payment of such obligations.  7.Conditions Precedent.  The amendments set forth herein shall be
effective as of the date hereof upon the fulfillment, to the satisfaction of the Bank and its
counsel, of the following conditions precedent:  (a)The Borrower shall have delivered to the Bank
the following, all of which shall be in form and substance satisfactory to the
Bank and shall be duly completed and
executed:  (i)a fully executed counterpart of this
Amendment, including the Consent of Guarantors; and  (ii)such additional documents,
certificates and information as the Bank may reasonably request  (b)The representations and warranties set forth
in the Agreement shall be true and correct on and as of the date hereof.  (c)No Event of Default hereunder, and no event
which, with the passage of time or the giving of notice, or both, would become
such an Event of Default shall have occurred and be continuing as of the date
hereof, except for those which are being waived pursuant to Section 2
hereof.  8.No Waiver.This Amendment does not and shall not be
deemed to constitute a waiver by the
Bank of any Event of Default, or of any event which with the passage of
time or the giving of notice or both
would constitute an Event of Default, nor does it obligate the Bank to agree to
any further modifications to the Agreement or the Collateral
Documents or constitute a waiver
of any of the Banks other rights or remedies.  9.Releaseand Indemnity.(a) Recognizing and in consideration of the Banks agreement to
the amendments provided herein, the Borrower hereby waives and releases the Bank
and its officers, attorneys, agents, directors, and employees from any
liability, suit,  3


damage,
claim, actions, counterclaims or offsets, loss or expense of any kind or nature
whatsoever and howsoever arising, whether known or unknown and whether basedon
factsnow known or unknown,
direct or derivative, that the Borrower, or anyone claiming in a derivative
capacity from the Borrower, ever had or has as of the date of this Amendment
against any of them including, without limitation, any of the foregoing arising
out of or relating to the Banks or such other Persons acts or omissions with
respect to this Amendment, the other documents executed in connection herewith,
the Agreement, the Collateral Documents, the Bond Documents or any other
matters described or referred to
herein or therein.  (b)The Borrower further hereby agrees to
indemnify and hold the Bank and its respective officers, attorneys, agents,
directors and employees harmless from any loss, damage, judgment, liability or
expense (including counsel fees) suffered by or rendered against the Bank
or any of them on account of anything arising out of this Amendment, the Agreement, the Collateral Documents, the Bond
Documents or any other document or instrument delivered pursuant hereto or
thereto up to and including the date of this Amendment; provided that, the Borrower shall not have any obligation
hereunder to the Bank or such other Person with respect to indemnified
liabilities arising from the gross negligence or willful misconduct of the Bank
or such other Person.  10.Miscellaneous.  (a)All terms, conditions, provisions and
covenants in the Agreement and the Collateral Documents and all other documents
delivered to the Bank in connection
therewith shall remain unaltered and in full force and effect except as modified
or amended hereby. To the extent that
any term or provision of this Amendment is or may be deemed expressly
inconsistent with any term or provision in the Agreement or any Collateral
Document or any other document executed in connection therewith, the terms and provisions hereof shall control.  (b)This Amendment constitutes the entire
agreement of the parties with respect to the subject matter hereof and supersedes all prior and
contemporaneous understandings and agreements.  (c)In the event any provisions of this Amendment
shall be held invalid or unenforceable by any court of competent jurisdiction,
such holding shall not invalidate or render unenforceable any other provision hereof.  (d)This Amendment shall be governed by and
construed according to the laws
of the Commonwealth of
Pennsylvania.  (e)This Amendment, and the Agreement and
Collateral Documents as amended hereby, shall inure to the benefit of,
and be binding upon, the parties hereto and thereto and their respective
successors and assigns and may be executed in one or more counterparts, each of
which shall be deemed an original, but all of which together shall constitute one and the same instrument.  (f)The headings used in this Amendment are for
convenience of reference only, do not form a part of this Amendment and shall
not affect in any way the meaning or interpretation of this Amendment.  4


[Signatures to appear on the following page]  5


IN
WITNESS WHEREOF, the parties hereto have executed this Third Amendment to
Reimbursement, Credit and Security Agreement and Waiver as of the day and year
first above written.   INNOVATIVE SOLUTIONS AND
  SUPPORT, LLCBy:
  Innovative Solutions and Support,Incorporated, its sole member andmanagerBy:
  /s/ James ReillyName: James ReillyTitle:   CFOPNC BANK, NATIONAL ASSOCIATIONBy:
  /s/John
  M DiNapoliName:John
  M DiNapoliTitle: Senior Vice President  S-1


CONSENT OF GUARANTORS  Each
of the undersigned guarantors (the Guarantors) consents to the provisions of
the foregoing Third Amendment to Reimbursement, Credit and Security Agreement
and Waiver (the Amendment) and confirms and agrees that: (a) such
Guarantors obligations under its Guaranty dated as of August 1, 2000 (as
the same may be amended, restated or further modified and in effect from time
to time, the Guaranty), relating to the obligations of the Borrower to the
Bank shall be unimpaired by the Amendment; (b) such Guarantor has no
defenses, set offs, counterclaims, discounts or charges of any kind against the
Bank, its officers, directors, employees, agents or attorneys with respect to
the Guaranty; and (c) all of the terms, conditions and covenants in the
Guaranty remain unaltered and in full force and effect and are hereby ratified
and confirmed and apply to the obligations of the Borrower to the Bank,as modified by the Amendment. Each of the Guarantors certifies that all
representations and warranties made by it in the Guaranty are true and correct as of the date of the
Amendment.  Each of the Guarantors ratifies and confirms the
indemnification, confession of judgment and waiver of jury trial provisions, if
any, contained intheGuaranty.  WITNESS
the due execution of this Consent as a document under seal as of the date of
the Amendment, intending to be legally bound hereby of Guarantors.  INNOVATIVE SOLUTIONS ANDSUPPORT, INCORPORATEDBy:
  /s/ James ReillyIS&S DELAWARE, INC.By:
  /s/ James ReillyName: James ReillyTitle:   CFO