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                                                                    EXHIBIT 10.9

 
                             WHITTAKER CORPORATION
                              EXCESS BENEFIT PLAN
                              -------------------


     This Excess Benefit Plan (hereinafter referred to as the "Plan") has been 
adopted by the Board of Directors of Whittaker Corporation, a Delaware 
corporation (hereinafter referred to as the "Company"), effective as of January 
1, 1988.

     1.  Prior Plan
         ----------

         This Plan amends, restates and supercedes the provisions of the 
Whittaker Corporation Supplemental Benefit Plan effective September 1, 1982, 
relating to the payment of benefits to certain participants of the Whittaker 
Corporation Employees' Pension Plan whose benefits under such Plan are reduced 
because of the limitations under Code Section 415 (the "Prior Plan").  The 
provisions of this Plan shall only apply to (a) participants in the Prior Plan 
whose benefits under such Prior Plan were not in pay status on January 1, 1988, 
and (b) individuals who become eligible to participate herein on or after 
January 1, 1988.

     2.  Purpose
         -------

         The purpose of the Plan is to provide additional retirement income for
certain Employees who participate in the Whittaker Corporation Employees'
Pension Plan whose retirement benefits are reduced because of the limitations
under Code Section 415.

     3.  Definitions
         -----------

         The following definitions, set forth in alphabetical order, are used 
throughout the Plan.  Terms or phrases appearing in capital letters that ar not 
defined below shall have the same meanings as under the Retirement Plan, as 
defined below.

         (a)  "Board of Directors" means the Board of Directors of the Company.

         (b)  "Code" means the Internal Revenue Code of 1986, as amended and in 
effect from time to time.

         (c)  "Committee" means the Compensation and Stock Option Committee of 
the Board of Directors.

         (d)  "Excess Benefit" means the benefit described in Section 5.

                                      -1-

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           (e) "Participant" means an executive officer of Whittaker Corporation
who satisfies the conditions for eligibility described in Section 4. The term
"Participant" shall also include the Beneficiary of a deceased Participant.

           (f) "Retirement Plan" means the Whittaker Corporation Employees'
Pension Plan, as amended from time to time, which is a defined benefit pension
plan qualified under Section 401(a) of the Code.

     4.   Eligibility to Participate
          --------------------------

          Each Participant whose aggregate pension benefit under the Retirement
Plan and any other defined benefit pension of an Affiliated Company is reduced
by reason of the maximum benefit limitations of Code Section 415 shall become a
Participant in the Plan.

     5.   Excess Benefits
          ---------------

          (a)  Amount of Benefits
               ------------------

               Each Participant shall be entitled to an Excess Benefit under
this Plan in an amount equal to the actuarial equivalent of the difference
between (i) and (ii), where:

               (i)  equals the aggregate amount of monthly pension benefit
payable to the Participant under the Retirement Plan and any other defined
benefit pension plan of an Affiliated Company on the normal benefit commencement
date specified in the Retirement Plan and such other defined benefit pension
plan, as determined under the normal retirement benefit formula of the
Retirement Plan and such other defined benefit pension plan before applying any
provision of the Plan that would reduce benefits because of the maximum benefit
limitations under Code Section 415; and

               (ii) equals the aggregate amount of a Participant's monthly
pension benefit determined in paragraph (i) above after applying the maximum
benefit limitations under Code Section 415.

          (b)  Form of Benefits
               ----------------

               The Excess Benefit determined in subsection (a) above shall be
paid to the Participant in the form of a monthly, straight-life annuity.  The
amount of such annuity shall be determined by the actuary for the Retirement
Plan using the actuarial assumptions set forth in the Retirement Plan for
purposes of determining the actuarial equivalent of alternative forms of
benefits.

                                      -2-
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     6.   Vesting
          -------

          Subject to the rights of general creditors as set forth in Section 8
and the right of the Company to discontinue the Plan as provided in Section 11,
a Participant shall have a vested and nonforfeitable interest in the Excess
Benefit to the same extent and in the same manner as the Participant's benefits
become vested under the Retirement Plan.

     7.   Commencement of Benefits
          ------------------------ 

          The Excess Benefit under this Plan shall commence on the later of: (a)
the date on which the Participant is first eligible to begin receiving a benefit
under the Retirement Plan; or (b) the first day of the month next following the
date of the Participant's Severance from the Company.

     8.   Funding of Benefits
          -------------------

          (a)  The Plan shall be unfunded and each Participant shall have the
status of a general unsecured creditor with respect to the Company's obligation
to make payments under this Plan. All benefits payable under the Plan shall be
paid from the Company's general assets, and nothing contained in the Plan shall
require the Company to set aside or hold in trust any funds for the benefit of a
Participant. Any funds of the Company available to pay benefits under the Plan
shall be subject to the claims of general creditors of the Company and may be
used for any purpose by the Company.

          (b)  Notwithstanding the provisions of subsection (a), the Company
may, at the direction, and in the absolute discretion, of the Board of
Directors, transfer to the trustee of one or more trusts established for the
benefit of one or more Participants assets from which all or a portion of the
benefits provided under the Plan will be satisfied, provided that such assets
held in trust shall at all times be subject to the claims of general unsecured
creditors of the Company, and no Participant shall at any time have a prior
claim to such assets.

    9.    Administration of the Plan
          --------------------------

          The Committee shall administer the Plan.  The Committee shall keep a
written record of its action and proceedings regarding the Plan and all dates,
records and documents relating to its administration of the Plan. The Committee
is authorized to interpret the Plan, to make, amend and rescind such rules as it
deems necessary for the proper administration of the Plan, to make all other
determinations

                                      -3-
<PAGE>
 
necessary or advisable for the administration of the Plan and to correct any
defect or supply any omission or reconcile any inconsistency in the Plan in the
manner and to the extent that the Committee deems desirable to carry the Plan
into effect. The powers and duties of the Committee shall include, without
limitation, the following:

          (a)  Resolving all questions relating to the eligibility of an
Employee to become a Participant;

          (b)  Determining the amount of benefits payable to Participants and
authorizing and directing the Company with respect to the payment of benefits
under the Plan;

          (c)  Construing and interpreting the Plan whenever necessary to carry
out its intention and purpose and making and publishing such rules for the
regulation of the Plan as are not inconsistent with the terms of the Plan; and

          (d)  Compiling and maintaining all records it determines to be
necessary, appropriate or convenient in connection with the administration of
the Plan.

          Any action taken or determination made by the Committee shall, except
as otherwise provided in Section 11 below, be conclusive on all parties.  No
member of the Committees shall vote on any matter relating specifically to such
member.  In the event that a majority of the members of the Committee will be
specifically affected by any action proposed to be taken (as opposed to being
affected in the same manner as each other Participant in the Plan), such action
shall be taken by the Board of Directors.

          Notwithstanding the foregoing, the Committee may delegate to one or
more persons or entities any or all of the responsibilities, duties or powers of
the Committee under this Plan.

     10.  Claims Procedure
          ----------------

          (a)  If a Participant (hereinafter referred to as the "Claimant") does
not receive the timely payment of the benefits which the Claimant believes are
due under the Plan, the Claimant may make a claim for benefits in the manner
hereinafter provided.

               All claims for benefits under the Plan shall be made in writing
and shall be signed by the Claimant. Claims shall be submitted to a
representative designated by the Committee and hereinafter referred to as the
"Claims Coordinator." If the Claimant does not furnish sufficient

                                      -4-
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information with the claim for the Claims Coordinator to determine the validity
of the claim, the Claims Coordinator shall indicate to the Claimant any
additional information which is necessary for the Claims Coordinator to
determine the validity of the claim.

               Each claim hereunder shall be acted on and approved or
disapproved by the Claims Coordinator within 90 days following the receipt by
the Claims Coordinator of the information necessary to process the claim.

               In the event the Claims Coordinator denies a claim for benefits
in whole or in part, the Claims Coordinator shall notify the Claimant in writing
of the denial of the claim and notify the Claimant of his or her right to a
review of the Claims Coordinator's decision by the Committee. Such notice by the
Claims Coordinator shall also set forth, in a manner calculated to be understood
by the Claimant, the specific reason for such denial, the specific provisions of
the Plan on which the denial is based, a description of any additional material
or information necessary to perfect the claim with an explanation of the Plan's
appeals procedure as set forth in this Section.

               If no action is taken by the Claims Coordinator on an Claimant's
claim within 90 days after receipt by the Claims Coordinator, such claim shall
be deemed to be denied for purposes of the following appeals procedure.

          (b)  Any Claimant whose claim for benefits is denied in whole or in
part may appeal for a review of the decision by the Committee. Such appeal must
be made within three months after the Claimant has received actual or
constructive notice of the denial as provided above. An appeal must be submitted
in writing within such period and must:

               (i)    request a review by the Committee of the claim for
benefits under the Plan;

               (ii)   set forth all of the grounds upon which the Claimant's
request for review is based and any facts in support thereof; and

               (iii)  set forth any issues or comments which the Claimant deems
pertinent to the appeal.

               The Committee shall regularly review appeals by Claimants. The
Committee shall act upon each appeal within 60 days after receipt thereof unless
special circumstances require an extension of the time for processing, in which
case a decision shall be rendered by the Committee as soon as

                                      -5-
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possible but not later than 120 days after the appeal is received by the
Committee.

              The Committee shall make a full and fair review of each appeal and
any written materials submitted by the Claimant in connection therewith. The
Committee may require the Claimant to submit such additional facts, documents or
other evidence as the Committee in its discretion deems necessary or advisable
in making its review. The Claimant shall be given the opportunity to review
pertinent documents or materials upon submission of a written request to the
Committee, provided the Committee finds the requested documents or materials are
pertinent to the appeal.

              On the basis of its review, the Committee shall make an
independent determination of the Claimant's eligibility for benefits under the
Plan. The decision of the Committee on any claim for benefits shall be final and
conclusive upon all parties thereto.

              In the event the Committee denies an appeal in whole or in part,
the Committee shall give written notice of the decision to the Claimant, which
notice shall set forth, in a manner calculated to be understood by the Claimant,
the specific reasons for such denial and which shall make specific reference to
the pertinent provisions of the Plan on which the Committee's decision is based.

     11. Miscellaneous
         -------------
 
         (a) Nothing in the Plan shall confer upon a Participant the right to
continue in the employ of the Company or an Affiliated Company or shall limit or
restrict the right of the Company or any Affiliated Company to terminate the
employment of a Participant at any time with or without cause.

         (b) Except as otherwise provided in the Plan, no right or benefit under
the Plan shall be subject to anticipation, alienation, sale, assignment, pledge,
encumbrance or charge, and any attempt to anticipate, alienate, sell, assign,
pledge, encumber or charge such right or benefit shall be void. No such right or
benefit shall in any manner be liable for or subject to the debts, liabilities
or torts of a Participant. In addition, none of the rights of a Participant are
transferable by inter vivos gift or testamentary disposition.

         (c) The Plan may be amended at any time by the Committee provided such
amendment does not have the effect of increasing, directly or indirectly, the
benefit of any Participant. The Plan may also be amended or terminated by the

                                      -6-
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Board of Directors at any time, and any amendment adopted by the Board of
Directors shall supersede any prior or later amendment adopted by the Committee
that is inconsistent With the action of the Board of Directors. No amendment
shall have the effect of decreasing a Participant's accrued benefit.

          (d)  If any benefit payment hereunder becomes payable to a Participant
determined by the Committee to be under any legal incapacity, payments under
this Plan shall be made instead to the guardian or legal representative of such
person and such payment shall constitute a full and complete discharge of all
obligations under this Plan to the Participant.

          (e)  If multiple claims are received by the Committee with respect to
any benefits payable under this Plan, payment by the Committee to such person or
persons as the Committee determines to be entitled to receive such payment shall
constitute a full and complete discharge of all obligations under this Plan with
respect to such payment. Benefit payments under this Plan may be suspended by
the Committee pending resolution of multiple claims to the satisfaction of the
Committee.

          (f)  If any provision in the Plan is held by a court of competent
jurisdiction to be invalid, void or unenforceable, the remaining provisions
shall nevertheless continue in full force and effect without being impaired or
invalidated in any way.

          (g)  The Plan shall be construed and governed in all respects in
accordance with the law of the State of California.

         Executed at Los Angeles, California this 23rd day of November, 1988.



                                            WHITTAKER CORPORATION

                                            By: /s/ ??
                                               ---------------------
                                               Its:       VP
                                                  ----------------- 

                                      -7-
<PAGE>
 
                        CERTIFIED COPY OF RESOLUTIONS 
                         OF THE BOARD OF DIRECTORS OF 
                             WHITTAKER CORPORATION

          WHEREAS the Board of Directors of this corporation (the "Board")
previously adopted the Whittaker Corporation Excess Benefit Plan (the "Plan");
and

          WHEREAS Section 11(c) of the Plan provides that the Board may amend
the Plan at any time, and the Board has determined that it is now necessary and
appropriate to amend the Plan as hereinafter set forth.

          NOW, THEREFORE, BE IT RESOLVED that Section 3 of the Plan is hereby
amended by adding the following new paragraphs at the end thereof:

               "(g) `Day of Service' means, in the case of any Employee, each
     day during any period commencing with the day on which the Employee first
     enters into active service as an Employee on or following his most recent
     date of rehire by the company or any Affiliated Company and ending on the
     date of his next following Severance.  If an Employee's Severance date is
     the date of his retirement, discharge or voluntary termination of
     employment, then Day of Service shall also include each day between such
     Severance date and the date upon which the Employee recommences active
     service as an Employee if the Employee recommences such active service
     prior to:

                    (l)  The first anniversary of such Severance date if such
     Severance date did not occur during an absence from service by the Employee
     for a reason other than retirement, discharge or voluntary termination of
     employment; or

                    (2)  The first anniversary of the date on which the Employee
     was first absent from service for a reason other than retirement, discharge
     or voluntary termination of employment if such Severance date occurred
     during such absence.

                    Credit for Days of Service shall be given with respect to
     periods of military service to such extent and for such purposes as are
     required by applicable federal law. Credit for Days of Service shall be
     given with respect to service performed for an operating unit, division or
     subsidiary of any corporation, trade or business that is acquired by the
     Company or any Affiliated Company commencing on 
<PAGE>
 
     the effective date of such acquisition. Notwithstanding the provisions of
     paragraph (l), the Board of Directors or the committee by resolution may
     provide that, for purposes of determining Vested Service, credit for Days
     of Service also shall be given with respect to service performed for such
     an entity prior to the effective date of the acquisition. Finally, Days of
     Service shall include any period of service that constitutes service with a
     predecessor employer within the meaning of Section 414(a)(1) of the Code.

                    (h)  `Early Retirement Age' means the date on which a
     Participant attains age 55 and completes at least 10 years of Vested
     Service, as determined for purposes of this Plan and the Retirement Plan.

                    (i)  `Normal Retirement Age' means the date on which a
     Participant attains age 65. Notwithstanding the foregoing, effective with
     respect to Participants who are hired after attaining age 60 and after
     December 31, 1988, Normal Retirement Age means the fifth anniversary of the
     date on which such a Participant becomes a Participant in the Plan.

                    (j)  `Severance' means a Participant's termination of
     employment with the Company and all Affiliated Companies for any reason at
     any time.

                    (k)  `Vested Service' means the number of years of an
     Employee's Vested Service determined according to this subsection. An
     Employee shall be deemed to accrue a full year of Vested Service for each
     calendar year during which he completes at least 365 Days of Service as an
     Employee. In addition, an Employee shall be deemed to accrue a fractional
     year of Vested Service in any calendar year in which he completes one or
     more but less than 365 Days of Service as an Employee. Such fractional year
     of Vested Service shall be computed by dividing the number of Days of
     Service completed by the Employee during such calendar year by 365."

     RESOLVED FURTHER that Section 6 of the Plan is hereby amended in its
entirety to read as follows:

     "6.  Reduction of Excess Benefits
          ----------------------------

          Notwithstanding any provision of the Plan to the contrary, the Excess
     Benefit of each Participant who has a Severance prior to the date

                                       2
<PAGE>
 
     on which he attains Normal Retirement Age and is not again an Employee on
     such date shall be proportionately reduced in accordance with the following
     schedule:

     Participant's Years                             Reduction
     of Vested Service                               Percentage
     -------------------                             ----------
     Less than 5                                        100%
     At least 5                                           0%"

     RESOLVED FURTHER that Section 7 of the Plan is hereby amended in its
entirety to read as follows:

     "7.  Commencement of Benefits
          ------------------------

          The Excess Benefit under this Plan shall commence on the first day of
     the month next following the later of: (a) the date on which the
     Participant has a Severance; (b) in the case of a Participant who completes
     at least 10 years of Vested Service prior to his Severance, the date on
     which the Participant attains Early Retirement Age; or (c) in the case of a
     Participant who does not complete at least 10 years of Vested Service prior
     to his Severance, the date on which the Participant attains Normal
     Retirement Age."

     RESOLVED FURTHER that the last two paragraphs of Section 9 of the Plan are
hereby amended to read as follows:

         "Notwithstanding the foregoing, the Committee may delegate to one or
     more persons or entities any or all of the responsibilities, duties or
     powers of the Committee under this Plan.  Any action taken or determination
     made by the Committee or its delegatees shall, except as otherwise provided
     in Section 11, be conclusive as to all parties.  Neither a member of the
     Committee nor a delegatee may vote on, or take any action with respect to,
     any matter relating to such member or delegatee.  If a delegatee cannot
     take any action with respect to a matter, such action shall be taken by the
     Committee.  Similarly, if a majority of the members of the Committee cannot
     take any action with respect to a matter, such action shall be taken by the
     Board of Directors."

     RESOLVED FURTHER that the first sentence of Section 11(b) of the Plan is
hereby amended by deleting the phrase "Except as otherwise provided in the
Plan," from

                                       3
<PAGE>
 
the beginning thereof.

     RESOLVED FURTHER that Section 11(c) of the Plan is hereby amended by adding
the following two sentences at the end thereof:

     "If the Plan is terminated, no additional Excess Benefits shall accrue
     after the termination date. Any Excess Benefits that have already accrued
     as of the termination date shall be distributed at the time and in the
     manner specified in Section 5(b) and Section 7, above."

     RESOLVED FURTHER that Section 11 of the Plan is hereby amended by moving
Section 11(e) to the end of Section 10 and redesignating Sections 11(f) and
11(g) as Sections 11(e) and 11(f), respectively.

                                       4
<PAGE>
 
     "(i) in a single, lump sum payment to be made on the first day of the month
     next following the date of the Participant's death, or"

     RESOLVED FURTHER that Section VII of the Plan is hereby amended by adding
the following new paragraph at the end thereof:


                            * * * * * * * * * * * *

     I, Edward R. Muller, do hereby certify that I am the duly elected and
acting Secretary of Whittaker Corporation; that the foregoing is a full, true
and correct copy of the resolutions adopted at a meeting of the Board of
Directors of Whittaker Corporation held May 18, 1990, at which meeting a quorum
of said Board was at all times present and acting and that said resolutions have
not been modified or rescinded and are in full force and effect as of the date
of this certificate.

     Date: June 12, 1990

                                                  /s/ Edward R. Muller
                                                  --------------------
                                                      Edward R. Muller
                                                          Secretary
                                      11