EXHIBIT 10.94

                                 AMENDMENT NO. 4
                    TO AMENDED & RESTATED SECURITY AGREEMENT

This AMENDMENT NO. 4 TO AMENDED & RESTATED SECURITY AGREEMENT (this
"AMENDMENT"), is made effective as of March 31, 2008 (the "EFFECTIVE DATE"), by
and between U.S. HELICOPTER CORPORATION, a Delaware corporation with its
principal place of business located at 6 East River Piers, Suite 216, Downtown
Manhattan Heliport, New York, New York 10004 (the "COMPANY") and YA GLOBAL
INVESTMENTS, L.P. (the "SECURED PARTY") with reference to the following
recitals:

A. Secured Party and the Company entered into that certain Amended & Restated
Security Agreement, dated March 30, 2007, as amended by that certain Amendment
No. 1 to Amended & Restated Security Agreement as of May 14, 2007, that certain
Amendment No. 2 to Amended & Restated Security Agreement as of August 24, 2007
and that certain Amendment No. 3 to Amended & Restated Security Agreement as of
March 14, 2008 (as amended, the "MASTER AGREEMENT").

B. Contemporaneously with the execution of this Amendment, the Secured Party and
the Company are entering into a Securities Purchase Agreement (the "SPA")
pursuant to which the Company shall issue and sell to the Secured Party
additional secured debentures (the "ADDITIONAL DEBENTURES").

C. To induce the Secured Party to execute and deliver the SPA and purchase the
Additional Debentures, the Company has agreed to amend the Master Agreement to
provide certain amendments to the Master Agreement to specifically include the
Additional Debentures as part of the "Obligations" as defined in the Master
Agreement.

FOR GOOD AND VALUABLE CONSIDERATION, the receipt and sufficiency of which is
hereby acknowledged, Secured Party and the Company agree as follows:

1. Convertible Debentures. The Definition of the term "Convertible Debentures"
as used in the Master Agreement shall hereinafter include the Additional
Debentures.

2. Transaction Documents. The Definition of the term "Transaction Documents" as
used in the Master Agreement shall hereinafter include the Additional Debentures
and the SPA entered into on the date hereof.

3. Obligations Secured. The definition of the term "Obligations" as used in the
Master Agreement shall include all the obligations of the Company to the Secured
Party under the Additional Debentures.

4. Financing Statements. The Company hereby irrevocably authorize the Secured
Party, at any time and from time to time to file in any filing office in any
jurisdiction any initial financing statements and amendments thereto that (a)
described the Pledged Property and (b) contains any other information required
by Part 5 of Article 9 of the UCC for the sufficiency or filing office
acceptance of any financing statement or amendment, including (i) the type of
organization and any organization identification number issued to the Company,
and (ii) in the case of a financing statement filed as a fixture filing, a
sufficient description of real property to which the Pledged Property relates.
The Company agrees to furnish any such information to the Secured Party promptly
upon request. The Company also hereby ratifies its authorization for the Secured
Party to have filed in any jurisdiction any initial financing statements or
amendments thereto if filed prior to the date hereof. The Company acknowledges
that it is not authorized to file any financing statement or amendment or
termination statement with respect to any financing statement without the prior
written consent of the Secured Party and agree that it will not do so without
the prior written consent of the Secured Party. -

5. Simultaneously with the execution and delivery of this Agreement, the Company
shall make, execute, acknowledge, file, record and deliver to the Secured Party
such documents, instruments, and agreements, including, without limitation,
financing statements, certificates, affidavits and forms as may, in the Secured
Party's reasonable judgment, be necessary to effectuate, complete or perfect, or
to continue and preserve, the security interest of the Secured Party in the
Pledged Property.

6. Definitions. Capitalized terms not otherwise defined herein shall have the
meaning ascribed to them under the Master Agreement.
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7. Non-Impairment. Except as expressly modified herein, the Master Agreement
shall continue in full force and effect, and the parties hereby reinstate and
reaffirm the Master Agreement as modified herein.

8. Inconsistencies. In the event of any inconsistency, ambiguity or conflict
between the terms and provisions of this Amendment and the terms and provisions
of the Master Agreement, the terms and provisions of this Amendment shall
control.

9. Counterparts. This Amendment may be executed in any number of counterparts,
each of which when executed will be deemed an original and all of which, taken
together, well be deemed to be one and the same instrument.

                   REMAINDER OF PAGE INTENTIONALLY LEFT BLANK

      IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the date first above written.

                                           COMPANY:
                                           U.S. HELICOPTER CORPORATION

                                           By: /s/ John G. Murphy
                                               ------------------
                                           John G. Murphy
                                           Chief Executive Officer and President


                                           SECURED PARTY:
                                           YA GLOBAL INVESTMENTS, L.P.

                                           By: Yorkville Advisors, LLC
                                           Its: Investment Manager

                                           By: /s/ Mark Angelo
                                               ------------------
                                           Name: Mark Angelo
                                           Title: Portfolio Manager


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