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        M a y  7 ,  2 0 0 9
 John C. Long Chief Financial Officer Innovative Solutions and Support, Inc. 720 Pennsylvania Drive Exton, PA 19341
Re: Innovative Solutions and Support, Inc.
Form 10-K and Form 10-K/A fo r the Fiscal Year Ended
September 30, 2008  Filed December 11, 2008 and December 19, 2008
  Form 10-Q for the Fiscal Quarter Ended December 31, 2008
  Filed on February 6, 2009
File No. 000-31157

Dear Mr. Long:

We have reviewed your response letter  dated April 22, 2009 in connection with
the above-referenced filings and have the fo llowing comments.  If indicated, we think
you should revise your document in response to these comments.  If you disagree, we
will consider your explanation as to why our comment is inapplicable or a revision is
unnecessary.  Please be as deta iled as necessary in your expl anation.  In some of our
comments, we may ask you to provide us w ith supplemental information so we may
better understand your disclosure.  After re viewing this information, we may raise
additional comments.  Unless otherwise noted, where prior comments are referred to they
refer to our letter dated April 10, 2009.

Form 10-K and Form 10-K/A for Fi scal Year Ended September 30, 2008

General
1. We note from your response to our prior comment 1 that you concluded the errors
in the presentation of the line items on th e cash flow statement did not meet the
definition of an error under SFAS 154 becau se they resulted from a typographical
error and not a mathematical mistake.  The Staff believes that the error in the
presentation and disclosures of the cash flow statement resulted from an oversight
(i.e. an inadvertent omission or an unintentional mistake) of facts that existed at

John C. Long
Innovative Solutions and Support, Inc. May 7, 2009 Page 2
the time the financial statements were prepared and therefor e, would meet the
definition of an error pursuant to para graph 2(h) of SFAS 154.  Accordingly,
please file an Item 4.02 Form 8-K.
2. In addition, we note from your disclosu res on page 52 of the September 30, 2008
Form 10-K that the Company performed an evaluation of the effectiveness of your disclosure controls and pr ocedures as of September 30, 2007
.  Please
confirm that the Company performed your evaluation as of th e end of the period
covered by the report (i.e. September 30, 2008) .  Further, considering the error in
the cash flow statement and the failure to file an Item 4.02 Form 8-K, please tell us whether your officers have reconsider ed the effectiveness of your disclosure
controls and procedures for the periods im pacted.  Also, please confirm to us that
you plan to address this rec onsideration and the related conclusions in your Form
10-Q for the quarter ended March 31, 2009.

* * * * * * *

Please respond to these comments within  10 business days or tell us when you
will provide us with a response.  Please  submit all correspondence and supplemental
materials on EDGAR as required by Rule 101 of Regulation S-T.  If you amend your
filing(s), you may wish to provide us with marked copies of any amendment to expedite our review.  Please furnish a cover letter that keys your response to our comments and
provides any requested information.  Detailed co ver letters greatly faci litate our review.
Please understand that we may have addi tional comments after reviewing any
amendment and your response to our comments.

You may contact Melissa Fe ider, Staff Accountant, at  (202) 551-3379 or me at
(202) 551-3499 if you have any questions regarding comments on the financial statements and related matters.  Please addre ss questions regarding all other comments to
Kevin Dougherty, Staff Attorne y, at (202) 551-3271 or Mark P. Shuman, Legal Branch
Chief, at (202) 551-3457.
       S i n c e r e l y ,           Kathleen Collins
Accounting Branch Chief