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                                                                    EXHIBIT 10.3

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                    ASSIGNMENT OF EARNINGS AND CHARTERPARTIES

                                   in favor of

                     MANUFACTURERS AND TRADERS TRUST COMPANY

                                   as Assignee

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                                  [DATE], 2004

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                    ASSIGNMENT OF EARNINGS AND CHARTERPARTIES

            THIS ASSIGNMENT is made this [DAY] day of [MONTH], 2004, from
[ASSIGNOR], a company organized and existing under the laws of the [JURISDICTION
OF INCORPORATION], with offices at [ADDRESS] (the "Assignor"), in favor of
MANUFACTURERS AND TRADERS TRUST COMPANY, a New York banking corporation, with
offices at 25 South Charles Street, Baltimore, Maryland, as trustee pursuant to
the Indenture referred to in Recital B hereto (the "Assignee").

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

WHEREAS:

            (A)   The Assignor is the sole, legal and beneficial owner of the
whole of [each of] the [NATIONALITY] flag vessel[s] listed on Schedule 1 hereto
(the ["Vessels", and each a] "Vessel");

            (B)   Pursuant to an indenture dated as of November 24, 2004, by
and among Ultrapetrol (Bahamas) Limited, as issuer (the "Company"), the
Guarantors party thereto (the "Guarantors"), the Pledgors party thereto (the
"Pledgors") and the Assignee as trustee, (as amended or supplemented from time
to time, the "Indenture"), the Company issued its 9% First Preferred Ship
Mortgage Notes due 2014 (the "Securities") in the aggregate principal amount of
One Hundred Eighty Million United States Dollars (US$180,000,000), the proceeds
of which have been used to repay the Company's 10 1/2% First Preferred Ship
Mortgage Notes dues 2008, to refinance the acquisition cost of other vessels
owned by the Guarantors, and for general corporate purposes;

            (C)   By the Indenture, the Guarantors [(including the Assignor)],
have jointly and severally guaranteed, upon the terms and conditions contained
therein, the punctual payment, performance and observance when due of the
obligations of the Company under and in connection with the Securities,
including, but not limited to, the Company's obligation to pay the principal of,
and premium and interest on, the Securities as provided in the Indenture and the
Securities;

            (D)   By the Security Agreements (other than this Assignment), the
Guarantors [(including the Assignor)] and the Pledgors [(including the
Assignor)] have, upon the terms and conditions contained therein, pledged
certain assets held by them, including the Vessel[s], and assigned certain
insurances obtained by them, to secure the punctual payment, performance and
observance when due of the obligations of the Company under and in connection
with the Indenture and Securities, including, but not limited to, the Company's
obligation to pay the principal of, and premium and interest on, the Securities
as provided in the Indenture and the Securities; and

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            (E)   The Assignor has agreed to grant this Assignment to secure its
and the Company's obligations under the Indenture, and in order to secure the
prompt and due payment to the Trustee of any and all sums which may be or become
due to the Trustee and/or the Securityholders from the Assignor under or
pursuant to the Indenture and also to secure the exact performance and
observance and compliance with all and any of the covenants and agreements and
terms and conditions contained in the Indenture,

            NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged by the Assignor:

            1.    Defined Terms. Unless otherwise defined herein, terms defined
in the Indenture shall have the same meanings when used herein.

            2.    Grant of Security. As security for all Obligations of the
Assignor, the [other] Subsidiary Guarantors and the Company pursuant to the
Indenture and the other Security Agreements, and in consideration of One Dollar
($1) lawful money of the United States of America, and other good and valuable
consideration, the receipt of which is hereby acknowledged, the Assignor, as
legal and beneficial owner, does hereby grant, sell, convey, assign, transfer
and set over unto the Assignee, for the benefit of the Assignee and its
successors and assigns, and does hereby grant the Assignee a security interest
in, all of the Assignor's right, title and interest in and to (i) any charter or
other contract entered into by the Assignor in respect of [the/any] Vessel; (ii)
all earnings of the Vessel[s], including, but not limited to, all moneys and
claims for moneys due and to become due thereto, whether as charter hire,
freights, passage moneys, indemnities, payments or otherwise, under, and all
claims for damages arising out of any breach of (or payment for variation or
termination), any charter or any other bareboat, time or voyage charter,
contract of affreightment or other contract for the use or employment of
[the/any] Vessel and operations of every kind whatsoever of [the/any] Vessel,
(iii) all remuneration for salvage and towage services, demurrage and detention
moneys and any other earnings whatsoever due or to become due to the Assignor
arising from the use or employment of [the/any] Vessel, (iv) all moneys or other
compensation payable by reason of requisition for title or for hire or other
compulsory acquisition of [the/any] Vessel and all claims for damages in respect
of the actual or constructive total loss of [the/any] Vessel, and (v) all
proceeds of all of the foregoing (herein called "Earnings").

            3.    Occurrences following Default. The Assignor hereby further
covenants and agrees that upon the occurrence of a Default or an Event of
Default (a) it will have all the Earnings and other freights, hire and other
monies hereby assigned paid over directly to the Assignee, (b) will procure that
notice of this Assignment in substantially the form of Exhibit 1 attached hereto
and a letter of instructions shall be duly given to each person who becomes
party to any charter or contract of affreightment entered into with the Assignor
in respect of [the/any] Vessel or to any Person who may receive any earnings and
monies hereby assigned, (c) it will instruct each such person to provide consent
where the consent of any such person is required pursuant to any charter or
contract of affreightment assigned hereby, and (d) it will instruct such

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person to acknowledge directly to the Assignee receipt of the Assignor's
notification and instructions.

            4.    Performance under Charters; No Duty of Inquiry. The Assignor
hereby undertakes that, notwithstanding the assignment herein contained, it
shall punctually perform all its obligations under all charters and contracts
pertaining to [the/each] Vessel to which it is a party. It is hereby expressly
agreed that, anything contained herein to the contrary notwithstanding, the
Assignor shall remain liable under all charters and contracts pertaining to
[the/each] Vessel to which it is a party to perform the obligations assumed by
it thereunder, and the Assignee shall have no obligation or liability under any
such charter or contract by reason of or arising out of the assignment contained
herein, nor shall the Assignee be required to assume or be obligated in any
manner to perform or fulfill any obligation of the Assignor under or pursuant to
any such charter or contract or to make any payment or make any inquiry as to
the nature or sufficiency of any payment received by the Assignee, or, unless
and until indemnified to its satisfaction, to present or file any claim or to
take any other action to collect or enforce the payment of any amounts which may
have been assigned to it or to which it may be entitled hereunder or pursuant
hereto at any time or times.

            5.    Requisition. The Assignor shall promptly notify the Assignee
in writing of the commencement and termination of any period during which
[the/any] Vessel may be requisitioned.

            6.    Employment of Vessel[s]. The Assignor hereby further covenants
and undertakes promptly to furnish the Assignee with all such information as it
may from time to time require regarding the employment, position and engagements
of [the/any] Vessel.

            7.    Negative Pledge. The Assignor does hereby warrant and
represent that it has not assigned or pledged, and hereby covenants that it will
not assign or pledge so long as this Assignment shall remain in effect, any of
its right, title or interest in the whole or any part of the Earnings and other
moneys and claims hereby assigned to anyone other than the Assignee, and it will
not take or omit to take any action, the taking or omission of which might
result in an alteration or impairment of the rights hereby assigned or any of
the rights created in this Assignment; and the Assignor does hereby irrevocably
appoint and constitute the Assignee as the Assignor's true and lawful
attorney-in-fact with full power (in the name of the Assignor or otherwise)
should an Event of Default have occurred and be continuing to ask, require,
demand, receive, compound and give acquittance for any and all moneys and claims
for moneys assigned hereby, to endorse any checks or other instruments or orders
in connection therewith, to file any claims or take any action or institute any
proceedings which the Assignee may deem to be necessary or advisable in the
premises and to file any and all Uniform Commercial Code financing statements or
renewals thereof in connection with this Assignment which the Assignee may deem
to be necessary or advisable in order to perfect or maintain the security
interest granted hereby.

            8.    Application of Proceeds. All moneys collected or received from
time to time by the Assignee pursuant to this Assignment shall be dealt with as
provided in the Indenture.

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            9.    Further Assurances. The Assignor agrees that at any time and
from time to time, upon the written request of the Assignee, the Assignor will
promptly and duly execute and deliver any and all such further instruments and
documents as the Assignee may deem desirable in obtaining the full benefits of
this Assignment and of the rights and powers herein granted.

            10.   Remedies Cumulative and Not Exclusive; No Waiver. Each and
every right, power and remedy herein given to the Assignee shall be cumulative
and shall be in addition to every other right, power and remedy of the Assignee
now or hereafter existing at law, in equity or by statute, and each and every
right, power and remedy, whether herein given or otherwise existing, may be
exercised from time to time, in whole or in part, and as often and in such order
as may be deemed expedient by the Assignee, and the exercise or the beginning of
the exercise of any right, power or remedy shall not be construed to be a waiver
of the right to exercise at the same time or thereafter any other right, power
or remedy. No delay or omission by the Assignee in the exercise of any right or
power or in the pursuance of any remedy accruing upon any breach or default by
the Company or the Assignor or any other Guarantor or Pledgor shall impair any
such right, power or remedy or be construed to be a waiver of any such right,
power or remedy or to be an acquiescence therein; nor shall the acceptance by
the Assignee of any security or of any payment of or on account of any of the
amounts due from the Company or the Assignor or any other Guarantor or Pledgor
to the Assignee and maturing after any breach or default or of any payment on
account of any past breach or default be construed to be a waiver of any right
to take advantage of any future breach or default or of any past breach or
default not completely cured thereby.

            11.   Invalidity. If any provision of this Assignment shall at any
time for any reason be declared invalid, void or otherwise inoperative by a
court of competent jurisdiction, such declaration or decision shall not affect
the validity of any other provision or provisions of this Assignment, or the
validity of this Assignment as a whole, which shall remain in full force and
effect. In the event that it should transpire that by reason of any law or
regulation, or by reason of a ruling of any court, or by any other reason
whatsoever, the assignment herein contained is either wholly or partly
defective, the Assignor hereby undertakes to furnish the Assignee with an
alternative assignment or alternative security and/or to do all such other acts
as, in the sole opinion of the Assignee, shall be required in order to ensure
and give effect to the full intent of this Assignment. The powers and
authorities granted to the Assignee and its successors or assigns herein have
been given for valuable consideration and are hereby declared to be irrevocable.

            12.   Continuing Security. It is declared and agreed that the
security created by this Assignment shall be held by the Assignee as a
continuing security for the payment of all moneys which may at any time and from
time to time be or become payable by the Assignor or the Company pursuant to the
Indenture and that the security so created shall not be satisfied by an
intermediate payment or satisfaction of any part of the amount hereby secured
and that the security so created shall be in addition to and shall not in any
way be prejudiced or affected by any collateral or other security now or
hereafter held by the Assignee for all or any part of the moneys hereby secured.

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            13.   Waiver; Amendment. None of the terms and conditions of this
Assignment may be changed, waived, modified or varied in any manner whatsoever
unless in writing duly signed by the Assignee and the Assignor.

            14.   Termination. If the Assignor shall pay and discharge all of
its obligations under or in connection with the Indenture or is released
therefrom in accordance with the terms thereof, all of the right, title and
interest herein assigned shall revert to the Assignor and this Assignment shall
terminate.

            15.   WAIVER OF JURY TRIAL. EACH OF THE ASSIGNOR, AND BY ITS
ACCEPTANCE HEREOF, THE ASSIGNEE, HEREBY WAIVES TRIAL BY JURY IN ANY ACTION,
PROCEEDING OR COUNTERCLAIM BROUGHT BY ANY PARTY HERETO OR ANY BENEFICIARY HEREOF
ON ANY MATTER WHATSOEVER ARISING OUT OF OR IN ANY WAY CONNECTED WITH THIS
ASSIGNMENT, THE INDENTURE OR THE SECURITY AGREEEMENTS TO WHICH THEY ARE PARTY
THEREIN DESCRIBED, ANY AMENDMENTS THERETO, OR THE TRANSACTIONS CONTEMPLATED
HEREBY OR THEREBY.

            16.   Notices. Notices and other communications hereunder shall be
in writing and may be sent by facsimile as follows:

If to the Assignor:      [ASSIGNOR]
                         [ADDRESS]
                         Attention: [NAME].
                         Facsimile: [NUMBER]

with copy to:            Seward & Kissel LLP
                         One Battery Park Plaza
                         New York, New York 10004
                         Attention: Lawrence Rutkowski, Esq.
                         Facsimile: 212-480-8421

If to the Assignee:      Manufacturers and Traders Trust Company
                         Corporate Trust Department
                         Mail Code 101-591
                         25 South Charles Street
                         Baltimore, Maryland 21201-1643
                         Attention: Robert D. Brown
                         Facsimile: 410-244-4236

With copy to:            Ober, Kaler, Grimes & Shriver
                         120 East Baltimore Street
                         Baltimore, Maryland 21202
                         Attention: Patrick Cameron, Esq.
                         Facsimile: 443-263-7540

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or to such other address as either party shall from time to time specify in
writing to the other. Any notice sent by facsimile shall be confirmed by letter
dispatched as soon as practicable thereafter.

            Every notice or other communication shall, except so far as
otherwise expressly provided by this Assignment, be deemed to have been received
(provided that it is received prior to 2 p.m. New York time; otherwise it shall
be deemed to have been received on the next following Business Day) in the case
of a facsimile on the date of dispatch thereof (provided further that if the
date of dispatch is not a Business Day in the locality of the party to whom such
notice or demand is sent, it shall be deemed to have been received on the next
following Business Day in such locality), and in the case of a letter, at the
time of receipt thereof.

            17.   Governing Law. This Assignment shall be governed by and
construed in accordance with the laws of the State of New York.

            18.   Headings. In this Assignment, Section headings are inserted
for convenience of reference only and shall be ignored in the interpretation
hereof.

            IN WITNESS WHEREOF, the Assignor has caused this Assignment to be
executed on the day and year first above written.

                                                    By__________________________
                                                    [NAME]
                                                    [TITLE]

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                                   SCHEDULE 1

<TABLE>
<CAPTION>
                Official                                              Gross          Net
Vessel Name      Number         Length     Breadth      Depth          Tons          Tons
-----------     --------        ------     -------      -----         -----          ----
                                 mts         mts         mts
<S>             <C>             <C>        <C>          <C>           <C>            <C>
</TABLE>

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                                                                       EXHIBIT 1

                           EARNINGS ASSIGNMENT NOTICE

TO:

TAKE NOTICE:

            (a)   that by an Assignment of Earnings dated the [DAY] day of
[MONTH], 2004 made by us (the "Assignor") to MANUFACTURERS AND TRADERS TRUST
COMPANY (the "Assignee"), we, the owner of the [NATIONALITY] flag vessels
[VESSEL NAME], Provisional Patente No. [NUMBER] (the "Vessels"), have assigned
to the Assignee as from the date thereof all our right, title and interest in
and to:

                  (i)   any moneys whatsoever payable to us under any bareboat,
                        time or voyage charter, contract of affreightment or
                        other contract for the use or employment of the Vessels,
                        all freight, hires, passage monies and all other rights
                        and benefits whatsoever accruing to us thereunder,
                        including (but without prejudice to the generality of
                        the foregoing) all claims for damages in respect of any
                        breach by any charterer or other party thereto of any
                        such bareboat, time or voyage charter, contract of
                        affreightment or other contract for the use or
                        employment of the Vessels; and

                  (ii)  all freights, passage moneys, hire moneys or other
                        compensation payable to us in the event of the
                        requisition of the Vessels for title or hire,
                        remuneration for salvage and towage services, demurrage
                        and detention moneys and any other earnings whatsoever
                        due or to become due to us arising from the use or
                        employment of the Vessels;

 as security for that indenture dated as of November 24, 2004, (as at any time
 amended or modified, the "Indenture") among the Assignor, certain other
 Guarantors named therein, the Pledgors named therein, the Assignee and
 Ultrapetrol (Bahamas) Limited.

<PAGE>

            (b)   that you are hereby irrevocably authorized and instructed to
pay as from the date hereof all of such aforesaid moneys to the Assignee, for
the account of Ultrapetrol (Bahamas) Limited (Account No. [NUMBER]) at the above
address of the Assignee (or at such other place as the Assignee may direct).

DATED THIS [DAY] day of [MONTH], 2004

                                                  By____________________________
                                                   Name:
                                                   Title:

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