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                                                                    Exhibit 10.4

                                 FIRST AMENDMENT
                TO THE THIRD AMENDED AND RESTATED LOAN AGREEMENT

This First Amendment to the Third Amended and Restated Loan Agreement is dated
as of March 21, 2003 and is by and among Whitney National Bank ("Lender"), a
national banking association, and Conrad Shipyard, L.L.C. ("Borrower"), a
Louisiana limited liability company, and Orange Shipbuilding Company, Inc.
("Orange"), a Texas corporation, and Conrad Industries, Inc. ("Conrad"), a
Delaware corporation, (with Orange and Conrad collectively referred to as
"Guarantor").

     WHEREAS, the parties hereto entered into a Loan Agreement dated March 19,
1998 as amended by the Third Amended and Restated Loan Agreement dated as of
July 18, 2002 (the "Loan Agreement") which is hereby amended; and

     WHEREAS, the parties hereto desire to amend the Loan Agreement.

     NOW THEREFORE, for good and adequate consideration the receipt of which is
hereby acknowledged, Borrower, Guarantor and Lender do hereby agree as follows:

     1. Borrower and Lender do hereby amend the Loan Agreement as follows:

     a. Page 3, Paragraph titled DEBT SERVICE COVERAGE RATIO, is hereby amended
     to read as follows:

          "Debt Service Coverage Ratio" shall remain the ratio calculated for
     each fiscal year of Borrower, of Cash Flow to Consolidated Funded Debt
     Payments.

     b. Page 19, Section V, AFFIRMATIVE CONVENANTS, Paragraph (b) DEBT SERVICE
     COVERAGE RATIO is hereby amended to read as follows:

         (b) Debt Service Coverage Ratio. Borrower on a consolidated basis with
         Guarantor and each Subsidiary shall maintain during the existence of
         the Loan a Debt Service Coverage Ratio of at least 1.35 to 1.0 as of
         the end of each fiscal year.

     c. Page 19, Section V, AFFIRMATIVE COVENANTS, Paragraph (c) CURRENT RATIO
     is hereby amended to read as follows:

         (c) Current Ratio. Borrower on a consolidated basis with Guarantor and
         each Subsidiary shall maintain at all times during the existence of
         the Loan a ratio of Current Assets (minus any prepaid expenses) to
         Current Liabilities of 1.50 to 1.0 or greater.

     2. In connection with the foregoing and only in connection with the
foregoing, the Loan Agreement is hereby amended, but in all other respects all
of the terms and conditions of the Loan Agreement remain unaffected.

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     3. Borrower and Guarantor acknowledges and agrees that this First Amendment
to the Third Amended and Restated Loan Agreement shall not constitute a waiver
of any default(s) under the Loan Agreement or any documents executed in
connection therewith, all of Bank's rights and remedies of Lender being
preserved and maintained.

     THUS DONE AND PASSED on the date set forth above for the purposes herein
expressed.

WHITNEY NATIONAL BANK                       CONRAD SHIPYARD, L.L.C.

By:  /s/ Edgar W. Santa Cruz, III           By:  /s/ Lewis J. Derbes, Jr.
    ---------------------------------           -------------------------------
      Edgar W. Santa Cruz, III                       Lewis J. Derbes, Jr.
Its:  Vice President                        Its:     Vice President and Chief
                                                     Financial Officer


                                            CONRAD INDUSTRIES, INC.

                                            By:  /s/ Lewis J. Derbes, Jr.
                                                -------------------------------
                                                     Lewis J. Derbes, Jr.
                                            Its:     Vice President and Chief
                                                     Financial Officer

                                            ORANGE SHIPBUILDING COMPANY, INC.

                                            By:  /s/ Lewis J. Derbes, Jr.
                                                -------------------------------
                                                     Lewis J. Derbes, Jr.
                                            Its:     Vice President and Chief
                                                     Financial Officer