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                                                                   Exhibit 10.47

                        FIRST AMENDMENT TO LOAN AGREEMENT

     This FIRST AMENDMENT TO LOAN AGREEMENT (the "First Amendment"), dated as of
the 10th day of March, 2004, is made by and between HORIZON VESSELS
INTERNATIONAL, LTD., ("Borrower"), and BOEING CAPITAL CORPORATION ("Lender").

                                   WITNESSETH:

     WHEREAS, Borrower and Lender entered into that certain Loan Agreement dated
as of June 30, 2003 (as the same has been or may hereafter be amended,
supplemented or otherwise modified, the "Loan Agreement"), pursuant to which
Borrower agreed to borrow, and the Lender agreed to lend, upon and subject to
the terms thereof, up to the aggregate principal amount of $35,000,000 (the
"Loan");

     WHEREAS, the Loan was guaranteed by Horizon Offshore, Inc. (the parent
company of Borrower) (the "Parent") and Horizon Vessels, Inc.;

     WHEREAS, the Parent is entering into a certain Purchase Agreement with
Elliott Associates, L.P., as agent, pursuant to which the Parent will issue
senior notes in an aggregate principal amount of not less than $60,000,000 (the
"Note Issuance"), the terms of which Note Issuance have been provided to Lender;
and

     WHEREAS, the parties now desire to modify certain of the terms and
conditions contained in the Loan Agreement.

     NOW, THEREFORE, in consideration of the foregoing recitals and the mutual
covenants and premises contained herein, together with other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto have agreed and do hereby agree as follows:

     1. Capitalized terms used in this First Amendment (including the recitals
hereof) shall have the meanings assigned to them in the Loan Agreement, as
amended by this First Amendment.

     2. Lender hereby consents to the Note Issuance subject to the terms of this
First Amendment. Further, notwithstanding Section 3.2(m) of the Loan Agreement,
Lender hereby consents to the payoff, in total, of the existing $15,000,000 loan
to Horizon Vessels, Inc. by Elliott Associates, L.P. with the proceeds of the
Note Issuance.

     3. The Loan Agreement is hereby amended by adding the following definitions
to the Definitions section thereof in the correct alphabetical order; provided
that to the extent any of the following terms are already defined in the Loan
Agreement, then the following definitions amend and restate such terms in their
entirety:

     "Cash Interest" means the cash portion of Interest Expense.


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     "Current Assets" means all amounts which, in conformity with GAAP, would be
included as current assets on a consolidated balance sheet of the Parent and its
subsidiaries.

     "Current Liabilities" means all amounts which, in conformity with GAAP,
would be included as current liabilities on a consolidated balance sheet of the
Parent and its subsidiaries, excluding revolving loan facilities and any balloon
payment due in the next twelve (12) months.

     "Current Maturities of Long Term Debt" means for the Parent and its
subsidiaries, on a consolidated basis, the principal amount due and payable
during the next succeeding twelve month period on Total Funded Debt of the
Parent and its subsidiaries which has a final maturity more than twelve months
from the date of calculation, excluding all revolving loan facilities and any
balloon payment due in the next twelve (12) months.

     "Current Ratio" means, at any particular date, (a) Current Assets as of
such date divided by (b) Current Liabilities as of such date.

     "EBITDA" means for the Parent and its subsidiaries, on a consolidated
basis, for any period, the sum of (a) Net Income before gains and losses on
sales of assets (to the extent such gains and losses are included in earnings,
plus (b) Tax Expense, plus (c) depreciation and amortization, plus (d) Interest
Expense.

     "EBITDAR" means for the Parent and its subsidiaries, on a consolidated
basis, for any period, the sum of (a) Net Income before gains and losses on
sales of assets (to the extent such gains and losses are included in earnings,
plus (b) Tax Expense, plus (c) depreciation and amortization, plus (d) Interest
Expense, plus (e) restructuring charges, including costs of professional
advisors to the Parent and its subsidiaries (including costs of professional
advisors to the Parent's lenders and other creditors which are required to be
paid by the Parent or its subsidiaries) not to exceed $1,600,000 for the fiscal
year ended December 31, 2004.

     "Fixed Charge Coverage Ratio" means for the Parent and its subsidiaries, on
a consolidated basis, (a) as of September 30, 2004, (i) EBITDA for the quarter
ended as of September 30, 2004, divided by (ii) the sum of (A) Current
Maturities of Long Term Debt as of September 30, 2004 divided by four, plus (B)
Interest Expense for the quarter ended September 30, 2004, plus (C) Tax Expense
for the quarter ended as of September 30, 2004, (b) as of December 31, 2004, (i)
EBITDA for the quarters ended as of September 30, 2004 and December 31, 2004,
divided by (ii) the sum of (A) Current Maturities of Long Term Debt as of
December 31, 2004 divided by two, plus (B) Interest Expense for the quarters
ended as of September 30, 2004 and December 31, 2004, plus (C) Tax Expense for
the quarters ended as of September 30, 2004 and December 31, 2004, (c) as of
March 31, 2005, (i) EBITDA for the quarters ended September 30, 2004, December
31, 2004, and March 31, 2005 divided by (ii) the sum of (A) Current Maturities
of Long Term Debt as of March 31, 2005 times .75 (seventy-five percent), plus
(B) Cash Interest for the quarters ended September 30, 2004, December 31, 2004,
and March 31, 2005, plus (C) Tax Expense for the quarters ended September 30,
2004 , December 31, 2004, and March 31, 2005, and (d) for all quarters ending
thereafter, (i) EBITDA for the four (4) quarters then ended divided by (ii) the
sum of (A) Current Maturities of Long Term Debt as of the quarter then ended,
plus (B) Cash Interest for the four (4) quarters then ended, plus (C) Tax
Expense for the four (4) quarters then ended.


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     "Interest Expense" means, for any period, the consolidated interest expense
of the Parent and its subsidiaries for such period, determined in accordance
with GAAP applied consistently.

     "Net Income" means, for any period, with respect to the Parent and its
subsidiaries, the consolidated net income (or loss) of the Parent and its
subsidiaries for such period, determined in accordance with GAAP applied
consistently (excluding any extraordinary items during such period).

     "Tangible Net Worth" means, at any particular date, all amounts which, in
conformity with GAAP, would be included as stockholder's equity on a
consolidated balance sheet of the Parent and its subsidiaries; provided,
however, there shall be excluded therefrom (a) any amount at which shares of
capital stock of the Parent or any subsidiary appear as an asset on the Parent's
or such subsidiary's balance sheet, (b) goodwill, including any amount, however
designated, that represent the excess of purchase price paid for assets or stock
over the value assigned thereto, (c) patents, trademarks, trade names, and
copyrights, (d) deferred expenses, (e) loans and advances to any stockholder,
director, officer, or employee of the Parent or any subsidiary or any affiliate,
(f) all other assets which are properly classified as intangible assets, and (g)
paid-in-kind interest on the Note Issuance.

     "Tax Expense" means, for any period, on a consolidated basis, the sum of
all tax expense of the Parent and its subsidiaries for such period determined in
accordance with GAAP applied consistently.

     "Total Funded Debt" means, for the Parent and its subsidiaries, on a
consolidated basis, the sum of (a) all indebtedness for borrowed money, whether
or not evidenced by notes, bonds, debentures, notes or similar instruments, (b)
all capital lease obligations, (c) all obligations to pay the deferred purchase
price of property or services (but excluding trade accounts payable or trade
notes in the ordinary course of business that are not past due by more than 90
days), (d) all indebtedness secured by a Lien on the property of the Parent or
any of its subsidiaries, and (f) all letter of credit liabilities.

     4. As a condition precedent to the effectiveness of this First Amendment,
Borrower will provide to Lender a report, in form satisfactory to Lender, on the
current utilization and backlog of work for the Vessel.

     5. The Parent agrees that prior to the third anniversary of the Note
Issuance, all interest and principal payments on the notes issued pursuant
thereto shall be made solely with funds received by the Parent or its
subsidiaries from (a) the certain Offshore Construction Contract dated as of
October 1, 2002, by and between Williams Oil Gathering, L.L.C. ("Williams") and
Horizon Offshore Contractors, Inc., (b) Williams as a result of the lawsuit
entitled Horizon Offshore Contractors, Inc. v. Williams Oil Gathering, L.L.C. et
al., bearing case number 2003-51819 on the docket of the 295th Judicial
District, Harris County, Texas, (c) that certain contract No. PEP-o-AD-317/00
(also known as EPC-64) between Pemex-Exporacion y Produccion (a subsidiary of
Petroleos Mexicanos) and ECH Offshore, S. de. R.L. de C.V., (d) any equity
offering of the Parent or any of its subsidiaries, (e) the sale, transfer,
disposition or use of the U.S. flag vessel PECOS HORIZON, official No. 528068
owned by Horizon Vessels, Inc., and (f) the sale, transfer, disposition or use
of that certain real and personal property owned


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by Horizon Vessels, Inc. located in Port Arthur, Jefferson County, Texas. Any
payments made by the Parent with respect to the Note Issuance in compliance with
the foregoing shall not be subject to any penalty under the Loan Agreement, as
amended hereby.

     6. By the first business day of each year during the term of the Loan
Agreement, Borrower shall, at its cost and expense, provide Lender with (a)
report, in form satisfactory to Lender, on the current utilization and backlog
of work for the Vessel and (b) an appraisal of the Vessel by an appraiser and in
form satisfactory to Lender. Such appraisal shall contain the then current
Orderly Liquidation Value and Fair Market Value of the Vessel, and in the event
the Orderly Liquidation Value of the Vessel as determined by such appraisal is
less than the outstanding principal amount of the Loan, Borrower shall be
required to prepay the Loan in accordance with the prepayment method contained
in Section 1.5(a)(iii) of the Loan Agreement.

     7. The Parent will not permit its Current Ratio as of the last day of any
fiscal quarter to be less than: (a) .90 to 1.00 for the fiscal quarters ending
March 31, 2004 and June 30, 2004; (b) 1.05 to 1.00 for the fiscal quarter ending
September 30, 2004; (c) 1.10 to 1.00 for the fiscal quarter ending December 31,
2004; and (d) 1.10 to 1 for the period ending March 31, 2005 and each period
thereafter.

     8. The Parent and its subsidiaries will at all times maintain Tangible Net
Worth in an amount not less than the sum of (a) $110,000,000, plus (b)
seventy-five percent (75%) of Net Income for each fiscal quarter of the Parent
and its subsidiaries which has been completed as of the date of calculation,
commencing with the fiscal quarter ending March 31, 2004, provided, however,
that in the event that Net Income of the Parent and its subsidiaries is not
greater than zero for any fiscal quarter, an amount equal to zero shall be added
to the calculation of Tangible Net Worth for such fiscal quarter, plus (c)
ninety percent (90%) of the net proceeds of any common stock or other equity
issued by the Parent or any of its subsidiaries after December 31, 2003. The
calculation will exclude the cumulative impact of the paid in kind interest
related to the Note Issuance from both the covenant hurdle and the Company's
calculated Tangible Net Worth. Tangible Net Worth shall be calculated and tested
quarterly as of the last day of each fiscal quarter of the Parent commencing
with the fiscal quarter ending March 31, 2004. Any audit adjustment for the
fiscal year ended December 31, 2003 that results in an adjustment to the equity
accounts in an amount in excess of $53,416,000.00 will adjust the minimum
Tangible Net Worth requirement on a dollar for dollar basis.

     9. The Parent will not permit its Fixed Charge Coverage Ratio as of the
last day of any fiscal quarter to be less than: (a) not applicable for the
fiscal quarters ending March 31, 2004 and June 30, 2004; (b) 1.50 to 1.00 for
the fiscal quarter ending September 30, 2004; (c) 1.40 to 1.00 for the fiscal
quarter ending December 31, 2004; (d) 1.33 to 1 for the nine-month period ending
March 31, 2005; and (e) 1.33 to 1 for each period thereafter on a rolling four
quarter basis.

     10. The Parent will maintain EBITDAR of not less than: (a) negative
$2,500,000 for the three months ending March 31, 2004; (b) negative $4,500,000
for six months ending June 30, 2004; (c) positive $8,000,000 for the nine months
ending September 30, 2004; and (d) positive $20,000,000 for the twelve months
ending December 31, 2004. For the three-month period ending March 31, 2005, the
Parent will maintain a positive EBITDAR. The requirements


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contained in clauses (a) and (b) are to the effect that EBITDAR shall not be
less than, or (otherwise stated) more negative than, the negative amounts
required therein.

     11. The Borrower and the Guarantors represent and warrant that the
foregoing financial covenants are identical to the financial covenants being put
in place with the Borrower's and Guarantors' existing bank loan facilities.

     12. The Parent represents and warrants that the Note Issuance will be
issued under substantially similar terms as those presented to the Lender in the
summary of terms and conditions of subordinated debt previously provided to the
Lender.

     13. The Borrower and the Guarantors hereby covenant and agree that if the
financial covenants of the existing Southwest Bank of Texas loan facilities are
changed to be more restrictive than the financial covenants set forth herein,
then (i) the Borrower and the Guarantors will promptly notify the Lender, (ii)
the financial covenants set forth herein will automatically be modified to
conform with such more restrictive covenants and (iii) the Borrower and the
Guarantors will execute such documents and instruments as may be reasonably
required by the Lender to evidence such modification of the financial covenants
set forth herein. Upon either the early termination or maturity of the
Guarantors existing Southwest Bank of Texas loan facilities, the Borrower and
the Guarantors hereby covenant and agree that if the financial covenants of the
existing CIT loan facilities (or any successor loan facilities) have been or are
thereafter changed to be more restrictive than the financial covenants set forth
herein, then (i) the Borrower and the Guarantors will promptly notify the
Lender, (ii) the financial covenants set forth herein will automatically be
modified to conform with such more restrictive covenants and (iii) the Borrower
and the Guarantors will execute such documents and instruments as may be
reasonably required by the Lender to evidence such modification of the financial
covenants set forth herein.

     14. It is further understood and agreed by and among the parties hereto
that all terms and conditions of the Loan Agreement, except as herein modified,
shall remain in full force and effect.

     15. This First Amendment may be executed in multiple counterparts, each of
which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

                  [Remainder of page intentionally left blank.]


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     IN WITNESS WHEREOF, the parties hereto have caused this Loan Amendment to
be duly executed as of the day and year first above written.

BORROWER:                                      LENDER:

HORIZON VESSELS INTERNATIONAL, LTD.            BOEING CAPITAL CORPORATION

BY:          /s/  David W. Sharp               BY:
-----------------------------------------         ------------------------------
NAME:           DAVID W. SHARP                 NAME:
TITLE: EXECUTIVE VICE PRESIDENT AND CHIEF      TITLE:
              FINANCIAL OFFICER

GUARANTORS:

HORIZON OFFSHORE, INC.

BY:          /s/  David W. Sharp
-----------------------------------------
NAME:           DAVID W. SHARP
TITLE: EXECUTIVE VICE PRESIDENT AND CHIEF
              FINANCIAL OFFICER

HORIZON VESSELS, INC.

BY:          /s/  David W. Sharp
-----------------------------------------
NAME:           DAVID W. SHARP
TITLE: EXECUTIVE VICE PRESIDENT AND CHIEF
              FINANCIAL OFFICER


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