SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                  Schedule 13G

                    Under the Securities Exchange Act of 1934

                              (Amendment No.: 1 )*

Name of issuer:                             AMR Corp.

Title of Class of Securities:               Common Stock

CUSIP Number:                               001765106

         Check the following [space] if a fee is being paid with this statement:
n/a . (A fee is not  required  only if the  filing  person:  (1) has a  previous
statement on file  reporting  beneficial  ownership of more than five percent of
the class of  securities  described  in Item 1; and (2) has  filed no  amendment
subsequent  thereto  reporting  beneficial  ownership of five percent or less of
such class.) (See rule 13d-7.)

         *The  remainder  of this cover page shall be filled out for a reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

         The information  required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise  subject to the  liabilities of that section of
the Act but shall be subject to all other  provisions of the Act  (however,  see
the Notes).

(Continued on the following page(s))

                                Page 1 of 4 Pages


13G CUSIP No.: 001765106 1. NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Vanguard Primecap Fund 2. CHECK THE APPROPRIATE [LINE] IF A MEMBER OF A GROUP A. B. X 3. SEC USE ONLY 4. CITIZENSHIP OF PLACE OF ORGANIZATION Delaware (For questions 5-8, report the number of shares beneficially owned by each reporting person with:) 5. SOLE VOTING POWER 9,550,000 6. SHARED VOTING POWER -0- 7. SOLE DISPOSITIVE POWER -0- 8. SHARED DISPOSITIVE POWER -0- 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 9,550,000 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES N/A 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 6.45 12. TYPE OF REPORTING PERSON IV Page 2 of 4 Pages

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ---------- SCHEDULE 13G Under the Securities Act of 1934 ---------- Check the following [line] if a fee is being paid with this statement n/a ITEM 1(A) - NAME OF ISSUER: AMR Corp. ITEM 1(B) - ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES: 4333 Amon Carter Blvd., Fort Worth, TX 76155 ITEM 2(A) - NAME OF PERSON FILING: Vanguard Primecap Fund ITEM 2(B) - TITLE OF CLASS OF SECURITIES: Common Stock ITEM 2(E) - CUSIP NUMBER 001765106 ITEM 3 - TYPE OF FILING: This statement is being filed pursuant to Rule 13d-1. The person filing is an investment company registered under Section 8 of the Investment Company Act. ITEM 4 - OWNERSHIP: (a) Amount Beneficially Owned: 9,550,000 (b) Percent of Class: 6.45 Page 3 of 4 Pages

(c) Number of shares as to which such person has: (i) sole power to vote or direct to vote: 9,550,000 (ii) shared power to vote or direct to vote: -0- (iii) sole power to dispose of or to direct the disposition of: -0- (iv) shared power to dispose or to direct the disposition of: -0- ITEM 5 - OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS: Not applicable ITEM 6 - OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON: Not applicable ITEM 7 - IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY: Not applicable ITEM 8 - IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF GROUP: Not applicable ITEM 9 - NOTICE OF DISSOLUTION OF GROUP: Not applicable ITEM 10 - CERTIFICATION: By signing below I certify than, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purpose or effect. SIGNATURE After reasonable 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. DATE 4-10-2000 BY /S/ RAYMOND J. KLAPINSKY Raymond J. Klapinsky Page 4 of 4 Pages