<PAGE>
                                                                     EXHIBIT 4.9

                                                                 MCSW:  12/19/01

                                WAIVER AGREEMENT

               WAIVER AGREEMENT, dated as of November 26, 2001, among Mercury
Air Group, Inc., a New York corporation (the "Company"), J. H. Whitney Mezzanine
Fund, L.P., a Delaware limited partnership ("WMF"), and each of the corporations
which are signatories hereto listed as Guarantors (each a "Guarantor"). All
capitalized terms used herein and not otherwise defined herein shall have the
respective meanings provided such terms in the Purchase Agreement referred to
below.

                              W I T N E S S E T H :
                              - - - - - - - - - - -

               WHEREAS, the Company and WMF are parties to a Securities Purchase
Agreement, dated as of September 10, 1999 (as amended, modified or supplemented
through the date hereof, the "Purchase Agreement"); and

               WHEREAS, the Company has requested that WMF provide the waiver
provided for herein, and WMF has agreed to provide such waiver on the terms and
conditions set forth herein;

               WHEREAS, the Guarantors are parties to the Guaranty.

               NOW, THEREFORE, it is agreed:

               1. Pursuant to Section 9.6 of the Purchase Agreement, the Company
has agreed that it will not dispose any of its property, subject to the
exceptions set forth in such section. The Company has advised WMF that it has
sold its land and building located in America's Gateway Park, at 2000 N.W. 89th
Place, Miami, Florida 33172 in violation of such covenant and has requested that
WMF waive compliance by the Company with the covenant set forth in Section 9.6
in connection with such sale. In order to induce WMF to issue such waiver, the
Company represents and warrants that the net proceeds of such sale were used to
pay down the Term Loan and the Revolving Credit under the Senior Credit
Agreement. WMF hereby waives compliance by the Company and its Subsidiaries with
the covenant set forth in Section 9.6 in connection with such sale, subject to
the delivery to WMF of original counterpart signature pages of this Waiver
Agreement, duly executed and delivered by WMF, the Company, and each of the
Guarantors.

               2. For purposes of the Guaranty, by their respective signatures
below, each Guarantor hereby consents and agrees to the entering into of this
Waiver Agreement and acknowledges and affirms that the Guaranty (as amended,
modified or supplemented prior to the date hereof) remains in full force and
effect in accordance with its terms on the date hereof and after giving effect
to this Waiver Agreement.


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               3. This Waiver Agreement is limited as specified and shall not
constitute a modification, acceptance or waiver of any other provision of the
Purchase Agreement or any of the other Transaction Documents.

               4. In order to induce WMF to enter into this Waiver Agreement,
the Company hereby represents and warrants that no default under any of the
Transaction Documents or Event of Default exists or will exist as of the date
hereof.

               5. This Waiver Agreement may be executed in any number of
counterparts and by the different parties hereto on separate counterparts, each
of which counterparts when executed and delivered shall be an original, but all
of which shall together constitute one and the same instrument. A complete set
of counterparts shall be delivered to WMF.

               6. THIS WAIVER AGREEMENT AND THE RIGHTS AND OBLIGATIONS HEREUNDER
SHALL BE GOVERNED BY, CONSTRUED IN ACCORDANCE WITH, AND ENFORCED UNDER, THE LAW
OF THE STATE OF NEW YORK APPLICABLE TO AGREEMENTS OR INSTRUMENTS ENTERED INTO
AND PERFORMED ENTIRELY WITHIN SUCH STATE.

               7. This Waiver Agreement shall become effective when each of the
Company, the Guarantors and WMF shall have signed a counterpart hereof (whether
the same or different counterparts) and shall have delivered (including by way
of telecopier) the same to WMF at its address listed in the Purchase Agreement.

               8. The Company will pay all expenses of WMF (including fees,
charges and disbursements of counsel) in connection with this Waiver Agreement.

               9. From and after the effective date of this Waiver Agreement,
all references in the Purchase Agreement and each of the other Transaction
Documents to the Purchase Agreement shall be deemed to be references to the
Purchase Agreement after giving effect to this Waiver Agreement.

                           [INTENTIONALLY LEFT BLANK]


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               IN WITNESS WHEREOF, each of the parties hereto has caused a
counterpart of this Waiver Agreement to be duly executed and delivered as of the
date first above written.

                                            MERCURY AIR GROUP, INC.
                                            (A NEW YORK CORPORATION)

                                            By:
                                               ---------------------------------
                                            Name:
                                            Title:



                                            J. H. WHITNEY MEZZANINE FUND, L.P.

                                            By: Whitney GP, L.L.C.
                                                Its General Partner

                                            By
                                               ---------------------------------
                                                Name:
                                                A Managing Director

GUARANTORS:

MERCFUEL, INC.

By:
   ---------------------------------
Name:
Title:

MAYTAG AIRCRAFT CORPORATION
By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

MERCURY AIR CARGO, INC.
By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

AEG FINANCE CORPORATION
By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------


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MERCURY AIR CENTERS, INC.
(F/K/A WOFFORD FLYING SERVICES, INC.)

By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

HERMES AVIATION, INC.

By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

VULCAN AVIATION, INC.

By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

RPA AIRLINE AUTOMATION SERVICES, INC.
(F/K/A RENE PEREZ AND ASSOCIATES, INC.)

By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

MERCURY ACCEPTANCE CORPORATION

By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------

EXCEL CARGO, INC.

By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------


                      [SIGNATURE PAGE TO WAIVER AGREEMENT]

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