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                                                                   EXHIBIT 10.22



                                 PROMISSORY NOTE


$3,500,000                                                      McLean, Virginia
                                                                  April 30, 2001

     FOR VALUE RECEIVED, PEC SOLUTIONS, INC., a corporation organized under the
laws of the State of Delaware (the "Borrower"), promises to pay to the order of
BANK OF AMERICA, N. A., a national banking association (the "Lender"), the
principal sum of THREE MILLION FIVE HUNDRED THOUSAND DOLLARS ($3,500,000) (the
"Principal Sum"), or so much thereof as has been or may be advanced/readvanced
to or for the account of the Borrower pursuant to the terms and conditions of
the Financing Agreement (as hereinafter defined), together with interest thereon
at the rate hereinafter provided, in accordance with the following:

     1.   INTEREST.

     Commencing as of the date hereof and continuing until repayment in full of
all sums due hereunder, the unpaid Principal Sum shall bear interest at the
LIBOR Rate plus two hundred and fifty (250) basis points per annum. For purposes
hereof, the "LIBOR Rate" shall mean a daily fluctuating rate equal to the one
(1) month rate of interest (rounded upwards, if necessary to the nearest 1/100
of 1%) appearing on Telerate Page 3750 (or any successor page) as the one (1)
month London interbank offered rate for deposits in U.S. Dollars at
approximately 11:00 A.M. (London, time), on the second preceding business day,
as adjusted from time to time in the Lender's sole discretion for
then-applicable reserve requirements, deposits insurance assessment rates and
other regulatory costs. If for any reason such rate is not available, the term
"LIBOR Rate" shall mean the fluctuating rate of interest equal to the one (1)
month rate of interest (rounded upwards, if necessary to the nearest 1/100 of
1%) appearing on Reuters Screen LIBO Page as the one (1) month London interbank
offered rate for deposits in U.S. Dollars at approximately 11:00 a.m. (London
Time) on the second preceding business day, as adjusted from time to time for
then-applicable reserve requirements, deposit insurance assessment rates and
other regulatory costs; provided, however, if more than one rate is specified on
Reuters Screen LIBO page, the applicable rate shall be the arithmetic mean of
all such rates.

     The rate of interest charged under this Note shall change immediately and
contemporaneously with any change in the LIBOR Rate. All interest payable under
the terms of this Note shall be calculated on the basis of a 360-day year and
the actual number of days elapsed.

     2.   PAYMENTS AND MATURITY.

     The unpaid Principal Sum, together with interest thereon at the rate
provided above, shall be payable as follows:

          (a) Immediately upon demand made by the Lender subsequent to a draw on
a Letter of Credit (as defined in the Financing Agreement); and

          (b) Unless sooner paid, the unpaid Principal Sum, together with
interest accrued and unpaid thereon, shall be due and payable in full on April
30, 2003.

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     The fact that the balance hereunder may be reduced to zero from time to
time pursuant to the Financing Agreement will not affect the continuing validity
of this Note or the Financing Agreement, and the balance may be increased to the
Principal Sum after any such reduction to zero.

     The Lender is authorized to deduct any payment due hereunder from the
Borrower's account #00000000079225641 issued by the Lender, on or after the date
the payment is due.

     3.   DEFAULT INTEREST.

     Upon the occurrence of an Event of Default (as hereinafter defined), the
unpaid Principal Sum shall bear interest thereafter at a rate three percent (3%)
per annum in excess of the fluctuating prime rate of interest established and
declared by the Lender from time to time until such Event of Default is cured.

     4.   LATE CHARGES.

     If the Borrower shall fail to make any payment under the terms of this Note
within fifteen (15) days after the date such payment is due, the Borrower shall
pay to the Lender on demand a late charge equal to five percent (5%) of such
payment.

     5.   APPLICATION AND PLACE OF PAYMENTS.

     All payments, made on account of this Note shall be applied first to the
payment of any late charge then due hereunder, second to the payment of any
prepayment fee then due hereunder, third to the payment of accrued and unpaid
interest then due hereunder, and the remainder, if any, shall be applied to the
unpaid Principal Sum. All payments on account of this Note shall be paid in
lawful money of the United States of America in immediately available funds
during regular business hours of the Lender at its principal office in McLean,
Virginia or at such other times and places as the Lender may at any time and
from time to time designate in writing to the Borrower.

     6.   FINANCING AGREEMENT AND OTHER FINANCING DOCUMENTS.

     This Note is the "Letter of Credit Note" described in a Financing and
Security Agreement of even date herewith by and between the Borrower and the
Lender (as amended, modified, restated, substituted, extended and renewed at any
time and from time to time, the "Financing Agreement"). The indebtedness
evidenced by this Note is included within the meaning of the term "Obligations"
as defined in the Financing Agreement. The term "Financing Documents" as used in
this Note shall mean collectively this Note, the Financing Agreement and any
other instrument, agreement, or document previously, simultaneously, or
hereafter executed and delivered by the Borrower and/or any other person,
singularly or jointly with any other person, evidencing, securing, guaranteeing,
or in connection with the Principal Sum, this Note and/or the Financing
Agreement.

     7.   SECURITY.

     This Note is secured as provided in the Financing Agreement.


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     8.   EVENTS OF DEFAULT.

     The occurrence of any one or more of the following events shall constitute
an event of default (individually, an "Event of Default" and collectively, the
"Events of Default") under the terms of this Note:

          (a) The failure of the Borrower to pay to the Lender when due any and
all amounts payable by the Borrower to the Lender under the terms of this Note;
or

          (b) The occurrence of an event of default (as defined therein) under
the terms and conditions of any of the other Financing Documents.

     9.   REMEDIES.

     Upon the occurrence of an Event of Default, at the option of the Lender,
all amounts payable by the Borrower to the Lender under the terms of this Note
shall immediately become due and payable by the Borrower to the Lender without
notice to the Borrower or any other person, and the Lender shall have all of the
rights, powers, and remedies available under the terms of this Note, any of the
other Financing Documents and all applicable laws. The Borrower and all
endorsers, guarantors, and other parties who may now or in the future be
primarily or secondarily liable for the payment of the indebtedness evidenced by
this Note hereby severally waive presentment, protest and demand, notice of
protest, notice of demand and of dishonor and non-payment of this Note and
expressly agree that this Note or any payment hereunder may be extended from
time to time without in any way affecting the liability of the Borrower,
guarantors and endorsers.

     10.  ARBITRATION AND WAIVER OF JURY TRIAL.

          (a) This paragraph concerns the resolution of any controversies or
claims between the Borrower and the Lender, whether arising in contract, tort or
by statute, including but not limited to controversies or claims that arise out
of or relate to: (i) this Note (including any renewals, extensions or
modifications); or (ii) any document related to this Note; (collectively a
"Claim").

          (b) At the request of the Borrower or the Lender, any Claim shall be
resolved by binding arbitration in accordance with the Federal Arbitration Act
(Title 9, U. S. Code) (the "Act"). The Act will apply even though this Note
provides that it is governed by the law of a specified state.

          (c) Arbitration proceedings will be determined in accordance with the
Act, the rules and procedures for the arbitration of financial services disputes
of J.A.M.S./Endispute or any successor thereof ("J.A.M.S."), and the terms of
this paragraph. In the event of any inconsistency, the terms of this paragraph
shall control.

          (d) The arbitration shall be administered by J.A.M.S. and conducted in
any U. S. state where real or tangible personal property collateral for this
credit is located or if there is no such collateral, in the Commonwealth of
Virginia. All Claims shall be determined by one arbitrator; however, if Claims
exceed $5,000,000, upon the request of any party, the Claims shall


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be decided by three arbitrators. All arbitration hearings shall commence within
90 days of the demand for arbitration and close within 90 days of commencement
and the award of the arbitrator(s) shall be issued within 30 days of the close
of the hearing. However, the arbitrator(s), upon a showing of good cause, may
extend the commencement of the hearing for up to an additional 60 days. The
arbitrator(s) shall provide a concise written statement of reasons for the
award. The arbitration award may be submitted to any court having jurisdiction
to be confirmed and enforced.

          (e) The arbitrator(s) will have the authority to decide whether any
Claim is barred by the statute of limitations and, if so, to dismiss the
arbitration on that basis. For purposes of the application of the statute of
limitations, the service on J.A.M.S. under applicable J.A.M.S. rules of a notice
of Claim is the equivalent of the filing of a lawsuit. Any dispute concerning
this arbitration provision or whether a Claim is arbitrable shall be determined
by the arbitrator(s). The arbitrator(s) shall have the power to award legal fees
pursuant to the terms of this Note.

          (f) This paragraph does not limit the right of the Borrower or the
Lender to: (i) exercise self-help remedies, such as but not limited to, setoff;
(ii) initiate judicial or non-judicial foreclosure against any real or personal
property collateral; (iii) exercise any judicial or power of sale rights, or
(iv) act in a court of law to obtain an interim remedy, such as but not limited
to, injunctive relief, writ of possession or appointment of a receiver, or
additional or supplementary remedies.

          (g) By agreeing to binding arbitration, the parties irrevocably and
voluntarily waive any right they may have to a trial by jury in respect of any
Claim. Furthermore, without intending in any way to limit this Note to
arbitrate, to the extent any Claim is not arbitrated, the parties irrevocably
and voluntarily waive any right they may have to a trial by jury in respect of
such Claim. This provision is a material inducement for the parties entering
into this Note.

     11.  EXPENSES.

     The Borrower promises to pay to the Lender on demand by the Lender all
costs and expenses incurred by the Lender in connection with the collection and
enforcement of this Note, including, without limitation, reasonable attorneys'
fees and expenses and all court costs.

     12.  NOTICES.

     Any notice, request, or demand to or upon the Borrower or the Lender shall
be deemed to have been properly given or made when delivered in accordance with
Section 8.1 of the Financing Agreement.

     13.  MISCELLANEOUS.

     Each right, power, and remedy of the Lender as provided for in this Note or
any of the other Financing Documents, or now or hereafter existing under any
applicable law or otherwise shall be cumulative and concurrent and shall be in
addition to every other right, power, or remedy provided for in this Note or any
of the other Financing Documents or now or hereafter existing under any
applicable law, and the exercise or beginning of the exercise by the Lender of


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any one or more of such rights, powers, or remedies shall not preclude the
simultaneous or later exercise by the Lender of any or all such other rights,
powers, or remedies. No failure or delay by the Lender to insist upon the strict
performance of any term, condition, covenant, or agreement of this Note or any
of the other Financing Documents, or to exercise any right, power, or remedy
consequent upon a breach thereof, shall constitute a waiver of any such term,
condition, covenant, or agreement or of any such breach, or preclude the Lender
from exercising any such right, power, or remedy at a later time or times. By
accepting payment after the due date of any amount payable under the terms of
this Note, the Lender shall not be deemed to waive the right either to require
prompt payment when due of all other amounts payable under the terms of this
Note or to declare an Event of Default for the failure to effect such prompt
payment of any such other amount. No course of dealing or conduct shall be
effective to amend, modify, waive, release, or change any provisions of this
Note.

     14.  PARTIAL INVALIDITY.

         In the event any provision of this Note (or any part of any provision)
is held by a court of competent jurisdiction to be invalid, illegal, or
unenforceable in any respect, such invalidity, illegality, or unenforceability
shall not affect any other provision (or remaining part of the affected
provision) of this Note; but this Note shall be construed as if such invalid,
illegal, or unenforceable provision (or part thereof) had not been contained in
this Note, but only to the extent it is invalid, illegal, or unenforceable.

     15.  CAPTIONS.

     The captions herein set forth are for convenience only and shall not be
deemed to define, limit, or describe the scope or intent of this Note.

     16.  APPLICABLE LAW.

     The Borrower acknowledges and agrees that this Note shall be governed by
the laws of the Commonwealth of Virginia, even though for the convenience and at
the request of the Borrower, this Note may be executed elsewhere.

     17.  CONSENT TO JURISDICTION.

     The Borrower irrevocably submits to the jurisdiction of any state or
federal court sitting in the Commonwealth of Virginia over any suit, action, or
proceeding arising out of or relating to this Note or any of the other Financing
Documents. The Borrower irrevocably waives, to the fullest extent permitted by
law, any objection that the Borrower may now or hereafter have to the laying of
venue of any such suit, action, or proceeding brought in any such court and any
claim that any such suit, action, or proceeding brought in any such court has
been brought in an inconvenient forum. Final judgment in any such suit, action,
or proceeding brought in any such court shall be conclusive and binding upon the
Borrower and may be enforced in any court in which the Borrower is subject to
jurisdiction by a suit upon such judgment, provided that service of process is
effected upon the Borrower as provided in this Note or as otherwise permitted by
applicable law.


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     18.  SERVICE OF PROCESS.

     The Borrower hereby consents to process being served in any suit, action,
or proceeding instituted in connection with this Note by (a) the mailing of a
copy thereof by certified mail, postage prepaid, return receipt requested, to
the Borrower and (b) serving a copy thereof upon Commonwealth Legal Services
Corporation, 4701 Cox Road, Suite 301, Glen Allen, VA 23060-6802, the agent
hereby designated and appointed by the Borrower as the Borrower's agent for
service of process. The Borrower irrevocably agrees that such service shall be
deemed in every respect effective service of process upon the Borrower in any
such suit, action or proceeding, and shall, to the fullest extent permitted by
law, be taken and held to be valid personal service upon the Borrower. Nothing
in this Section shall affect the right of the Lender to serve process in any
manner otherwise permitted by law or limit the right of the Lender otherwise to
bring proceedings against the Borrower in the courts of any jurisdiction or
jurisdictions.

     19.  WAIVER OF TRIAL BY JURY.

     THE BORROWER AND THE LENDER HEREBY WAIVE TRIAL BY JURY IN ANY ACTION OR
PROCEEDING TO WHICH THE BORROWER AND THE LENDER MAY BE PARTIES, ARISING OUT OF
OR IN ANY WAY PERTAINING TO (A) THIS NOTE OR (B) THE FINANCING DOCUMENTS. IT IS
AGREED AND UNDERSTOOD THAT THIS WAIVER CONSTITUTES A WAIVER OF TRIAL BY JURY OF
ALL CLAIMS AGAINST ALL PARTIES TO SUCH ACTIONS OR PROCEEDINGS, INCLUDING CLAIMS
AGAINST PARTIES WHO ARE NOT PARTIES TO THIS NOTE.

     THIS WAIVER IS KNOWINGLY, WILLINGLY AND VOLUNTARILY MADE BY THE BORROWER,
AND THE BORROWER HEREBY REPRESENTS THAT NO REPRESENTATIONS OF FACT OR OPINION
HAVE BEEN MADE BY ANY INDIVIDUAL TO INDUCE THIS WAIVER OF TRIAL BY JURY OR TO IN
ANY WAY MODIFY OR NULLIFY ITS EFFECT. THE BORROWER FURTHER REPRESENTS THAT IT
HAS BEEN REPRESENTED IN THE SIGNING OF THIS NOTE AND IN THE MAKING OF THIS
WAIVER BY INDEPENDENT LEGAL COUNSEL, SELECTED OF ITS OWN FREE WILL, AND THAT IT
HAS HAD THE OPPORTUNITY TO DISCUSS THIS WAIVER WITH COUNSEL.

     IN WITNESS WHEREOF, the Borrower has caused this Note to be executed under
seal by its duly authorized officers as of the date first written above.


WITNESS OR ATTEST:                         PEC SOLUTIONS, INC.



______________________________             By:__________________________(SEAL)
                                              Name:
                                              Title:




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