<PAGE>
                                                                    EXHIBIT 10.1

                                                                  EXECUTION COPY


               FIRST AMENDMENT dated as of November 26, 2002 (this
          "Amendment"), to the Five-Year Revolving Credit Agreement dated as of
          March 30, 2001 (the "Credit Agreement"), among NORTHROP GRUMMAN
          CORPORATION, a Delaware corporation formerly known as NNG, Inc. (the
          "Company"); NORTHROP GRUMMAN SYSTEMS CORPORATION, a Delaware
          corporation formerly known as Northrop Grumman Corporation ("Northrop
          Operating"); LITTON INDUSTRIES, INC., a Delaware corporation ("Litton
          Operating" and, together with the Company and Northrop Operating, the
          "Borrowers"); the LENDERS (as defined in Article 1 of the Credit
          Agreement), JPMORGAN CHASE BANK and CREDIT SUISSE FIRST BOSTON, as
          Co-Administrative Agents, JPMORGAN CHASE BANK, as Payment Agent,
          SALOMON SMITH BARNEY INC., as Syndication Agent, and THE BANK OF NOVA
          SCOTIA and DEUTSCHE BANC SECURITIES INC. (formerly known as Deutsche
          Banc Alex. Brown Inc.), as Co-Documentation Agents.

     A. Pursuant to the Credit Agreement, the Lenders have extended, and have
agreed to extend, credit to the Borrowers.

     B. The Borrowers have informed the Lenders that the Company intends to
acquire all of the outstanding equity interest of TRW Inc., an Ohio corporation
("TRW"), pursuant to the Agreement and Plan of Merger (the "TRW Merger
Agreement") dated as of June 30, 2002, by and among TRW, the Company and
Richmond Acquisition Corp., a newly formed Ohio corporation and wholly owned
subsidiary of the Company ("Richmond Acquisition"). Pursuant to the TRW Merger
Agreement, Richmond Acquisition shall be merged with and into TRW and TRW will
become a wholly owned subsidiary of the Company (the "TRW Acquisition").

     C. The Borrowers have further informed the Lenders that, following the TRW
Acquisition, the Company intends to cause TRW to sell, spin off to the
shareholders of the Company or otherwise transfer or dispose of all or a portion
of TRW automotive business (any such transfer or disposition being called the
"TRW Automotive Business Disposition").

     D. In connection with the foregoing, the Borrowers have requested that the
Lenders agree to amend certain provisions of the Credit Agreement as provided
herein. The Lenders whose signatures appear below, constituting the Required
Lenders, are willing, on the terms and subject to the conditions set forth
herein, so to amend the Credit Agreement.

     E. Capitalized terms used but not defined herein shall have the meanings
assigned to them in the Credit Agreement as amended hereby.

     Accordingly, in consideration of the mutual agreements herein contained and
other good and valuable consideration, the sufficiency and receipt of which are
hereby acknowledged, the parties hereto agree as follows:

     SECTION 1. Amendments. (a) Section 1.01 of the Credit Agreement is hereby
amended by:

     (i) inserting in the appropriate alphabetical order the following new
definitions:

          "Amendment  No. 1" means Amendment No. 1 and Agreement dated as of
     November 26, 2002, to this Agreement.


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                                                                               2

          "JPMorgan" means JPMorgan Chase Bank and its successors.

          "Subsidiary Guarantee Agreement" means a Subsidiary Guarantee
     Agreement substantially in the form of Exhibit A to Amendment No. 1,
     between a Subsidiary and the Co-Administrative Agents, acting on behalf of
     the Lenders.

          "TRW" means TRW Inc., an Ohio corporation.

          "TRW Automotive Business Disposition" shall mean any sale, spin-off to
     the shareholders of the Company or other transfer or disposition of all or
     a portion of TRW's automotive business in which the consideration received
     by the Company and its Subsidiaries (other than Subsidiaries that are part
     of TRW's automotive business) is not less than $2,000,000,000. For purposes
     of the foregoing, (a) consideration received by the Company and its
     Subsidiaries will be deemed to include, without duplication, the amount of
     any cash consideration received, the fair market value at the closing of
     such disposition of any non-cash consideration received and the principal
     amount of any Indebtedness of the Company or TRW that is (i) assumed by one
     or more of the entities disposed of, (ii) assumed by the purchaser of all
     or a portion of TRW's automotive business or (iii) refinanced with the
     proceeds of Indebtedness issued by one or more of the entities disposed of;
     provided, in the case of Indebtedness referred to in the foregoing clauses
     (i) and (ii), that, after giving effect to such disposition, neither the
     Company nor any of its Subsidiaries shall remain directly or contingently
     liable for, and none of the respective assets of such persons will be
     subject to any Lien securing, the payment of such Indebtedness, and (b)
     consideration received by the Company and its Subsidiaries will not be
     deemed to include any interest in TRW's automotive business that is
     retained by the Company or any of its Subsidiaries in connection with the
     TRW Automotive Business Disposition.

     (ii) deleting the definition of "Chase".

     (b) The definition of the term "Loan Documents" set forth in Section 1.01
of the Credit Agreement is hereby amended and restated in its entirety to read
as follows:

          "Loan Documents" shall mean this Agreement, each promissory note, if
     any, delivered pursuant to this Agreement, and each Subsidiary Guarantee
     Agreement, as such documents may be amended, modified, supplemented or
     restated from time to time.

     (c) Section 1.05 of the Credit Agreement is hereby amended and restated in
its entirety to read as follows:

          SECTION 1.05. Certain Financial Covenant Calculations. (a) For
     purposes of determining the Funded Debt to Consolidated EBITDA Ratio and
     the Consolidated Fixed Charge Coverage Ratio for the four-quarter periods
     ending at the first three fiscal quarter ends of the Company following the
     closing of the TRW Acquisition (each such four-quarter period being called
     a "Designated Period"):

               (i) Consolidated EBITDA and Capital Expenditures shall be
          determined on a pro forma basis combining (A) the results of the
          Company and its consolidated subsidiaries (other than TRW and its
          subsidiaries) for such Designated Period and (B) the segment results
          reported by TRW (or, following the TRW Acquisition, the Company) for
          TRW's automotive business, space and electronics business and systems
          business, including any such business that is accounted for as a
          discontinued operation (but only, in the case of each such business of

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                                                                               3

          TRW, to the extent that such business continues to be wholly owned by
          TRW at the end of such Designated Period); and

               (ii) Interest Expense shall be determined on a pro forma basis
          combining (A) the results of the Company and its consolidated
          subsidiaries (including the results of TRW and its subsidiaries for
          fiscal quarters ending after the closing of the TRW Acquisition, but
          not for fiscal quarters ended prior to such closing) and (B) for each
          fiscal quarter ended prior to the closing of the TRW Acquisition, an
          amount equal to (1) 7% of the Funded Debt of TRW and its subsidiaries
          at the end of such fiscal quarter multiplied by (2) a fraction of
          which the numerator is the number of days in such fiscal quarter and
          the denominator is 365.

     The Company agrees that the financial statements delivered by it pursuant
     to Section 5.01 for each of the first three fiscal quarters ending after
     the closing of the TRW Acquisition will include or be accompanied by
     consolidating and segment information sufficient to permit the computations
     required by the foregoing paragraphs (i) and (ii).

          (b) Without limiting the foregoing (but subject to the final
     parenthetical in paragraph (a)(i) above), for purposes of all financial
     computations under Sections 6.08, 6.09 and 6.10 of this Agreement following
     the closing of the TRW Acquisition, balance sheet and income statement
     items that would otherwise be excluded from the Company's consolidated
     balances and results because they relate to discontinued operations of TRW
     and its subsidiaries will be included in such balances and results as if
     they related to continuing operations of TRW and such subsidiaries.

          (d) Section 6.02 of the Credit Agreement is hereby amended by:

          (i) replacing the proviso in paragraph (d) thereof with the following:

          "provided that the aggregate fair market value of all assets sold,
          transferred or otherwise disposed of in reliance upon this clause (d)
          after March 30, 2001, shall not exceed an amount equal to 15% of the
          consolidated assets of the Company as of September 30, 2002;"

          (ii) deleting the word "and" at the end of paragraph (c) thereof,
     inserting the word "and" at the end of paragraph (d) thereof and inserting
     the following new paragraph (e):

               "(e) the TRW Automotive Business Disposition;".

          (e) The first paragraph of Section 6.04(d) of the Credit Agreement is
     hereby amended to read as follows:

               "(d) the Company or any of the Subsidiaries may (i) acquire the
          business of, or all or any significant part of the Property of, or all
          or any significant part of the capital stock of, or be a party to any
          acquisition of, any Person engaged in the same line of business as the
          Company and its Subsidiaries, taken as a whole, or a related line of
          business (whether directly or through the merger of a Wholly-Owned
          Subsidiary with that Person) and (ii) complete the TRW Acquisition,
          subject, in each case, to the following:"

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                                                                               4

     (e) Section 6.05 of the Credit Agreement is hereby amended by deleting the
word "and" at the end of paragraph (f), by relettering paragraph (g) as
paragraph (h) and by inserting after paragraph (f) the following new paragraph
(g):

          "(g) Liens on assets of TRW and its subsidiaries existing at the time
     of the TRW Acquisition and not created in contemplation of such
     Acquisition, as set forth on the attached Schedule 6.05(g); and"

     (f) Section 6.06(g) of the Credit Agreement is hereby amended by changing
the percentages "5%" and "2%" to "7%' and "3%", respectively.

     (g) Section 6.07(a)(xiii) of the Credit Agreement is hereby amended and
restated in its entirety to read as follows:

          "(xiii) additional Indebtedness of the Company and the Subsidiaries
     (including Capital Lease Obligations and other Indebtedness secured by
     Liens permitted under clauses (e) and (f) of Section 6.05 hereof) in an
     aggregate amount at any one time outstanding not exceeding $750,000,000."

     (h) Section 6.07(b) of the Credit Agreement is hereby amended and restated
in its entirety to read as follows:

          "(b) The Borrowers will not permit the Indebtedness of all of the
     Subsidiaries that are not Borrowers (other than Indebtedness (a) owing to
     the Company or another Subsidiary and (b) of any Subsidiary that shall have
     executed and delivered to the Payment Agent a Subsidiary Guarantee
     Agreement together with evidence satisfactory to the Payment Agent of the
     power and authority of such Subsidiary to enter into such Agreement) to
     exceed $425,000,000 in the aggregate at any one time outstanding."

     (i) Section 6.10 of the Credit Agreement is hereby amended and restated in
its entirety to read as follows:

          SECTION 6.10. Fixed Charge Coverage Ratio. The Company will not permit
     the Fixed Charge Coverage Ratio as of any Fiscal Date to be less than 1.25x
     until the earlier of (x) the completion of the TRW Automotive Business
     Disposition and (y) December 30, 2003. At any time thereafter, or in the
     event that the TRW Acquisition shall not have been consummated, the Company
     will not permit the Fixed Charge Coverage Ratio as of any Fiscal Date in
     any period set forth below to be less than the ratio set forth below
     opposite such period:
<TABLE>
<CAPTION>

                  Fiscal Date                          Ratio
                  -----------                          -----
     <S>                                               <C>
     December 31, 2002 - September 30, 2003            1.75x
     December 31, 2003 - September 30, 2004            2.00x
     December 31, 2004 and each Fiscal Date            2.25x
</TABLE>

     (j) The following new Section 5.08 is inserted at the end of Article V of
the Credit Agreement:

          SECTION 5.08. Completion of TRW Automotive Business Disposition. In
     the event the TRW Acquisition shall be completed, the Company will cause
     the TRW Automotive Business Disposition to be completed not later than
     December 31, 2003.

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                                                                               5

     (k) Clause (d) of Article VII of the Credit Agreement is amended by
inserting "5.08," immediately prior to "Section 10.14" therein.

     (l) References to "Chase" in the Credit Agreement shall be deleted and
"JPMorgan" substituted therefor.

     (m) Schedule 6.05(g) hereto is substituted for the existing Schedule
6.05(g) to the Credit Agreement.

     (n) The Lenders agree, notwithstanding any provision to the contrary in the
Credit Agreement, that Litton Operating may be merged with and into Northrop
Operating in a transaction in which no Person other than the Company receives
any consideration, and that, from and after the effectiveness of such merger,
all references in the Credit Agreement to Litton Operating shall be deemed to be
references to Northrop Operating.

     SECTION 2. Representations and Warranties. To induce the Lenders to enter
into this Amendment, the Borrowers represent and warrant to such parties that
(a) the representations and warranties set forth in Article III of the Credit
Agreement are true and correct in all material respects on and as of the date
hereof (and will be true and correct after giving effect to the TRW
Acquisition), except to the extent such representations and warranties expressly
relate to an earlier date; and (b) no Default or Event of Default has occurred
and is continuing (or will have occurred and be continuing after giving effect
to the TRW Acquisition).

     SECTION 3. Amendment Fee. The Company agrees to pay in immediately
available funds to each Lender that executes and delivers to the Payment Agent
(or its counsel) a copy of this Amendment at or prior to 5:00 p.m., New York
City time, on November 26, 2002, an amendment fee (the "Amendment Fee") in an
amount equal to 0.10% of the amount of such Lender's Revolving Commitment
(whether used or unused) as of the date hereof; such Amendment Fee will be
payable on November 27, 2002. Notwithstanding the foregoing, the Amendment Fee
shall not be payable unless this Amendment shall have been executed and
delivered by the Required Lenders. Once paid, the Amendment Fee shall not be
refundable.

     SECTION 4. Conditions to Effectiveness. The amendments provided for in
Section 1 shall become effective on the date (the "Amendment Effective Date") on
which the following conditions are satisfied; provided that the effectiveness of
the amendments set forth in paragraphs (a) (other than the provisions of
paragraph (a)(i) adding definitions of TRW and TRW Automotive Business
Disposition), (b), (d)(i), (h), (l) and (n) of Section 1 will be subject only to
the satisfaction of the condition set forth in paragraph (a) below:

     (a) the Payment Agent shall have received counterparts of this Amendment
that, when taken together, bear the signatures of the Borrowers and the Required
Lenders;

     (b) the TRW Acquisition shall have been or shall on the Amendment Effective
Date be consummated on substantially the terms set forth in the TRW Merger
Agreement as in effect on the date hereof;

     (c) the existing Indebtedness and all credit and similar agreements of TRW
(other than the Indebtedness and agreements listed on Schedule 1) shall have
been or shall on the Amendment Effective Date be repaid and terminated, and all
Liens securing such Indebtedness (other than the Liens listed on Schedule
6.05(g) hereto) shall have been or shall on the Amendment Effective Date be
released, and the Payment Agent shall have received such evidence as it shall
have reasonably requested as to the satisfaction of such condition;

     (d) the Company shall have delivered to the Payment Agent with respect to
the TRW Acquisition a certificate of a senior accounting or financial officer
satisfying the requirements of Section 6.04(d) of the Credit Agreement and
confirming the accuracy as of the Amendment Effective Date of the
representations set forth in Section 2; and

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                                                                               6

     (e) TRW shall have executed and delivered to the Payment Agent a Subsidiary
Guarantee Agreement together with evidence satisfactory to the Payment Agent of
the power and authority of TRW to enter into such Agreement.

     Notwithstanding the foregoing, if the Amendment Effective Date shall not
have occurred by January 31, 2003, then the amendments provided for in Section 1
shall terminate and be of no further force or effect.

     SECTION 5. Effect of Amendment. Except as expressly set forth herein, this
Amendment shall not by implication or otherwise limit, impair, constitute a
waiver of, or otherwise affect the rights and remedies of the Lenders, the
Co-Administrative Agents, the Syndication Agent or the Co-Documentation Agents
under the Credit Agreement or any other Loan Document, and shall not alter,
modify, amend or in any way affect any of the terms, conditions, obligations,
covenants or agreements contained in the Credit Agreement or any other Loan
Document, all of which are ratified and affirmed in all respects and shall
continue in full force and effect. Nothing herein shall be deemed to entitle any
Loan Party to a consent to, or a waiver, amendment, modification or other change
of, any of the terms, conditions, obligations, covenants or agreements contained
in the Credit Agreement or any other Loan Document in similar or different
circumstances. This Amendment shall apply and be effective only with respect to
the provisions of the Credit Agreement specifically referred to herein. After
the date hereof, any reference to the Credit Agreement shall mean the Credit
Agreement, as modified hereby. This Amendment shall constitute a "Loan Document"
for all purposes of the Credit Agreement and the other Loan Documents.

     SECTION 6. Counterparts. This Amendment may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which when so executed and delivered shall be deemed an original, but all such
counterparts together shall constitute but one and the same contract. Delivery
of an executed counterpart of a signature page of this Amendment by facsimile
transmission shall be as effective as delivery of a manually executed
counterpart hereof.

     SECTION 7. Applicable Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

     SECTION 8. Headings. The headings of this Amendment are for purposes of
reference only and shall not limit or otherwise affect the meaning hereof.

     SECTION 9. Expenses. The Borrower agrees to reimburse the Payment Agent for
all out-of-pocket expenses in connection with this Amendment, including the
reasonable fees, charges and disbursements of Cravath, Swaine & Moore, counsel
for the Co-Administrative Agents.

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                                                                               7

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by their duly authorized officers, all as of the date and year
first above written.

                                    NORTHROP GRUMMAN CORPORATION,


                                    by:
                                       -----------------------------------------
                                       Name:
                                       Title:


                                    NORTHROP GRUMMAN SYSTEMS
                                    CORPORATION,


                                    by:
                                       -----------------------------------------
                                       Name:
                                       Title:

                                    LITTON INDUSTRIES, INC.,


                                    by:
                                       -----------------------------------------
                                       Name:
                                       Title:


                                    JPMORGAN CHASE BANK,
                                    individually and as Co-Administrative Agent
                                    and Payment Agent,



                                    by:
                                       -----------------------------------------
                                       Name:
                                       Title:


                                    CREDIT SUISSE FIRST BOSTON,
                                    individually and as Co-Administrative Agent,


                                    by:
                                       -----------------------------------------
                                       Name:
                                       Title:


                                    by:
                                       -----------------------------------------
                                       Name:
                                       Title: