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                 UNITED STATE SECURITIES AND EXCHANGE COMMISSION
                             Washington, D. C. 20549
                                   FORM 10-Q/A
                                 AMENDMENT NO. 1

                                   (Mark One)

     [X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDED JUNE 30, 2005 OR

     [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM _______________ TO

                          COMMISSION FILE NUMBER 1-2199

                           ALLIS-CHALMERS ENERGY INC.

             (Exact name of registrant as specified in its charter)



           DELAWARE                                               39-0126090
-------------------------------                              -------------------
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization)                              Identification No.)


                5075 WESTHEIMER, SUITE 890, HOUSTON, TEXAS 77056
                ------------------------------------------------
               (Address of principal executive offices) (Zip code)

                                 (713) 369-0550
                                 --------------
               Registrant's telephone number, including area code

           SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:

          Title of Security:                                Name of Exchange:
Common Stock, par value $0.01 per share                  American Stock Exchange

        SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT: NONE


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes [X] No [ ]

Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Act). Yes [ ] No [X]

At August 3, 2005 there were 14,022,800 shares of common stock outstanding.

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                           ALLIS-CHALMERS ENERGY INC.

                                    FORM 10-Q

                  FOR THE QUARTERLY PERIOD ENDED JUNE 30, 2005

                                INTRODUCTORY NOTE
                                -----------------

We are filing this Amendment No. 1 to our Quarterly report on Form 10-Q for the
quarter ended June 30, 2005 to properly disclose Item 4 as a result of our
restatements related to Earnings Per Share and Joint Venture Accounting. The
restatements are discussed in more detail in Note 6 to the consolidated
financial statements that were originally filed for the quarter ended June 30,
2005.


                               TABLE OF CONTENTS
                               -----------------

                                     PART I


ITEM                                                                      PAGE
----                                                                      ----

4.       Controls and Procedures..........................................  3


                                     PART II


2.       Exhibits and Reports on Form 8-K.................................  4

Signatures and Certifications.............................................  5


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ITEM 4. CONTROLS AND PROCEDURES.


DISCLOSURE CONTROLS AND PROCEDURES. We maintain disclosure controls and
procedures that are designed to ensure that information required to be disclosed
in our reports under the Securities Exchange Act of 1934, as amended, are
recorded, processed, summarized and reported within the time periods specified
in the SEC's rules and forms, and that such information is accumulated and
communicated to management, including our chief executive officer and chief
financial officer, as appropriate, to allow timely decisions regarding required
disclosures. Our internal control system is designed to provide reasonable
assurance regarding the preparation and fair presentation of published financial
statements. All internal control systems are designed based in part upon certain
assumptions about the likelihood of future events, and, no matter how well
designed, have inherent limitations. Therefore, even those systems determined to
be effective can provide only reasonable assurance with respect to financial
statement preparation and presentation and may not prevent or detect all
misstatements.

Management, including our chief executive officer and our chief financial
officer, has evaluated the effectiveness of our "disclosure controls and
procedures" (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) as of the
end of the period covered by this Report (the "Evaluation Date"). Management has
concluded that, as of the Evaluation Date, due to the deficiencies described
below, our controls and procedures over financial reporting were not effective
to enable us to record, process, summarize, and report information required to
be included in our SEC filings within the required time period, and to ensure
that such information is accumulated and communicated to our management,
including our chief executive officer and chief financial accounting officer, to
allow timely decisions regarding required disclosure. As described below, we are
taking steps to remediate the deficiencies in our control over the financial
reporting process.

On August 4, 2005, our Board of Directors, upon the recommendation of the Audit
Committee of our Board of Directors, concluded that our previously issued
financial statements for the periods from July 1, 2003 through March 31, 2005,
were required to be restated to correct the understatement of net income per
share which resulted from a miscalculation of the number of basic and diluted
shares outstanding on a weighted average basis in accordance with SFAS No. 128,
EARNINGS PER SHARE. The deficiency resulted from errors discovered by our
independent accountants on August 1, 2005, while reviewing our financial
statements for the quarter ended June 30, 2005. The major components of the
errors were as follows:

     o    For all periods involved we had not applied the treasury stock method
          of accounting for options and warrants as prescribed in SFAS No. 128.
          Specifically, we overstated diluted shares outstanding because we
          failed to reduce diluted shares outstanding by the number of shares
          that could be purchased with the proceeds to us from the exercise of
          dilutive warrants and options.
     o    In 2003 and 2004, we overstated diluted shares by not correctly
          calculating the number of common shares into which our preferred stock
          was convertible; by not applying the "if converted" method of
          calculating diluted net earnings which requires that dividends
          actually paid on preferred stock be added to net income attributed to
          common shares in calculating diluted earnings per common share; and by
          continuing to report the preferred shares as dilutive after the
          preferred shares were converted to common stock on April 2, 2004.
     o    During the third quarter of 2004, we misstated the number of common
          shares outstanding on a weighted average basis due to a mathematical
          error in calculating the number of days certain shares issued during
          the quarter were outstanding.

In addition, in March 2005, we restated our financial statements for the year
ended December 31, 2003 and for the three quarters ended September 30, 2004,
relating to our acquisition of a 55% interest in our AirComp, LLC subsidiary in
2003. We originally accounted for the formation of AirComp as a joint venture,
but in February 2005, determined that the transaction should have been accounted
for using purchase accounting pursuant to SFAS No. 141, BUSINESS COMBINATIONS
and accounting for the sale of an interest in a subsidiary in accordance with
SAB No. 51.

We have restated our financial statements as set forth in Note 6 to the
Consolidated Financial Statements contained in Part I, Item 1.

Public Company Accounting Oversight Board ("PCAOB") Auditing Standard No. 2
identifies a number of circumstances that, because of their likely significant
negative effect on internal control over financial reporting, are to be regarded
as at least significant deficiencies as well as strong indicators that a
material weakness exists, including the restatement of previously-issued
financial statements to reflect the correction of a misstatement. Management
evaluated the impact of the restatement of our previously-issued financial
statements on our assessment of our system of internal control and has concluded
that the restatements resulted from the lack of sufficient experienced
accounting personnel resulting in a lack of effective control over the financial
reporting process.

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We have implemented a number of actions that we believe address the deficiencies
in our financial reporting process, including the following:

     o    The addition of experienced accounting personnel with appropriate
          experience and qualifications to perform quality review procedures and
          to satisfy our financial reporting obligation. During August 2004, we
          hired a new chief financial officer and in October of 2004 we hired a
          full-time general counsel. In March 2005, we hired a certified public
          accountant as our financial reporting manager and in July 2005 we
          hired as chief accounting officer a certified public accountant who
          has significant prior experience as a chief accounting officer of a
          publicly traded company.
     o    In the fourth quarter of 2004, we engaged an independent internal
          controls consulting firm which is in the process of documenting,
          analyzing, identifying and correcting weaknesses and testing our
          internal controls and procedures, including our controls over internal
          financial reporting.
     o    Our audit committee dismissed our prior independent auditors in
          October 2004 and engaged new independent auditors who we believe have
          greater experience with publicly traded companies.
     o    We are in the process of implementing new accounting software to
          facilitate timely and accurate reporting.


CHANGE IN INTERNAL CONTROL OVER FINANCIAL REPORTING.

There were no changes in our internal control over financial reporting (as such
term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that
occurred during the period covered by this report that have materially affected,
or are reasonably likely to materially affect, our internal control over
financial reporting, except as follows:

     o    In August 2004, we hired a new chief financial officer.

     o    In October 2004, we hired full-time general counsel

     o    In October 2004, we dismissed out prior independent auditors and
          engaged new independent auditors who we believe have greater
          experience serving publicly traded companies.

     o    In the fourth quarter of 2004, we engaged an independent internal
          controls consulting firm which is in the process of documenting,
          analyzing, identifying and testing internal control. In addition, we
          are improving our financial accounting systems by implementing a more
          integrated accounting software solution.

     o    In March 2005, we hired a certified public accountant to be our
          financial reporting manager.

     o    In July 2005, we reassigned our chief accounting officer to oversee
          our corporate systems and hired a certified public accountant who has
          prior experience as a chief accounting officer of a publicly traded
          company to be our chief accounting officer.


                           PART II. OTHER INFORMATION


ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K

(a) The exhibits listed on the Exhibit Index located at Page 6 of this Quarterly
Report are filed as part of this Form 10-Q/A.


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                                   SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange
Act of 1934, as amended, the registrant has duly caused this report to be signed
on its behalf by the undersigned, thereunto duly authorized on August 16, 2005.


                                              ALLIS-CHALMERS ENERGY INC.
                                              --------------------------
                                                    (REGISTRANT)

                                              /S/ MUNAWAR H. HIDAYATALLAH
                                              ----------------------------------
                                              MUNAWAR H. HIDAYATALLAH
                                              CHIEF EXECUTIVE OFFICER AND
                                              CHAIRMAN

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                                  EXHIBIT INDEX

31.1     Certification of Chief Executive Officer pursuant to Section 302 of the
         Sarbanes-Oxley Act of 2002.

31.2     Certification of Chief Financial Officer pursuant to Section 302 of the
         Sarbanes-Oxley Act of 2002.

32.1     Certification of the Chief Executive Officer and Chief Financial
         Officer pursuant to 18 U.S.C. 1350, as adopted pursuant to Section 906
         of the Sarbanes-Oxley Act of 2002.



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