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Item 2.02 Results of Operations and Financial Condition.

On January 31, 2008, Allis-Chalmers Energy Inc., a Delaware corporation (the “Company”) announced its earnings expectations for the fourth quarter and year ended December 31, 2007. A copy of the Company’s press release announcing the expectations is attached as Exhibit 99.2 to this Current Report on Form 8-K.

In accordance with General Instruction B.2 of Form 8-K, the information set forth in this Item 2.02 and in the exhibit referenced in this Item 2.02 shall be deemed to be “furnished” and not be deemed “filed” for purposes of the Securities Exchange Act of 1934, as amended.

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On January 29, 2008, Burt A. Adams resigned as President and Chief Operating Officer of the Company, effective February 28, 2008. Mr. Adams will continue under the terms of his current employment agreement until the effective date of his resignation. Mr. Adams will remain as a member of the Company’s board of directors.

The Company will be making presentations beginning January 31, 2008 to certain investors. The presentation materials are attached hereto as Exhibit 99.1 to this report.

The information provided in Item 2.02 above is incorporated by reference in this Item 7.01.

In accordance with General Instruction B.2 of Form 8-K, the information set forth in this Item 7.01 and in the exhibits referenced in this Item 7.01 shall be deemed to be “furnished” and not be deemed “filed” for purposes of the Securities Exchange Act of 1934, as amended.

Important Additional Information

In connection with the proposed merger transaction between Allis-Chalmers and Bronco Drilling Company, Inc., Allis-Chalmers and Bronco Drilling will file a joint proxy statement/prospectus and both companies will file other relevant documents concerning the proposed merger transaction with the SEC. INVESTORS ARE URGED TO READ THE JOINT PROXY STATEMENT/PROSPECTUS WHEN IT BECOMES AVAILABLE, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION REGARDING THE MERGER. Investors and security holders may obtain a free copy of the joint proxy statement/prospectus (when available) and the other documents free of charge at the website maintained by the SEC at www.sec.gov.

The documents filed with the SEC by Allis-Chalmers may be obtained free of charge from Allis-Chalmers’ website at www.alchenergy.com or by calling Allis-Chalmers’ Investor Relations department at (713) 369-0550. The documents filed with the SEC by Bronco Drilling may be obtained free of charge from Bronco Drilling’s website at www.broncodrill.com or by calling Bronco Drilling’s Investor Relations department at (405) 242-4444. Investors and security holders are urged to read the joint proxy statement/prospectus and the other relevant materials when they become available before making any voting or investment decision with respect to the proposed merger transaction. Allis-Chalmers and Bronco Drilling and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the respective stockholders of each company in connection with the merger transaction. Information about the directors and executive officers of Allis-Chalmers and their ownership of Allis-Chalmers common stock is set forth in its proxy statement filed with the SEC on April 30, 2007. Information about the directors and executive officers of Bronco Drilling and their ownership of Bronco Drilling common stock is set forth in its proxy statement filed with the SEC on April 30, 2007. Investors may obtain additional information regarding the interests of such participants by reading the joint proxy statement/prospectus for the Merger when it becomes available.

(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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