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            This Amendment No. 5 (this “Amendment”) amends the Schedule 13D filed July 21, 2004 which amended and restated, in its entirety, the Schedule 13D dated July 7, 1977 (as later amended by amendments dated August 31, 1977, September 23, 1977 and March 13, 1980). Other than as set forth herein, there has been no material change in the information set forth in the Schedule 13D filed on July 21, 2004. Capitalized terms not defined in this Amendment No. 5 shall have the respective meanings ascribed thereto in the Schedule 13D filed on July 21, 2004.

              No change.

              No change.

              After giving effect to the transactions contemplated by the Underwriting Agreement (defined below), H&P Drilling’s current ownership of Shares is as set forth in rows 7-11 and 13 of the cover page hereto.

              On October 13, 2004, Helmerich & Payne International Drilling Co. (“H&P Drilling”), a wholly owned subsidiary of Helmerich & Payne, Inc. (“H&P”), entered into an underwriting agreement (“Underwriting Agreement”) with Atwood Oceanics, Inc. (the “Company”), and Goldman, Sachs & Co., Credit Suisse First Boston LLC, Jefferies & Company, Inc., Raymond James & Associates, Inc., Stifel, Nicolaus & Company, Incorporated, Howard Weil Incorporated, Petrie Parkman & Co., Inc. and Sanders, Morris Harris, Inc. (collectively, the “Underwriters”) related to the offering (the “Public Offering”) of 2,175,000 shares of the Company’s common stock, par value $1.00 per share (the “Common Stock”) pursuant to effective shelf registration statements on Form S-3 (File Nos. 333-92388 and 333-117534) previously filed with the Securities and Exchange Commission. Two of H&P’s executive officers, Hans Helmerich and George S. Dotson, are directors of the Company. The offering includes 1,175,000 shares of Common Stock to be sold by the Company and 1,000,000 shares of Common Stock to be sold by H&P Drilling. The Underwriters have the option to purchase up to 325,000 additional shares of Common Stock from the Company to cover over-allotments, if any. A copy of the Underwriting Agreement is filed as Exhibit 1.1 to the Form 8-K filed by Helmerich & Payne, Inc. with the Securities and Exchange Commission on October 14, 2004, and is incorporated herein by reference.

              (a) and (b). No change except as follows: The Reporting Persons currently have beneficial ownership of 2,000,000 Shares. This amount constitutes

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approximately 13.3% of the outstanding Shares, based upon a total of 15,039,201 Shares currently outstanding. The number of Shares outstanding is based on the number of Shares outstanding as of June 30, 2004, as disclosed in the Company’s registration statement on Form S-3 filed on July 21, 2004, plus 1,175,000 shares of Common Stock sold by the Company to the Underwriters. Each of the Reporting Persons has the sole power to vote or direct the vote and the sole power to dispose or direct the disposition of the Shares beneficially owned by the Reporting Persons.

              (c)   Pursuant to the Underwriting Agreement, and under the registration statements noted in Item 4 above, H&P Drilling sold an aggregate of 1,000,000 shares of Common Stock to the Underwriters on October 19, 2004 at a price per share of $45.8325 that resulted in total proceeds to H&P Drilling of $45,832,500.

              (d)   No change.

              (e)   No change.

              In connection with the Public Offering, Hans Helmerich and George Dotson, each an executive officer of H&P and a director of the Company, executed a lock-up agreement (“Lock-up Agreement”) in favor of the Underwriters. Messrs. Helmerich and Dotson each generally agreed under the Lock-up Agreement that, during a period of 180 days after the date of the final prospectus covering the Public Offering, such person would not offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of any shares of Common Stock of the Company, or any options or warrants to purchase any shares of Common Stock of the Company, or any securities convertible into, exchangeable for or that represent the right to receive shares of Common Stock of the Company. Attached hereto and incorporated herein by reference is Exhibit 2, the form of Lock-up Agreement signed by Messrs. Helmerich and Dotson. Except as described above and in the responses to Items 4 and 5 above, which responses are hereby incorporated by reference, to the best knowledge of the Reporting Persons there are no contracts, agreements, arrangements, understandings or relationships (legal or otherwise) between the persons enumerated in Item 2 and any other person with respect to the securities of the Company other than as disclosed in the information set forth in the Schedule 13D filed on July 21, 2004.

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SIGNATURES

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

Dated: October 19, 2004

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EXHIBIT INDEX

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