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                                                                   EXHIBIT 10.39
                                           (EXHIBIT I-1 TO THE CREDIT AGREEMENT)


                              PROGRESS CERTIFICATE


The Chase Manhattan Bank,
  as Administrative Agent
1 Chase Manhattan Plaza
8th Floor
New York, NY 10017
Attention:  Loan and Agency Services Group



            Reference is made herein to the Credit Agreement (as amended,
supplemented and otherwise modified and in effect from time to time, the "Credit
Agreement") dated as of December 19, 1997 among Iridium Operating LLC, a
Delaware limited liability company (the "Company"), the lenders party thereto,
Chase Securities Inc. and Barclays Capital, the investment banking division of
Barclays Bank PLC, as Global Arrangers, The Chase Manhattan Bank, as
Administrative Agent and as Collateral Agent, and Barclays Bank PLC, as
Documentation Agent. Capitalized terms used but not defined herein have the
meanings given to such terms in the Credit Agreement. This Certificate is being
delivered to the Administrative Agent pursuant to Article IV of the Credit
Agreement.

            In connection with the transfer of funds from the Pre-Funding
Account to the General Receipt & Disbursement Account (the "Borrowing Date"),
the undersigned hereby certifies that:

            1. Commercial Activation is expected to occur not later than
      December 23, 1998.

            2. Each of the technical requirements specified in Annex A to
      Appendix 2 to the Credit Agreement that is required to be satisfied for
      Stage 1 (as identified in said Annex A) on or prior to the Borrowing Date
      has been, and remains, substantially completed as of the Borrowing Date.
      Prior to the date of this Certificate, Motorola delivered to the
      Independent Technical Advisor and the Company its statement(s) pursuant to
      Section 5.05 of the Motorola Consent that certain of such technical
      requirements have been satisfactorily completed, and the Company has no
      reason to believe that such statements are not true.

            3. (a) Each of the regulatory requirements specified in Annex A to
      Appendix 2 to the Credit Agreement that is required to be satisfied for
      Stage 1 (as referred to in said Annex A) on or prior to the Borrowing Date
      has been, and remains, satisfied as of the Borrowing Date. Set forth in
      Schedule I to this Progress Certificate is, as of the Borrowing Date, (i)
      a list of countries for which L-based spectrum licenses ("L-band
      Licenses") for the Project have been obtained (each a "L-band License
      Country") and for which a legal opinion satisfying the requirement under
      paragraph 4(b) below is attached, (ii) a list of service provider
      agreements which have been entered into and continue in
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                                      - 2 -


      effect, (iii) a list of roaming agreements which have been entered into
      and continue in effect (in the case of the agreements referred to in
      clauses (ii) and (iii), specifying the date and counterparty or
      counterparties of each such agreement and the jurisdiction), (iv) a list
      of non-gateway countries for which agreements are in place for the
      interconnection of the IRIDIUM System with the PSTN in that country and
      (v) a list of countries for which the existing service provider agreements
      and/or roaming agreements provide national sales distribution for IRIDIUM
      services.

                  (b) Attached hereto are copies of the opinions of legal
      counsel for each for each L-band License Country (other than those
      previously delivered to the Administrative Agent with a Progress
      Certificate) confirming, each as of a recent date, that the L-band License
      in such country has been obtained. The Company is not aware of, nor does
      it have any reason to believe that there has occurred, any adverse change
      in the status of any such L-band License.

                  (c) As shown on Schedule I to this Progress Certificate, as of
      the Borrowing Date, (i) the L-band License Countries constitute countries
      projected to generate at least 33% of the Company's revenues as set forth
      in the Iridium Financial Projections, (ii) not less than 75% of the
      revenues referred to in sub-clause (i) above are projected to be from
      countries for which service provider agreements and/or roaming agreements
      providing for a national sales distribution for the IRIDIUM services (in
      compliance with the requirements set forth in Attachment 3 to Annex A to
      Appendix 2) are currently in effect.

            4. The Company is in compliance with its obligations under Section
      8.04 of the Credit Agreement as of the Borrowing Date. Set forth in
      Schedule II to this Project Certificate is a list of the sources of
      funding currently committed or available to the Company that satisfy the
      requirements of said Section 8.04.
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                                      - 3 -


            IN WITNESS WHEREOF, the Company has caused this Progress Certificate
to be executed by a Responsible Officer this ____ day of January, 1998.


                                    IRIDIUM OPERATING LLC


                                    By:____________________________________
   4
                                                                      Schedule I
                                                         to Progress Certificate


                              Regulatory Conditions


1.  Countries with L-band spectrum licenses

            Country           % of Iridium Business
                              Plan Revenues









              -----           -------------
      Totals:                                   %
   5
                                      - 2 -                           Schedule I
                                                         to Progress Certificate


2.  Service Provider Agreements


      Country           Counterparty            Date
      -------           ------------            ----







      TOTAL NUMBER OF SERVICE PROVIDER AGREEMENTS:
   6
                                      - 3 -                           Schedule I
                                                       to Progress Certificate





3.  Roaming Agreements


      Country           Counterparty            Date
      -------           ------------            ----







      TOTAL NUMBER OF ROAMING AGREEMENTS:
   7
                                      - 4 -                           Schedule I
                                                         to Progress Certificate
    

4.  PSTN Access in Non-Gateway Countries


      Country





      TOTAL:  ______
   8
                                      - 5 -                           Schedule I
                                                         to Progress Certificate




5.  Countries with National Sales Distribution Network


      Country






      TOTAL:  ______
   9
                                                                     Schedule II
                                                         to Progress Certificate


                                 Funding Sources


                        [To be completed by the Company]