NWA Northwest Airline

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of report:  April 15, 2008

Date of earliest event reported:  April 14, 2008

NORTHWEST AIRLINES CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code:  (612) 726-2111

Registrant’s Web site address:   www.nwa.com

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

x Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01               Other Events

On April 14, 2008, Delta Air Lines, Inc. (“Delta”) and Northwest Airlines Corporation (the “Company” or “Northwest”) issued a joint press release announcing that they had entered into an Agreement and Plan of Merger, dated as of April 14, 2008 (the “Merger Agreement”), that provides, among other things, for the Company to be merged with a wholly-owned subsidiary of Delta (the “Merger”).  A copy of the joint press release is attached hereto as Exhibit 99.1.  In addition, Delta and the Company provided supplemental information regarding the proposed transaction in connection with presentations to analysts and investors.   A copy of the investor presentation is attached hereto as Exhibit 99.2.

Forward-Looking Statements

This Current Report on Form 8-K (including information included or incorporated by reference herein) includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995.  Words such as “expect,’ “estimate,” “project,” “budget,” “forecast,” “anticipate,” “intend,” “plan,” “may,” “will,” “could,” “should,” “believes,” “predicts,” “potential,” “continue,” and similar expressions are intended to identify such forward-looking statements.  These forward-looking statements include, without limitation, Delta’s and Northwest’s expectations with respect to the synergies, costs and charges, capitalization and anticipated financial impacts of the merger transaction and related transactions; approval of the merger transaction and related transactions by shareholders; the satisfaction of the closing conditions to the merger transaction and related transactions; and the timing of the completion of the merger transaction and related transactions.

These forward-looking statements involve significant risks and uncertainties that could cause the actual results to differ materially from the expected results. Most of these factors are outside our control and difficult to predict.  Factors that may cause such differences include, but are not limited to, the possibility that the expected synergies will not be realized, or will not be realized within the expected time period, due to, among other things, (1) the airline pricing environment; (2) competitive actions taken by other airlines; (3) general economic conditions; (4) changes in jet fuel prices; (5) actions taken or conditions imposed by the United States and foreign governments; (6) the willingness of customers to travel; (7) difficulties in integrating the operations of the two airlines; (8) the impact of labor relations; and (9) fluctuations in foreign currency exchange rates.  Other factors include the possibility that the merger does not close, including due to the failure to receive required stockholder or regulatory approvals, or the failure of other closing conditions.

Delta and Northwest caution that the foregoing list of factors is not exclusive. Additional information concerning these and other risk factors is contained in Delta’s and Northwest’s most recently filed Forms 10-K.  All subsequent written and oral forward-looking statements concerning Delta, Northwest, the merger, the related transactions  or other matters and attributable to Delta or Northwest or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements above. Delta and Northwest do not undertake any obligation to update any forward-looking statement, whether written or oral, relating to the matters discussed in this news release.

Additional Information About the Merger and Where to Find It

In connection with the proposed merger, Delta will file with the Securities and Exchange Commission (“SEC”) a Registration Statement on Form S-4 that will include a joint proxy statement of Delta and Northwest that also constitutes a prospectus of Delta.  Delta and Northwest will mail the joint proxy statement/prospectus to their stockholders.  Delta and Northwest urge investors and security holders to read the joint proxy statement/prospectus regarding the proposed merger when it becomes available because it will contain important information. You may obtain copies of all documents filed with the SEC regarding this transaction, free of charge, at the SEC’s website (www.sec.gov). You may also obtain these documents, free of charge, from Delta’s website (www.delta.com) under the tab “About Delta” and then under the heading “Investor Relations” and then under the item “SEC Filings.” You may also obtain these documents, free of charge, from Northwest’s website (www.nwa.com) under the tab “About Northwest” and then under the heading “Investor Relations” and then under the item “SEC Filings and Section 16 Filings.”

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Delta, Northwest and their respective directors, executive officers and certain other members of management and employees may be soliciting proxies from Delta and Northwest stockholders in favor of the merger. Information regarding the persons who may, under the rules of the SEC, be deemed participants in the solicitation of Delta and Northwest stockholders in connection with the proposed merger will be set forth in the proxy statement/prospectus when it is filed with the SEC. You can find information about Delta’s executive officers and directors in its Annual Reports on Form 10-K (including any amendments thereto), Current Reports on Form 8-K and other documents that have previously been filed with the SEC since April 30, 2007 as well as in its definitive proxy statement to be filed with the SEC related to Delta’s 2008 Annual Meeting of Stockholders. You can find information about Northwest’s executive officers and directors in its Annual Reports on Form 10-K (including any amendments thereto), Current Reports on Form 8-K and other documents that have previously been filed with the SEC since May 31, 2007 as well as in its definitive proxy statement to be filed with the SEC related to Northwest’s 2008 Annual Meeting of Stockholders. You can obtain free copies of these documents from Delta and Northwest using the contact information above.

Item 9.01               Financial Statements and Exhibits

(d)           Exhibits

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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