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                                                                   EXHIBIT 10.13
                                   GUARANTEE
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                  (Litton of Outstanding NGSC Indenture Debt)

          GUARANTEE dated as of April 3, 2001 (this "Guarantee") made by Litton
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Industries, Inc., a Delaware corporation ("Guarantor") in favor of and for the
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benefit of The Chase Manhattan Bank, as trustee (the "Trustee") for the Holders
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(as such term is defined in the Indenture referred to below) of the 8.625% Notes
due 2004, the 9.735% Debentures due 2024, the 7% Notes due 2006, the 7.75%
Debentures due 2016 and the 7.875% Debentures due 2026 (collectively, the

"Securities") of Northrop Grumman Systems Corporation (formerly Northrop Grumman
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Corporation) (the "Company").
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          WHEREAS, the Company has entered into an Indenture dated as of October
15, 1994 between the Company and the Trustee (as amended, modified and
supplemented from time to time with respect to the Securities, the "Indenture").
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Capitalized terms not otherwise defined herein shall have the meanings set forth
in the Indenture; and

          WHEREAS, Guarantor and the Company are both subsidiaries of Northrop
Grumman Corporation (formerly NNG, Inc.); and

          WHEREAS, in consideration for the guarantee of the Securities by the
Guarantor, the Company has agreed to guarantee certain outstanding indenture
debt of the Guarantor.

          NOW, THEREFORE, in consideration of the foregoing, the Guarantor
hereby agrees as follows:

          SECTION 1.  Guarantee; Limitation of Liability.
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          (a) The Guarantor irrevocably and unconditionally guarantees as a
primary obligor and not merely as a surety, to the Trustee and to each Holder of
a Security authenticated and delivered by the Trustee the due and punctual
payment of the principal of and any premium and interest on such Security
(including, in case of default, interest on overdue principal and interest) and
including any additional interest required to be paid according to the terms of
the Securities or the Indenture, when due, whether at stated maturity, upon
redemption or repayment, upon declaration of acceleration or otherwise according
to the terms of the Securities or the Indenture and the due and punctual
performance of all other obligations of the Company to such Holder or the
Trustee, all in accordance with the terms of the Securities and the Indenture
(such obligations being the "Guaranteed Obligations"), and agrees to pay any and
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all expenses (including reasonable counsel fees and expenses) incurred by such
Holder or the Trustee in enforcing any rights under this Guarantee.  Without

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limiting the generality of the foregoing, the Guarantor's liability shall extend
to all amounts that constitute part of the Guaranteed Obligations and would be
owed by the Company to such Holder or the Trustee under the Securities or the
Indenture but for the fact that they are unenforceable or not allowable due to
the existence of a bankruptcy, reorganization or similar proceeding involving
the Company because it is the intention of the Guarantor, the Trustee and the
Holders that the Guaranteed Obligations should be determined without regard to
any rule of law or order that might relieve the Company of any portion of the
Guaranteed Obligations.

          (b) Notwithstanding anything to the contrary in this Agreement, the
Guarantor hereby, and the Trustee and each Holder by accepting the benefits of
this Guarantee, confirms that it is its intention that the guarantee by the
Guarantor pursuant to this Guarantee together with each other guarantee by such
Guarantor of Participating Indebtedness (as defined below) shall not constitute
a fraudulent transfer or conveyance for purposes of any applicable provisions of
Title 11 of the United States Code, the Uniform Fraudulent Conveyance Act, the
Uniform Fraudulent Transfer Act, or any similar federal or state law.  To
effectuate the foregoing intention, the obligations of the Guarantor under this
Guarantee and each other guarantee of Participating Indebtedness shall be
limited, collectively, to such maximum amount as will, after giving effect to
such maximum amount and all other liabilities of such Guarantor, contingent or
otherwise, that are relevant under such laws, and after giving effect to any
rights to subrogation, reimbursement, indemnification or contribution of such
Guarantor pursuant to applicable law or pursuant to any agreement, result in the
obligations of such Guarantor in respect of such maximum amount not constituting
a fraudulent transfer or conveyance.  The Trustee and each Holder by accepting
the benefits of this Guarantee confirms its intention that, in the event of a
bankruptcy, reorganization or other similar proceeding of the Guarantor in which
concurrent claims are made upon such Guarantor hereunder and under any other
guarantee of Participating Indebtedness, to the extent such claims will not be
fully satisfied, each such claimant with a valid claim against the Guarantor
shall be entitled to a ratable share of all payments by such Guarantor in
respect of such concurrent claims.  For purposes of this Section l(b),
"Participating Indebtedness" means any Indebtedness (as defined below) of the
Company that is guaranteed by such Guarantor pursuant to a guarantee (i) the
incurrence of which is not prohibited by the terms of the Indenture or any
agreement governing any other Participating Indebtedness then outstanding (or,
if so prohibited by the Indenture or any such agreement, is permitted as a
result of a consent or waiver thereunder) and (ii) that contains a limitation of
liability and confirmation of intention regarding ratability of payments on
substantially the terms set forth in this Section l(b).  "Indebtedness" means
any indebtedness, whether or not contingent, in respect of borrowed money or
evidenced by bonds, notes, debentures or similar instruments or letters of
credit and, to the extent not otherwise included, the guarantee by the Company
of any indebtedness of any other Person.

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          (c) Anything contained herein to the contrary notwithstanding, the
liability of the Company in respect of the Securities guaranteed by the
Guarantor hereunder shall not be limited by the terms of Section l(b).

          SECTION 2.  Guarantee Absolute.  The Guarantor guarantees that the
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Guaranteed Obligations will be paid or performed strictly in accordance with the
terms of the Securities and the Indenture, regardless of any law, regulation or
order now or hereafter in effect in any jurisdiction affecting any of such terms
or the rights of any Holder with respect thereto.  The obligations of the
Guarantor under this Guarantee are independent of the Guaranteed Obligations,
and a separate action or actions may be brought and prosecuted against such
Guarantor to enforce this Guarantee, irrespective of whether any action is
brought against the Company or whether the Company is joined in any such action
or actions.  The liability of the Guarantor under this Guarantee shall be
absolute and unconditional irrespective of:

          (a) any lack of validity or enforceability of the Securities or the
     Indenture or any agreement or instrument relating to the Securities or the
     Indenture or any failure to enforce the provisions thereof;

          (b) any renewal, extension or other change in the time, manner or
     place of payment or performance of, or in any other term of, all or any of
     the Guaranteed Obligations, or any other amendment or waiver of or any
     consent to the departure from the Securities or the Indenture;

          (c) any settlement, compromise, release or discharge, or acceptance or
     refusal of any offer of performance with respect to, or any substitution
     for, the Guaranteed Obligations or any agreement related thereto and/or any
     subordination of the payment of the same to the payment of any other
     obligations;

          (d) any taking, exchange, release or non-perfection of any mortgage,
     lien, pledge, charge, security interest or encumbrance of any kind, whether
     or not filed, recorded or otherwise perfected under applicable law (each a
     "Lien"), in any real or personal property to secure payment or performance
      ----
     of any or all of the Guaranteed Obligations (whether now or hereafter
     granted, the "Collateral"), or any taking, release, amendment, waiver of,
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     or consent to the departure from, any other guarantee, for all or any of
     the Guaranteed Obligations;

          (e) any manner of application of Collateral, or proceeds thereof, to
     all or any of the Guaranteed Obligations, or any manner of sale or other
     disposition of any Collateral or any other assets of the Company or any
     Subsidiary;

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          (f) any change, restructuring or termination of the corporate
     structure or existence of the Company or any Subsidiary; or

          (g) any other circumstance (including, without limitation, any statute
     of limitations) that might otherwise constitute a defense available to, or
     a discharge of, the Company or the Guarantor of the Guaranteed Obligations.

          This Guarantee shall continue to be effective or be reinstated, as the
case may be, if at any time any payment of any of the Guaranteed Obligations is
rescinded or must otherwise be returned by any Holder or the Trustee upon the
insolvency, bankruptcy or reorganization of the Company or for any other reason,
all as though such payment had not been made.  The Guarantor further agrees, to
the fullest extent that it may lawfully do so, that, as between such Guarantor
on the one hand, and the Holders and the Trustee, on the other hand, (i) the
maturity of the obligations guaranteed hereby may be accelerated as provided in
Article Five of the Indenture for the purposes of this Guarantee,
notwithstanding any stay, injunction or other prohibition extant under any
applicable bankruptcy law preventing such acceleration in respect of the
obligations guaranteed hereby and (ii) in the event of any declarations of
acceleration of such obligations as provided in Article Five of the Indenture,
such obligations (whether or not due and payable) shall forthwith become due and
payable by the Guarantor for the purpose of this Guarantee.  In addition,
without limiting the foregoing provision, upon effectiveness of an acceleration
under Article Five of the Indenture, the Trustee shall promptly make a demand
for payment on the Securities under this Guarantee provided for hereunder and
not discharged.

          SECTION 3. Waivers.
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          (a) The Guarantor hereby waives:  (i) promptness, diligence,
presentment, notice of acceptance and any other notice with respect to any of
the Guaranteed Obligations and this Guarantee, (ii) any requirement to file any
claims with a court in the event of merger or bankruptcy of the Company or any
guarantor of the Guaranteed Obligations, (iii) any right to require a proceeding
first against the Company or any other guarantor of the Guaranteed Obligations,
(iv) the benefit of discussion or protest or notice with respect to any such
Securities or the Indebtedness evidenced thereby, (v) any requirement that any
Holder or the Trustee protect, secure, perfect or insure any Lien or any
Collateral subject thereto or exhaust any right or take any action against the
Company or any other Person or any Collateral, (vi) any defense arising by
reason of the incapacity, lack of authority or any disability or other defense
of the Company, (vii) any defense based upon any statute or rule of law which
provides that the obligation of a surety must be neither larger in amount nor in
any other respects more burdensome than that of the principal, (viii) any
defense based upon any errors or omissions of the Trustee or the Holders'
administration of the

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Guaranteed Obligations, and (ix) any rights to set-offs, recoupments and
counterclaims.

          (b) The Guarantor hereby irrevocably waives all right to trial by jury
in any action, proceeding or counterclaim (whether based on contract, tort or
otherwise) arising out of or relating to any of the Securities or the Indenture,
the transactions contemplated thereby or the actions of the Trustee in the
negotiation, administration, performance or enforcement thereof.

          SECTION 4.  Financial Condition of the Company.  The Guarantor
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represents and warrants that it is presently informed of the financial condition
of the Company and of all other circumstances which a diligent inquiry would
reveal and which bear upon the risk of nonpayment of the Guaranteed Obligations.
The Guarantor hereby covenants that it will continue to keep itself informed of
the Company's financial condition and of all other circumstances which bear upon
the risk of nonpayment and hereby waives any duty on the part of the Trustee or
any Holder to disclose or discuss with such Guarantor its assessment, or such
Guarantor's assessment, of the financial condition of the Company.

          SECTION 5.  Subrogation.  The Guarantor will not exercise any rights
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that it may acquire by way of subrogation under this Guarantee, by any payment
made hereunder or otherwise, until all the Guaranteed Obligations shall have
been indefeasibly paid in full in cash.  If any amount shall be paid to the
Guarantor on account of any such subrogation rights at any time when all the
Guaranteed Obligations shall not have been paid in full, such amount shall be
held in trust for the benefit of the Holders and the Trustee and shall forthwith
be paid to the Trustee, on behalf of the Holders, to be credited and applied to
the Guaranteed Obligations, whether matured or unmatured.

          SECTION 6.  Amendments, Etc.  No amendment or waiver of any provision
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of this Guarantee and no consent to any departure by the Guarantor therefrom
shall in any event be effective unless the same shall be in writing and signed
by the Trustee, on behalf of the Holders, pursuant to the provisions of Article
Nine of the Indenture, and then such waiver or consent shall be effective only
in the specific instance and for the specific purpose for which given.

          SECTION 7.  Notices, Etc.  All notices and other communications
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provided for hereunder shall be in writing and delivered in person or mailed by
first-class mail, if to the Guarantor, addressed to it at the address of the
Company at 1840 Century Park East, Los Angeles, California 90067, Attention:
Corporate Vice President and Secretary, if to any Holder, addressed to it c/o
the Trustee at 450 West 33rd Street, 15th Floor, New York, New York 10001,
Attention:  Institutional Trust Services, and if to the Trustee, addressed to it
at 450 West 33rd Street, 15th Floor, New York, New York 10001, Attention:
Institutional Trust Services, or as to any

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party at such other address as shall be designated by such party in a written
notice to each other party. All such notices and other communications shall,
when mailed by first class mail, be effective when deposited in the first class
mails.

          SECTION 8.  No Waiver; Remedies.  No failure on the part of any Holder
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or the Trustee to exercise, and no delay in exercising, any right hereunder
shall operate as a waiver thereof; nor shall any single or partial exercise of
any right hereunder preclude any other or further exercise thereof or the
exercise of any other right.  The remedies herein provided are cumulative and
not exclusive of any remedies provided by law.

          SECTION 9.  Continuing Guarantee.  This Guarantee is a continuing
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guarantee and shall (a) remain in full force and effect until the earlier of the
payment in full (including deemed payment pursuant to Section 1302 of the
Indenture) of the Guaranteed Obligations and all other amounts payable under
this Guarantee, and the termination of this Guarantee pursuant to Section 10 of
this Guarantee, (b) subject to the terms hereof, be binding upon the Guarantor,
its respective successors and assigns and (c) inure to the benefit of and be
enforceable by each Holder and the Trustee and their respective successors,
transferees and assigns.

          SECTION 10.  Guarantor May Consolidate, Etc., on Certain Terms. Except
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with the consent of the Holders of Securities as provided in the Indenture, the
Guarantor may not consolidate with or merge into another entity, or convey,
transfer or lease its properties and assets substantially as an entirety to any
Person unless:

          (a) any successor entity is a corporation, partnership or trust
     organized and validly existing under the laws of the United States or any
     state thereof;

          (b) the successor entity assumes the Guarantor's obligations under
     this Guarantee;

          (c) after giving effect to the transaction, no Event of Default, and
     no event which, after notice or lapse of time or both, would become an
     Event of Default, has occurred and is continuing; and

          (d) the Guarantor delivers to the Trustee certificates and opinions to
     the effect that the transaction complies with the Indenture.

          Upon any such consolidation or merger or conveyance, transfer or lease
of the properties and assets of the Guarantor as an entirety to any Person, the
successor Person will succeed to, and be substituted for, such Guarantor under
the Indenture and this Guarantee, and the Guarantor, except in the case of a
lease, will be relieved of all obligations and covenants under the Indenture and
this Guarantee.

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          SECTION 13. Governing Law.  This Guarantee shall be governed by, and
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construed in accordance with, the law of the State of New York.

          SECTION 14.  Counterparts.  This Guarantee may be executed in one or
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more counterparts, each of which shall be deemed an original but all of which
together will constitute one and the same instrument.

                            [SIGNATURE PAGE FOLLOWS]

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          IN WITNESS WHEREOF, the Guarantor has caused this Guarantee to be duly
executed and delivered by its officer thereunto duly authorized as of the date
first above written.

                                  LITTON INDUSTRIES, INC.

                                  By /s/Albert F. Myers
                                     ------------------------------------
                                     Name: Albert F. Myers
                                     Title:  Corporate Vice President and
                                     Treasurer

                                  Attest:

                                  By /s/John H. Mullan
                                     ------------------------------------
                                     Name: John H. Mullan
                                     Title:  Corporate Vice President and
                                     Secretary

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