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                                                                 EXHIBIT 10.26.1
                                 AMENDMENT NO. 1
                        CONSENT TO ASSIGNMENT OF CONTRACT


This Amendment No. 1 (the "Amendment") is entered into among Andersen Consulting
LLP, an Illinois limited liability partnership ("Andersen"), Iridium Operating
LLC, a limited liability company duly organized and validly existing under the
laws of the State of Delaware ("Iridium Operating"), (iii) the collateral agent
(the "Existing Collateral Agent") named in the Credit Agreement (the "Existing
Credit Agreement"), dated December 19, 1997, among Iridium Operating, and the
parties name therein and (iv) the collateral agent (the "New Collateral Agent")
to be named in the Senior Secured Credit Agreement (the "New Credit Agreement"),
to be entered into on or about December 22, 1998, among Iridium Operating, The
Chase Manhattan Bank, as administrative agent and as collateral agent, Chase
Securities Inc. and Barclays Bank PLC as global lead arrangers and joint book
managers, Barclays Bank PLC as documentation agent and the Lenders thereunder
(the "Lenders"). Terms used but not defined herein shall have the meanings
assigned to them in the New Credit Agreement.

                                    RECITALS

WHEREAS, pursuant to the Consent to Assignment of Contract (the "Consent") among
Andersen, Iridium Operating and the Existing Collateral Agent, Andersen agreed
to consent to the assignment and pledge of the IBSS Agreement between Iridium
Operating (as successor to Iridium LLC) and Andersen (the "Contract") by Iridium
Operating to the Existing Collateral Agent.

WHEREAS, pursuant to the New Credit Agreement, Iridium Operating has again
agreed to assign and pledge its rights under and to the Contract to the New
Collateral Agent on behalf of the Lenders, and Andersen has agreed to consent to
the assignment and pledge of the Contract by Iridium Operating to the New
Collateral Agent.

WHEREAS, Iridium Operating, Andersen and the Existing Collateral Agent wish to
amend the Consent in certain respects, and to add the New Collateral Agent as a
party thereto. Accordingly, in consideration of the premises and consideration
herein contained, the receipt and sufficiency of which are hereby acknowledged,
the parties hereto hereby agree as follows:

       1. Each reference in the Consent to the "Credit Agreement" or words of
similar import shall be deemed to refer to the New Credit Agreement.


                                 Amendment No. 1

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       2. Each reference in the Consent to the "Security Agreement" or words of
similar import shall be deemed to refer to the Security Agreement to be entered
into on or about December 22, 1998, in accordance with the New Credit Agreement.

       3. Each reference in the Consent to the "Collateral Agent" or words of
similar import shall be deemed to refer to the New Collateral Agent.

       4. Operating hereby agrees to promptly reimburse Andersen for the payment
of, or pay on behalf of Andersen, all taxes (including penalties and interest
thereon) incurred by Andersen in connection with the assignment and pledge by
Operating, of the rights and obligations under the Contract, the exercise of
such pledge by the Collateral Agent and any resulting assumption by the
Collateral Agent or its assignee, provided that Andersen shall use reasonable
efforts to minimize the imposition of taxes in connection with such assignment
and assumption and provided further that such indemnification shall be reduced
by any tax benefits realized by Andersen in connection with the exercise of the
pledge, if any, or any events leading to or resulting in such exercise.

       5. Binding Effect. Except as herein provided, the Consent shall remain
unchanged and in full force and effect.

       6. Entire Agreement. The Consent, as modified by this Amendment,
constitutes the entire agreement of the parties with respect to the subject
matter hereof.

       7. Counterparts. This Amendment may be executed in any number of
counterparts, each of which shall be identical and all of which, when taken
together, shall constitute one and the same instrument, and any of the parties
hereto may execute this Amendment by signing any such counterpart.

       8. Governing Law. This Amendment shall be governed by and construed in
accordance with the law of the State of New York.


                                 Amendment No. 1
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                                      -----------------------
                                      Andersen Consulting LLP


                                 By
                                     -----------------------
                                     Name:
                                     Title:



                                 IRIDIUM OPERATING LLC


                                 By
                                     -----------------------
                                     Name:  Roy Grant
                                     Title: Vice President and
                                            Chief Financial Officer


                                 THE CHASE MANHATTAN BANK
                                     as Existing Collateral Agent


                                 By
                                     -----------------------
                                     Name:
                                     Title:


                                 THE CHASE MANHATTAN BANK
                                     as New Collateral Agent


                                 By
                                     -----------------------
                                     Name:
                                     Title:



                                 Amendment No. 1