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                                                                     EXHIBIT 4.2


                                                                  CONFORMED COPY

                       AMENDMENT NO. 5 TO CREDIT AGREEMENT


        AMENDMENT dated as of March 24,1999 among LITTON INDUSTRIES, INC. (the
"BORROWER"), the BANKS listed on the signature pages hereof (the "BANKS"),
MORGAN GUARANTY TRUST COMPANY OF NEW YORK, as Agent (the "AGENT") and WELLS
FARGO BANK, N.A., as Co-Agent (the "CO-AGENT").



                                   WITNESSETH:

        WHEREAS, the parties hereto have heretofore entered into an Amended and
Restated Credit Agreement dated as of December 22, 1994 (as heretofore amended,
the "AGREEMENT") and desire to amend the Agreement as set forth herein;

        NOW, THEREFORE, the parties hereto agree as follows:

        SECTION 1. Definitions; References. Unless otherwise specifically
defined herein, each term used herein which is defined in the Agreement shall
have the meaning assigned to such term in the Agreement. Each reference to
"hereof, "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Agreement shall from and after the date hereof refer to the
Agreement as amended hereby,

        SECTION 2. Definitions. Section 1.01 is amended as follows:

        (a) the definition of "Leverage Ratio" is amended to read as follows:

                "LEVERAGE RATIO" means at any date, the ratio of Total Borrowed
                Funds at such date to Consolidated EBITDA for the period of four
                consecutive fiscal quarters most recently ended on or prior to
                such date; provided that if there shall have been an acquisition
                or disposition of operations during such period, Consolidated
                EBITDA shall be calculated on a pro forma basis giving effect
                thereto as if such acquisition or disposition had occurred on
                the first day of such period.


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        (b) the definition of "Minimum Compliance Level" is amended as follows:



                (i) reference to "$669,000,000" is changed to "925,000,000"; and

                (ii) references to "January 31, 1996" are changed to "October
        31, 1998".

        SECTION 3. Subsidiary Debt Limitation. Section 5.08 is amended to read
as follows:

                    SECTION 5.08. Subsidiary Debt Limitation. The aggregate
                outstanding amount of Debt of Subsidiaries (exclusive of (i)
                Debt secured by a Lien permitted by clause (g) of Section
                5.09, (ii) Debt owing to the Borrower or another Subsidiary and
                (iii) up to $85,000,000 of Debt consisting of obligations in
                respect of industrial revenue bonds) will at no time exceed
                $175,000,000.

        SECTION 4. Year 2000 Compliance. The following Section: 4.13 is added to
read as follows:

                    SECTION 4.13. Year 2000 Compliance. The Borrower has (i)
                initiated a review and assessment of all areas within the
                business and operations of the Borrower and each of its
                Subsidiaries (including those areas affected by suppliers and
                vendors) that could be adversely affected by the "Year 2000
                Problem" (that is, the risk that computer applications used by
                it or any of its Subsidiaries (or their respective suppliers and
                vendors) may be unable to recognize and perform properly
                date-sensitive functions involving certain dates prior to and
                any date after December 31, 1999), (ii) developed a plan and
                timetable for addressing the Year 2000 Problem on a timely basis
                and (iii) to date, implemented such plan in accordance with such
                timetable. The Borrower reasonably believes that all computer
                applications that are material to the business or operations of
                the Borrower or any of its Subsidiaries will on a timely basis
                be able to perform properly date-sensitive functions for all
                dates before and from and after January 1, 2000, except to the
                extent that a failure to do so could not reasonably be expected
                to have a material adverse effect on the business, financial
                condition, results of operations or


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                prospects of the Borrower and its Consolidated Subsidiaries,
                considered as a whole.

        SECTION 5. Representations and Warranties. The Borrower hereby
represents and warrants that as of the date hereof and after giving effect
hereto:

        (a) no Default under the Agreement has occurred and is continuing; and

        (b) each representation and warranty of the Borrower set forth in the
Agreement is true and correct as though made on and as of this date.

        SECTION 6. Governing Law. This Amendment shall be governed by and
construed in accordance with the laws of the State of New York.

        SECTION 7. Counterparts; Effectiveness. This Amendment may be signed in
any number of counterparts, each of which shall be an original, with the same
effect as if the signatures thereto and hereto were upon the same instrument.
This Amendment shall become effective as of the date hereof when the Agent shall
have received duly executed counterparts hereof signed by the Borrower and the
Required Banks (or, in the case of any party as to which an executed counterpart
shall not have been received, the Agent shall have received telegraphic, telex
or other written confirmation from such party of execution of a counterpart
hereof by such party).


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        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first above written.

                           LITTON INDUSTRIES, INC.


                           By:   /s/ Timothy G. Paulson
                              -----------------------------------
                              Title: Vice President and Treasurer


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COMMITMENTS
$45,000,000                MORGAN GUARANTY TRUST COMPANY OF NEW YORK, as Bank
                             and Agent


                           By:   /s/ Robert Bottamedi
                              -------------------------------
                              Title: Vice President




$38,000,000                BANK OF AMERICA NT & SA

                           By:   /s/ Brad W. DeSpain
                              -------------------------------
                              Title: Senior Vice President




$38,000,000                THE BANK OF NEW YORK

                           By: /s/ Jonathan Rollins
                              -------------------------------
                              Title:  Vice President




$38,000,000                THE CHASE MANHATTAN BANK


                           By:   /s/ Richard C. Smith
                              -------------------------------
                              Title: Vice President



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$33,000,000                UBS AG, STAMFORD BRANCH

                           By:   /s/ Richard T. Conway
                              -------------------------------
                              Title: Associate Director,
                                     Loan Portfolio Support, US

                           By:   /s/ Denise M. Clerkin
                              -------------------------------
                              Title: Associate Director,
                                     Loan Portfolio Support, US




$33,000,000                WELLS FARGO BANK, N.A., as Bank and
                             Co-Agent

                           By:   /s/ Frieda Youlios
                              -------------------------------
                              Title:   Vice President

                           By:   /s/ Felynn C. Quilo
                              -------------------------------
                              Title: Assistant Vice President



$25,000,000                MELLON BANK, N.A.

                           By:   /s/ Lawrence C. Ivey
                              -------------------------------
                              Title: Vice President




$20,000,000                THE BANK OF NOVA SCOTIA

                           By:   /s/ Maarten Van Otterloo
                              -------------------------------
                              Title: Senior Relationship Manager


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$20,000,000                CANADIAN IMPERIAL BANK OF COMMERCE


                           By:
                              -------------------------------
                              Title:




$20,000,000                CREDIT SUISSE FIRST BOSTON


                           By:   /s/ Thomas G. Muoio
                              -------------------------------
                              Title:   Vice President


                           By:   /s/ Robert N. Finney
                              -------------------------------
                              Title: Managing Director




$20,000,000                DRESDNER BANK AG


                           By:   /s/ Deborah Slusarczyk
                              -------------------------------
                              Title:   Vice President


                           By:   /s/ B. Craig Erickson
                              -------------------------------
                              Title: Vice President



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$20,000,000                THE FIRST NATIONAL BANK OF CHICAGO

                           By:   /s/ Betty Francis-Samilton
                              -------------------------------
                              Title:   Customer Service Officer



$20,000,000                NATIONSBANK, N.A.

                           By /s/ Brad W. DeSpain
                              -------------------------------
                              Title: Senior Vice President



$20,000,000                THE NORTHERN TRUST COMPANY

                           By:   /s/ James F. T. Monhart
                              -------------------------------
                              Title: Senior Vice President




$10,000,000                BANK OF HAWAII

                           By:
                              -------------------------------
                              Title:



Total Commitments
$400,000,000