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                                                                       EXHIBIT 5

                                                                  April 27, 1998




Iridium Operating LLC,
Iridium Capital Corporation,
Iridium Roaming LLC,
Iridium IP LLC,
Iridium Facilities Corporation,
      1575 Eye Street, N.W.,
           Washington, D.C.  20005.

Dear Sirs:

                  In connection with the registration under the Securities Act
of 1933 (the "Act") of (i) $350,000,000 principal amount of [ ]% Senior Notes
due 2005, Series D (the "Notes") of Iridium Operating LLC, a Delaware limited
liability company ("Iridium"), and its wholly-owned subsidiary Iridium Capital
Corporation, a Delaware corporation (together with Iridium, the "Note Issuers"),
and (ii) the Guarantees of the Notes (the "Guarantees") by Iridium Roaming LLC,
a Delaware limited liability company and a wholly-owned subsidiary of Iridium
("Roaming"), Iridium IP LLC, a Delaware limited liability company and a
wholly-owned subsidiary of Iridium ("IP"), and Iridium


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Iridium Operating LLC                                                           
Iridium Capital Corporation
Iridium Roaming LLC
Iridium IP LLC
Iridium Facilities Corporation


Facilities Corporation, a Delaware corporation and a wholly-owned subsidiary of
Iridium ("Facilities", and together with Roaming and IP, the "Guarantor
Subsidiaries"), we, as your counsel, have examined such corporate records,
certificates and other documents, and such questions of law, as we have
considered necessary or appropriate for the purposes of this opinion. The Notes
and the Guarantees are collectively referred to herein as the "Securities".

                  Upon the basis of such examination, we advise you that, in our
opinion, when the Registration Statement has become effective under the Act, the
Indenture relating to the Securities has been duly authorized executed and
delivered, the terms of the Securities and of their issuance and sale have been
duly established in conformity with the Indenture so as not to violate any
applicable law or result in a default under or breach of any agreement or
instrument binding upon any of the Note Issuers or the Guarantor Subsidiaries
and so as to comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over any of the Note Issuers or the
Guarantor Subsidiaries, and the Securities have been duly executed and
authenticated in accordance with the Indenture and issued and sold as
contemplated in the Registration Statement,


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Iridium Operating LLC                                                           
Iridium Capital Corporation
Iridium Roaming LLC
Iridium IP LLC
Iridium Facilities Corporation


(i) the Notes will constitute valid and legally binding obligations of the Note
Issuers, subject to bankruptcy, insolvency, fraudulent transfer, reorganization,
moratorium and similar laws of general applicability relating to or affecting
creditors' rights and to general equity principles, and (ii) the Guarantees will
constitute valid and legally binding obligations of the Guarantor Subsidiaries,
subject to bankruptcy, insolvency, fraudulent transfer, reorganization,
moratorium and similar laws of general applicability relating to or affecting
creditors' rights and to general equity principles.

                  In rendering the foregoing opinion, we are expressing no
opinion as to Federal or state laws relating to fraudulent transfers.

                  The foregoing opinion is limited to the Federal laws of the
United States, the laws of the State of New York and the General Corporation Law
and Limited Liability Company Act of the State of Delaware, and we are
expressing no opinion as to the effect of the laws of any other jurisdiction.

                  We have relied as to certain matters on information obtained
from public officials, officers of the


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Iridium Operating LLC                                                           
Iridium Capital Corporation
Iridium Roaming LLC
Iridium IP LLC
Iridium Facilities Corporation

Note Issuers and Guarantor Subsidiaries and other sources believed by us to be
responsible.
                  We hereby consent to the filing of this opinion as an exhibit
to the Registration Statement and to the refer ence to us under the heading
"Validity of the Securities" in the Prospectus. In giving such consent, we do
not thereby admit that we are in the category of persons whose consent is
required under Section 7 of the Act.

                                                               Very truly yours,