SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                _______________

                                  SCHEDULE TO

           Tender Offer Statement under Section 14(d)(1) or 13(e)(1)
                     of the Securities Exchange Act of 1934

                               (Amendment No. 7)

                            LITTON INDUSTRIES, INC.

                       (Name of Subject Company (issuer))

                          NORTHROP GRUMMAN CORPORATION
                             (formerly NNG, Inc.)
                             LII ACQUISITION CORP.
                     Northrop Grumman Systems Corporation
                    (formerly Northrop Grumman Corporation)

                       (Name of Filing Persons (offeror))

                    Common Stock, Par Value $1.00 Per Share
                         (including associated rights)
                         (Title of Class of Securities)

                                 538021 10 6
                     (CUSIP Number of Class of Securities)

       Series B $2 Cumulative Preferred Stock, Par Value $5.00 Per Share

                         (Title of Class of Securities)

                                  538021 40 3

                     (CUSIP Number of Class of Securities)

                                 W. Burks Terry
                  Corporate Vice President and General Counsel
                          Northrop Grumman Corporation
                             1840 Century Park East
                         Los Angeles, California  90067
                                 (310) 553-6262

  (Name, Address and Telephone Number of Person Authorized to Receive Notices
        and Communications on Behalf of the Person(s) Filing Statement)

                                    Copy to:

                                Andrew E. Bogen
                         Gibson, Dunn & Crutcher LLP
                            333 South Grand Avenue
                      Los Angeles, California  90071-3197
                                (213) 229-7159

[ ] Check the box if the filing relates solely to preliminary communications
    made before the commencement of a tender offer.

[ ] Check the appropriate boxes to designate any transactions to which this
    statement relates:

      [X] third party tender offer           [ ] going-private transaction
              subject to Rule 14d-1                    subject to Rule 13e-3

      [ ] issuer tender offer                [ ] amendment to Schedule 13D
              subject to Rule 13e-4                    under Rule 13d-2


     Check the following box if the filing is a final amendment reporting the
     results of the tender offer.   [X]



        Northrop Grumman Systems Corporation (formerly Northrop Grumman
Corporation), a Delaware corporation ("Parent" or "Systems"), LII Acquisition
Corp., and Northrop Grumman Corporation (formerly NNG, Inc.) ("Northrop"),
hereby amend and supplement their Tender Offer Statement on Schedule TO
originally filed on January 5, 2001 (the "Schedule TO"), as subsequently amended
from time to time, with respect to the Offer to Purchase or Exchange (the
"Offer") (a) all of the issued and outstanding shares of common stock, par value
$1.00 per share (the "Common Stock") of Litton Industries, Inc., a Delaware
corporation (the "Company"), together with any associated rights to purchase
preferred stock of the Company (together with the Common Stock, the "Common
Shares") and (b) all of the outstanding shares of Series B $2 Cumulative
Preferred Stock, par value $5.00 per share (the "Preferred Shares"), of the
Company.


                                       2


Items 1 through 11

   As permitted by General Instruction F to Schedule TO, the information set
forth in Amendment No. 2 to the Registration Statement on Form S-4 (Commission
file No. 333-54800) filed with the SEC by Northrop Grumman Corporation (formerly
NNG, Inc.) on March 27, 2001 is incorporated by reference into this Tender
Offer Statement on Schedule TO.

Item 8.   Interest in Securities of the Subject Company

     Item 8 of the Schedule TO is hereby amended and supplemented to include the
following information:

Expiration of the Offer and Results

     The Offer expired at Midnight, New York City time, on Monday, April 2,
2001. EquiServe Trust Company N.A., the Depositary for the Offer, has informed
Northrop that at that time, 44,660,440 Common Shares and 240,632 Preferred
Shares had been validly tendered and not properly withdrawn by the Company's
stockholders. At approximately 12:30 a.m., New York City Time, on Tuesday, April
3, 2001, Northrop accepted for purchase or exchange all of the Common Shares and
Preferred Shares validly tendered and not properly withdrawn prior to the
expiration of the Offer. Based on information provided to Northrop by the
Company and Bank of New York, the Company's transfer agent, there were
45,900,722 Common Shares and 410,643 Preferred Shares outstanding as of March
28, 2001. Therefore, the number of Common Shares and Preferred Shares accepted
for purchase or exchange by Northrop represent approximately 97.3% and 58.6% of
the Common Shares and Preferred Shares outstanding as of March 28, 2001,
respectively.

     Based on these numbers, Northrop will issue the full allotment of
13,000,000 shares of Northrop common stock and 3,500,000 shares of Northrop
preferred stock available for issuance pursuant to the Offer.  In addition, the
number of shares of Northrop common stock and Northrop preferred stock issuable
to the Company's stockholders requesting such securities will be subject to
proration, because the number of such securities requested by tendering holders
of Common Shares exceeds the respective amounts of such securities available for
issuance pursuant to the Offer.

Proration Factors

     Based on the tender numbers reported by the Depositary, the total number of
Common Shares tendered for Northrop preferred stock was approximately
24,962,376, which substantially exceeds the maximum preferred stock
consideration available in the Offer.  As a result, all tenders of Common Shares
for Northrop preferred stock are subject to a proration factor of 0.175269414.
Based on the tender numbers reported by the Depositary, the total number of
Common Shares tendered for Northrop common stock, together with the total number
of Common Shares tendered for Northrop common stock that could not be satisfied
due to pro ration, was approximately 16,352,503. Of such number, 11,237,071
shares were subject to Alternative A elections and 5,115,432 shares were subject
to Alternative B elections. As a result of these amounts, the Common Shares
tendered for Northrop common stock with an Alternative A election are subject to
a proration factor of 0.790733996. There will be no proration of (a) Common
Shares tendered (or deemed tendered as a result of proration) for Northrop
common stock with an Alternative B election, (b) Common Shares tendered for cash
or (c) Preferred Shares tendered for cash.

Average Closing Prices of Northrop Grumman Corporation Common Stock

     The average of the closing prices for Northrop Grumman Corporation common
stock on the NYSE for the five consecutive trading days ending on the second
full trading day before the expiration of the Offer was $86.42.  As described in
the Offer to Purchase or Exchange filed as a part of Northrop's Registration
Statement on Form S-4 dated February 1, 2001 and subsequently amended (the
"Prospectus"), this number is used in determining both the amounts payable to
tendering holders of Common Shares in lieu of fractional shares of Northrop
common stock, and to determine the common stock exchange ratio for the Offer.
Accordingly, all references in the Prospectus to the average of the closing
prices for Northrop Grumman Corporation common stock on the NYSE for the five
consecutive trading days ending on the second full trading day before the
expiration of the Offer should be read to refer to $86.42.

     As described in the section of the Prospectus entitled "The Offer - Cash
Instead of Fractional Shares of NNG Stock," each tendering holder of Common
Shares that would otherwise receive a fractional share of Northrop common stock
will instead be paid cash in an amount equal to the fraction of the share of
Northrop common stock (expressed as a decimal and rounded to the nearest 0.01 of
a share) multiplied by $86.42.

     As described throughout the Prospectus, the number of shares of Northrop
common stock issuable in exchange for Common Shares is determined by dividing
$80.25 by the average of the closing prices for Northrop Grumman Corporation
common stock on the New York Stock Exchange for the five consecutive trading
days ending on the second full trading day before the expiration of the Offer
(i.e. $86.42). Therefore, each Common Share exchanged for Northrop common stock
pursuant to the Offer will be exchanged for 0.9286 shares of Northrop common
stock.

Item 12. Exhibits

     Item 12 of the Schedule TO is hereby amended and supplemented to include
the following exhibits:

     (a)(5)(xv)   Press release issued by Systems on March 23, 2001.

     (a)(5)(xvi)  Press release issued by Systems on March 23, 2001.

     (a)(5)(xvii) Press release issued by Systems on March 30, 2001.

     (a)(5)(xviii)Press release issued by Northrop on April 3, 2001.

     (a)(5)(xix)  Press release issued by Northrop on April 3, 2001.

     (a)(5)(xx)   Press release issued by Northrop on April 4, 2001.

     (a)(5)(xxi)  Press release issued by Northrop on April 9, 2001.

     (a)(5)(xxii) Press release issued by Northrop on April 18, 2001.

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                                   SIGNATURE

     After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.


                              LII ACQUISITION CORP.


                              By:  /s/ John H. Mullan
                                 -------------------------------------------
                              Name: John H. Mullan
                                   -----------------------------------------
                              Title: Secretary
                                    ----------------------------------------


                              NORTHROP GRUMMAN SYSTEMS CORPORATION
                              (formerly Northrop Grumman Corporation)

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


                              NORTHROP GRUMMAN CORPORATION
                              (formerly NNG, Inc.)

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


Dated: April 18, 2001

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                                 EXHIBIT INDEX



(a)(1)(i)*    Offer to Purchase, dated January 5, 2001.

(a)(1)(ii)*   Letter of Transmittal, Common Stock and Preferred Stock, each
              dated January 5, 2001.

(a)(1)(iii)*  Notice of Guaranteed Delivery, Common Stock and Preferred Stock,
              each dated January 5, 2001.

(a)(1)(iv)*   Notice to Participants in the Litton Industries Employees Stock
              Purchase Plan prior to December 1, 1993, dated January 5, 2001.

(a)(1)(v)*    Notice to Participants in the Litton Industries Employees Stock
              Purchase Plan after November 1, 1994, dated January 5, 2001.

(a)(1)(vi)*   Letter of Transmittal, Common Stock and Preferred Stock, each
              dated February 1, 2001.

(a)(1)(vii)*  Notice of Guaranteed Delivery, Common Stock and Preferred Stock,
              each dated February 1, 2001.

(a)(1)(viii)* Notice to Participants in the Litton Industries Employees Stock
              Purchase Plan prior to December 1, 1993, dated February 1, 2001.

(a)(1)(ix)*   Notice to Participants in the Litton Industries Employees Stock
              Purchase Plan after November 1, 1994, dated February 1, 2001.

(a)(1)(x)*    Letter to Brokers, Dealers, Commercial Banks, Trust Companies and
              other Nominees, Common Stock and Preferred Stock, dated February
              1, 2001.

(a)(1)(xi)*   Letter to Clients, Common Stock and Preferred Stock, each dated
              February 1, 2001.

(a)(1)(xii)*  Guidelines for Certification of Taxpayer Identification
              Number on Substitute Form W-9.

(a)(2)        None.

(a)(3)        Not applicable.

(a)(4)*       Registration Statement on Form S-4 filed with the SEC by NNG, Inc.
              on February 1, 2001 and incorporated by this reference.

(a)(5)(i)*    Letter to Brokers, Dealers, Commercial Banks, Trust Companies and
              other Nominees, Common Stock and Preferred Stock, dated January 5,
              2001.

(a)(5)(ii)*   Letter to Clients, Common Stock and Preferred Stock, each dated
              January 5, 2001.

(a)(5)(iii)*  Guidelines for Certification of Taxpayer Identification Number on
              Substitute Form W-9.

(a)(5)(iv)*   Press release issued by Parent on December 21, 2000 (incorporated
              by reference to Schedule TO-C filed with the Securities and
              Exchange Commission on December 20, 2000).

(a)(5)(v)*    Summary Advertisement as published in the Wall Street Journal on
              January 5, 2001.

(a)(5)(vi)*   Press release issued by Parent on January 8, 2001.

(a)(5)(vii)*  Press release issued by Parent on January 16, 2001.

(a)(5)(viii)* Joint Press release issued by Parent and the Company on
              January 24, 2001.

(a)(5)(ix)*   Summary Advertisement as published in the Wall Street Journal
              on February 1, 2001.

(a)(5)(x)*    Press release issued by Parent on February 22, 2001.

(a)(5)(xi)*   Press release issued by Parent on February 27, 2001.

(a)(5)(xii)*  Press release issued by Parent on March 1, 2001.

(a)(5)(xii)*  Press release issued by Parent on March 9, 2001.

(a)(5)(xiv)*  Press release issued by Parent on March 16, 2001.

(a)(5)(xv)    Press release issued by Systems on March 23, 2001.

(a)(5)(xvi)   Press release issued by Systems on March 23, 2001.

(a)(5)(xvii)  Press release issued by Systems on March 30, 2001

(a)(5)(xviii) Press release issued by Northrop on April 3, 2001.

(a)(5)(xix)   Press release issued by Northrop on April 3, 2001.

(a)(5)(xx)    Press release issued by Northrop on April 4, 2001.

(a)(5)(xxi)   Press release issued by Northrop on April 9, 2001.

(a)(5)(xxii)  Press release issued by Northrop on April 18, 2001.

(b)(i)*       Financing Commitment Letter dated December 20, 2000 from Credit
              Suisse First Boston and The Chase Manhattan Bank relating to
              $6,000,000,000 aggregate principal amount of senior credit
              facilities.

(b)(ii)*      $6,000,000,000 Senior Credit Facilities Commitment Letter dated
              January 30, 2001 from Credit Suisse First Boston, The Chase
              Manhattan Bank and JP Morgan.

(b)(iii)      Form of $2,500,000,000 364-day Revolving Credit Facility among
              NNG, Inc., Parent, Litton Industries, Inc., the Lenders party
              thereto, The Chase Manhattan Bank and Credit Suisse First Boston,
              as Co-Administrative Agents, Salomon Smith Barney, Inc., as
              Syndication Agent, and the Bank of Nova Scotia and Deutsche Banc
              Alex.Brown Inc. as Co-Documentation Agents (incorporated by
              reference to Exhibit 10.6 to Amendment No. 2 to Registration
              Statement on Form S-4 (Commission File No. 333-54800) filed by
              NNG, Inc. on March 27, 2001).

(b)(iv)       Form of $2,500,000 Five Year Credit Agreement among NNG, Inc.,
              Parent, Litton Industries, Inc., the Lenders party thereto, The
              Chase Manhattan Bank and Credit Suisse First Boston, as Co-
              Administrative Agents, Salomon Smith Barney, Inc., as Syndication
              Agent, and The Bank of Nova Scotia and Deutsche Banc Alex.Brown
              Inc. as Co-Documentation Agents (incorporated by reference to
              Exhibit 10.7 to Amendment No. 2 to Registration Statement on Form
              S-4 (Commission File No. 333-54800) filed by NNG, Inc. on March
              27, 2001).

(c)           Not applicable.

(d)(1)*       Merger Agreement, dated as of December 21, 2000, by and among
              Parent, Purchaser and the Company.

(d)(2)*       Confidentiality Agreement dated June 23, 2000, between Parent and
              the Company.

(d)(3)*       Letter Agreement dated December 21, 2000, between Ronald D. Sugar
              and Parent.

(d)(4)*       Amended and Restated Agreement and Plan of Merger dated as of
              January 23, 2001 among Northrop Grumman Corporation, Litton
              Industries, Inc., NNG, Inc. and LII Acquisition Corp.

(d)(5)*       Stockholder's Agreement dated as of January 23, 2001 among
              Northrop Grumman Corporation, NNG, Inc. and Unitrin, Inc.

(d)(6)*       Registration Rights Agreement dated as of January 23, 2001 by and
              among Northrop Grumman Corporation, NNG, Inc. and Unitrin, Inc.

(e)           Not applicable.

(f)*          Section 262 of the Delaware General Corporation Law (included as
              Schedule II to the Offer to Purchase).

(g)           None.

(h)           None.

*  Previously filed.

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