EXHIBIT 10.3.6



ANALEX CORPORATION



AMENDED AND RESTATED REVOLVING CREDIT FACILITY NOTE



|               |  |                 
|-------------- |  | ----------------
|$20,000,000.00 |  | McLean, Virginia
|               |  | May 28, 2004    



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THIS REVOLVING CREDIT FACILITY NOTE(this Note) is made this 28thday of May, 2004, by the ANALEX CORPORATION, a Delaware corporation, formerly known as Hadron, Inc., for the benefit of BANK OF AMERICA,
N.A., a national banking association (the Lender).



RECITALS



A.    The
Borrower obtained from the Lender, among other things, a revolving credit facility in the current maximum principal sum of $8,000,000 (the Original Credit Facility). The revolving credit facility was evidenced by a
Revolving Credit Facility Note dated August 1, 2002 (the Original Note).



B.    Advances and readvances under the Original Credit Facility have been governed by the terms and conditions of the Credit
Agreement by and between the Borrower and the Lender dated November 2, 2001, as amended from time to time (the Original Financing Agreement). The Original Financing Agreement is being amended and restated pursuant to the
Amended and Restated Credit Agreement of even date herewith (as amended, modified, restated, substituted, extended or renewed at any time and from time to time, the Credit Agreement).



C.    The Borrower has applied to the Lender to increase
the revolving loan portion of the Original Credit Facility to $20,000,000, and to modify certain terms and conditions of the Original Financing Agreement and the Lender has agreed on the condition, among others, that the Original Note be amended and
restated in its entirety and increased.



E.    All defined terms used in this Note and not defined herein shall have the meaning given to such terms in the Credit Agreement.



NOW, THEREFORE, in order to induce the Lender to increase the credit facilities to the Borrower, the Borrower hereby amends
and restates the Original Note as follows:



FOR VALUE
RECEIVED,the undersigned, ANALEX CORPORATION,a Delaware corporation (the Borrower),promises to pay to the order of BANK OF AMERICA, N.A. (the Lender) on or before the
Revolving Credit Facility Maturity Date, and at such earlier dates as may be required by the Agreement (as defined below), the aggregate unpaid principal amount of all Revolving Credit Facility Loans made by the Lender to the Borrower from time to
time pursuant to the Agreement. The Borrower further promises to pay to the order of the Lender interest on the unpaid principal amount hereof from time to time outstanding at the rate or rates per annum determined pursuant to the Agreement, payable
on the dates set forth in the Agreement.



This Note is the
Revolving Credit Facility Note referred to in, and is entitled to the benefits of, the Amended and Restated Credit Agreement, dated as of May 28, 2004 by and among the Borrower, the Subsidiary Guarantors and the Lender (as
the same may be amended, modified or supplemented from time to time, the Agreement), which among other things provides for the acceleration of the maturity hereof upon the occurrence of certain events and for prepayments in
certain circumstances and upon certain terms and conditions. Terms defined in the Agreement have the same meanings herein.



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If the Borrower fails to make any payment under this Note within seven days after the due date, the
Borrower shall pay the Lender a late charge of five percent of the amount of the payment.



This Note is secured by and is entitled to the benefits of the Liens granted by the Security Agreement referred to in the Agreement.



The Borrower hereby expressly waives presentment, demand, protest and all other demands and notices (except as otherwise
provided in the Agreement) in connection with the delivery, acceptance, performance, default or enforcement of this Note and the Agreement, and an action for amounts due hereunder or thereunder shall immediately accrue, in each case except as
otherwise expressly provided in the Agreement.



This Note shall
be governed by, and construed and enforced in accordance with, the laws of the Commonwealth of Virginia, without regard to principles of choice of law.



It is expressly understood and agreed that the indebtedness evidenced by the Original Note has not been extinguished or discharged hereby and is
consolidated herein. The Borrower agrees that the execution of this Note is not intended to and shall not cause or result in a novation with regard to the Original Note or the indebtedness.



ANALEX CORPORATIONBy:

/S/    STERLING E. PHILLIPS, JRName: /S. STERLING E. PHILLIPS, JR. Title: President and CEO




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