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                                                                     EXHIBIT 4.2

                               FIRST AMENDMENT TO
                    ALION SCIENCE AND TECHNOLOGY CORPORATION
                 EMPLOYEE OWNERSHIP, SAVINGS AND INVESTMENT PLAN


         WHEREAS, Alion Science and Technology Corporation (the "Company")
maintains an Employee Ownership, Savings and Investment Plan for the benefit of
its Employees and the Employees of any other Adopting Employer, which Plan was
last amended and restated as of December 19, 2001 (the "Plan); and

         WHEREAS, under Section 15.1 of the Plan, the Company reserved the right
to amend the Plan at any time, in whole or in part, by action of its Board of
Directors; and

         WHEREAS, the Board of Directors of the Company, pursuant to Section
15.1 of the Plan, has delegated authority to amend the Plan to the undersigned
officer, provided he determines that the amendment would not materially increase
costs of the Plan to the Company or any Adopting Employer; and

         WHEREAS, the undersigned officer has determined that this First
Amendment would not materially increase costs of the Plan to the Company or any
Adopting Employer;

         NOW, THEREFORE, pursuant to the powers of amendment reserved under
Section 15.1 of the Plan, the Plan is hereby amended by the Company, effective
October 1, 2002, unless otherwise provided, as follows:


                                   ARTICLE II

Section 2.33 - Amended by striking the same (except for the heading) and
substituting in lieu thereof the following:

                  "An Eligible Employee who (a) is or was an employee of IIT
         Research Institute and became an Employee of an Adopting Employer in
         the first Plan Year, or (b) was an employee of IIT Research Institute
         on or before December 20, 2002 and became an Employee of an Adopting
         Employer within five (5) years of the Employee's termination of
         employment with IIT Research Institute."

Section 2.48 - Amended by striking the first sentence and substituting in lieu
thereof the following:

                  "That portion of a Period of Service during which an Eligible
         Employee was a Participant."

Section 2.49 - Effective December 19, 2001, amended by adding between the first
and second sentences the following:


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         "If the Severance from Service is because the Employee resigns, retires
         or is discharged, and the Employee is rehired by an Employer within
         twelve (12) months after his Severance from Service Date, the period
         between his Severance from Service Date and his rehire date is included
         in his Period of Service. Notwithstanding the foregoing, if an Employee
         resigns, retires or is discharged during a period of absence for any
         reason other than a resignation, retirement, discharge or death, the
         period between his Severance from Service Date and his rehire date is
         included in his Period of Service only if the Employee's rehire date is
         within twelve (12) months after the original absence date."

Section 2.51 - Effective December 19, 2001, amended by striking the same (except
for the heading) and substituting in lieu thereof the following:

                  "The Alion Science and Technology Corporation Employee
         Ownership, Savings and Investment Plan, as amended from time to time."


                                   ARTICLE III

Section 3.1 - Amended by striking the second sentence and substituting in lieu
thereof the following:

         "An Eligible Employee shall be eligible for a Matching Contribution,
         and Profit Sharing Contribution, if any, immediately following his or
         her completion of a Period of Service of twelve (12) consecutive
         months."

Further amended by adding at the end thereof the following:

         "An Eligible Employee who was eligible for a Matching Contribution, and
         Profit Sharing Contribution, if any, as of the date he or she incurred
         a Severance from Service, and who is reemployed as an Eligible
         Employee, shall again be eligible for a Matching Contribution, and
         Profit Sharing Contribution, if any, immediately following his or her
         date of reemployment."


                                   ARTICLE IV

Section 4.3 - Amended by striking the second sentence and substituting in lieu
thereof the following:

         "For the Plan Year beginning October 1, 2002, the Board of Directors
         has authorized a Profit Sharing Contribution of 2.5% of the
         Compensation of all Participants eligible to share in the Profit
         Sharing Contribution for that Plan Year, 1% to the ESOP Component and
         1.5% to the Non ESOP Component."


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Further amended by striking "Total Compensation" in the fourth sentence and
substituting in lieu thereof "total Compensation".

Further amended by adding between the fourth and fifth sentences the following:

         "For purposes of the second and fourth sentences of this Section 4.3,
         the Compensation of a Participant who during the Plan Year first
         becomes eligible under Section 3.1 to share in the Profit Sharing
         Contribution shall only include amounts paid on or after said date."

Section 4.4(a) - Amended by striking the last sentence and substituting in lieu
thereof the following:

         "This Matching Contribution shall be determined each Plan Year based on
         the Compensation and total pre-tax deferrals for the Plan Year.
         Notwithstanding the foregoing, the Compensation and pre-tax deferrals
         of a Participant who during the Plan Year first becomes eligible under
         Section 3.1 to receive a Matching Contribution shall only include
         Compensation paid and pre-tax deferrals made on or after said date."

Section 4.9 - Amended by striking the next to last paragraph.

Further amended by striking the last paragraph and substituting in lieu thereof
the following:

                  "For so long as the Plan satisfies the aforesaid safe harbor
         requirements, the testing requirements of this Section 4.9 shall not
         apply to those Eligible Participants entitled to receive a Matching
         Contribution described in Section 4.4."


                                    ARTICLE V

Section 5.1(d) - Amended by adding "or a rehired Employee" at the end of the
first sentence thereof.

Section 5.11(a) - Amended by striking "Participants' ESOP Profit Sharing
Accounts" and substituting in lieu thereof "Participants' ESOP Accounts".

Section 5.11(c) - Amended by adding "cash" before "dividends" in the first line.

                                   ARTICLE VII

Section 7.2(a) - Amended by striking "Profit Sharing Contribution Accounts" and
substituting in lieu thereof "ESOP Profit Sharing Account and Non ESOP Profit
Sharing Account".


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Section 7.3(a) - Amended by striking the first sentence and substituting in lieu
thereof the following:

                  "In the event that a Participant incurs a Severance from
         Service before attaining a nonforfeitable right to his or her entire
         ESOP Profit Sharing Account, the portion of his or her ESOP Profit
         Sharing Account that is forfeitable will be forfeited as of the first
         day of the month immediately following the earlier of: (1) the date on
         which the Participant incurs a Period of Severance of five (5)
         consecutive years; or (2) the date on which the vested portion of the
         Participant's ESOP Profit Sharing Account is distributed in accordance
         with ARTICLE IX. In the event that a Participant incurs a Severance
         from Service before attaining a nonforfeitable right to his or her
         entire Non ESOP Profit Sharing Account, the portion of his or her Non
         ESOP Profit Sharing Account that is forfeitable will be forfeited as of
         the first day of the month immediately following the earlier of: (A)
         the date on which the Participant incurs a Period of Severance of five
         (5) consecutive years; or (B) the date on which the vested portion of
         the Participant's Non ESOP Profit Sharing Account is distributed in
         accordance with ARTICLE IX."

Further amended by striking the last sentence and substituting in lieu thereof
the following:

         "Forfeitures from the ESOP Component of the Plan will be reallocated as
         of the next Allocation Date to Participants who are eligible to receive
         a Profit Sharing Contribution for the Plan Year in the same manner as
         Profit Sharing Contributions are allocated to Participants under
         Section 4.3."

Section 7.4(b) - Effective December 19, 2001, amended by striking "Hour of
Service is credited" and substituting in lieu thereof "Hour of Service is not
credited".


                                  ARTICLE VIII

Section 8.1(a) - Effective December 19, 2001, amended by striking subsection
(a)(3) and substituting in lieu thereof the following:

         "(3) ESOP and Non ESOP Elective Deferral Accounts (excluding earnings
         on Elective Deferrals) in the event of a hardship."



                                   ARTICLE IX

Section 9.1(b) - Effective December 19, 2001, amended by striking "401(a)(4) and
401(a)(9)" in the first sentence and substituting in lieu thereof "401(a)(9) and
401(a)(14)".


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                                   ARTICLE X

Section 10.6 - Amended by striking "10.2 or 10.5" in the last sentence and
substituting in lieu thereof "10.2, 10.5, 10.7 or 10.8".


                                    Exhibit A

Effective December 19, 2001, amended by adding the following below the heading
in Exhibit A:

                               "Adopting Employers

Name                                                  Effective Date of Adoption
Alion Science and Technology
   Corporation                                        December 19, 2001
Human Factors Applications, Inc.                      December 20, 2002".


                                    Exhibit C

Amended by striking "Prior Year Method" and substituting in lieu thereof
"Current Year Method".


                                   In General

         Any provision of the amended and restated Plan inconsistent with the
         foregoing changes is hereby amended to be consistent herewith.


         IN WITNESS WHEREOF, Alion Science and Technology Corporation has caused
this First Amendment to the Plan to be executed on its behalf by its duly
authorized officer on this 20th day of March, 2003.


                                        ALION SCIENCE AND TECHNOLOGY CORPORATION

                                        By: /s/ BAHMAN ATEFI
                                            ------------------------------------
                                        Title: Chief Executive Officer
                                               ---------------------------------

                                                         (Seal)



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