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                                                                   EXHIBIT 10.10

                                    STANDARD
                                  OFFICE LEASE

PROPERTY: TYCON TOWER I BUILDING

LANDLORD: TYCON TOWER I INVESTMENT LIMITED PARTNERSHIP

TENANT:   ALLIED RESEARCH CORPORATION

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                                  LEASE BETWEEN

                  TYCON TOWER I INVESTMENT LIMITED PARTNERSHIP

                                       AND

                           ALLIED RESEARCH CORPORATION

                                TABLE OF CONTENTS

SECTION                                  TITLE                             PAGE
-------      ------------------------------------------------------------  ----

  1          Premises....................................................    6
  2          Term........................................................    6
  3          Rent........................................................    7
  4          Operating Expenses and Real Estate Taxes....................    7
  5          Preparation of Premises for Tenant's Occupancy..............    9
  6          Delayed Possession..........................................    9
  7          Use of Premises.............................................   10
  8          Assignment and Subletting...................................   11
  9          Maintenance by Tenant.......................................   12
  10         Hours of Operation and Service..............................   12
  11         Tenant Alterations; Installation of Fixtures................   13
  12         Advertising.................................................   14
  13         Inspections; Entry..........................................   15
  14         Insurance...................................................   15
  15         Damage to Premises..........................................   16
  16         Liability of Landlord.......................................   17
  17         Casualty....................................................   18
  18         Condemnation................................................   18
  19         Default.....................................................   19
  20         Subordination...............................................   23
  21         Jury Trial..................................................   24
  22         Holdover....................................................   24
  23         Successors' Obligation......................................   24
  24         Rules and Regulations.......................................   25
  25         Covenants of Landlord.......................................   25
  26         Reservation of Rights of Landlord...........................   25
  27         Security Deposit............................................   25
  28         Parking.....................................................   26
  29         Mortgagee Approval..........................................   26
  30         Gender......................................................   26
  31         Notices.....................................................   26
  32         Estoppel Certificates.......................................   27
  33         Governing Law...............................................   28
  34         Commissions.................................................   28

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  35         Waiver of Breach............................................   28
  36         Severability of Clauses.....................................   28
  37         Captions for Convenience....................................   28
  38         Duplicate Counterparts Originals............................   28
  39         Recordation.................................................   29
  40         Effectiveness...............................................   29
  41         Right to Relocate...........................................   29
  42         No Partnership..............................................   29
  43         Time of Essence.............................................   29
  44         Force Majeure...............................................   29
  45         Entire Agreement............................................   29
  46         Hazardous Wastes............................................   29
  47         Joint and Several Liability.................................   30
  48         Corporate Tenants' Fictitious Names.........................   30
  49         Conflicts...................................................   30

                                    EXHIBITS

Exhibit A    Floor Plan of the Premises
Exhibit B    Form of Lease Commencement Addendum
Exhibit C    Rules and Regulations of the Building
Exhibit D    Agreement of Leasehold Improvements
Exhibit E    Parking Agreement
Exhibit F    Non-Disturbance, Attornment and Subordination Agreement

Lease Addendum

                                        2

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                               GENERAL INFORMATION

1.   Premises Telephone Number: ________________________________________________

2.   Names and Addresses: ______________________________________________________
     ___________________________________________________________________________
     ___________________________________________________________________________
     ___________________________________________________________________________
     ___________________________________________________________________________

     (a)  Address for Notices and Billing:

          Name:            _____________________________________________________
          Address:         _____________________________________________________
          ______________________________________________________________________
          ______________________________________________________________________

          Home Telephone Number:    ____________________________________________
          Office Telephone Number:  ____________________________________________

     (b)  Tenant, or if Corporation or Partnership, principal officer of
          partner:

          Name:            _____________________________________________________
          Address:         _____________________________________________________
          ______________________________________________________________________
          ______________________________________________________________________

     (c)  Person to call in case of emergency:

          Name:            _____________________________________________________
          Address:         _____________________________________________________
          ______________________________________________________________________
          ______________________________________________________________________

     (d)  Guarantor:

          Name:            _____________________________________________________
          Address:         _____________________________________________________
          ______________________________________________________________________
          ______________________________________________________________________

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     (e)  Registered Agent, if Tenant is a Corporation:

          Name:            _____________________________________________________
          Address:         _____________________________________________________
          ______________________________________________________________________
          ______________________________________________________________________

     (f)  Accountant for Tenant:

          Name:            _____________________________________________________
          Address:         _____________________________________________________
          ______________________________________________________________________
          ______________________________________________________________________

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                                  OFFICE LEASE

     THIS AGREEMENT OF LEASE (the "Lease") made this _______ day of ___________,
1993, by and between TYCON TOWER I INVESTMENT LIMITED PARTNERSHIP, a Virginia
limited partnership ("Landlord") and ALLIED RESEARCH CORPORATION, a corporation
authorized to do business in the Commonwealth of Virginia ("Tenant").

     WITNESSETH, that for and in consideration of the rent hereinafter reserved
and of the mutual covenants and agreements hereinafter set forth, Landlord and
Tenant mutually agree as follows:

                                   DEFINITIONS

     For purposes of this Lease, the Exhibits attached and made a part hereof
and all agreements supplemental to this Lease, the following terms shall have
the respective meanings as set forth in the following Section, subsection,
paragraph and Exhibit references:

                                                                      Reference
Alterations...................................................           11 (a)
Base Rent.....................................................            3 (a)
Base Year.....................................................            4 (a)
Building......................................................                1
Certificate of Deposit........................................         Addendum
Estoppel Certificate..........................................            6 (d)
Event of Default..............................................           19 (d)
Hazardous Materials...........................................               46
Improvement Allowance.........................................         Addendum
Land..........................................................                1
Lease Commencement Date.......................................            2 (c)
Lease Expiration Date.........................................            2 (a)
Leasehold Improvements........................................                5
Letter of Credit..............................................         Addendum
Monthly Base Rent.............................................            3 (a)
Mortgages.....................................................            20 (a)
Operating Expenses............................................             4 (a)
Parking Facilities............................................            Ex. E
Plan..........................................................                5
Premises......................................................                1
Property......................................................                1
Proportionate Share...........................................            4 (d)
Relocation Allowance..........................................         Addendum
Renewal Term..................................................         Addendum
Rules and Regulations.........................................            Ex. C
Security Deposit..............................................               27
Square Footage Calculations...................................            4 (f)
Temporary Space...............................................         Addendum
Term..........................................................            2 (a)
Transfer......................................................            8 (a)

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     1.   PREMISES. Landlord leases to Tenant, and Tenant leases from Landlord,
for the Term (as hereinafter defined) and upon the covenants and conditions
hereinafter set forth, the space (the "Premises") described as follows: Suite
750, consisting of approximately 4,341 square feet, as shown on a floor plan
attached hereto and incorporated herein by reference as Exhibit A, on the 7th
floor in the office building located at 8000 Towers Crescent Drive, Vienna,
Virginia, known as the Tycon Tower I Building (the "Building") located on a
subdivided parcel of Land (the "Land"). The Premises, the Building, the Land,
and the adjacent parking facilities are hereinafter sometimes referred to
collectively as the "Property". Any premises situation on the ground floor of
the Building do not include the basement space below such premises and any
premises situated on the top floor of the Building do not include the roof of
the Building.

     2.   TERM.

          (a)  Duration. The Term of this Lease (the "Term") shall be three (3)
years. The Term shall commence on the Lease Commencement Date (as hereinafter
defined) and shall terminate at 12:00 Midnight on the last day of the
thirty-sixth (36th) full calendar month following the Lease Commencement Date
(the "Lease Expiration Date") or on such earlier date when said Term may be
terminated pursuant to any of the conditions or covenants of this Lease or
pursuant to law.

          (b)  Partial Month Occupancy. If the Lease Commencement Date occurs on
a date other than the first day of a calendar month, the Term shall commence on
such date and shall continue for the balance of such month and for a period of
three (3) years thereafter. In such event, rent shall be pro-rated for such
fractional period of any partial month Tenant occupies the Premises.

          (c)  Lease Commencement Date. The term "Lease Commencement Date" means
the later of (i) June 1, 1993 or (ii) the date Landlord's representative
certifies that the Premises are substantially completed. The Premises shall be
deemed substantially completed when all the Leasehold Improvements (See, Exhibit
D attached hereto) Landlord is to provide pursuant to the terms of this Lease
have been constructed, except for minor items of work and adjustment or
equipment and fixtures which can be completed after Tenant has occupied the
Premises without causing substantial interference with Tenant's use of the
Premises (i.e., so called "punch list" items).

          (d)  Early Possession. If the Premises are substantially completed
before June 1, 1993 Tenant may move into the Premises at that time and shall be
subject to all the terms and conditions of this Lease except that Tenant shall
not be required to pay rent until June 1, 1993 and the Lease Commencement Date
would be June 1, 1993.

          (e)  Rule Against Perpetuities. If the rule against perpetuities would
invalidate this Lease or any portion hereof, or would limit the time during
which this Lease shall be effective, due to the potential failure of an interest
in property created herein to vest within a particular time, then
notwithstanding anything to the contrary herein, each such interest in property
must vest, if at all, before the passing of twenty-one (21) years from the date
of this

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Lease, or this Lease shall become null and void upon the expiration of such
twenty-one (21) year period and the parties shall have no further liability
hereunder.

     3.   RENT.

          (a)  Base Rent. During and for the Term hereof, commencing on the date
Landlord tenders possession of the Premises to Tenant, Tenant shall pay to
Landlord for the Premises, without notice of deemed and without deduction,
setoff or abatement, a minimum guaranteed annual base rent ("Base Rent") of the
sum of Nineteen and 50/100 Dollars ($19.50) per square foot of rentable area
contained in the Premises or Eighty-Four Thousand Six Hundred Forty-Nine and
50/100 Dollars ($84,649.50), payable in equal monthly installments ("Monthly
Base Rent") in advance and subject to adjustment as set forth in subsection (b)
of this Section 3. Tenant shall pay all rent to landlord at Landlord's office,
or to such other party or at such other address as Landlord may designate from
time to time by written notice to Tenant. Tenant shall pay the rent on the first
day of each and every calendar month during the Term hereof, provided, however,
that the Monthly Base Rent for the first month of the Term shall be due and
payable at the time Tenant executes this Lease.

          (b)  Rental Increase. The Monthly Base Rent shall be increased on the
anniversary of the Lease Commencement Date of each year during the Term hereof,
beginning in 1994, by three percent (3%) of the Monthly Base Rent for the month
immediately proceeding.

          (c)  Late Fees. Tenant shall pay to Landlord a late fee equal to three
percent (3%) of the Monthly Base Rent if Landlord does not receive any such
payment within seven (7) days of its due date. In addition, any such delinquent
payment shall bear interest at the rate of eighteen percent (18%) per annum,
provided, however, that nothing herein contained shall be construed or
implemented in such a manner as to allow Landlord to charge or receive interest
in excess of the maximum rate then allowed by law. All such late fees and
interest charges shall be deemed additional rent due hereunder and shall be
payable with the next installment of Monthly Base Rant.

          (d)  Square Footage Calculations. For the purposes of this Section 3,
the number of square feet of rentable area contained the Premises is hereby
deemed the equivalent of 4,341 square feet (including a factor for common areas
contained in the Building). Said square footage has been calculated in
accordance with the WDCAR Standard Method of Measurement (Revised 1989).

     4.   OPERATING EXPENSES AND REAL ESTATE TAXES.

          (a)  Payments. During and for the Term hereof, Tenant shall pay, as
additional rent, for its proportionate share any operating expenses and real
estate taxes for the Property, including real estate taxes and operating
expenses for the Land which may be paid as part of the ground rent, if any
(operating expenses and real estate taxes are hereinafter referred to
collectively as "Operating Expenses"), in excess of the total Operating Expenses
for the Property for the calendar year 1993 (hereinafter referred to as the
"Base Year"). Tenant shall pay the increases in Operating Expenses as follows:

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               (i)     Commencing on the first day of the thirteen (13th) month
following the Lease Commencement Date, and at the beginning of each Calendar
Year thereafter, Tenant shall pay to landlord, on the first day of each calendar
month, an amount equal to one-twelfth (1/12) of Tenant's proportionate share of
Landlord's reasonable estimate (as adjusted annually) of the amount that the
Operating Expenses for the then current calendar year exceeds the actual amount
of such costs for the Base Year. Landlord's reasonable estimate of such increase
for any calendar year shall not exceed fifteen percent (15%) of the Operating
Expenses for the immediately preceding calendar year.

               (ii)    Within one-hundred twenty (120) days following the end of
each calendar year, including the initial calendar year of the Lease, or as
promptly thereafter as is reasonably feasible, Landlord shall furnish to Tenant
a statement covering such year, certified as correct by an authorized
representative of Landlord, showing the total Operating Expenses, the amount of
Tenant's proportionate share of the same, and the payments Tenant made during
such year. Subject to the provisions of Section 4(a)(i) above, if Tenant's
proportionate share of Operating Expenses exceeds Tenant's payments so made,
Tenant shall pay Landlord the deficiency within thirty (30) days after Tenant's
receipt of such statement. If Tenant's payments exceed Tenant's proportionate
share, Tenant may offset the excess against payments next due Landlord
hereunder, or, if this Lease has expired and Tenant has returned the Premises to
Landlord and has made all payments called for in this Lease, Landlord shall
refund the excess to Tenant.

          (b)  Included in Operating Expenses. The term "Operating Expenses" as
used in this Lease means all expenses, costs, and disbursements of every kind
and nature which Landlord pays or becomes obligated to pay in connection with
the service, ownership and/or operation, maintenance and repair of the Property.
By way of example, but without limitation, Operating Expenses include wages,
salaries, bonuses, fringe benefits (including insurance and pension payments)
and uniforms (including cleaning costs) for all employees engaged in the
operation, maintenance or repair of the Property; social security, unemployment
and other payroll taxes; license fees; worker's compensation insurance;
electricity (except as may be directly billed to tenants of the Building), gas,
water, sewer and other fuel and utilities; utility taxes; fire, casualty,
liability, plate glass, and other insurance; repairs, security, maintenance,
painting, and cleaning of the Property and supplies necessary therefore;
cleaning of windows and exterior curtain walls, snow removal, and other service
contracts as are reasonably required to operate the Building as a first-class
office building; general overhead, administrative expenses and management fees
(including an amount equal to the fair market value of any on-site manager's
office); legal, accounting, and other professional fees and disbursements
incurred in operating and managing the Property; decorations; maintenance of
exterior and interior landscaping; general and special real estate or ad valorem
taxes or special assessments levied against the Property by any governmental or
quasi-governmental authority, or any taxes or assessments which may be levied on
the Property in lieu of or in addition to such taxes, or levied on the rentals
from the Property, or levied on Landlord as a result of the use, ownership or
operation of the Property; and any other costs, charges and expenses which,
under generally accepted accounting and management principles, are regarded as
maintenance and operating expenses.

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          (c)  Excluded from Operating Expenses. Operating Expenses do not
include any of the following: expenses for capital improvements made to the
Property except those expenses (which shall be amortized on a straight-line
bases over the useful life of each such item) which are incurred in order to
decrease the overall operating expenses for the Property or are incurred for the
general operation or maintenance of the Property; expenses for painting,
redecorating, or other work which Landlord performs for any tenant of the
Building; interest, amortization, or other payments on loans to Landlord, or any
costs connected with refinancing of such loans; charges for depreciation of the
Building or other improvements; ground rent payments; real estate brokerage fees
and commissions; advertising and marketing costs; Landlord's income taxes; and
any Operating Expenses which are paid by any tenant directly to the provider of
the service or for which is reimbursed directly by a tenant.

          (d)  Proportionate Share. The term "proportionate share" as used in
this Lease means that fraction having as a numerator the number of square feet
of rentable area contained in the Premises, and as a denominator 416,754 square
feet. Tenant's proportionate share figure are subject to adjustment throughout
the Term as the figures used in the calculation change due to expansion or
reduction of the Premises or change in layout of the Building.

          (e)  Adjustment for Partial Occupancy. If less than 95% of the
rentable area contained in the Building is occupied during any year, adjustments
shall be made in computing Operating Expenses so that the Operating Expenses for
such year will be computed as though 95% of the rentable area in the Building
were so occupied.

          (f)  Square Footage Calculations. For the purposes of this Section 4,
the number of square feet of rentable area contained in the Premises is hereby
deemed the equivalent of 4,341 square feet (including a factor for common areas
contained in the Building). Said square footage has been calculated in
accordance with WDCAR Standard Method of Measurement (Revised 1989).

          (g)  Audit. Upon the prior written request of Tenant and not more than
once per calendar year, Landlord shall provide Tenant or Tenant's representative
access to all back-up data utilized by Landlord in the calculation of Operating
Expenses. Any review by Tenant or Tenant's representative of such back-up data
shall occur during normal business hours.

     5.   PREPARATION OF PREMISES FOR TENANT'S OCCUPANCY. Landlord shall
construct, as its sole costs and expense, the improvements to the Premises
described in _____________________ dated ___________, prepared by Bert Primo
Associates (the "Plan") in accordance with the provisions of Exhibit D attached
hereto and incorporated herein by reference (the "Leasehold Improvements"). Any
other improvements Tenant requires to the Premises shall be made at Tenant's
sole cost and expense.

     6.   DELAYED POSSESSION.

          (a)  Effect on Obligation to Pay Rent. Landlord shall tender
possession of the Premises to Tenant on or about June 1, 1993. If Landlord fails
to tender possession by June 1,

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1993 because of Tenant's fault, including but not limited to Tenant's failure to
comply with the requirements set forth in Exhibit D herein, any delay in
tendering possession to Tenant which is caused thereby shall be Tenant's
responsibility, the Lease Commencement Date shall be determined, and Tenant
shall commence paying rent for the Premises on the date substantial completion
of the Premises would have occurred but for the delay caused by Tenant. If
Landlord fails to tender possession to Tenant by June 1, 1993 due to any reason
other than Tenant's fault, the Lease Commencement Date shall be postponed until
the date when Landlord tenders possession of substantially completed Premises to
Tenant and any rents payable hereunder shall be abated until said date. Any
delay due to any reason other than Tenant's fault shall be deducted on a day for
day basis from the amount of delay Tenant causes by failing to comply with the
time requirements of this subsection (a) of Section 6.

          (b)  No Landlord Liability. If Landlord fails to tender possession of
the Premises to Tenant by June 1, 1993 for any reason, such failure to do so
shall not affect or impair the validity of the Lease for the Premises or
Tenant's obligations hereunder, except as expressly provided in subsection (c)
below, and Landlord shall not be liable for damages for such failure to give
possession on said date.

          (c)  Termination Rights. If for any reason Landlord fails to tender
possession of the Premises to Tenant by August 1, 1993, and provided that the
delay is not due to Tenant's fault, then Tenant shall have as its sole remedy,
with no further liability or obligation on the part of either party, the right
to terminate this Lease after such date by giving thirty (30) days prior written
notice of such termination to Landlord. If Landlord tenders possession of the
Premises to Tenant after Tenant has given such notice but before the expiration
of such thirty (30) day period, any notice given by Tenant shall thereupon be
nullified. Upon any such cancellation becoming effective, Landlord and Tenant
shall be entirely relieved of their obligation hereunder, and any security
deposit and prepaid rent given by Tenant to Landlord shall be returned to
Tenant. Any delay which is due to any reason other than the fault of Landlord,
its contractor or subcontractor, shall be deducted on a day for day basis from
the amount of delay caused by Landlord in compliance with the time requirements
of this subsection (c) of Section 6.

          (d)  Estoppel Certificate. Promptly after Landlord tenders possession
of the Premises to Tenant, Landlord and Tenant shall execute an Estoppel.
Certificate in the form attached hereto as Exhibit B, which certificate shall
set forth the actual Lease Commencement Date.

     7.   USE OF PREMISES. Tenant shall continuously throughout the Term use and
occupy the Premises solely for general office use consistent with the character
of a first-class office building in the Washington, D.C. Metropolitan area.
Tenant shall not use the Premises or any other portion of the Property for any
unlawful purpose. Tenant, at Tenant's expense, shall comply with all present and
future laws, ordinances, regulations, and orders of the United States of
America, Commonwealth of Virginia, County of Fairfax, and any other public or
quasi-public authority having jurisdiction over the Premises, including, without
limitation, all applicable federal, state and local laws, regulations or
ordinances pertaining to air and water quality, and Hazardous Materials (as
hereinafter defined), waste disposal, air emissions and other environmental
matters, all zoning and other land use matters, and utility availability.

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     8.   ASSIGNMENT AND SUBLETTING.

          (a)  Restricting on Assignment and Subletting. Tenant acknowledges
that Landlord has entered into this Lease because of Tenant's financial
strength, goodwill, ability and expertise and that, accordingly, this Lease is
personal to Tenant. Tenant agrees for itself and for its successors and assigns
in interest hereunder that it shall not assign, transfer, mortgage, or otherwise
encumber all or any part of this Lease, or sublet, rent, or permit occupancy or
use of all or any part of the Premises (each of which is referred to for
purposes of this Section as a "Transfer"), without obtaining Landlord's prior
written consent, which consent shall not be unreasonably withheld. In addition,
no Transfer of this Lease or the right of occupancy hereunder may be affected by
operation of law, including, but not limited to, sale of a majority of
outstanding stock in Tenant or a majority partnership interest in Tenant, as the
case may be, or in any manner other than with Landlord's prior written consent,
which consent shall not be unreasonably withheld. Any consent granted shall not
be construed to relieve Tenant from the obligation to obtain Landlord's written
consent to any further Transfer. If Landlord consents to a Transfer and accepts
the payment of rent or the performance and observance of any of the terms and
conditions of this Lease from any Transferee such acceptance shall not be
construed as waiving or releasing Tenant from liability hereunder to pay rent or
to perform and observe any of the terms and conditions of this Lease. Any person
to whom any Transfer is attempted without Landlord's consent shall have no
claim, right or remedy whatsoever against Landlord, and Landlord shall have no
duty to recognize any person or entity claiming under or through the same.

          (b)  Notice Requirements. If Tenant desires to assign or sublet all or
a portion of the Premises, Tenant shall request, in writing, at least thirty
(30) days before the intended effective date of the proposed assignment or
subletting, Landlord's consent, which request shall include the name, address
and a current financial statement of the proposed subtenant or assignee, and a
copy of the proposed assignment or sublease, specifying, among other items, the
proposed use, the Term and the rent. In such event, landlord shall have the
option to (i) sublet such portion of the Premises from Tenant for the Term of
the proposed assignment or sublease at the Monthly Base Rent set forth herein,
or (ii) terminate this Lease for the affected portion of the Premises, as of the
effective date of the proposed sublease or assignment. Within thirty (30) days
after receipt of said notice, together with all of the required information,
Landlord shall give written notice to Tenant, stating whether Landlord approves
or disapproves the proposed assignment or sublease, or whether Landlord shall
exercise its option to sublet or terminate as set forth above.

          (c)  Tenant Default. If Tenant defaults hereunder, after any
applicable cure period, Tenant hereby assigns to Landlord the rent due from
Tenant's Transferee and authorizes each such Transferee to pay said rent
directly to Landlord.

          (d)  Termination of Rights. Upon any Transfer of this Lease, all
option rights, renewal or extension rights, rights of refusal and expansion
rights shall terminate and be of no further force or effect. Further, Tenant
shall not have the right to exercise any such options or rights unless Tenant
occupies the Premises and is not in default hereunder at the time of exercise.

                                       11

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     9.   MAINTENANCE BY TENANT. Tenant shall keep the Premises (including
interior surfaces of walls, ceilings, floors, doors, and interior glass
partitions) and fixtures and equipment therein in safe and sanitary condition
and good order and repair, cause no waste or injury thereto, and will, at the
expiration or other termination of this Lease, surrender the same, broom clean,
in the same order and condition they exist on the Lease Commencement Date,
ordinary wear and tear excepted. Maintenance and repair of all equipment and/or
fixtures within or for the exclusive benefit of the Premises, including, but not
limited to, kitchen fixtures, special air conditioning equipment, bathroom
fixtures, computers, or any other type of equipment or improvements, together
with related plumbing, electrical, or other utility services, whether installed
by Tenant or by Landlord on Tenant's behalf, shall be Tenant's sole
responsibility, and Landlord shall have no obligation in connection therewith.

     10.  HOURS OF OPERATION AND SERVICE.

          (a)  Ordinary Services. The regularly scheduled hours of operation for
the Building shall be 8:00 a.m. to 7:00 p.m., Monday through Friday, and 8:00
a.m. to 1:00 p.m., Saturday (excepting the following holidays: New Year's Day,
Washington's Birthday, Memorial Day, Independence Day, Labor Day, Veterans Day,
Thanksgiving Day and Christmas Day, and such other holidays as are observed by
the federal government). Landlord shall furnish heat or air conditioning as, in
Landlord's reasonable judgment, is required for the comfortable use and
occupancy of the Premises and in order to maintain the quality and nature of the
Building as a first-class office building, provided that Tenant complies with
the recommendations of Landlord's engineer fort the use and occupancy of the
Premises, to or for the benefit of the Premises during such regularly scheduled
hours. Landlord shall furnish reasonably adequate electric current which is
sufficient to operate standard office equipment including copy machines, desk
top computers and lighting; water; lavatory supplies; automatically operated
elevator service; and normal and usual cleaning and janitorial service. Such
utilities and services shall be furnished at Landlord's expense subject to the
operation and effect of Section 4 above. Landlord and its agents shall not be
liable for a failure to furnish or for suspension or delay in furnishing any or
all of such utilities or services, whether caused by breakdown, removal from
service for maintenance or repair work, strike, riot, civil commotion, or any
other cause or reason whatsoever. Any such failure or inability to furnish the
utilities or services required hereunder shall not be construed as an eviction,
actual or constructive, of Tenant from the Premises and shall not entitle Tenant
to terminate this Lease or to an abatement of any rent payable hereunder.
Landlord hereby agrees to use commercially reasonable efforts to restore such
utilities or services as soon as possible in the event of any failure of the
same.

          Tenant shall have access to the Building (including the parking
garage) twenty-four (24) hours per day, seven (7) days per week. At lease one
(1) elevator will be available at all times to allow Tenant to reach the
Premises and the parking garage.

          (b)  Extra Services. Landlord is not obligated to provide to or for
the benefit of the Premises any of the services referred to in subsection (a)
above other than during the hours and on the days referred to therein. If Tenant
desires air conditioning or heat and/or other utilities or services beyond the
hours and days as set forth above, and if a written request is made

                                       12

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to the building manager not less than twenty-four (24) hours in advance of the
requirement, Landlord shall make reasonable efforts to furnish such additional
air conditioning or heat and/or other utilities or services to Tenant, and
Tenant shall pay to Landlord as additional rent the additional costs of such
services in an amount equal to Twenty-Five Dollars ($25.00) per hour for each
one-half (1/2) floor of the Premises using each additional services on an
overtime basis, within ten (10) days of receipt of a bill for such costs. If
Tenant shall have failed to pay a previous bill for such costs, or shall be in
default of any other material provision contained in this Lease, Landlord may
refuse to provide the requested extra service(s).

     11.  TENANT ALTERATIONS; INSTALLATION OF FIXTURES.

          (a)  Restrictions on Alternations. Tenant shall not make or permit
anyone to make any alterations (including paint, wall-covering or carpeting),
additions, or improvements structural or otherwise, or to install any fixtures
(hereinafter collectively referred to as "Alterations"), in or to the Premises
or the Building without Landlord's prior written consent, which consent shall
not be unreasonably withheld or delayed. Before commencing work on any
Alterations, Tenant shall obtain Landlord's written approval of (i) the
contractor(s) and subcontractor(s) selected to perform such work, and (iii)
comprehensive plans and specifications showing all the proposed Alterations,
including detailed descriptions of the effect, if any, of the proposed
Alternations on the mechanical and electrical systems of the Building. Landlord
shall have the right to stop work on any Alterations if Landlord or its
designated agent reasonably determines that the work is not being done in a
workmanlike manner or in accordance with the plans and specifications provided
to Landlord. In such event, Tenant shall promptly correct the problem(s) which
gave rise to the work stoppage. If Tenant fails to make the necessary
corrections within a time period determined by Landlord to be reasonable, then
Landlord may, at its sole option, correct the problem(s), and complete the
Alterations, and Tenant shall be liable for the costs of such action as
additional rent. Tenant shall pay to Landlord or its designated agent reasonable
inspection and engineering fees and allow Landlord or its designated agent to
inspect the work from time to time during the period of construction of all
Alternations. In addition, Tenant shall furnish "as built" plans and
specifications for all Alterations, and pay to Landlord or its designated agent
a reasonable fee for updating the master reproducible Building blueprint to show
the Alterations.

          (b)  Conditions on Alternations. Before commencing construction of any
Alterations consented to by Landlord, Tenant shall agrees to obtain and deliver
to Landlord written and unconditional waivers of mechanic's and materialman's
liens upon the Property for all work, labor, and services to be performed, and
materials to be furnished for such work, signed by all contractors,
subcontractors, materialmen, and laborers to become involved in such work. If,
notwithstanding the foregoing, any mechanic's or materialman's lien is filed
against the Property for work claimed to have been down for, or materials
claimed to have been furnished to Tenant, Tenant shall discharge such lien
within ten (10) days thereafter, at Tenant's sole cost and expense, by the
payment thereof or by the filing of any bond required by law. If Tenant fails to
discharge any such mechanic's or materialman's lien, Landlord may, at its
option, discharge the same and treat the cost thereof and any legal expenses
incurred in connection therewith, as additional rent payable with the next due
installment of Monday Base Rent; it being hereby expressly covenanted and agreed
that such discharge by Landlord shall not be deemed to waive

                                       13

<PAGE>

or release the default of Tenant in not discharging the same. The parties
acknowledge and agree that any such Alterations shall be constructed on Tenant's
behalf and at Tenant's sole cost and expense, and Landlord's consent to such
Alterations shall not be deemed Landlord's agreement to subject Landlord's
interest in the Property to any mechanic's or materialman's liens which may be
filed in respect of any such Alterations.

          (c)  Tenant's Indemnification. Tenant shall indemnify and hold
Landlord harmless from and against any and all expenses, liens, claims, or
damages to any person or property which may or might arise directly or
indirectly by reason of making any such Alterations.

          (d)  Ownership of Alterations. Any and all Alterations to, and all
other property (including wall-to-wall carpet and wall covering), in, or upon,
the Premises shall, unless Landlord elects otherwise, become Landlord's property
without payment therefore by Landlord and shall remain upon the Premises and be
surrendered with the Premises at the expiration or termination of this Lease
(including any renewal or extension period). If Landlord elects that Alterations
made by Tenant be removed upon the expiration or termination of the Lease
(including any renewal or extension period). If Landlord elects that Alterations
made by Tenant shall cause the same to be removed at Tenant's sole cost and
expense, and shall restore the Premises to its original improved condition,
ordinary wear and tear excepted, on or before the date of this Lease expires or
is terminated. If Tenant fails to remove the same or restore the Premises,
Landlord may cause the Alterations to be removed and/or to restore the cost of
such removal and/or restoration together with any and all damages which Landlord
may suffer and sustain because of Tenant's failure to remove the Alterations
and/or restore the Premises as herein provided.

          (e)  Ownership of Non-Fixtures. If Tenant is not in default in
performing any of its obligations under this Lease, Tenant may remove, before
the Term of this Lease expires or is terminated, all movable equipment,
furniture or furnishings which are not affixed to the Premises or the Building
and which were placed in the Premises at Tenant's expense. If Tenant fails to
remove such property before this Lease expires or is terminated, unless the
parties reach prior agreement to the contrary, the same shall become Landlord's
property and shall be surrendered with the Premises as a part thereof, or, at
Landlord's option, Landlord may cause the same to be removed and Tenant shall
pay to Landlord the cost of such removal together with any and all damages that
Landlord suffers and sustains because of Tenant's failure to comply with such
obligation.

     12.  ADVERTISING.

          (a)  Restriction on Advertising. Except as otherwise herein provided,
Tenant shall not inscribe, paint or affix any sign, advertisement, display or
notice to any part of the Property, except on the directories and doors of
offices, and then only in such size, color and style as Landlord reasonably
approves. Landlord shall have the right to prohibit any advertisement, or
display of items by Tenant, wherever appearing, which in Landlord's reasonable
opinion tends to impair the reputation of the Building or its desirability as a
first class executive office building. Upon written notice from Landlord, Tenant
shall immediately refrain

                                       14

<PAGE>

from and discontinue such advertisement. If Tenant violates the terms of this
Section, Landlord may remove any sign, advertisement, display or notice and may
charge Tenant for any costs Landlord incurs in connection with such removal.

          (b)  Building Directory. Landlord shall display in the main lobby of
the Building, a building directory listing Tenant and a reasonable number of
Tenant's key personnel as specified by Tenant. The directory shall be maintained
and updated at no cost to Tenant throughout the Term of this Lease.

     13.  INSPECTIONS; ENTRY. Tenant shall permit Landlord, its agents or
employees to enter the Premises at all reasonable times to (a) examine, inspect
or protect the same; (b) prevent damage to the same and/or to any other portion
of the Building; (c) make such alternations, additions, improvements and repairs
to the Building as Landlord deems necessary or desirable, or to the Premises as
may be required by any governmental agency; or (d) exhibit the Premises to
prospective tenants during the last six (6) months of the Term of this Lease, or
any renewal or extension period, or to prospective purchasers of the Building,
or any portion thereof, at any time. None of the above shall be construed as an
actual or constructive eviction of Tenant. The rent reserved shall not abate
while such alterations, additions, improvements or repairs are being made, or
because of such entries or inspections. Landlord shall use reasonable efforts to
minimize disruption to Tenant's business because of such activities, and unless
doing so is impractical or unreasonable because of an emergency, Landlord shall
(i) comply with Tenant's security regulations and (ii) give Tenant prior notice
of its intention to enter the Premises.

     14.  INSURANCE.

          (a)  Increase in Risk. Tenant shall not conduct or permit to be
conducted any activity nor shall Tenant place any equipment in or about the
Premises or the Property which will, in any way, increase the rate of, or cause
the cancellation of, any policy of insurance of any kind covering any or all of
the Property or any liability of Landlord in connection therewith. If any
insurance company or the applicable insurance rating bureau states that any
increase in the rate of insurance is due to an activity or equipment of Tenant
in or about the Premises or the Property, such statements shall be conclusive
evidence that the increase in such rate is due to such activity or equipment,
and, as a result thereof, Tenant shall be liable for such increase and shall
reimburse Landlord therefore upon demand. Any such sum due Landlord shall be
considered additional rent payable hereunder. If any activity, equipment or
improvement done, installed or constructed by Tenant in or to the Premises shall
violate any requirements of Landlord's insurer(s), Tenant shall take prompt
action to comply with such regulation at Tenant's sole cost and expense.

          (b)  Insurance to be Maintained by Tenant. Tenant shall maintain at
its sole cost and expense throughout the Term the following:

               (i)     Commercial general liability insurance with a minimum
combined single limit of $1,000,000 per occurrence, including bodily injury and
property damage occurring within the Premises or arising out of the use thereof
by Tenant or its agents,

                                       15

<PAGE>

employees, officers or invitees, visitors and guests. If this insurance applies
to more than one locations of the insured, then a per location endorsement must
be attached to the policy;

               (ii)    All Risk Property Coverage or its equivalent form for the
full replacement value of Tenant's personal property; and

               (iii)   Business income insurance. Business income is defined as
(a) net income, net profit or loss from income taxes that would have been earned
or incurred; and (b) continuing normal operating expenses, including payroll,
incurred.

          (c)  Insurance Requirements. Said insurance shall be underwritten by a
company or companies licensed to do business in the Commonwealth of Virginia and
rated not lower that "Class A-VII", as rated in the most recent edition of
"Best's Key Rating Guide" for insurance companies, and shall be in minimum
amounts as set forth in the Rules and Regulations as reasonably established by
landlord from time to time (a copy of the current Rules and Regulations is
attached hereto as Exhibit C). Such liability insurance policy shall name
Landlord and Landlord's designated management agency (and, at Landlord's
request, any holder or a Deed of Trust or Mortgage) as additional insureds, as
their interests may appear, and shall contain an endorsement that said insurance
shall remain in full force and effect notwithstanding that the insured has
waived its right of action against any party before the occurrence of a loss. A
current Certificate of Insurance from such insurer shall be delivered to
Landlord's agent not less than thirty (30) days before the Lease Commencement
Date and renewals thereof shall be delivered to Landlord's agent not less than
thirty (30) days before the expiration of any such policy. Each policy shall
contain an endorsement prohibiting its cancellation before the expiration of
thirty (30) days after written notice to Landlord of such proposed cancellation
and shall include an endorsement stating that said insurance shall remain in
full force and effect notwithstanding the fact that the insurer has waived its
right of subrogation before the occurrence of a loss.

          (d)  Mutual Waiver of Subrogation. Whenever (1) any loss, cost,
damage, or expense resulting from fire, explosion or any other casualty or
occurrence is incurred by either of the parties to this Lease, or anyone
claiming by, through, or under it in connection with the Premises, and (2) such
party is then covered in whole or in part by insurance with respect to such
loss, cost, damage, or expense or is required under this Lease to be so insured,
then the party so insured (or so required) hereby releases the other party from
any liability said other party may have because of such loss, cost, damage or
expense to the extent of any amount recovered because of such insurance (or
which could have been recovered had such insurance been carried as so required)
and waives any right of subrogation which might otherwise exist in or accrue to
any person on account thereof.

     15.  DAMAGE TO PREMISES. All damage to the Premises, including but not
limited to damage to carpeting, wall finishes, and other Leasehold Improvement,
or to the common areas, in any way caused by Tenant or its agents, employees,
contractors, visitors, guests and invitees, shall be repaired at Tenant's
expense. If any such damage occurs, Landlord shall make such repairs as are
necessary, and Tenant shall pay any charge, costs or damages Landlord so incurs.
Such charges, costs or damages shall be deemed to be additional rent,

                                       16

<PAGE>

payable with the next due installment of Monthly Base Rent. This provision shall
be construed as an additional remedy granted to Landlord, not in limitation of
any other rights and remedies of Landlord.

     16.  LIABILITY OF LANDLORD.

          (a)  Tenant's Property and Person. All Tenant's property contained in
the Premises shall be and remain there at Tenant's sole risk except as herein
provided. Landlord, its agents and employees shall not be liable for any
accident or damage to Tenant's property absent the gross negligence of Landlord,
its agents or employees. Landlord, its agents and employees shall not be liable
for any interruption or loss of Tenant's business. Landlord, its agents and
employees shall not be liable for any personal injury to Tenant arising from the
use, occupancy and/or condition of the Premises absent the gross negligence of
Landlord, its agents or employees. For the purpose of this Section, the term
"Tenant" includes Tenant, its agents, employees, contractors, visitors, guests
and invitees.

          (b)  Indemnification of Landlord. Tenant shall indemnify and hold
Landlord and its agents and employees harmless from and against all loss,
damage, liability, cost or expenses (including attorneys fees) incurred,
suffered, or claimed against Landlord, directly or indirectly, by any person or
entity by reason of injury, loss, or damage to any person, property or business
base on, arising out of, or resulting from any default hereunder by Tenant, or
from Tenant's willful misconduct, negligence or unlawful use of the Premises or
the Property or anything therein, including water, steam, electricity, or other
facilities or equipment. Landlord, its agents and employees assume no liability
or responsibility whatsoever for the conduct or operation of the business Tenant
conducts in the Premises, and they shall not be liable for any accident or
injury to any person or property that the conduct or operation of Tenant's
business causes. Tenant shall indemnify and hold harmless Landlord, its agents
and employees, against all such claims.

          (c)  Indemnification of Tenant. Landlord shall indemnify and hold
Tenant and its agents harmless from and against any and all loss, damage,
liability, cost or expense (including reasonable attorneys' fees) incurred,
suffered, or claimed against Tenant directly or indirectly, by any person or
entity by reason of injury, loss or damage to any person, property or business
based on, arising out of, or resulting from the gross negligence or willful
misconduct or Landlord.

          (d)  Non Recourse Liability. Tenant agrees that if Tenant is awarded a
money judgment against Landlord, Tenant's sole recourse for satisfaction of such
judgment shall be limited to execution against Landlord's estate and interest in
the Property; in no event shall any other assets of Landlord, or of any partner
of Landlord or any other person or entity be available to satisfy, or be subject
to, such judgment, nor shall any partner of Landlord or any other person or
entity be held to have any personal liability for satisfaction of any claims or
judgments that Tenant may have against Landlord and/or any partner of in such
partner's capacity as a partner of Landlord.

                                       17

<PAGE>

     17.  CASUALTY.

          (a)  Partial Destruction. If the Premises are partially destroyed due
to fire or other casualty during the Term of this Lease, Landlord shall
diligently proceed to repair and restore the Premises substantially to their
condition before such casualty, taking into account the time Landlord requires
to effect a settlement with its insurance company, and to procure any insurance
proceeds. However, Landlord shall not be obligated to repair, restore or replace
any fixtures, improvements, furniture or other property Tenant owns or installs.
If the restoration of the Premises is not substantially completed within one
hundred and fifty (150) days of the date of the casualty, Tenant may terminate
this Lease by giving Landlord thirty (30) days notice thereof. During the period
that Tenant is deprived of the use of the damaged portion of the Premises, the
rent for the remainder of the Premises shall be that portion of the total rent
which the area remaining that can be occupied bears to the total area of the
Premises. Except as set forth above, no compensation or claims or abatement of
rent shall be allowed or paid by Landlord because of inconvenience, annoyance or
injury to Tenant's business, arising from the repair of the Premises or the
Property.

          (b)  Substantial Destruction. If during the Term of this Lease the
Premises or the Building are so damaged by fire or other casualty that either
one is rendered substantially unfit for occupancy, to be reasonably determined
by landlord, then Landlord may elect to terminate this Lease as of the date of
such casualty, by giving written notice thereof to Tenant within sixty (60) days
after such date, in such case the rent and additional rent shall be apportioned
and paid to the date of said fire or other casualty. If there is damage to or
destruction of the Building that exceeds twenty-five percent (25%) of the
replacement value of the Building from any cause, whether or not the Premises
are damaged or destroyed, Landlord shall have the right to terminate this Lease
by written notice as set forth above.

          (c)  Damage to Tenant's Property. Tenant acknowledges that Landlord
shall not carry insurance of any kind on Tenant's furniture and furnishings, or
on any fixtures or equipment removable by Tenant under the provisions of this
Lease, and that Landlord is not obligated to repair any damage thereto or to
replace the same. In addition, Landlord is not obligated to repair any damage or
injury to, or to replace, any Leasehold Improvement or Alterations made or
installed in the Premises.

     18.  CONDEMNATION.

          (a)  Substantial Condemnation. Tenant agrees that if the entire or a
substantial part of the Premises, or the use of occupancy thereof, are taken or
condemned, for public or quasi-public use or purpose by any competent authority,
or sold under the threat of condemnation to any competent authority, this Lease
will terminate as of the date of any such taking and all rent payable hereunder
shall be apportioned as of that date. Tenant shall have no claim against
Landlord and shall have no claim or right to any portion of any award, damages
or other compensation made to landlord because of any such taking of
condemnation, or sale under the threat of such a taking. Tenant hereby assigns
to Landlord all of Tenant's rights, if any, to such awards, damages and
compensation therefore. Upon such condemnation or taking, the Term of this Lease
shall terminate as of from the date of such taking or condemnation, an Tenant

                                       18

<PAGE>

shall have no claim against Landlord for the value of any unexpired Term of this
Lease, Leasehold Improvements, the loss of profits or good will, or severance
damages. Notwithstanding the foregoing, Tenant may pursue a separate claim
against the condemning authority, provided that any award to Tenant does not
diminish any award made to Landlord.

          (b)  Partial Condemnation. If less than a substantial part of the
Premises is taken or condemned, the rent for the remainder of the Premises shall
be that portion of the total rent which the area remaining that can be occupied
bears to the total area of the Premises, effective on the date when title vests
in such governmental authority. The Lease shall otherwise remain in full force
and effect. For purposes hereof, a substantial part of the Premises shall be
considered to have been taken if more than one-third (1/3) of the rentable area
of the Premises is rendered unusable as a result of such condemnation.
Notwithstanding anything to the contrary herein contained, if twenty-five
percent (25%) or more of the Building or the Land is taken, condemned or sold
under the threat of such a taking, Landlord may, at its sole option, terminate
this Lease as of the date of the taking.

     19.  DEFAULT.

          (a)  Events of Default. The occurrence of any of the following shall
constitute an "Event of Default" and breach of this Lease by Tenant:

               (i)     If Tenant fails to pay on the due date the Monthly Base
Rent, additional rent or any other monetary sums required to be paid hereunder,
and Tenant fails to cure such nonpayment within seven (7) days after receipt of
written notice from Landlord; or

               (ii)    If Tenant abandons or vacates the Premises or Tenant
fails to take possession of the Premises within thirty (30) days following the
date Landlord tenders possession of the Premises to Tenant; or

               (iii)   If Tenant fails to observe or perform any other provision
of this Lease to be observed or performed by Tenant, where such failure
continues for thirty (30) days after written notice thereof by Landlord to
Tenant; provided, however, that if such default is nonmonetary and cannot
reasonably be cured within thirty (30) days, then the default shall not be
deemed to be uncured if Tenant commences to cure within thirty (30) days from
Landlord's notice and continues to prosecute diligently the completion of cure
thereof within a reasonable time not to exceed ninety (90) days; or

               (iv)    If Tenant makes any general assignment or general
arrangement for the benefit of creditors; if there is filed by or against Tenant
a petition to have Tenant adjudged a bankrupt or if a petition for
reorganization or arrangement is filed under any law relating to bankruptcy
(unless, in the case of a petition filed against Tenant, the same is dismissed
within sixty (60) days); if a trustee or receiver is appointed to take
possession of all or substantially all of Tenant's interest in this Lease; if
all or substantially all of Tenant's assets located at the Premises or Tenant's
interest in this Lease are attached, executed upon or otherwise subjected to
other judicial seizure, where such seizure is not discharged within thirty (30)
days; or if Tenant is generally not paying its debts as they become due;
provided, however, in no event shall this

                                       19

<PAGE>

Lease be assigned or assignable by operation of law or by voluntary or
involuntary bankruptcy proceedings or otherwise, and in event shall this Lease
or any rights or privileges hereunder be an asset of Tenant under any
bankruptcy, insolvency, reorganization or other debtor relief proceedings; or

               (v)     If Tenant fails to pay the Monthly Base Rent or any
additional rent on the due date thereof more than three (3) times during any
calendar year (even if Tenant cures each such failures within the time provided
in subsection (i) above); or

               (vi)    If this Lease or Tenant's interest hereunder or
possession of all or part of the Premises are transferred to or pass to or
devolve upon any other person or entity in violation of any provision contained
in this Lease.

          (b)  Landlord's Rights and Remedies in Event of Default. If an Event
of Default occurs, Landlord may at any time thereafter, in its sole discretion,
without limiting Landlord's exercise of any other right or remedy Landlord has
under this Lease, at law or in equity, because of such default or breach,
exercise the following rights:

               (i)     Terminate this Lease and Tenant's right of possession of
the Premises upon written notice to Tenant, effective on the date specified in
such notice, and recover (a) all damages to which Landlord is entitled under
law, including, without limitation, all rental concessions, repair and
alteration costs, brokerage commissions, legal fees and other expenses of
reletting the Premises; or (b) the total amount of Base Rent and Additional Rent
payable under this Lease from the date of termination until the Lease Expiration
Date. Upon such termination, every obligation of the parties shall cease as of
the date of such termination, except that Tenant shall remain liable to pay all
rent and other sums accrued up to the date of termination or recovery or
possession Landlord, whichever is later, and to perform all terms and
obligations of this Lease which expressly survive termination hereof. The notice
of termination provided hereunder shall operate as a notice to quit, and Tenant
waives any other notice to quit or notice of Landlord's intention to re-enter
the Premises; or

               (ii)    Without terminating this Lease and without entering into
possession of the Premises, continue this Lease in effect and to enforce all
Landlord's rights and Tenant's obligations hereunder, including filing suit to
collect Monthly Base Rent, additional rent, and all other sums due hereunder as
they accrue (including attorneys' fees and other damages). Acts of maintenance
or preservation, efforts to relet the Premises, or appointing a receiver upon
Landlord's initiative to protect its interest under this Lease shall not
constitute a termination of this Lease or Tenant's right to possession
hereunder; or

               (iii)   Without terminating this Lease, reenter and retake
possession of the Premises and any all Leasehold Improvement from Tenant by
summary proceedings or otherwise, and remove, or cause to be removed, Tenant or
any other occupants from the Premises in such a manner as Landlord deems
appropriate, with or without legal process and using self-help, if deemed
appropriate by Landlord. The commencement and prosecution of any action by
Landlord in an unlawful detainer, ejectment or otherwise, or any execution of
any judgment or decree obtained in any action to recover possession of the
Premises, or any other re-entry and

                                       20

<PAGE>

removal, shall not constitute a termination of this Lease, and shall not be
deemed to have absolved or discharged Tenant from any of its obligations or
liabilities for the remainder of the Term, nor shall Landlord be liable for the
prosecution therefore, or be deemed guilty of any trespass. Tenant shall,
notwithstanding any such entry or re-entry, remain liable to pay rent and
perform the other covenants, conditions and agreements by Tenant to be performed
as set forth in this Lease. Thereafter, Landlord shall have the right, and shall
use reasonable efforts, to relet the Premises for Tenant's account, in whole or
in part, or together with other space, for such Term or Terms (which may be
greater or less than or equal to the unexpired portion of the Term) upon such
provisions (including concessions) and for such rental as Landlord in its sole
discretion determines appropriate, and to collect and receive said rental.
Landlord shall not be liable for, nor shall Tenant's obligations hereunder be
diminished because of, any failure of Landlord to relet the Premises or any
failure of Landlord to collect all rent due upon such reletting. If and when the
Premises are relet a sufficient sum is not realized from such reletting, after
paying all Landlord's expenses of reletting (including, without limitation,
rental concessions, brokerage commissions, legal fees, repairs and alterations),
and to satisfy Tenant's obligations to pay Monthly Base Rent and additional rent
hereunder, Tenant shall pay any deficiency to Landlord on demand. Tenant shall
have no right to any excess rent that Landlord recovers because of such
reletting. No notice from Landlord hereunder or under a forcible entry and
detainer statute or similar law shall constitute an election by Landlord to
terminate this Lease unless such notice specifically so states. Landlord
reserves the right following any such re-entry and/or reletting to terminate
this Lease by giving Tenant such written notice, in which event this Lease will
terminate as specified in said notice.

               (iv)    The right, but not the obligation, to remove from the
Premises all or any part of any personal property located therein and to sell
such property and apply the proceeds to any damages Landlord incurs, or to place
the same in storage at a public warehouse at the expense and risk of the owner
or owners thereof, without liability therefore.

               (v)     Cure such Event of Default in any other manner, in which
event Tenant shall reimburse Landlord for all expenses Landlord incurs in doing
so, plus interest thereon at rate of eighteen percent (18%) per annum, or the
maximum rate permitted by law, whichever is less, which expenses and interest
shall be additional rent payable by Tenant immediately upon Landlord's demand.

               (vi)    In addition to the foregoing, Landlord may recover from
Tenant as damages any other amount necessary to compensate landlord for all the
detriment proximately caused by Tenant's failure to perform its obligations
under this Lease or which in the ordinary course of events would be likely to
result therefrom, including without limitation, commissions, advertising costs,
costs of Leasehold Improvements, costs of making any alterations or repairs in
the Premises and reasonable attorneys' fees, and, to the extent permitted by
law, the value and/or cost of all concessions to Tenant under this Lease
(including without limitation, rental abatements, allowances, and assumption of
rental obligations to third parties); and

               (vii)   Pursue any individual remedy or any combination of the
remedies set forth in this subsection (b).

                                       21

<PAGE>

          (c)  Legal Action. Landlord may, at its election, bring a suit or
suits to recover the amounts and damages set forth above, and nothing herein
shall be deemed to require Landlord to await the date whereon this Lease or the
Term hereof would have expired by limitation had there been no such default by
Tenant or no such termination, as the case may be. Each right and remedy
provided for in this Lease is cumulative and in addition to every other right or
remedy provided for in this Lease or now or hereafter existing at law or in
equity or by statute or otherwise, including, but not limited to, suits for
injunctive relief and specific performance. The exercise or beginning of the
exercise by Landlord of any one or more of the rights or remedies provided for
in this Lease or now or hereafter existing at law or in equity or by statute or
otherwise shall not preclude Landlord's simultaneous or later exercise of any
and all other rights or remedies provided for in this Lease or now or hereafter
existing at law or in equity or by statute or otherwise. Landlord may also
recover from Tenant all costs Landlord incurs in collecting any amounts or
damages Tenant owes pursuant to the provision of this Lease, including
reasonable attorneys' fees from the date any such matter is turned over to an
attorney.

          (d)  Injunctive Relief. If Tenant breaches or threatens to breach any
of the covenants or provisions of this Lease, Landlord shall have the right of
injunctive relief and the right to invoke any remedy allowed at law or in
equity; and in such event Landlord shall be entitled to recover from Tenant,
payable as additional rent hereunder, any and all reasonable expenses Landlord
incurs in its efforts to secure such injunctive relief or other remedy at law or
in equity, such as court costs and attorneys' fees.

          (e)  Independent Obligations. If Landlord commences any proceeding for
non-payment of rent, or any other payment of any kind to which Landlord is
entitled or which it may claim hereunder, Tenant shall not interpose any
counterclaim or set-off of whatever nature of description in any such
proceeding, the parties hereto specifically agreeing that Tenant's covenants to
pay rent or to make any other payments required of it hereunder are independent
of all other covenants and agreements herein contained, provided, however, that
this shall not be construed as a waiver of Tenant's right to assert such a claim
in any separate action brought by Tenant. Tenant further waivers any right or
defense which it may have to claim a merger, and neither the commencement of any
action or proceeding, nor the settlement thereof, nor entering of judgment
therein, shall bar Landlord from bringing subsequent actions or proceedings from
time to time. Tenant expressly waives any and all right of redemption granted by
or under any present or future laws if Tenant is evicted or dispossessed for any
cause, or if Landlord obtains possession of the Premises because Tenant violates
any o f the covenants and conditions of this Lease, or otherwise.

          (f)  Compromise or Settlement. If legal proceedings are instituted
hereunder, and a compromise or settlement thereof is made, it shall not be
constituted as a waiver of any subsequent breach of any covenant, condition or
agreement herein contained.

          (g)  Acceptance of Payment. No payment by Tenant or receipt by
Landlord of a lesser amount than the Monthly Base Rent herein stipulated shall
be deemed to be other than on account of the earliest stipulated rent then due,
nor shall any endorsement or statement on any check or any letter accompanying
any check or payment without prejudice to Landlord's right to recover the
balance of such rent or to pursue any other remedy.

                                       22

<PAGE>

          (h)  Repudiation. If, before the commencement of the Term of this
Lease, Tenant notifies Landlord of, or otherwise unequivocally demonstrates an
intention to, repudiate this Lease, Landlord may, at its option, consider such
anticipatory repudiation a breach of this Lease. In addition to any other
remedies available to it hereunder or at law or in equity, Landlord may retain
all rent paid upon execution of the Lease, and the security deposit, if any, to
be applied to damages of Landlord incurred as a result of such repudiation,
including, without limitation, attorneys' fees, brokerage fees, costs of
re-letting and loss of rent. The parties agree that for the purpose of
calculating Landlord's damages, in a building which has other available space at
the time of Tenant's breach, Landlord shall have no obligation to rent the
Premises before other space in the Building.

          (i)  Landlord's Lien. Landlord shall have a lien upon Tenant's
property in the Premises during the Lease Term for the amount of any unpaid rent
or other sum due from Tenant hereunder. Landlord shall have the right and
privilege, at its sole option and discretion, to take possession of all Tenant's
property in the Premises, to store the same in the Premises, or to remove it
from the Premises and store it in such place as Landlord may select, at Tenant's
risk and expense, in accordance with such lien and of any rights of distraint
Landlord may possess against Tenant's property. Provided, however, so long as
Tenant is not in default hereunder, Landlord will subordinate the lien set forth
in this subsection (i) to any purchase money financing or personal property
leases request by Tenant.

     20.  SUBORDINATION.

          (a)  Subordination of Lease. This Lease is subject and subordinate to
the lien, operation and effect of all ground leases, deeds of trust, mortgages,
and/or other similar instruments of encumbrance (herein each referred to for the
purposes of this Section 20 as "Mortgages") which may now or hereafter affect
this Lease or the Property, to all funds and all indebtedness intended to be
secured by such Mortgages, and to all renewals, modifications, consolidations,
replacements and extensions thereof. This clause shall be self-operative and no
further instrument of subordination shall be necessary to effect the
subordination of this Lease to the lien of any such Mortgage. In confirmation of
such subordination, Tenant shall, within five (5) days of the written request of
Landlord or the holder of any Mortgage, executive promptly any further
instruments requested. Tenant constitutes and appoints Landlord as Tenant's
attorney-in-fact to execute any such instruments for or on Tenant's behalf if
Tenant fails to execute and deliver such instrument(s) within said five (5) day
period. Landlord shall cause the holder of the Mortgage currently affecting the
Property to execute a Non-Disturbance, Attornment and Subordination Agreement in
the form attached hereto and incorporated herein by reference as Exhibit F.
Landlord hereby agrees to use commercially reasonably efforts to obtain a
non-disturbance agreement for Tenant from any future Mortgagee, but Landlord's
failure to obtain the same shall not affect the enforceability of the terms of
this Lease.

          (b)  Foreclosure. In the vent of any proceeding to terminate or to
foreclose upon any Mortgage to which this Lease is subordinate, the ground
lessor, purchaser, assignee or other successor to Landlord's rights shall have
the option to terminate or cancel this Lease, except as provided under any
applicable non-disturbance agreement between Tenant and any

                                       23

<PAGE>

such party. If this Lease is not so terminated or cancelled, Tenant shall attorn
to the purchaser at the foreclosure sale and shall recognize such purchaser as
the landlord pursuant to this Lease. Upon request by such purchaser, Tenant
shall execute and deliver an instrument or instruments confirming its
attornment.

          (c)  Modification Required by Lender. If any lender providing any
financing for the Building requires, as a condition of that financing, that
modifications to the Lease be obtained, and provided that the modifications do
not increase the rent and other sums to be paid by Tenant hereunder nor
materially affect Tenant's use of the Premises, Landlord may submit to Tenant a
written amendment to the Lease incorporating the required changes, and Tenant
shall execute, acknowledge and deliver such amendment to Landlord within five
(5) days of Tenant's receipt thereof.

          (d)  Subordination of Mortgage to Lease. Anything contained in the
provisions of this Section to the contrary notwithstanding, the holder of any
Mortgage may at any time subordinate the lien of its Mortgage to the operation
and effect of this Lease without obtaining Tenant's consent thereto, by giving
Tenant written thereof, in which event this Lease shall be deemed to be senior
to such Mortgage without regard to their respective dates of execution, delivery
and/or recordation, and thereafter such Mortgagee shall have the same rights, as
to this Lease as it would have had, were this Lease executed and delivered
and/or recorded before the execution of such Mortgage.

     21.  JURY TRIAL. The parties waive the right to trial by jury in any
action, proceeding or counterclaim brought by either of the parties hereto
against the other on any matters whatsoever arising out of or in any way
connected with this Lease, the relationship of Landlord and Tenant, Tenant's use
of occupancy of the Premises and/or any claim of injury or damage.

     22.  HOLDOVER. If Tenant remains in the Premises after the expiration of
the Term or any earlier termination of this Lease without obtaining Landlord's
prior written consent thereto, Tenant shall become a tenant from month to month
at double the Monthly Base Rent in effect during the last month of the Term.
Provided however, at any time before Landlord's acceptance of rent from Tenant
as a monthly tenant hereunder, Landlord, at its option, may re-enter and take
possession of the Premises without process, or by any legal process permitted
under the provisions of this Lease or applicable law because of Tenant's
occupancy of the Premises without having obtained such consent.

     23.  SUCCESSORS' OBLIGATION. Landlord and Tenant agree that all rights,
remedies and liabilities hereunder given to or imposed upon either of the
parties hereto shall extend to their respective heirs, successors, executors,
administrators and assigns subject to the provisions of this Lease restricting
assignment or subletting by Tenant. Tenant acknowledges Landlord might not be in
the future the owner of the fee interest in the Building and/or Land. The term
"Landlord" as used in this Lease means only the then current owner or mortgagee
in possession of the Building. Upon any sale or sales by the then current
Landlord hereunder to any party then, from and after the closing of such sale or
lease transaction, Landlord whose interest is

                                       24

<PAGE>

thus sold or leased shall be and hereby is completed released and forever
discharged from any and all covenants, obligations and liabilities of Landlord
hereunder thereafter accruing.

     24.  RULES AND REGULATIONS. Landlord may prescribe, in its sole discretion,
reasonable rules and regulations, which in Landlord's reasonable judgment are
necessary or appropriate for the general well-being, safety, care and
cleanliness of the Property; provided, that the rules and regulations do not
materially interfere with Tenant's use and enjoyment of the Premises and which
rules shall be fairly enforced for all tenants in the Building. Tenant agrees
that the rules and regulations shall be faithfully kept, observed and performed
by Tenant, and by Tenant's agents, servants, employees, invitees, visitors, and
guests. Any failure by Landlord to enforce any rule or regulation against any
party shall not be deemed a waiver of such rule or regulation or of Landlord's
further right to enforce the same. A copy of the rules and regulations in effect
on the date of this Lease are attached hereto and incorporated herein by
reference as Exhibit C.

     25.  COVENANTS OF LANDLORD. Landlord covenants that it has the right to
make this Lease for the Term, and that if Tenant pays all rent when due and
punctually performs all of the covenants, terms, conditions, and agreements of
this Lease to be performed by Tenant, Tenant may, during the Term, peaceably and
quietly occupy and enjoy the full possession of the Premises.

     26.  RESERVATION OF RIGHTS OF LANDLORD. Landlord reserves to itself and its
successors and assigns the following rights (all of which are hereby consented
to by Tenant): (i) to change the street address and/or name of the Building
and/or the arrangement and/or location of entrances, passageways, doors,
doorways, corridors, elevators, stairs, toilets, or other public parts of the
Building and to make improvements, alterations, additions, installations,
eliminations and changes to the Building, Land, parking facilities, or any part
thereof; (ii) to erect use, and maintain pipes and conduits in and through the
Premises; (iii) to grant to any one the exclusive right to conduct any
particular business or undertaking in the Building; (vi) to use and/or lease the
roof areas, and the sidewalks and other exterior areas; and (vii) to resubdivide
any land on which the Building is located. Landlord may exercise any or all of
the foregoing rights without being deemed to be guilty of an eviction, actual,
or constructive, or a disturbance or interruption of Tenant's business or
Tenant's use or occupancy of the Premises. Landlord hereby agrees to use
commercially reasonable efforts to minimize any disruption to Tenant in
Landlord's exercise of its rights hereunder.

     27.  SECURITY DEPOSIT.

          (a)  Amount of Security Deposit. Simultaneously with the execution of
this Lease, Tenant shall deposit with Landlord the sum of Seven Thousand
Fifty-Four and 13/100 Dollars ($7,054.13) as a security for the payment and
performance by Tenant of all of Tenant's obligations, covenants, conditions and
agreements under the Lease (the "Security Deposit"). Such Security Deposit shall
not bear interest while being held by Landlord hereunder. Landlord's rights
against Tenant in the event of default shall in no way be limited or restricted
by the Security Deposit.

                                       25

<PAGE>

          (b)  Return of Security Deposit. Upon the expiration of the Term, or
any renewal or extension thereof, Landlord shall, provided that Tenant is not in
default under the Terms of this Lease, return the Security Deposit to Tenant,
less such portion as Landlord shall have appropriated to cure any default by
Tenant with respect to any of Tenant's aforesaid obligations, covenants,
conditions and agreements.

          (c)  Default by Tenant. If Tenant defaults hereunder, Landlord may,
but shall not be obligated, apply all or any portion of the Security Deposit to
cure such default, in which event Tenant shall deposit promptly with Landlord
the amount necessary to restore the Security Deposit to its original amount.

          (d)  Sale or Transfer of Building. Upon the sale or transfer of
Landlord's interest in the Building, Landlord may transfer the Security Deposit
to such purchaser or transferee, in which event Tenant shall look only to the
new landlord for the return of the Security Deposit and Landlord shall thereupon
be released from all liability to Tenant for the return of such Security
Deposit.

     28.  PARKING. The Parking Agreement which is attached hereto as Exhibit E
and incorporated herein by reference sets forth the rights and obligations of
the parties to use the parking facilities appurtenant to the Building. If Tenant
shall fail to pay any sum required to be paid pursuant to said Parking
Agreement, it shall be a default under this Lease, giving Landlord all the
rights and remedies set forth in this Lease, together with any further rights
under the law.

     29.  MORTGAGEE APPROVAL.

          [Deleted]

     30.  GENDER. Feminine or neuter pronouns shall be substituted for the
masculine form, and the plural shall be substituted for the singular number, in
any place or places herein where the context requires such substitution or
substitutions. Landlord and Tenant, as a matter of convenience, have been
referred to in neuter form.

     31.  NOTICES. All notices or other communications required or desired to be
given hereunder by either party to the other shall be in writing and shall be
deemed duly given if delivered in person (with receipt therefore), or if sent by
certified or registered mail, first-class postage prepaid, return receipt
requested. Notices to the respective parties shall be addressed as follows:

                                       26

<PAGE>

To Landlord:   TYCON TOWER I INVESTMENT LIMITED PARTNERSHIP
               c/o Aldrich, Eastman & Waltch, Inc.
               225 Franklin Street
               Boston, Massachusetts  02110

               Attention: Kevin McCall

               Copy to:

               AXIOM Real Estate Management, Inc.
               8000 Towers Crescent Drive
               Vienna, Virginia 22182

               Attention: Patricia Maccini-Rollins

To Tenant:     ALLIED RESEARCH CORPORATION
               8000 Towers Crescent Drive, Suite 750
               Vienna, Virginia 22182

               Attention: President

               Copy to:

               James E. Baker, Jr., Esquire
               Smith, Sommerville & Case
               100 Light Street, 5th Floor
               Baltimore, Maryland 21202

Either party may, by like written notice, designate a new address to which such
notices shall be directed.

     32.  ESTOPPEL CERTIFICATES. Tenant shall, at any time and from time to
time, upon not less than five (5) days prior written notice by Landlord,
execute, acknowledge before a Notary Public, and deliver to Landlord (or, at
Landlord's request, to any existing or prospective purchaser, transferee,
assignee or holder of a Deed or Trust or Mortgage securing any or all of the
Premises or the Property, any interest thereon or any of Landlord's rights under
this Lease) a instrument in recordable form: (i) certifying that this Lease is
unmodified and in full force (or if there have been modifications, that the
Lease is in full force and effect as modified and stating the modifications);
(ii) stating the dates to which the rent and any other charges due hereunder
have been paid by Tenant; (iii) stating whether or not, to Tenant's best
knowledge, Landlord is in default in the performance or any covenant or
condition contained in this Lease, and if so, detailing the nature of such
default; (iv) stating the address to which notices to Tenant should be sent; (v)
stating that Tenant has accepted the Premises and that all work required has
been completed by Landlord; and (vi) any other information as may be reasonably
required by Landlord. Any such statement delivered by Tenant pursuant hereto may
be replied upon by any owner of the Property, any prospective purchaser of the
Property, any holder of a deed of trust or

                                       27

<PAGE>

mortgage or prospective holder of a deed or trust of mortgage on the Property or
on Landlord's interest therein, or any prospective assignee of any such deed of
trust or mortgage. Tenant acknowledges that time is of the essence for the
delivery of such statements and that Tenant's failure to comply within the time
period specified may result in substantial damages to Landlord and that Tenant
shall be liable for all such damages suffered by Landlord.

     33.  GOVERNING LAW. The parties agree that the laws of the Commonwealth of
Virginia shall govern the validity, performance and enforcement of this Lease
and that any action or proceeding arising hereunder shall be brought in the
courts of Virginia.

     34.  COMMISSIONS. Landlord and Tenant each represent and warrant that
except as specifically set forth in this Lease, neither of them has employed any
real estate broker, agent or finder, and there is no commission change or other
compensation due on account thereof. Landlord shall indemnify and hold Tenant
harmless, and Tenant shall indemnify and hold Landlord harmless, from and
against any claim for brokerage or other commission arising from or out of any
breach of the foregoing representation and warranty. Landlord recognizes Julien
J. Studley and The Charles E. Smith Companies as the leasing agent(s) in
connection with this Lease, and shall be solely responsible for any commissions
due to said agent(s).

     35.  WAIVER OF BREACH. No delay in exercising or failing to exercise any
right or power hereunder by Landlord shall impair any such right or shall be
construed as a waiver of any breach or default, or as acquiescence thereto. One
or more waivers or any covenants, terms or conditions of this Lease by Landlord
shall not be construed by the other party as a waiver or a continuing or
subsequent breach of the same covenant, term or condition. Landlord's consent or
approval to, or of, any act by Tenant of a nature requiring consent or approval
shall not be deemed to waive or render unnecessary consent to, or approval of,
any subsequent similar act. No provision of this Lease shall be deemed to have
been waived by Landlord, unless such waiver is in writing signed by Landlord.

     36.  SEVERABILITY OF CLAUSES. If any term or provision of this Lease or the
application thereof to any person or circumstance shall to any extent be invalid
or unenforceable, the remainder of this Lease, or the application of such term
or provision to persons or circumstances other than to those as to which it is
held invalid or unenforceable, shall not be affected thereby, and each term and
provision of the Lease shall be valid and be enforced to the fullest extent
permitted by law.

     37.  CAPTIONS FOR CONVENIENCE. The titles of the sections and paragraphs
throughout this Lease and for convenience and reference only, and the words
contained therein shall in no way be held to explain, modify, amplify or aid in
the interpretation, construction or meaning of the provisions of this Lease.

     38.  DUPLICATE COUNTERPARTS ORIGINALS. This Lease may be executed in one or
more counterparts, each of which shall be deemed an original, and all of which
together shall constitute one and the same instrument.

                                       28

<PAGE>

     39.  RECORDATION. This Lease may not be recorded without Landlord's prior
written consent. If this Lease is recorded by either party hereto, such party
shall bear the full expense of any transfer, documentary stamp or other tax, and
any recording fee, assessed in connection with such recordation; provided, that
if after the date of this Lease it becomes necessary under the applicable law of
the Commonwealth of Virginia to record this Lease in order for the Lease to
remain effective, Tenant shall bear the full expense or any and all such taxes
and fees incurred in connection therewith.

     40.  EFFECTIVENESS. The submission of an unsigned copy of this document to
Tenant for Tenant's consideration does not constitute an offer to lease the
premises. This Lease shall become effective upon and only upon its execution and
delivery by each party hereto.

     41.  RIGHT TO RELOCATE.

          [Intentionally Deleted.]

     42.  NO PARTNERSHIP. Nothing contained in this Lease shall be construed as
creating a partnership or joint venture of or between Landlord and Tenant, or to
create any other relationship between the parties hereto other than that of
landlord and tenant.

     43.  TIME OF ESSENCE. Time is of the essence as to each provision of this
Lease.

     44.  FORCE MAJEURE. If Landlord is in any way delayed, interrupted or
prevented from performing any of its obligations under this Lease, and such
delay, interruption or prevention is due to fire, act of God, governmental act,
strike, labor dispute, inability to procure materials, or any other cause beyond
Landlord's reasonable control, then the time for performance of the affected
obligation(s) by Landlord shall be excused for the period of the delay and
extended for a period equivalent to the period of such delay, interruption or
prevention.

     45.  ENTIRE AGREEMENT. This Lease constitutes the entire agreement between
the parties and no prior agreements, negotiation, discussions or written matter
shall have any force or effect. Tenant is not relying on any representations or
agreements other than those contained in this Lease. This Lease shall not be
modified, cancelled, extended or renewed except for written instrument executed
and delivered by both parties.

     46.  HAZARDOUS WASTES. Tenant shall no knowingly suffer, permit, introduce
or maintain in, on or about any portion of the Property, any asbestos,
polychlorinated biphenyls, petroleum products or any other hazardous or toxic
materials, wastes and substances which are defined, determined or identified as
such in any federal, state or local laws, rules or regulations (whether now
existing or hereafter enacted or promulgated) or any judicial or administrative
interpretation of any thereof, including any judicial or administrative orders
of judgments. Any such asbestos, polychlorinated biphenyls, petroleum products
and any such other materials, wastes and substances are herein collectively
called "Hazardous Materials." Tenant shall indemnify, protect, and save Landlord
harmless against and from any and all damages, losses, liabilities, obligations,
penalties, claims, litigation, demands, defenses, judgments, suits,

                                       29

<PAGE>

proceedings, costs, disbursements or expenses of any kind or of any nature
whatsoever (including, without limitation, attorneys' and experts' fees and
disbursements) which may at any time be imposed upon, incurred by or asserted or
awarded against Landlord and arising from or out of any Hazardous Materials on,
in, under or affecting all of any portion of the Property or that are introduced
by Tenant, its employees or invitees including, without limitation, (i) the
costs of removal of any and all Hazardous Materials from all or any portion of
the Property, (ii) additional costs required to take necessary precautions to
protect against the release of Hazardous Materials on, in, under or affecting
the Property into the air, any body or water, any other public domain or any
surrounding areas, and (iii) any costs incurred to comply, in connection with
all or any portion of the property with all applicable laws, orders, judgments
and regulations with respect to Hazardous Materials. The preceding portions of
this provision do not apply to Hazardous Materials that are located on the
Property at or before the initial commencement of any work, construction,
repairs or alterations therein by Tenant or to any Hazardous Materials
introduced into the Property by anyone other than Tenant, its employees or
invitees. The obligations of Tenant under this Section 46 shall survive the
expiration or earlier termination of this Lease.

     47.  JOINT AND SEVERAL LIABILITY. If two ore more individuals, corporation,
partnerships or other business associations (or any combination of two or more
thereof) shall sign this Lease for Tenant, the liability of each such
individual, corporation, partnership or other business association to pay the
rent due under this Lease and to perform all other obligations hereunder shall
be deemed to be joint and several. All notices, payments and agreements given or
made by, with or to any one of such individuals, corporations, partnerships or
other business associations shall be deemed to have been given or made by, with
or to all of them. In like manner, if Tenant shall be a partnership or other
business association, the members of which are, by virtue or statute or federal
law, subject to personal liability, the liability of each such member shall be
joint and several.

     48.  CORPORATE TENANTS' FICTITIOUS NAMES. If Tenant is a corporation, the
persons executing this Lease on Tenant's behalf covenant and warrant that:
Tenant is a duly constituted corporation qualified to do business in the
Commonwealth of Virginia; all of Tenant's franchisee and corporate taxes have
been paid to date; all future forms, reports, fees and other documents necessary
for Tenant to comply with applicable laws will be filed by Tenant when due; and
such persons are duly authorized by the board of directors of such corporation
to execute and deliver this Lease on behalf of the corporation.

          Tenant certifies that if it is operating under a fictitious name that
said name has been duly recorded according to the laws of the Commonwealth of
Virginia and attaches hereto a copy said registration form.

     49.  CONFLICTS. If there is any conflict between the provisions of this
Lease and the provisions of any Addendum attached hereto, the provisions of the
Addendum shall supercede the provisions of said documents and this Lease and the
provisions of said documents, as amended from time to time, shall supersede the
provisions of this Lease.

                                       30

<PAGE>

                 WITNESSETH the following signatures and seals:

                                   LANDLORD:

                                   TYCON TOWER I INVESTMENT LIMITED
                                   PARTNERSHIP, a Virginia limited partnership

                                   By: TYCON TOWER I INVESTMENT
                                   CORPORATION, a Virginia corporation, its sole
                                   partner


Date:                              By:                                 (SEAL)
      --------------------             -------------------------------
                                       KEVIN MCCALL
                                       Vice President & Director

                                   TENANT:

                                   ALLIED RESEARCH CORPORATION


Date:                              By:                                 (SEAL)
      --------------------             -------------------------------
                                       Name:
                                       Title:

                                       31

<PAGE>

                                    EXHIBIT A

                  [Demising Sheet - Tycon Tower I - 7th Floor)

                                       32

<PAGE>

                                    EXHIBIT B

                                               Date: ___________________________

To:       _________________________
          _________________________
          _________________________
          _________________________

Re:       Lease dated:      ___________________________
          Premises:         ___________________________
          Landlord:         Tycon Tower I Investment Limited
                            Partnership
          Tenant:           ___________________________

Dear      ____________________________:

          In accordance with the terms of the above referenced Lease, you are
hereby notified, on behalf of Landlord, that Landlord shall tender possession of
the Premises on ________________, 19, when Tenant's obligation to pay rent shall
commence. The Lease Commencement Date shall be ____________________________,
19_______. The Lease Expiration Date shall be __________________________, 19
________.

          We have enclosed two (2) copies of this letter together with a
stamped, self-addressed envelope. Please sign both copies in the space below,
and return both copies. The original letter should be retained for your records.

                                   AXIOM REAL ESTATE MANAGEMENT, INC.


                                   By:
                                       -----------------------------------------
ACKNOWLEDGED AND AFFIRM:

-----------------------
       (TENANT)

By:
     -------------------------

Name:
       -----------------------
Title:
       -----------------------
Date:
       -----------------------

                                       33

<PAGE>

                                    EXHIBIT C
                      RULES AND REGULATIONS OF THE BUILDING

(a)  The sidewalks, entrances, passages, courts, elevators, vestibules,
     stairways, corridors or halls or other parts of the Building not occupied
     by any tenant shall not be obstructed or encumbered by any tenant or used
     for any purpose other than ingress or egress to and from the Premises.
     Landlord shall have the tight to control and operate the public portions of
     the Building, and the facilities furnished for the common use of the
     tenants, in such manner as Landlord deems best for the benefit of the
     tenants generally. Tenant shall not permit people to visit the Premises in
     such numbers or under such conditions as to interfere with the use and
     enjoyment by other tenants of the entrances, corridors, elevators and other
     public operations or facilities of the Building.

(b)  Tenant shall not attach awnings or other projections to the outside walls
     of the Building without Landlord's prior written consent. No drapes,
     blinds, shades, or screens shall be attached to or hung in, or used in
     connection with any window or door of the Premises, without landlord's
     prior written consent. Such awning, projections, curtains, blinds, screens
     or other fixtures must be of a quality, type, design, and color, and
     attached in a manner approved by Landlord.

(c)  Tenant shall keep closed the doors leading to the corridors or main halls
     during business hours except as they may be used to ingress or egress.
     Tenant shall not place any additional locks upon any doors of the Premises,
     nor shall Tenant make any changes in existing locks or the mechanisms
     thereof; except that Tenant may, at its expense, install security locks on
     all entry doors and fire doors opening into the Premises, and also on the
     doors to any offices within the Premises, provided Tenant at the
     termination of its occupancy shall return to Landlord all keys of stores,
     offices, storage and toilet rooms, either furnished to, or otherwise
     procured by Tenant, and in the event of the loss of any keys furnished,
     Tenant shall pay to Landlord the cost to replace. If Landlord requires,
     Tenant shall at its expense remove any additional lock which it installed
     or caused to be installed, reinstall the original hardware, and repair to
     Landlord's satisfaction any damage to doors or frames. Upon request Tenant
     shall give access to any such area(s).

(d)  Tenant shall not construct, maintain, use or operate within the Premises or
     elsewhere in the Building of which the Premises form a part or on the
     outside of the Building, any electrical device, wiring or apparatus in
     connection with a loud speaker system or other sound system unless Tenant
     shall have first obtained Landlord's prior written consent, except that
     this restriction shall not apply to radios, television sets or dictating
     machines, or paging systems, if such items are audible solely within the
     Premises. There shall be no marking, painting, drilling into or in any way
     defacing any part of the Premises or the Building. No Tenant shall throw
     anything out of the doors or windows or down the corridors or stairs.

                                       34

<PAGE>

(e)  Landlord's employees are prohibited from receiving any packages or other
     articles delivered to the Building for Tenant, and should any such employee
     receive any such packages or articles, he or she in so doing shall be agent
     of Tenant and not of landlord.

(f)  Tenant shall not use or permit the use of the water and wash closets and
     other plumbing fixtures for any purposes other than those for which they
     were constructed, and no sweepings, rubbish, rags, or other substances
     shall be thrown therein. All damages resulting from any misuse of the
     fixtures shall be borne by Tenant, whose servants, employees, agents,
     visitors, or licensees shall have caused the same.

(g)  Tenant shall purchase and maintain comprehensive public liability and
     property damage insurance on the Premises, protecting Landlord and Tenant
     against loss, cost, or expense by reason of injury or death to persons or
     damage to or destruction or property by reason of the sue and occupancy of
     the demised premises by Tenant and its invitees, such insurance to be
     carried by reputable companies and having limits of not less than
     $1,000,000 for injury to or death of anyone person, $1,000,000 for each
     accident an $1,000,000 for property damage.

(h)  No vehicles or animals (except guide animals for disabled individuals) of
     any kind shall be brought into or kept in or about the demised premises o
     the Building, an no cooking shall be done or permitted by Tenant on the
     Premises except in kitchens constructed as part of Tenant's Leasehold
     Improvements. NO Tenant shall cause or permit any unusual or objectionable
     odors to be produced upon or emanate form the Premises.

(i)  Neither Tenant, nor any of Tenant's servants, employees, agents, visitors
     or licensees, shall at any time bring or keep upon the Premises any
     flammable, combustible, or explosive fluid, chemical or substance.

(j)  Canvassing, soliciting and peddling in the Building is prohibited and
     Tenant shall cooperate to prevent the same.

(k)  Any person employed by Tenant to do janitorial work within the Premises
     shall obtain Landlord's consent and such person shall, while in the
     Building and outside the Premises, comply with all instructions issued by
     the superintendent of the Building.

(l)  There shall not be used in any space, or in the public hall of the
     Building, either by any Tenant or by jobbers or others, in the delivery or
     receipt of merchandise, any hand trucks, except those equipped with rubber
     tires and side guards.

(m)  Access plates to under floor conduits must be left exposed. Where carpet is
     installed, carpet must be cut around access plates.

(n)  Tenant shall adjust the thermostat, if adjustable, to the setting which
     uses the least amount of energy upon leaving the Premises daily.

(o)  Mats, trash, or other objects are not permitted in the public corridors.

                                       35

<PAGE>

(p)  Landlord and/or its parking contractor shall have the right to establish
     reasonable rules and regulations for the use of all parking facilities at
     the Property.

(q)  Landlord shall have the right to determine when Tenant may move its
     property, i.e., furnishings, files, etc., into or out of ---- the Premises.
     Tenant shall request permission form Landlord's reasonable rules regarding
     any such move.

(r)  Tenant shall not purchase spring water, ice, coffee, sot drinks, towels, or
     other like service, from any company of persons whose repeated violations
     of Building regulations have caused, in Landlord's opinion, a hazard or
     nuisance to the Building and/or its occupants.

(s)  Landlord reserves the right to exclude from him Building at all times any
     person who is not known or does not properly identify himself to the
     Building management or night watchman on duty. Landlord may at its option
     require all persons admitted to or leaving the Building between the hours
     of 6 p.m. and 8 a.m., Monday through Friday, to register. Tenant shall be
     responsible for all persons for whom it authorizes entry into or exist out
     of the Building, and shall be liable to Landlord for all acts of such
     persons.

(t)  The Premises shall not be used for lodging or sleeping or for nay illegal
     purpose.

(u)  Landlord does not maintain suite finishes which are nonstandard, such as
     kitchens, bathrooms, wallpaper, special lights, etc. However, should the
     need for repairs arise, Landlord will arrange for the work to be done at
     Tenant's expense.

(v)  No auction sales shall be conducted in the Building without Landlord's
     consent.

(w)  Tenant shall not use any other method of heating than that provided by
     Landlord without landlord's consent.

(x)  Tenant shall keep window coverings closed at the appropriate time of day to
     prevent direct solar penetration of the Premises.

(y)  Tenant shall purchase and use share mats to protect the carpeting under all
     chairs on casters used in the Premises.

(z)  No freight, furniture or other bulky matter of any description shall be
     received into the Building or carried in the elevators, except at such
     times as approved by Landlord. Tenant shall remove promptly from the public
     area(s) within or adjacent to the Building any of Tenant's personal
     property there delivered or deposited. Landlord shall have the right to
     prescribe the weight, method of installation, and position of safes or
     other heavy fixtures or equipment, shall be repaired at tenant's expense.

(aa) Tenant shall not install o operate in the Premises any electronically
     operated equipment, machinery or appliances, except typewriters, desktop
     computers, adding machines,

                                       36

<PAGE>

     copiers and such other office machinery and equipment as is normally used
     in modern offices, without obtaining landlord's prior written consent which
     consent shall not be unreasonably withheld. Landlord may condition such
     consent upon the payment by Tenant of additional rent in compensation for
     any excess consumption of water and/or electricity as may result form the
     operation of said equipment or machinery. All electricity usage in excess
     of five (5) watts per square foot of net space contained in the Premises,
     as determined by a registered engineer selected by Landlord, shall be
     deemed excess usage for which Tenant shall be charged as additional rent.
     Tenant shall not install any equipment of any kind or nature which shall or
     may necessitate changes, replacements, or additions to, cause an abnormal
     increase in its use of, the water, plumbing, heating, air conditioning or
     electrical systems which serve the Premises, without Landlord's prior
     written consent. Such consent shall not be withheld unreasonably, by may be
     conditioned upon Tenant paying the cost of such changes, replacements,
     additions, or increased use. Notwithstanding the foregoing, if any office
     equipment r mechanical equipment used by Tenant in the Premises shall cause
     noise, or vibration that may transmitted to any part of the Building to
     such degree as to be objectionable to Landlord or any other Tenant, Tenant
     shall install, at its on expense, vibration eliminators or silencing
     devices sufficient to eliminate such noise and/or vibration. Tenant shall
     not install in the Premises any fixtures, equipment, machinery, furniture
     or furnishings which place a load upon the floor exceeding the designed
     floor load capacity.

     Landlord shall advise Tenant in writing of any additions to, deletions
     from, or changes in the foregoing rules and regulations. If Tenant violates
     any Building rule or regulation, Landlord shall notify Tenant in writing of
     the same, and shall allow Tenant a reasonable period of time within which
     to comply with such rule or regulation. Tenant's failure to comply within
     such period of time shall be sufficient cause for termination of this Lease
     at Landlord's sole option.

                                       37

<PAGE>

                                    EXHIBIT D
                      AGREEMENT FOR LEASEHOLD IMPROVEMTENTS
                                FOR OFFICE SPACE

                             TYCON TOWERS I BUILDING

     The parties intend that Tenant shall be permitted freedom in the interior
design and layout of the Premises, consistent with applicable building codes and
with sound architectural and construction practices in first class office
buildings, provided that no interference is caused to the operation of the
Building's mechanical, heating, cooling, or electrical systems or other Building
operations or functions, and no increase in maintenance or utility charges will
be incurred by Landlord. Any additional costs of design, construction,
operation, or maintenance which result from Tenant's deviation from the
quantities or specifications in the Plan shall be charged to Tenant.

A.   Lease Improvements.

     1.   Building standard Improvements. Landlord, at its cost and expense,
shall furnish and install in or for the benefit of the Premises those Leasehold
Improvements set forth in the Plan

     2.   Above-Standard Improvements. All Leasehold Improvements other than
those shown on the Plan that Tenant is required to install in the Premises shall
be at Tenant's sole cost and expense. All such improvements shall comply with
the applicable provisions of the Code of the County of Fairfax,

B.   PLANS AND SPECIFICATIONS.

     1.   Preparation of space Plans and Working Drawings. Tenant may use the
services of the architect and/or space planner retained by Landlord, at no cost
to Tenant, to prepare the Plan and other drawings related to the Plan, or Tenant
may at it own expense employ other professional architectural and/or space
planning assistance. Tenant is responsible for all space planning, architectural
and engineering charges, and the cost of any special permits and other fees in
connection with changes to the Plan requested by Tenant after Landlord's
approval of the Plan.

     Tenant shall devote such time to consult with Landlord's architect and/or
space planner as is necessary to enable the timely preparation of all document
that are a part of the Plan. The Plan shall show partitions, doors, electrical
and telephone outlets, light fixture locations, wall finishes, floor coverings,
and special requirements (if any).

     2.   Schedule for Construction of Leasehold Improvements. At the time of
approval of the Plan, Tenant shall have provide all information necessary to
prepare working drawings and specifications to construct the Leasehold
Improvements to the Premises, including detailed information for any special
requirements such as mechanical and/or electronically systems, hardware, glass,
millwork and finishes. Tenant shall have three (3) business days

                                       38

<PAGE>

following Tenant's receipt of final work drawings to approve and sign off on
said final working drawings and to return the same to Landlord's representative.
Any delay in substantial completion of the Leasehold Improvements due to
Tenant's failure to comply with the time requirements set forth in this Exhibit
D or due to changes to the Plan requested by Tenant, shall be tenant's
responsibility, and Tenant shall not be relieved of its obligations to pay rent
beginning on the date the Premises would have been substantially completed and
tendered to Tenant but for such delay.

C.   CHANGES TO PLAN.

     Tenant is responsible for all architectural and engineering costs and
related design expenses resulting from changes to the Plan requested by Tenant.
After Landlord approves the Plan, no changes to said Plan shall be determined
without landlord's prior written consent. Landlord shall not be responsible for
any delay in occupancy by Tenant as a result of such changes to the Plan, and
Tenant shall be obligated to pay rent commencing on the date the Premises would
have been ready for occupancy in the absence of such changes. Tenant shall,
within three (3) business days following Tenant's receipt of notice of such
cost, notify Landlord in writing whether Tenant desires to proceed with such
change. In the absence of such written authorization by Tenant to proceed with
the change, and payment in full of the total costs of such change, or notice to
omit such change, Landlord shall be entitled to assume such change was not
approved by Tenant an shall proceed with the contraction of the Leasehold
Improvements without the change.

D.   PAYMENT.

     1.   Payment for Architectural and Engineering Costs. Tenant shall pay the
costs of architectural and engineering fees and any special permit or other
charges in connection with changes to the Plan as set forth in subsection 2
below.

     2.   Payment for Tenant's Costs. No later than ten (10) days after receipt
of a bill from landlord, Tenant shall pay Landlord's estimate of any costs to be
paid by Tenant pursuant to this Exhibit D. Tenant shall pay any additional
actual costs within thirty (30) days of receipt of the final bill; if actual
costs are less than estimated costs, Landlord shall refund any excess amounts
paid by Tenant within thirty (30) days of Landlord's receipt of a final bill
from its contractor, unless Tenant is in default under the Lease, in which event
Landlord shall be entitled to apply the excess amount toward payment of any
other monies due to Landlord.

     3.   Failure to Make Timely Payment. If Tenant fails to pay in accordance
with the terms of this Exhibit D, all delinquent sums shall accrue interest at
the rate set forth in subsection (C) of Section 3 of the Lease, commencing on
the date such payment became due.

E.   CONSTRUCTION.

     All work to be done pursuant to this Exhibit D and the Lease, whether
performed at the expense of Tenant or Landlord, shall be performed by Landlord's
designated contractor and coordinated by Landlord's representative.

                                       39

<PAGE>

F.   TENDER OF POSSESSION OF REMISES.

     Following substantial completion of the Premises, and before delivery of
possession, Tenant together with Landlord's designated representative shall make
a final inspection of the Premises to ascertain that the construction has been
substantially completed according to the Plan. A list of items to be completed
or corrected following Tenant's occupancy of the Premises shall be prepared and
signed by all parties. Tenant's obligation to pay rent and to make payments
pursuant to section D (2) above shall not be delayed due to non-substantial
deficiencies.

G.   RESPONSIBILITY FOR DELAYS.

     If Tenant causes any delay in construction the Leasehold Improvements to
the Premises, whether by reason of delays in performance or completion by a
party employed by Tenant, or by reason of building code problems arising form
Tenant's design, or by reason of changes in the work ordered by Tenant after
Landlord's approval of the Plan, then notwithstanding the provisions of the
Lease, or any other provision of this Exhibit D, Tenant's obligation to commence
paying rent shall commence number of days before the date landlord tenders
possession of the substantially completed Premises to Tenant equal to the number
of days delay caused by Tenant and the Lease Commencement Date shall be adjusted
accordingly.

H.   INCORPRATION IN LEASE.

     This Agreement is and shall be incorporated by reference in the Lease and
all of the terms and provisions of said Lese are and shall be incorporated
herein by this reference.

                                       40

<PAGE>

                                    EXHIBIT E
                                PARKING AGREEMENT

     In connection with the Lease to which this Parking Agreement is attached,
Tenant shall be entitled to use certain non-reserved parking spaces in the
parking area(s) adjacent to and/or within the Building, upon the following terms
and conditions.

1.   Landlord hereby grants a license to use, and Tenant is hereby obligated to
     accept fourteen (14) non-reserved parking spaces in the parking area(s)
     adjacent to and/or within the Building (hereinafter referred to as the
     "Parking Facilities").

2.   The license granted hereby shall continue in full force and effect for the
     entire Term of three (3) years, commencing on the Lease Commencement Date
     of expiring on the Lease Expiration Date, or upon the termination of the
     Lease, whichever shall first occur.

3.   This license shall be automatically renewed or extended upon the renewal or
     extension of the Term of the Lease between Landlord and Tenant.

4.   (a)  During and for the entire Term of this License, commencing on the
     Lease Commencement Date, Tenant shall pay to Landlord, or such agent
     designated by Landlord, as rent to use said parking spaces, without
     previous notice of demand therefore, and without deduction, set-off or
     abatement, the total sum of Thirty-Five and 00/100 Dollars ($35.00) per
     parking space per month, until increased as set forth in 4(b) hereof, which
     sum shall be payable in monthly installments, in advance and agreed that
     the cost of such parking spaces, including in Tenants payment of Base Rent
     during the Term of the Lease, but not during renewal or extension thereof.

     (b)  The monthly payments shall be increased on the anniversary of the
          Lease Commencement Date of each year during the Term of this Parking
          Agreement, beginning in 1994, five percent (5%) of the parking fee for
          the immediately preceding month.

     (c)  If Tenant defaults under terms of the Lease, and Landlord exercises
     its option to accelerate the payment of all rent due thereunder, then the
     entire rental payment due under the terms of this parking Agreement shall
     also immediate become due and payable without further notice or demand.

5.   Landlord shall not be liable for damage to any vehicle using the Parking
     Facilities pursuant to this Agreement including theft, collision, fire, or
     any other damage to such vehicle; Landlord shall not be liable for loss of
     use of any such vehicles that are damaged while using the Parking
     Facilities. Tenant shall indemnify the hold Landlord and its agents
     harmless from all loss, damage, liability, cost or expense incurred,
     suffered, or claimed by any person or entity by reason of injury, loss or
     damage to any person, property, or business resulting from Tenant's
     negligence or negligent or unlawful use of the Parking Facilities or
     anything therein.

                                       41

<PAGE>

6.   Tenant shall abide by any reasonable rules and regulations for the use of
     the Parking Facilities which may be adopted by Landlord for the general
     safety, care, cleanliness, and order of the Parking Facilities, the
     Building and Land and the users thereof. Such rules and regulations shall
     be posted in the Parking Facilities and may be changes from time to time as
     Landlord deems necessary.

7.   Tenant my not assign this license to use parking spaces without the prior
     consent of landlord, except in conjunction with a permitted Transfer of the
     Premises.

8.   If Tenant shall fail to make any monetary payment under the terms of this
     Agreement, it shall be default under the terms of the Lease, and Landlord
     shall have all rights and remedies set forth in the Lease, together with
     any further rights under the law.

                                       42

<PAGE>

                                    EXHIBIT F

                           NON-DISTURBANCE, ATTORNMENT
                           AND SUBORDINATOIN AGREEMENT

                             TYCON TOWERS I BUILDING


                                             Dated:  _____________________, 1993


Landlord:  Tycon Tower I Investment Limited Partnership

Tenant:  ______________________________________

Address of Tenant:  ____________________________
                    ____________________________
                    ____________________________

Date of Lease:  ____________________________, 1993

Premises: Te property located at 8000 Towers Crescent Drive, Vienna, Virginia
22182, together with the building thereon

     KEVIN MCALL, JEFFEREY H. STEVENSON, AND J. GRANT MONAHON, AS TRUSTEES OF
AEW #133 TRUST, UNDER DECLARATION OF TRUST DATED AS OF AUGUST 23, 1988, any one
whom may act alone, holder of a deed trust (the "Mortgage") of the Premises and
tenant holder of a lease (the "Lease") of a portion thereof (the "Leased
Premises"), hereby agree as follows:

1.   Provided Tenant is not in default under the terms of the Lease, the right
     of possession of tenant to the Leased Premises, and all other rights of
     Tenant under Lease, shall no be affected or disturbed by Mortgage or any
     note secured thereby, any sale of the Leased Premises pursuant to the
     exercise of any rights and remedies under there Mortgage or otherwise shall
     be made subject to all of Tenant's rights under the Lease.

2.   Tenant shall attorn to Mortgagee o any purchaser of the remises and the
     Lease shall continue, in accordance with its terms, between tenant and
     Mortgagee or such purchaser except that (a) the provisions of the Mortgage
     shall be deemed to survive and govern the disposition of the insurance
     proceeds or condemnation or eminent domain awards and (b) paragraph 3
     thereof shall modify the Lease.

3.   Mortgagee or such purchaser shall not be (a) liable for any act or omission
     of any prior Landlord (including Landlord), (b) liable for the return of
     any security deposit not actually received by Mortgagee or such purchaser,
     (c) subject to any offsets or defenses

                                       43

<PAGE>

     which Tenant might have against any prior landlord (including Landlord),
     (d) bound by any advanced payment of rent made by Tenant to Landlord except
     for rent applicable to the then current month (and except for prepaid rent
     for the first month of the term of the Lease described in Paragraph 3(a)
     thereof), (e) bound by any amendment, modification or termination of the
     Lease made without the written consent of Mortgagee.

4.   The Lease shall be subject and subordinate to the lien of the Mortgage and
     to all the terms, conditions and provisions thereof, to all advances made
     or to be made thereunder, and to any renewals, extensions, modifications or
     replacements thereof, including any increases therein or supplements
     thereto.

5.   The foregoing provisions shall be self-operative. However, Tenant agrees to
     execute and deliver to Mortgagee or to any person to whom Tenant herein
     agrees to attorn such other instrument as either shall reasonably request
     in writing in order to effectuates said provisions.

6.   Tenant certifies that as of the date hereof are no known defaults on the
     pat of Landlord, that the Lease is a complete statement of the agreement of
     the parties thereto with respect to the letting of the Leased Premises.

7.   Tenant will notify Mortgagee at the address set forth below, by registered
     or certified mail, return receipt requested, of any default of Landlord
     which would entitle Tenant to cancel the Lease or abate the rent payable
     thereunder, and agrees that, notwithstanding any provision of the Lease, no
     notice of cancellation thereof, nor any abatement, shall be effective
     against Mortgagee unless Mortgagee has received the notice aforesaid and
     had failed to cure the default within the applicable cure period, if any.

                              c/o Aldrich, Eastman & Waltch, Inc.
                              255 Franklin Street
                              Boston, Massachusetts 02110
                              Attention: J. Grant Monahon, Esquire

                              With copy to:

                              Ballard Spahr Andrews & Ingersoll
                              300 East Lombard Street, Suite 1700
                              Baltimore, Maryland 21202
                              Attention: Fred Wolf, III

8.   Tenant agrees that notice from Mortgagee hall have the same effect under
     the Lease as notice to Tenant form the Landlord thereunder and Tenant
     agrees to be bound by such notice notwithstanding the existence or
     non-existence of a default under the Mortgage or any dispute with respect
     thereto between the mortgagor under the Mortgage and Mortgagee. The
     Landlord has executed this Agreement solely for the purpose of
     acknowledging and consenting to this paragraph 8.

                                       44

<PAGE>

9.   Neither Mortgage nor any purchaser of the Premises, nor any trustee,
     beneficiary, successor or assign thereof shall have any personal liability
     hereunder or with respect to the exercise of the rights and remedies of
     Mortgagee under the Mortgage, and Tenant's sole recourse with respect
     thereto shall be to the equity of Mortgagee or such purchaser in the
     Premises.

10.  This Agreement shall inure to the benefit of and be binding upon the
     parties hereto and their respective successors and assigns, including any
     purchaser of the premises at a foreclosure sale.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
     duly executed as of the day and year first above written.


                                         TENANT:

                                         ---------------------------------------

                                         By:                              (SEAL)
                                             ----------------------------
                                                 Name:
                                                 Title:


                                         MORTGAGEE:

                                         KEVIN MCCALL,  JEFFREY H. STEVENSON
                                         AND J. GRANT MONAHON,  AS TRUSTEES OF
                                         AEW #133 TRUST, UNDER DECLARATION OF
                                         TRUST DATED AS OD AUGUST 23, 1988


                                         By:
                                              ----------------------------------
                                         Name: ___________________________, sole
                                               Acting trustee of AEW #133 Trust,
                                               under Declaration of Trust dated
                                               as of August 23,1988

                                       45

<PAGE>

                                         LANDLORD:

                                         TYCON TOWER I INVESTMENT LIMITED
                                         PARTNERSHIP, a Virginia limited
                                         partnership

                                         By:  TYCON TOWER I  INVESTMENT
                                              CORPORATION,  Virginia
                                              corporation,  its sole general
                                              partner

                                         By:                              (SEAL)
                                              ----------------------------
                                                 Kevin McCall
                                                 Ice President and Director

State of __________________________
County of _________________________

     The foregoing document was acknowledged before me in the above jurisdiction
this __________ day of _____________________________, 1993, by
_____________________________ a _____________________________ of
____________________________.

     My commission expires ________________________________.

                                           -------------------------------------
                                                   Notary Public

State of ___________________________
County of _________________________

     The foregoing document was acknowledged before me in the above jurisdiction
this __________ day of _____________________________, 1993, by
_____________________________, as sole acting trustee of AEW #133 Trust, under
Declaration of Trust dated as of August 23, 1988, and not individually.

     My commission expires ________________________________.


                                           -------------------------------------
                                                   Notary Public

                                       46

<PAGE>

State of ___________________________
County of _________________________

     The foregoing document was acknowledged before me in the above jurisdiction
this __________ day of _____________________________, 1993, by Kevin McCall, as
Vice resident and Director of Tycon Tower I investment Corporation as general
partner of Tycon Tower I Investment Limited, and not individually.

     My commission expires ________________________________.


                                           -------------------------------------
                                                   Notary Public

                                       47

<PAGE>

                              FIRST LEASE AMENDMENT

         THIS FIRST LEASE AMENDMENT (this "Amendment"), is made this ____ day of
_______________, 1995, by and between TYCON TOWER I INVESTMENT LIMITED
PARTNERSHIP, a Virginia limited partnership (the "Landlord"), and ALLIED
RESEARCH CORPORATION, a corporation authorized to do business in the
Commonwealth of Virginia (the "Tenant"),

         WITNESSETH, THAT WHEREAS, by a Lease and Lease Addendum, both dated
April 9, 1993, by and between Landlord and Tenant (collectively, the "Original
Lease" and as further amended the "Lease"), Landlord leased to Tenant and Tenant
leased from Landlord space known as Suite 750 on the seventh (7th) floor of the
building located at 8000 Towers Crescent Drive known as Tycon Tower I (herein
and therein, the "Building") in Vienna, Virginia; and

         WHEREAS, Landlord and Tenant mutually desire to extend the Term of the
Lease as hereinafter set forth,

         NOW, THEREFORE, FOR AND IN CONSIDERATION of the mutual entry into this
Amendment by the parties hereto, and for the other good and valuable
consideration, the receipt and adequacy of which are hereby acknowledged by each
party hereto, the parties hereto hereby covenant and agree as follows:

         Section 1. Amendment of Lease. The provisions of the Lease are hereby
amended in the following manner:

              1.1 Term. The Term of the Lease is hereby extended until September
30, 2000. As of the date hereof, the Lease Expiration Date shall be September
30, 2000.

              1.2 Deletion of Section 53 of the Lease. Section 53 (Option to
Extend) of the Lease is hereby deleted and shall be of no further right to
extend the Term of this Lease unless mutually agreed upon by Landlord and
Tenant.

         Section 2. Definitions. Unless otherwise set forth in this Amendment
all capitalized terms shall have the same meaning as set forth in the Lease.

         Section 3. Effect of this Amendment. Except as is hereinabove set
forth, the provisions of the Lease shall hereafter remain in full force and
effect, as if this Amendment had not been entered into.

         IN WITNESS WHEREOF, each party hereto has executed and ensealed this
Amendment or caused it to be executed and ensealed on its behalf by its duly
authorized representatives, the day and year first above written.

<PAGE>

Witness or ATTEST:              TYCON TOWER I INVESTMENT LIMITED
                                    PARTNERSHIP, a Virginia limited partnership

                                    By:  Tycon Tower I Investment Corporation,
                                         Its sole General Partner


___________________________         By: ______________________________ (Seal)
                                        Thomas K. Albert
                                        Vice President

                                                          Landlord

                                    ALLIED RESEARCH CORPORATION

___________________________         By: ______________________________ (Seal)
                                                    Name:
                                                    Title:

                                                          Tenant

                                       2

<PAGE>

                           NON-DISTURBANCE, ATTORNMENT
                           AND SUBORDINATION AGREEMENT

                             TYCON TOWERS I BUILDING

                                                         Dated: April ____, 1993



Landlord:  Tycon Tower I Investment Limited Partnership

Tenant:    Allied Research Corporation

Address of Tenant:  8000 Towers Crescent Drive
                    Suite 750
                    Vienna, Virginia 22182

Date of Lease:  April ____, 1993

Premises: The property located at 8000 Towers Crescent Drive, Vienna, Virginia
22182, together with the building thereon



         KEVIN MCCALL, JEFFREY H. STEVENSON AND J. GRANT MONAHON, AS TRUSTEES OF
AEW #133 TRUST, UNDER DECLARATION OF TRUST DATED AS OF AUGUST 23, 1988, any one
of whom may at alone, holder of a trust (the "Mortgage") of the Premises and
Tenant, holder of a lease (the "Lease") of a portion thereof (the "Leased
Premises"), hereby agree as follows:

1.       Provided Tenant is not in default under the terms of the Lease, the
         right of possession of Tenant to the Leased Premises, and all other
         rights of Tenant under the Lease, shall not be affected or disturbed by
         Mortgage in the exercise of any of its rights under the Mortgage or
         otherwise shall be made subject to all of Tenant's rights under the
         Lease.

2.       Tenant shall attorn to Mortgagee or any purchaser of the Premises and
         the Lease shall continue, in accordance with its terms, between Tenant
         and Mortgagee or such purchaser except that (a) the provisions of the
         Mortgage shall be deemed to survive and govern the disposition of
         insurance proceeds or condemnation or eminent domain awards and (b)
         paragraph 3 hereof shall modify the Lease.

3.       Mortgagee or such purchaser shall not be (a) liable for any act or
         omission of any prior Landlord (including Landlord), (b) liable for the
         return of any security deposit not actually received by Mortgagee or
         such purchaser, (c) subject to any offsets or defenses which Tenant
         might have against any prior landlord (including Landlord), (d) bound
         by

                                       3

<PAGE>

         any advanced payment of rent made by Tenant to landlord except for rent
         applicable to the ten current month (and except for the prepaid rent
         for the first month of the term of the Lease described in Paragraph
         3(a) thereof), (e) bound by any amendment , modification or termination
         of the Lease made without the written consent of Mortgagee.

4.       The Lease shall be subject and subordinate to the lien of the Mortgage
         and to all the terms, conditions and provisions thereof , to all
         advances made or to be made thereunder, and to any renewals,
         extensions, modification or replacements thereof, including any
         increases therein or supplements thereto.

5.       The foregoing provisions shall be self0operative. However, Tenant
         agrees to execute and deliver to Mortgagee or to any person to whom
         Tenant herein agrees to attorn such other instrument as either shall
         reasonably request in writing in order to effectuate said provisions.

6.       Tenant certifies that as of the date hereof there are no known defaults
         on the pat of Landlord, that the Lease is a complete statement of the
         agreement of the parties thereto with respect to the letting of the
         Leased Premises.

7.       Tenant will notify Mortgagee at the address set forth below, by
         registered or certified mail, return receipt requested, of nay default
         of landlord which would entitle Tenant to cancel the Lease or abate the
         rent payable thereunder, and agrees that, notwithstanding any
         provision, of the Lease, no notice of cancellation thereof, nor any
         abatement, shall be effective against Mortgagee unless Mortgagee has
         received the notice aforesaid and has failed to cure the default within
         the applicable cure period, if any.

                            C/o Aldrich, Eastman & Watch, Inc.
                            255 Franklin Street
                            Boston, Massachusetts 02110
                            Attention:  J. Grant Monahan, Esquire

                            With copy to:
                            Ballard Spahr Andrews & Ingersoll
                            300 East Lombard Street, Suite 1700
                            Baltimore, Maryland 21202
                            Attention:  Fred Wolf, III

8.       Tenant agrees that notice from Mortgagee shall have the same effect
         under the Lease as notice to Tenant form the Landlord thereunder and
         Tenant agrees to be bound by such notice notwithstanding the existence
         or non-existence of a default under the Mortgage or any dispute with
         respect thereto between the mortgagor under the Mortgage and mortgagee.

9.       Neither Mortgagee nor any purchaser of the Premises, nor any trustee,
         beneficiary, successor or assign thereof shall have any personal
         liability hereunder or with respect to the exercise of the rights and
         remedies of Mortgagee under the Mortgage, and Tenant's


                                       4

<PAGE>

         sole recourse with respect thereto shall be to the equity of Mortgagee
         or such purchaser in the Premises.

10.      This Agreement shall inure to the benefit of and be binding upon the
         parties hereto and their respective successors and assigns, including
         any purchaser of the premises at a foreclosure sale.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
         duly executed as of the day and year first above written.

                           TENANT:

                           ALLIED RESEARCH CORPORATION

                           By: ____________________________ (SEAL)
                               Name:
                               Title:



                           MORTGAGEE:

                           KEVIN MCCALL,  JEFFREY H. STEVENSON
                           AND J. GRANT MONAHON,  AS TRUSTEES OF
                           AEW #133 TRUST, UNDER DECLARATION OF
                           TRUST DATED AS OF AUGUST 23,1988


                           By: ___________________________________
                           Name:_____________________________, sole
                                Acting trustee of AEW #133 Trust, under
                                Declaration of Trust dated as of
                                August 23,1988

                           LANDLORD:

                           TYCON TOWER I INVESTMENT LIMITED
                           PARTNERSIP, a Virginia Limited partnership

                           By:  Tycon Tower I Investment Corporation, a
                                Virginia corporation, its sole general partner

                           By: ____________________________ (SEAL)
                               Kevin McCall
                               Vice President and Director

                                       5

<PAGE>

State of ________________________
County of ______________________

         The forgoing document was acknowledged before me in the above
jurisdiction this ______ day of ____________, 1993, by ____________________ a
_________________ of Allied Research Corporation.

         My commission expires _______________________.



                                 ________________________________________
                                               Notary Public

State of ________________________
County of ______________________

         The foregoing document was acknowledged before me in the above
jurisdiction the _________ day of __________________, 1993, by
___________________________, as sole acting trustee of AEW #133 Trust, under
Declaration of Trust dated as of August 23, 1988, and not individually.

         My commission expires ___________________________.



                                 ________________________________________
                                               Notary Public

State of:  _______________________
County of:______________________

         The foregoing document was acknowledged before me in the above
jurisdiction the ______ day of ______________________, 1993, by Kevin McCall, as
Vice President and Director of Tycon Tower I Investment Corporation as general
partner of Tycon Tower I Investment Limited, and not individually.

         My commission expires ____________________________.

                                 ________________________________________
                                               Notary Public

                                       6


<PAGE>

                                 LEASE ADDENDUM

         THIS ADDENDUM TO LEASE, made this _________ day of _____________, 1993,
by and between TYCON TOWER INVESTMENT LIMITED PARTNERSHIP, a Virginia limited
partnership, as Landlord, and ALLIED RESEARCH CORPORATION, a corporation
authorized to do business in the Commonwealth of Virginia, as Tenant, for space
in the Tycon Tower I Building located at 8000 Towers Crescent Drive, Vienna,
Virginia, is attached to and made a part of that certain Standard Office Lease
of even date between Landlord and Tenant (the "Lease"), and sets forth
additional terms agreed upon by Landlord and Tenant. If any conflict exists
between the provisions of this Lease Addendum and any provisions of the Lease,
the provisions of this Lease addendum shall control.

         1. Amending Section 4(a). Kandlord hereby agrees tat the actual cost of
controllable Operating Expenses in any calendar year during the Term shall not
exceed seven percent (7%) of such actual controllable Operating Expenses for the
immediately preceding calendar year.

         2. Amending Section 8(a). Notwithstanding any provision of this section
8(a) or this Lease to the contrary, Landlord hereby agrees that Tenant may
assign all of Tenant's rights, title and interest in and to this Lease, or
sublet the Premises or any portion thereof, to any corporation, partnership, or
entity to which Tenant may assign or sublet this Lease pursuant to the forgoing
provision must have a total net worth equal to or greater than that of Tenant at
the time Tenant executed this Lease. Tenant shall deliver to Landlord the name,
address and current financial statement of such assignee or sublease at least
thirty (30) days prior to effectuating such assignment or sublet.

         3. Amending Section 8(b). In the event that Landlord permits Tenant to
sublease any portion of the Premises, Tenant shall pay landlord fifty percent
(50%) of any excess of any rent accruing to Tenant; provided however, Tenant
incurs in subleasing such space, limited to reasonable advertising costs,
expenses incurred in subleasing such space, and reasonable brokerage
commissioned, before arriving at the net excess rent to be shred with Landlord
pursuant to this paragraph. Tenant shall provide documentation of such expenses
prior to Landlord giving its written consent for subletting.

         4. Amending Section 11(d). Notwithstanding any provision of this
section 11(d) to the contrary, Tenant shall be permitted to remove any
Alterations paid for and installed by tenant restores any and all damage to the
Premises occasioned thereby, ordinary war and tear excepted.

         5. Amending Section 27. In lieu of a cash Security Deposit, tenant may,
upon the execution of this Lease by Tenant, deliver to Landlord an unconditional
and irrevocable Letter of Credit from an area banking institution approved by
Landlord as security for the Security Deposit to be held by Landlord as security
for the performance by Tenant of all the covenants and obligations of Tenant set
forth in the Lease. Said Letter of Credit shall contain terms whereby it can be
drawn on by Landlord at sight on any date during the term of the Lease on which
issuer shall receive from landlord a certification signed by Landlord stating
that Tenant is

                                       7

<PAGE>

in default, after applicable cure periods, under the terms of the Lease. Any
balance left of the sum received form drawing on the Letter of Credit, after the
correction of defaults by Tenant and/or the payment of amounts due by Tenant,
Tenant shall replace same no later than thirty (30) days after the date of such
drawing, and if same is not replaced it shall constitute a default under the
terms of the Lease and Landlord shall have the benefit of all remedies permitted
pursuant to the terms of the Lease and the laws of the State f Virginia.

         Upon the sale o transfer of Landlord's interest in the Building,
Landlord shall transfer the Letter of Credit to such purchaser or transferee, in
which event Tenant shall only look to the new landlord for the return of the
Letter of Credit and Landlord shall thereupon be released from all liability to
Tenant for the return of such Letter of Credit provided such purchaser or
transferee agrees to be liable for the return of the Letter of Credit pursuant
to the terms of this Lease.

         6. Section 50. Improvement Allowance. Landlord hereby agrees to provide
Tenant with an Improvement Allowance in the amount equal to Seven Dollars
($7.00) per rentable square foot of space in the premises to be applied to the
construction of the Leasehold Improvements (the "Improvement Allowance").

         7. Section 51. relocation Allowance. Provided Tenant is not in default
hereunder, Tenant shall be entitled to be reimbursed for any and all costs
associated with Tenant's move to the Premises in an amount not to exceed One
Dollar ($1.00) per rentable square foot of space in the Premises (the
"Relocation Allowance"). Bills for such costs shall be submitted to Landlord's
representative within sixty (60) days following the Lease Commencement Date and
shall be reimbursed within thirty (30) days submittal.

         8. Section 53. Option to Extend.

                  (i)      Tenant shall have the option to extend this Lease for
                           one (1) term of three (3) years (hereinafter referred
                           to as the "Renewal term") provided that Tenant is not
                           in default pursuant to any of the terms of the Lease
                           at the time of commencement of the Renewal Term.

                  (ii)     The Renewal Term shall be upon the same terms,
                           covenants and conditions as provided in this Lease,
                           except that the not be entitled to any of the
                           allowances, credits or payments provided in this
                           Lease, and that the Base Years shall be adjusted to
                           the first year of the Renewal Term.

                  (iii)    The Base Rent at the commencement of the Renewal Term
                           shall be ninety-five percent (95%) of the prevailing
                           market rate for the Washington, D.C. metropolitan
                           are. In no event, however, shall the prevailing
                           market rate be less than the aggregate amount of the
                           Base rent and Tenant's share of increases in
                           Operating Expenses reserved under the Lease for the
                           year immediately preceding the Renewal Term.

                  (iv)     Such option to extend shall be exercised by Tenant
                           giving written notice to Landlord not later than nine
                           (9) months prier to the expiration of the original
                           term. Landlord shall within thirty (30) days of the
                           date it receives notice of Tenants election to
                           exercise its option to extend, notify Tenant of the
                           Base Rent to be charged at the commencement o the
                           Renewal Term. Tenant shall have thirty (30) days form
                           the date of the Landlord's

                                       8

<PAGE>

                           notification of the Base Rent to be charged to
                           nullify its exercise of the option by providing
                           Landlord written notice of the same. If Tenant
                           nullifies its exercise of this option to extend, this
                           option shall terminate and be of no further force and
                           effect.

                  (v)      Tenant agrees to accept the Premises in the condition
                           then existing as of the date of the commencement of
                           the Renewal Term. Landlord shall not be responsible
                           for performing any work, furnishing any materials or
                           providing any allowances for improvements to the
                           Premises, except as mutually agreed upon by Landlord
                           and Tenant.

         9. Section 54. Tower Club Membership. If accepted for membership,
Landlord shall pay the initiation fees in the Tower Club on the 17th floor of
the Building for one (1) corporate membership designating up to two (2)
individual executives of Tenant. Tenant shall be responsible for all other fees,
including monthly membership fees, associated with such membership. Landlord
makes no representations or commitment as to continued operation of said Tower
Club throughout the Term of this Lease.

         10. Section 55. Security. The Building had a first-class electronic
access and monitoring system provided at Landlord's expense. Such security
system shall not be deemed to insure the safety of Tenant, its employees, agents
or invites, or their property, and Landlord shall not be liable for damage or
injury caused by the criminal act of third parties occurring in the Premises,
the Building or on the Property.

         11. Section 56. Entry Door Signage. Landlord shall provide Tenant with
the building-standard signage at the entrance to Tenants suite. Tenant shall be
permitted to install within the Premises its own signage, the design, location
and size of which shall be approved by Landlord prior to installation. Tenant
shall be responsible for the cost of Tenants' signage within the Premises, but
Landlord hereby agrees to provide Tenant with a credit equal to the cost of the
building-standard sign.

         12. Section 57. Pre-Lease Commencement Date Access. Landlord hereby
agrees to give Tenant prior notice of the date that Landlord anticipates the
Premises will be ready for tenant's occupancy. Notwithstanding any provisions to
the contrary in Sectoin6, provided such work by Tenant or tenant's contractors
does not interfere with Landlord's construction work, Tenant shall have the
right to enter the Premises within seven (7) days prior to the Lease
Commencement Date to make Tenant installations, without liability for rent
during such period, but subject to all of the terms, covenants, conditions and
provisions of this Lease.

         WITNESSETH the following signatures and seals:

                                  LANDLORD:

                                  TYCON TOWER I INVESTMENT LIMITED
                                  PARTNERSHIP, a Virginia limited partnership


                                       9

<PAGE>

                                      By:  TYCON TOWER I INVESTMENT
                                           CORPORATION, a Virginia corporation,
                                           its sole general partner




Date: ________________, 1993          By: ____________________________ (SEAL)
                                          Name:  Kevin McCall
                                          Title: Vice President


                                      TENANT:

                                      ALLIED RESEARCH CORPORATION

Date: ________________, 1993          By: _____________________________(SEAL)
                                          Name:
                                          Title:

                                       10

<PAGE>

                            SECOND AMENDMENT TO LEASE

         THIS SECOND AMENDMENT TO LEASE (this "Second Amendment"), is made this
_____ day of ______________, 1999, by and between TYCON TOWER I INVESTMENT
LIMITED PARTNERSHIP, a Virginia limited partnership ("Landlord"), and ALLIED
RESEARCH CORPORATION, a corporation authorized to transact business in the
Commonwealth of Virginia ("Tenant").

                                   WITNESSETH:

         WHEREAS, Landlord and Tenant have previously entered into that certain
Standard Office Lease and Lease Addendum, each dated April 9, 1993 (the
"Original Lease"), by the terms of which Landlord leased to Tenant and Tenant
rented from Landlord Suite 750 consisting of approximately 4,341 rentable square
feet of space on the seventh floor of the Building which is located at 8000
Towers Crescent Drive, Vienna, Virginia known as Tycon Tower I (the "Original
Premises");

         WHEREAS, the Original Lease was amended by that certain First Lease
Amendment dated March 9, 1993 (the "First Amendment"), by the terms of which
Landlord and Tenant agreed to extend the term of the Lease; and

         WHEREAS, Landlord and Tenant mutually desire by this Second Amendment
to amend the Lease to provide for the relocation of Tenant from the Original
Premises to the New Premises (as hereinafter defined) and to amend certain other
provisions of the Lease as hereinafter set forth (the Original Lease, as amended
by the First Amendment and this Second Amendment being referred to herein as the
"Lease").

         NOW, THEREFORE, FOR AND IN CONSIDERATION of the mutual entry into this
Second Amendment by Landlord and Tenant, and for other good and valuable
consideration, the receipt and adequacy of which are hereby acknowledged by each
to the other, Landlord and Tenant hereby covenant and agree as follows:

         Section 1. Defined Terms. Unless otherwise set forth in this Second
Amendment, all capitalized terms shall have the same meanings as set forth in
the Original Lease.

         Section 2. Amendment of Lease. The provisions of the Original Lease are
hereby amended in the following manner:

              (a) New Commencement Date. The term "New Commencement Date" means
the earlier of (i) February 1, 2000, or (ii) the date on which the New Premises
are substantially complete.

              (b) Relocation of Premises. From and after the New Commencement
Date, the Tenant shall relocate from the Original Premises to the space known as
Suite 260 on the second (2nd) floor of the Building and containing an area of
3,879 rentable square feet as shown

<PAGE>

on the floor plan attached hereto and incorporated herein as Exhibit A
(hereinafter referred to as the "New Premises"). Said square footage has been
calculated in accordance with the WDCAR Standard Method of Measurement (Revised
1989). Effective on the New Commencement Date, Tenant shall have no right to
occupy or use the Original Premises and shall immediately surrender possession
of the Original Premises to Landlord in accordance with the provisions of the
Lease.

              (c) Premises. Effective on the New Commencement Date, all
references to the "Premises" contained in the Lease shall mean the New Premises.

              (d) Term. Effective on the New Commencement Date, the Term of the
Lease shall be seven (7) years and shall terminate at 12:00 Midnight on the last
day of the eighty-fourth (84th) full calendar month following the New
Commencement Date (the "Lease Expiration Date"; the period of time from the New
Commencement Date until the Lease Expiration Date is hereinafter referred to as
the "New Term"). Effective on the New Commencement Date, all references to the
"Term" contained in the Lease shall mean the New Term.

              (e) Rent.

                  (i) Base Rent. Effective on October 1, 2000, the Base Rent
shall be amended to be the sum of Thirty-One and 50/100 Dollars ($31.50) per
square foot of rentable area contained in the New Premises or One Hundred
Twenty-Two Thousand One Hundred Eighty-Eight and 50/100 Dollars ($122,188.50)
per annum, payable in equal monthly installments, in advance, of Ten Thousand
One Hundred Eighty-Two and 40/100 Dollars ($10,182.40) and adjusted thereafter
annually in accordance with Section 3(b) of the Lease. From the New Commencement
Date until October 1, 2000, Tenant shall pay for the New Premises the current
Monthly Base Rent escalated in accordance with the terms of the Lease.

                  (ii) Square Footage Calculations. Effective on the New
Commencement Date, the number of square feet of rentable area contained in the
Premises for purposes of Section 3 of the Lease shall be amended to be 3,879.

              (f) Operating Expenses and Real Estate Taxes.

                  (i) Payments. Notwithstanding any provision of Section 4(a) of
the Lease to the contrary, effective on the New Commencement Date, the Base Year
shall be calendar year 2000.

                  (ii) Proportionate Share. Effective on the New Commencement
Date, Section 4(d) of the Lease shall be amended by deleting the number
"416,754" therefrom and inserting in lieu thereof the number "403,684".

                  (iii) Square Footage Calculations. Effective on the New
Commencement Date, the number of square feet of rentable area contained in the
Premises for the purposes of Section 4 of the Lease shall be amended to 3,879.

                                       2

<PAGE>

              (g) Preparation of New Premises for Tenant's Occupancy. Landlord
shall paint the reception wall behind Tenant's sign of the New Premises at its
sole cost and expense. Except for the foregoing, tenant agrees to accept the New
Premises in its "AS IS" condition.

              (h) Parking. Effective on the New Commencement Date, Tenant agrees
that it is granted a license for two (2) reserved parking spaces in the Parking
Facilities which shall be located in the parking garage in a location mutually
acceptable to Landlord and Tenant and ten (10) non-reserved parking spaces with
the lease of the New Premises. Notwithstanding anything in Section 4 of Exhibit
E of the Lease to the contrary, the rent for the parking spaces shall be
included in the Base Rent during the New Term, but not during the Renewal Term,
if any.

         Section 3. Option to Extend.


              (a) Tenant shall have the option to extend the Lease for one (1)
term of five (5) years (the "Renewal Term") provided that this Lease is in full
force and effect, Tenant is in occupancy, and Tenant is not in default pursuant
to any of the terms of the Lease at the time of the exercise of this option to
extend or at the time of commencement of the Renewal Term. The option granted
herein shall no be severed from this Lease, or separated, sold or assigned in
connection with an acquisition, merger, or change of form of organization of
Tenant if (i) notice is provided to Landlord in accordance with Section 8(b) of
the Lease, (ii) approval of said new entity by Landlord is obtained in
accordance with Section 8 of the Lease, and (iii) Tenant remains primarily
liable under the Lease.

              (b) The Renewal Term shall be upon the same terms, covenants and
conditions as provided in this Lease, except that the Base Rent shall be
adjusted as hereinafter provided, the Tenant shall not be entitled to any of the
allowances, credits or payments provided in this Lease, and the Base Year shall
be adjusted to the first year of the Renewal Term. Tenant shall have no further
right to renew.

              (c) The Base Rent at the commencement of the Renewal Term shall be
the greater of (i) the prevailing market rate for similar office buildings in
the Tysons Corner, Virginia area or (ii) the Base Rent in effect immediately
before the Lease Expiration Date. The determination of the prevailing market
rate shall be determined in good faith by Landlord based on similar first-class
buildings in the Northern Virginia metropolitan area and shall take in to
account (i) tenant improvement allowances and other rental concessions, (ii) the
condition of the Premises, and (iii) the condition of the space with which the
Premises are being compared.

              (d) Such option to extend shall be exercised by Tenant giving
written notice to Landlord not less than twelve (12) and no more than fifteen
(15) months prior to the Lease Expiration Date. Landlord shall within twenty
(20) days of the date it receives notice of Tenant's election to exercise its
option to extend, notify Tenant of the Base Rent to be charged at the
commencement of the Renewal Term. Tenant shall have ten (10) days from the date
of the Landlord's notification of the Base Rent to be charged to nullify its
exercise of the option by providing Landlord written notice of the same. If
tenant nullifies its exercise of this option to extend, this option shall
terminate and be of no further force and effect.

                                       3

<PAGE>

              (e) Tenant agrees to accept the Premises in the condition then
existing as of the date of the commencement of the Renewal Term. Landlord shall
not be responsible for performing any work, furnishing any materials or
providing nay allowances for improvements to the Premises, except as mutually
agreed upon by the Landlord and Tenant.

         Section 4. [Intentionally deleted]

         Section 5. Condition Precedent. The rights and obligations of Landlord
and Tenant hereunder are contingent upon Landlord leasing the Original Premises
to a new tenant at prevailing market rates on or before November 15, 1999. If
this condition precedent is not satisfied by the date specified, this second
Amendment shall be null and void and the Lease between landlord and Tenant shall
continue in full force and effect as if this Second Amendment had never been
signed.

         Section 6. Brokers. Landlord and Tenant agree that Grubb & Ellis is the
only broker under this Second Amendment. Landlord is solely responsible for any
commissions due to said brokers as a result of this Second Amendment.

         Section 7. Full Force and Effect. The Lease is hereby reaffirmed and
all of the terms, covenants and conditions of the Lease shall remain the same
and continue in full force and effect and shall be deemed unchanged, except as
such terms covenants and conditions of the Lease have been amended or modified
by this Second Amendment, and this Second Amendment shall, by this reference,
constitute a part of the Lease.

                                       4

<PAGE>

         IN WITNESS WHEREOF, each party hereto has executed and ensealed this
Amendment or caused it to be executed and ensealed on its behalf by its duly
authorized representatives, the day and year first above written.

WITNESS OR ATTEST:                  LANDLORD:

                                    TYCON TOWERS I INVESTMENT LIMITED
                                    PARTNERSHIP, a Virginia limited partnership

                                    By: Tycon Tower I Investment
                                        Corporation, its sole General Partner

______________________________      By:  _________________________(Seal)
                                         Name:  Thomas K. Albert
                                         Title:  Vice President


                                    TENANT:
                                    ALLIED RESEARCH CORPORATION

_______________________________     By:  ______________________________(Seal)
                                         Name:  William Glenn Yarborough, Jr.
                                         Title:   President

                                       5

<PAGE>

                            SECOND AMENDMENT TO LEASE

                                    EXHIBIT A

                           Floor Plan of New Premises


                                       6