EXHIBIT 10.19

      AMENDMENT NO. 3

                                       TO

                                 LOAN AGREEMENT

      AMENDMENT NO. 3 ("Amendment No. 3") dated as of November __, 1999 (the
"Amendment Date") to the Loan Agreement dated as of December 30, 1998, as
amended (the "Loan Agreement"), among HORIZON VESSELS, INC., a Delaware
corporation, HORIZON OFFSHORE CONTRACTORS, INC., a Delaware corporation
(together, the "Borrowers"), HORIZON OFFSHORE, INC., a Delaware corporation
(the "Guarantor"), THE CIT GROUP/EQUIPMENT FINANCING, INC., a New York
corporation ("CIT"), HELLER FINANCIAL LEASING, INC., a Delaware corporation,
U.S. BANCORP LEASING & FINANCIAL, an Oregon corporation, SAFECO CREDIT
COMPANY, INC., a Washington corporation, TRANSAMERICA EQUIPMENT FINANCIAL
SERVICE CORPORATION, a Delaware corporation, and PHOENIXCOR, INC., a Delaware
corporation (collectively, the "Original Lenders") and CIT as Agent for the
Original Lenders (the "Agent").

      W I T N E S S E T H:
      - - - - - - - - - -

      WHEREAS, pursuant to the Loan Agreement, the Original Lenders made
available to the Borrowers a loan facility of up to USD 73,800,000, as evidenced
by the amended and restated secured promissory note of the Borrowers dated
January 30, 1999; and

      WHEREAS, the Borrowers wish to acquire the United States flag vessel
ATLANTIC HORIZON (the "New Vessel"); and

      WHEREAS, the Borrowers have requested that the loan facility be increased
up to a maximum amount of USD 83,300,000; and

      WHEREAS, Deutsche Financial Services Corporation, a Nevada corporation
(the "New Lender", and together with the Original Lenders, the "Lenders") wishes
to subscribe to that portion of the Commitment equal to USD 10,000,000; and

      WHEREAS, the parties wish to amend the Loan Agreement to reflect the
foregoing and to amend certain provisions thereof.

      NOW THEREFORE, in consideration of the above recitals and for other good
and valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties agree to amend the Loan Agreement as follows:

      1.    The Definitions of the Loan Agreement are hereby amended as
follows:
<PAGE>
            (a) Each reference in the Loan Agreement to "Lenders" is hereby
      amended to include the New Lender.

            (b)   Each reference in the Loan Agreement to "Amendment
      Documents" is hereby amended to include the Amendment Documents listed
      in Section 4.1 of this Amendment No. 3.

            (c) Each reference in the Loan Agreement to the Note shall refer to
      the Amended and Restated Promissory Note dated the date hereof by the
      Borrowers in favor of the Agent.

            (d)   The definition of "Commitment" is hereby amended to read as
      follows:

            "Commitment" means USD 83,300,000.

      2.    Section 1.3(a) of the Loan Agreement is hereby amended to read as
follows:

      "(a)  The Borrowers shall jointly and severally repay the principal amount
            of the first Advance in eighty-four (84) consecutive monthly
            installments of USD 462,963, the amount of the second Advance in
            eighty-four (84) consecutive monthly installments of USD 46,296, the
            amount of the third Advance in eighty-four (84) consecutive monthly
            installments of USD 127,778, and the amount of the fourth Advance in
            seventy-three (73) consecutive monthly installments of USD 154,490,
            with each such installment to be paid by the Borrowers to the Agent
            on a date commencing on the day which is thirty (30) days after the
            date of such Advance, and on the same day of each month thereafter
            and ending on the Maturity Date (each such date a "Payment Date");
            provided, however, that the final installment for each Advance shall
            be in an amount sufficient to repay all amounts of principal for
            such Advance and, provided further, that the final payment on the
            Maturity Date shall be in an amount sufficient to discharge the
            accrued and unpaid interest and principal in respect of the Note."

      3. The final clause of Article IV of the Loan Agreement (immediately
following Article IV(f)) is hereby amended to read as follows:

            "then the Agent may by written notice to the Borrowers (1)
            immediately terminate the commitment of the Lenders hereunder;
            (2)declare the principal of, and interest accrued to the date of
            such declaration on, the Note together with all other amounts due
            hereunder or under any of the Loan Documents, to be forthwith due
            and payable, whereupon the same shall become forthwith due and
            payable (PROVIDED, HOWEVER, no notice or declaration shall be
            required and such amounts shall be immediately due and payable upon
            the occurrence of an event described

EXHIBIT 10.19
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<PAGE>
            in Article IV(e)(ii) or (iii) hereof) and (3) exercise any remedies
            to which it may be entitled by any Loan Document or by applicable
            law."

      4.    Schedule 1 to the Loan Agreement is hereby replaced with Schedule
1 attached to this Amendment No. 3.

      4.    CONDITIONS PRECEDENT.

      4.1 DOCUMENTS REQUIRED AS CONDITIONS PRECEDENT TO AMENDMENT NO. 3. The
effectiveness of the modifications to the Loan Agreement contemplated by this
Amendment No. 3 is subject to the condition precedent that the Agent shall have
received at or prior to the Amendment Date all of the following, each dated on
or before the Amendment Date and each in form and substance satisfactory to the
Agent and its counsel:

            (a) Each of the following documents (the "Amendment Documents")
      shall have been duly authorized and executed with original counterparts
      thereof delivered to the Agent:

                  (i)   This Amendment No. 3;

                  (ii)  Amended and Restated Promissory Note;

                  (iii) Amendment No. 3 to the United States First Preferred
            Fleet Mortgage;

                  (iv) Amendment No. 3 to Vanuatu First Preferred Fleet
            Mortgage;

                  (v)   Ratification of Guaranty executed by the Guarantor;

                  (vi)  Amendment and Ratification of Security Agreement;

                  (vii) Ratification of Intercreditor Agreement;

                  (viii) Amendment No. 2 to Deed of Covenants; and

                  (ix) such further documents as the Lenders may reasonably
            request.

            (b) The representations and warranties contained in Section 3.1 of
      the Loan Agreement shall be true on the Amendment Date with the same
      effect as though such representations and warranties had been made on and
      as of such date, and no Event of Default specified in Article IV of the
      Loan Agreement and no event which, with the lapse of time or the giving of
      notice and the lapse of time specified in Article IV of the Loan

EXHIBIT 10.19

                                       3
<PAGE>
      Agreement, would become such an Event of Default, shall have occurred and
      be continuing.

      4.2 WAIVER OF CONDITIONS PRECEDENT. All of the conditions precedent
contained in this Section 4 are for the sole benefit of the Agent and the
Lenders and the Agent may waive any of them in its absolute discretion, and on
such conditions as it deems proper.

      5.    REPRESENTATIONS OF THE BORROWERS AND GUARANTOR.  The Borrowers
and the Guarantor represent and warrant that:

            (a) Each of the Borrowers and the Guarantor is a corporation, duly
      organized and validly existing in good standing under the laws of the
      State of Delaware, and has the requisite power and authority (i) to carry
      on its business as presently conducted; and (ii) to enter into and perform
      its obligations under the Amendment Documents.

            (b) The execution, delivery and performance by each of the Borrowers
      and the Guarantor of the Amendment Documents and any other instrument or
      agreement provided for by this Amendment No. 3 to which it is a party,
      have been duly authorized by all necessary corporate action, do not
      require stockholder approval other than such as has been duly obtained or
      given, do not or will not contravene any of the terms of its Certificate
      of Incorporation or Bylaws, and will not violate any provision of law or
      of any order of any court or governmental agency or constitute (with or
      without notice or lapse of time or both) a default under, or result
      (except as contemplated by this Amendment No. 3) in the creation of any
      security interests, lien, charge or encumbrance upon any of its properties
      or assets pursuant to, any agreement, indenture or other instrument to
      which it is a party or by which it may be bound other than is in favor of
      the Agent; the Amendment Documents have been duly executed and delivered
      by the Borrowers and the Guarantor and constitute the respective legal,
      valid and binding agreements, enforceable in accordance with the
      respective terms thereof as to which each of the Borrowers and the
      Guarantor is a party. The enforceability of this Amendment No. 3, however,
      is subject to all applicable bankruptcy, insolvency, reorganization,
      moratorium, and other laws affecting the rights or creditors and to
      general equity principles.

            (c) Except as set forth in the Loan Agreement, there are no suits or
      proceedings pending or to its knowledge threatened against or affecting
      any Borrower or Guarantor which if adversely determined would have a
      material adverse effect upon its business, financial condition or
      operations.

            (d) Other than such as have been obtained, no license, consent or
      approval of any Governmental Agency or other regulatory authority is
      required for the execution, delivery or performance of this Amendment No.
      3 or any other Amendment Document or any instrument contemplated herein or
      therein. The Borrowers are the holder of all

EXHIBIT 10.19

                                       4
<PAGE>
      certificates and authorizations of governmental authorities required by
      law to enable it to engage in the business transacted by them.

      6. EXPENSES. The Borrowers and the Guarantor agree to promptly, whether or
not the modifications to the Loan Agreement contemplated by this Amendment No. 3
become effective, (x) reimburse the Agent for all fees and disbursements of
external counsel to the Agent and all reasonable out of pocket fees and
disbursements of the Agent incurred in connection with the preparation,
execution and delivery of this Amendment No. 3 and all other documents referred
to herein, and all amendments or waivers to or termination of this Amendment No.
3 or any agreement referred to herein; and (y) reimburse the Agent for all fees
and disbursements of internal and external counsel to the Agent and all
reasonable out of pocket fees, disbursements and travel-related expenses of the
Agent incurred in connection with the protection of the rights of the Agent
under this Amendment No. 3 and all other documents referred to herein, whether
by judicial proceedings or otherwise. The obligations of the Borrowers and the
Guarantor under this Section 6 shall survive payment of the Loan.

      7. Wherever and in each such place the term "Loan Agreement" is used
throughout the Loan Agreement, such term shall be read to mean the Loan
Agreement as amended by this Amendment No. 3.

      8.    Except as specifically amended by this Amendment No. 3, all of
the terms and provisions of the Loan Agreement shall remain in full force and
effect.

      9. All capitalized terms used herein but not defined herein shall have the
meanings given to them in the Loan Agreement.

      10.   THIS AMENDMENT NO. 3 TO LOAN AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE
OF NEW YORK.

      IN WITNESS WHEREOF, the parties hereto have duly executed this Amendment
No. 3 to Loan Agreement on the date first written above.

                                   BORROWERS:

                                    HORIZON OFFSHORE CONTRACTORS, INC.


                                    By:____

EXHIBIT 10.19

                                       5
<PAGE>
                                    Name:__
                                    Title:_

                                    HORIZON VESSELS, INC.


                                    By:____
                                    Name:__
                                    Title:_

                                   GUARANTOR:

                                    HORIZON OFFSHORE, INC.


                                    By:____
                                    Name:__
                                    Title:_

                                    LENDERS:

                                    THE CIT GROUP/EQUIPMENT FINANCING, INC.


                                    By:____
                                    Name:__
                                    Title:_

                                    SAFECO CREDIT COMPANY, INC.


                                    By:____
                                    Name:__
                                    Title:_

                                    U.S. BANCORP LEASING & FINANCIAL

EXHIBIT 10.19

                                       6
<PAGE>
                                    By:____
                                    Name:__
                                    Title:_

                                    HELLER FINANCIAL LEASING, INC.


                                    By:____
                                    Name:__
                                    Title:_

                                    TRANSAMERICA EQUIPMENT FINANCIAL SERVICE
                                    CORPORATION

                                    By:____
                                    Name:__
                                    Title:_

                                    PHOENIXCOR, INC.


                                    By:____
                                    Name:__
                                    Title:_

                                    DEUTSCHE FINANCIAL SERVICES CORPORATION


                                    By:____
                                    Name:__
                                    Title:_

                                    AGENT:

                                    THE CIT GROUP/EQUIPMENT FINANCING, INC.


                                    By:____

EXHIBIT 10.19

                                       7
<PAGE>
                                    Name:__
                                    Title:_


EXHIBIT 10.19

                                       8
<PAGE>
      SCHEDULE 1 TO

                                 LOAN AGREEMENT

      LENDER                        PORTION OF COMMITMENT

1.    The CIT Group/Equipment
      Financing, Inc.               USD   23,300,000

2.    Heller Financial
      Leasing, Inc.                 USD   15,000,000

3.    TransAmerica Equipment
      Financial Service Corp.       USD   15,000,000

4.    U. S. Bancorp Leasing
      & Financial                   USD   10,000,000

5.    Safeco Credit Company,
      Inc.                          USD   5,000,000

6.    Phoenixcor, Inc.              USD   5,000,000

7.    Deutsche Financial Services
      Corporation                   USD   10,000,000


EXHIBIT 10.19

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