SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-Q
             QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                  For the quarterly period ended March 31, 1998
                         Commission file number 0-23044

                      AMERICAN MOBILE SATELLITE CORPORATION
             (Exact name of registrant as specified in its charter)

                           DELAWARE          93-0976127
                     (State or other       (I.R.S. Employer
                     jurisdiction of      Identification No.)
                     incorporation or
                      organization)

                10802 Parkridge Boulevard
                        Reston, VA            20191-5416
                  (Address of principal       (Zip Code)
                    executive offices)

                                 (703) 758-6000
                         (Registrant's telephone number,
                              including area code)


     Indicate  by check mark  whether the  registrant  (1) has filed all reports
required to be filed by Section 13 or 15(d) of the  Securities  Exchange  Act of
1934  during  the  preceding  12 months  (or for such  shorter  period  that the
registrant  was  required to file such  report(s)),  and (2) has been subject to
such filing requirements for the past 90 days. Yes X No

     Number of shares of Common Stock outstanding at April 30, 1998: 30,582,782









                          PART I-FINANCIAL INFORMATION

                          Item 1. Financial Statements

             AMERICAN MOBILE SATELLITE CORPORATION AND SUBSIDIARIES
                    CONSOLIDATED CONDENSED STATEMENTS OF LOSS
                      (in thousands, except per share data)
                                   (Unaudited)



                                                             1998          1997
                                                             ----          ----
REVENUES
                                                                    
         Services                                          $6,418        $4,153
         Sales of equipment                                 3,604         4,532
                                                           ------        ------

         Total Revenues                                    10,022         8,685

COSTS AND EXPENSES:
         Cost of service and operations                     7,728         8,873
         Cost of equipment sold                             3,881         5,442
         Sales and advertising                              3,022         3,221
         General and administrative                         3,631         4,868
         Depreciation and amortization                     10,163         9,937
                                                           ------         -----

         Operating Loss                                   (18,403)      (23,656)

INTEREST EXPENSE                                           (6,638)       (4,370)
INTEREST AND OTHER  INCOME                                    141           945
EQUITY IN LOSS OF AMRC                                       (342)           --
                                                           ------        ------

NET LOSS                                                 ($25,242)     ($27,081)
                                                         =========     =========

BASIC AND DILUTED LOSS PER SHARE OF COMMON STOCK           ($1.00)       ($1.08)


WEIGHTED-AVERAGE COMMON SHARES                             25,241        25,109
         OUTSTANDING DURING THE PERIOD (000's)

See notes to consolidated condensed financial statements.







                          PART I-FINANCIAL INFORMATION
                    Item 1. Financial Statements (continued)
             AMERICAN MOBILE SATELLITE CORPORATION AND SUBSIDIARIES
                      CONSOLIDATED CONDENSED BALANCE SHEETS
                                 (In thousands)
                                   (Unaudited)



                                                       March 31,    December 31,

ASSETS                                                     1998         1997
                                                           ----         ----

CURRENT ASSETS:
                                                                   
  Cash and cash equivalents                               $21,279       $2,106
  Inventory                                                38,554       40,321
  Accounts receivable-trade, net                           11,477        8,140
  Restricted cash-current portion                          41,038          --
  Prepaid in-orbit insurance                                2,889        4,564
  Other current assets                                     21,288        9,608
                                                          -------       ------
  Total current assets                                    136,525       64,739

PROPERTY AND EQUIPMENT - NET                              264,261      233,174

GOODWILL                                                   67,616           --

DEFERRED CHARGES AND OTHER ASSETS-NET                      34,164       13,534

RESTRICTED CASH - NON-CURRENT                              82,962           --
                                                          -------      -------

  Total assets                                           $585,528     $311,447
                                                         ========     ========

LIABILITIES AND STOCKHOLDERS' EQUITY

CURRENT LIABILITIES:                                          
  Accounts payable and accrued expenses                    28,042      $35,861
  Obligations under capital leases due within one year      4,133          798
  Current portion of long-term debt                        21,932       15,254
  Other current liabilities                                 7,626        7,520
                                                          -------      -------
  Total current liabilities                                61,733       59,433

LONG-TERM LIABILITIES:
  Obligations under Bank Financing                        100,000      198,000
  Obligations under Senior Notes, net                     326,510           --
  Capital lease obligations                                12,005        3,147
  Net assets acquired in excess of purchase price           2,550        2,725
  Other long-term debt                                      1,126        1,364
  Other long-term liabilities                                 610          647
                                                          -------      -------

  Total long-term liabilities                             442,801      205,883
                                                          -------      -------

  Total liabilities                                       504,534      265,316
                                                          -------      -------

STOCKHOLDERS' EQUITY:
  Preferred Stock, par value $0.01:   no shares issued         --          --
  Common Stock, voting, par value $0.01                       317          252
  Additional paid-in capital                              501,757      451,892
  Common Stock purchase warrants                           62,547       36,338
  Unamortized guarantee warrants                          (39,621)     (23,586)
  Retained loss                                          (444,006)    (418,765)
                                                         ---------    ---------
  Total stockholders' equity                               80,994       46,131
                                                         ---------    ---------

  Total liabilities and stockholders' equity             $585,528     $311,447
                                                         ========     ========

See notes to consolidated condensed financial statements.









                          PART I-FINANCIAL INFORMATION

                    Item 1. Financial Statements (continued)

             AMERICAN MOBILE SATELLITE CORPORATION AND SUBSIDIARIES
                 CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS
                                 (in thousands)
                                   (Unaudited)




                                                                         Three Months Ended
                                                                               March 31
                                                                      ------------------------

                                                                            1998       1997
                                                                            ----       ----

CASH FLOWS FROM OPERATING ACTIVITIES:
                                                                                     
Net loss                                                                 ($25,242) ($27,081)  
Adjustments to reconcile net loss to net cash used
in operating activities:
  Amortization of guarantee warrants, debt discount and issuance costs      2,524     1,754
  Depreciation and amortization                                            10,163     9,937
  Equity in loss from AMRC                                                    342        --
  Changes in assets and liabilities:
     Inventory                                                              1,986    (3,483)
     Prepaid in-orbit insurance                                             1,675     1,693
     Trade accounts receivable                                              3,744    (1,480)
     Other current assets                                                    (661)    1,051
     Accounts payable and accrued expenses                                (12,197)   (9,070)
     Deferred trade payables                                                6,436        --
     Deferred items - net                                                     293       (37)
                                                                          --------  --------
Net cash used in operating activities                                     (10,937)  (26,716)

CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property and equipment                                        (1,126)   (3,574)
Acquisition of ARDIS                                                      (51,382)       --
Purchase of restricted cash securities                                   (123,000)       --
Purchase of interest swap agreement                                       (17,892)       --
Investment in AMRC                                                             --    (3,000)
                                                                         ---------   -------
Net cash used in investing activities                                    (193,400)   (6,574)

CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of Common Stock                                        103       141
Proceeds from issuance of Common Stock of AMRC                                 --     1,500
Principal payments under capital leases                                      (135)     (952)
Proceeds from Bank Financing                                                2,000    35,000
Repayment of Bank Financing                                              (100,000)       --
Proceeds from bridge financing                                             10,000        --
Repayment of bridge financing                                             (10,000)       --
Proceeds from Senior Notes and Warrants                                   335,000        --
Payments on long-term debt                                                     --    (3,000)
Debt issuance costs                                                       (13,458)       (9)
                                                                          --------   -------
Net cash provided by financing activities                                 223,510    32,680


Net increase (decrease) in cash and cash equivalents                       19,173      (610)


CASH AND CASH EQUIVALENTS, beginning of period                              2,106     2,182
                                                                           ------    ------


CASH AND CASH EQUIVALENTS, end of period                                  $21,279    $1,572
                                                                          =======   =======


See notes to consolidated condensed financial statements.










                          PART I-FINANCIAL INFORMATION

                    Item 1. Financial Statements (continued)
             AMERICAN MOBILE SATELLITE CORPORATION AND SUBSIDIARIES
              NOTES TO CONSOLIDATED CONDENSED FINANCIAL STATEMENTS

                                 March 31, 1998
                                   (Unaudited)


1. Organization and Business
- ----------------------------

American Mobile Satellite Corporation (with its subsidiaries,  "American Mobile"
or the  "Company")  was  incorporated  on May 3, 1988,  by eight of the  initial
applicants for the mobile satellite services license,  following a determination
by the Federal Communications  Commission ("FCC") that the public interest would
be best served by granting the license to a consortium of all willing, qualified
applicants.  The FCC has authorized  American Mobile to construct,  launch,  and
operate a mobile satellite services system (the "Satellite Network ") to provide
a full range of mobile voice and data  services via  satellite to land,  air and
sea-based  customers  in a service area  consisting  of the  continental  United
States,  Alaska,  Hawaii,  Puerto Rico, the U.S.  Virgin Islands,  U.S.  coastal
waters,  international  waters and airspace and any foreign  territory where the
local  government  has  authorized  the  provision  of  service.  In March 1991,
American Mobile Satellite Corporation  transferred the mobile satellite services
license ("MSS license") to a wholly owned subsidiary, American Mobile Subsidiary
Corporation  ("AMSC  Subsidiary").  On April 7, 1995,  the Company  successfully
launched its first satellite ("MSAT-2"), from Cape Canaveral, Florida.

On December  31,  1997,  the Company  (through  its  newly-formed,  wholly-owned
subsidiary, AMSC Acquisition Company, Inc. ("Acquisition Company"), entered into
a Stock  Purchase  Agreement  (the "Purchase  Agreement")  with  Motorola,  Inc.
("Motorola"),   for  the  acquisition  (the   "Acquisition")  of  ARDIS  Company
("ARDIS"),  a  wholly-owned  subsidiary  of  Motorola  that owns and  operates a
two-way wireless data communications  network. On March 3, 1998, the FCC granted
consent to consummate the  Acquisition,  and on March 31, 1998, the  Acquisition
and related  financing were completed.  The Company,  through the acquisition of
ARDIS,  becomes a  nationwide  provider  of  wireless  communications  services,
including data, dispatch, and voice services, primarily to business customers in
the United States.

On October 16, 1997,  American Mobile Radio Corporation,  an indirect subsidiary
of American  Mobile through its subsidiary  AMRC Holdings,  Inc.  (together with
American Mobile Radio Corporation,  "AMRC"), was awarded a license by the FCC to
provide  satellite-based  Digital Audio Radio Service  ("DARS")  throughout  the
United States, following its successful $89.9 million bid at auction on April 2,
1997.  AMRC has and will  continue to receive  funding for this business from an
independent  source  in  exchange  for  debt  and an  equity  interest  in AMRC.
Accordingly,  it is not expected that the development of this business will have
a material impact on the Company's financial position, results of operations, or
cash flows.

American Mobile is devoting its efforts to expanding a developing business. This
effort involves  substantial risk,  including  successfully  integrating  ARDIS.
Specifically,  future operating results will be subject to significant business,
economic,    regulatory,    technical,   and   competitive   uncertainties   and
contingencies. Depending on their extent and timing, these factors, individually
or in the  aggregate,  could have an adverse  effect on the Company's  financial
condition and future results of operations.









2.  Significant Accounting Policies
- -----------------------------------

Basis of Presentation
- ---------------------

The unaudited  consolidated  condensed financial statements included herein have
been  prepared  pursuant  to the rules and  regulations  of the  Securities  and
Exchange  Commission.  Certain  information  and footnote  disclosures  normally
included in financial  statements prepared in accordance with generally accepted
accounting principles have been condensed or omitted. While the Company believes
that the  disclosures  made are adequate to make the information not misleading,
these consolidated  financial  statements should be read in conjunction with the
consolidated  financial  statements  and related notes included in the Company's
1997 Annual Report on Form 10-K.

The  consolidated  balance  sheet as of March  31,  1998,  and the  consolidated
statements  of loss and cash flows for the three months ended March 31, 1998 and
1997,  have been  prepared  by the  Company  without  audit.  In the  opinion of
management,   all  adjustments  (consisting  of  normal  recurring  adjustments)
necessary to present  fairly the financial  position,  result of operations  and
cash flows at March 31, 1998, and for all periods  presented have been made. The
balance  sheet at December  31,  1997 has been taken from the audited  financial
statements.

Acquisition
- -----------

Subject to certain  purchase price adjustment  provisions,  the Company acquired
ARDIS  for a  purchase  price  of $50  million  in cash and $50  million  in the
Company's Common Stock and warrants (the "Purchase Price").  Approximately $11.5
million  of the  shares  that are  issuable  to  Motorola  are  contingent  upon
stockholer  approval at the May 20, 1998 annual meeting of  stockholders.  These
have been included in the purchase  price shares since holders of  approximately
76% of the Company's  Common Stock have entered into an agreement  with Motorola
to approve  the  issuance  of the  additional  shares.  The  purchase  method of
accounting  for  business  combinations  was  used  for  the  recording  of  the
Acquisition.  The  operating  results  of ARDIS  have not been  included  in the
Company's  consolidated  statements of loss,  since the Acquisition  occurred on
March 31,  1998;  however,  the balance  sheet of ARDIS as of March 31, 1998 has
been included in the  consolidated  balance sheet of the Company.  The Company's
preliminary  estimate of the excess of the purchase price over the fair value of
net  assets  acquired  is  $67.6  million.  The  Company  has  not  specifically
identified amounts to assign to certain intangibles and licenses; changes in the
amounts  allocated  to such  assets  could  result in  changes  to the amount of
goodwill recorded.  A preliminary  amortization  period of twenty years has been
selected  for the pro forma  financial  information,  which is  expected  in all
material  respects to be  representative  of the amortization  expense that will
result from the ultimate allocation to the specific intangible assets.


The  unaudited pro forma  results give effect to (i) the  Acquisition,  (ii) the
Offering  and  (iii) the New Bank  Financing  as if such  transactions  had been
consummated on January 1 of each of the periods presented.



                                                     Three Months Ended
                                                          March 31,
(dollars in thousands, except per share data)        1998          1997
                                                   --------      --------
                                                                 
Revenues                                           $19,954         $19,513
Net loss                                          $(38,849)       $(41,257)
Loss per share                                      $(1.23)         $(1.32)
Weighted-average shares outstanding                 31,503          31,371


Net Loss Per Share
- ------------------

Basic and diluted loss per common share is based on the weighted-average  number
of shares of Common  Stock  outstanding  during the  period.  Stock  options and
common stock  purchase  warrants are not  reflected  since their effect would be
antidilutive.

Recently Adopted Accounting Pronouncements
- ------------------------------------------

In June 1997, the Financial Accounting Standards Board ("FASB") issued Statement
of Financial  Accounting  Standards ("SFAS") No. 130,  "Reporting  Comprehensive
Income," and SFAS No. 131,  "Disclosures  about  Segments of an  Enterprise  and
Related  Information."  The Company  adopted SFAS No. 130 during the three month
period ended March 31, 1998.




SFAS No.  130  requires  "comprehensive  income"  and the  components  of "other
comprehensive  income" to be reported in the financial  statements  and/or notes
thereto.  Since the Company does not have any components of "other comprehensive
income," reported net income is the same as "total comprehensive income" for the
three months ended March 31, 1997 and 1998.

SFAS  No.  131  requires  an  entity  to  disclose   financial  and  descriptive
information  about  its  reportable  operating  segments.  It  also  establishes
standards for related disclosures about products and services, geographic areas,
and  major  customers.  SFAS  No.  131 is not  required  for  interim  financial
reporting  purposes  during 1998. The Company is in the process of assessing the
additional disclosures, if any, required by SFAS No. 131. However, such adoption
will not impact the Company's results of operations or financial position, since
it relates only to disclosures.

Other
- -----

The Company paid  approximately $1.5 million and $1.1 million in the three-month
periods  ended March 31,  1998 and 1997,  respectively,  to related  parties for
capital assets,  service-related  obligations,  and payments under  pre-existing
agreements.  Payments  from  related  parties  for  communication  services  and
equipment  purchases totaled $1.1 million in the three-month  period ended March
31, 1998 and $471,000  million in the  three-month  period ended March 31, 1997.
Total  indebtedness  to related parties as of March 31, 1998  approximated  $3.1
million.

3.  Liquidity and Financing
- ---------------------------

$335 Million Unit Offering
- --------------------------

In  connection  with the  Acquisition,  discussed  above,  the Company,  through
Acquisition Company, issued $335 million of Units (the "Units") consisting of 12
1/4% Senior Notes due 2008 (the  "Notes"),  and  Warrants to purchase  shares of
Common Stock of the Company.  Each Unit consists of $1,000  principal  amount of
Notes and one Warrant to purchase  3.75749 shares of Common Stock at an exercise
price of $12.51 per share.  The  Warrants  were  valued at $8.5  million and are
reflected in the balance sheet as a debt discount. A portion of the net proceeds
of the sale of the Units were used to finance  the  Acquisition.  In  connection
with the Notes,  the  Company  has  purchased  approximately  $113.0  million of
pledged securities that are intended to provide for the payment of the first six
interest  payments on the Notes. The Company incurred  approximately $15 million
in costs  associated  with  the  placement  of the  Notes  and the  Acquisition.
Interest payments are due semi-annually, in arrears, beginning October 1, 1998.

New Bank Financing
- ------------------

In connection with the Acquisition, the Company, the Acquisition Company and its
subsidiaries  restructured  the existing $200 million Bank  Financing (the "Bank
Financing") to provide for two facilities:  (i) the Revolving Credit Facility, a
$100 million unsecured  five-year reducing  revolving credit facility,  and (ii)
the Term Loan Facility, a $100 million five-year,  term loan facility with up to
three  additional  one-year  extensions  subject to the lenders'  approval.  The
Revolving Credit Facility bears an interest rate, generally,  of 50 basis points
above  LIBOR and is  unsecured,  with a  negative  pledge  on the  assets of the
Acquisition Company and its subsidiaries  ranking pari passu with the Notes. The
Revolving  Credit  Facility will be reduced $10 million each quarter,  beginning
with the quarter ending June 30, 2002, with the balance due on maturity of March
31, 2003.  Borrowings under the Revolving Credit Facility are subject to certain
conditions  beginning in the fourth quarter of 1998. In the event the Company is
unable to borrow amounts under the Revolving Credit Facility, the Company's cash
needs will  significantly  exceed its  available  resources,  which would have a
material adverse effect on the Company. The Revolving Credit Facility ranks pari
passu with the  Notes.  The Term Loan  Facility  is secured by the assets of the
Company,  principally its stockholdings in AMRC and the Acquisition Company, and
will be effectively subordinated to the Revolving Credit Facility and the Notes.
The New Bank Financing is severally guaranteed by Hughes Electronics Corporation
("Hughes"),  Singapore  Telecommunications  Ltd. ("Singapore Telecom") and Baron
Capital  Partners,  L.P. (the "Bank Facility  Guarantors").  In exchange for the
additional risks  undertaken by the Bank Facility  Guarantors in connection with
the New Bank  Financing,  the Company  agreed to  compensate  the Bank  Facility
Guarantors,  principally  in the  form  of 1  million  additional  warrants  and
repricing of 5.5 million warrants  previously issued  (together,  the "Guarantee
Warrants").  The Guarantee  Warrants  have an exercise  price of $12.51 and have
been valued at  approximately  $17.7 million.  As of April 30, 1998, the Company
had  outstanding  borrowings of $100 million of the Term Loan Facility at 6.51%,
and $5.0 million under the Revolving Credit Facility at 6.1875%.




In connection with the New Bank Financing,  the Company entered into an interest
rate swap  agreement.  The swap  agreement  reduces the impact of interest  rate
increases on the Term Loan  Facility.  The Company  paid a fee of  approximately
$17.9 million for the swap agreement. Under the swap agreement, the Company will
receive  an amount  equal to LIBOR  plus 50 basis  points,  paid on a  quarterly
basis, on a notional amount of $100 million until the termination  date of March
31,  2001.  The  Company  has  reflected  as an asset  the fee paid for the swap
agreement in the accompanying financial statements.  The Company is exposed to a
credit loss in the event of non  performance by the counter party under the swap
agreement.  The Company  does not  believe  there is a  significant  risk of non
performance  as the counter  party to the swap  agreement  is a major  financial
institution.

Motorola Vendor Financing
- -------------------------

Motorola has agreed to provide the Acquisition  Company with up to $10.0 million
of vendor financing (the "Vendor Financing Commitment"), which will be available
to finance up to 75% of the purchase price of additional  network base stations.
Loans under this  facility will bear interest at a rate equal to LIBOR plus 7.0%
and will be  guaranteed by the Company and each  subsidiary  of the  Acquisition
Company.  The terms of such  facility  will  require  that  amounts  borrowed be
secured by the  equipment  purchased  therewith.  This  commitment is subject to
customary  conditions,  including due  diligence,  and there can be no assurance
that the facility will be obtained by the Acquisition  Company on these terms or
at all. No amounts were outstanding under this facility as of April 30, 1998.

The Company  believes the proceeds  from the issuance of the Notes,  net of cash
used for the  Acquisition,  together  with  the  borrowings  under  the New Bank
Financing  and the  Vendor  Financing  Commitment,  will be  sufficient  to fund
operating losses, capital expenditures, working capital, and scheduled principal
and interest payments on debt through 1998 and beyond;  however, there can be no
assurance  that the Company's  current  projections  regarding the timing of its
ability to achieve positive  operating cash flow will be accurate,  and that the
Company will not need additional financing in the future.

AMRC
- ----

As previously  mentioned (see  "Organization and Business"),  AMRC was a winning
bidder for, and on October 16, 1997,  was awarded an FCC license to provide DARS
throughout the United States.  AMRC has and will continue to receive funding for
this  business  from an  independent  source in exchange  for debt and an equity
interest in AMRC.  Accordingly,  it is not expected that the development of this
business  will have a  material  impact  on the  Company's  financial  position,
results of operations, or cash flows. The Company's equity interest in AMRC may,
however, even on a fully diluted basis, become a material asset of the Company.

Summarized  financial  information  for AMRC as of March 31,  1998,  and for the
three months ended March 31, 1998 and 1997, and for the period from December 15,
1992 (date of inception) through March 31, 1998 is set forth below.


                                                                                December 15, 1992
                                              Three Months                           through
dollars in thousands                         Ended March 31,                         March 31,
                                             ---------------                         ---------
                                            1998         1997                           1998
                                            ----         ----                           -----
                                                                              
Gross sales                                $  --        $  --                          $  --
Operating expenses                         1,367           --                          2,477
Loss from operations                       1,367           --                          2,477
Interest expense                              39           --                            588
Net loss                                   1,406           --                          3,065





                                                                        As of                  As of
                                                                      March 31,             December 31,
                                                                        1998                   1997
                                                                        -----                  ----
                                                                                      
Current assets                                                        $    --               $    --
Noncurrent assets                                                      99,194                91,933
Current liabilities                                                     4,696                82,949
Noncurrent liabilities                                                 86,921                    --
Total stockholders' equity                                              7,577                 8,983






Deferred Trade Payables
- -----------------------

In the last quarter of 1997 and the first quarter of 1998, the Company  arranged
the financing of certain trade payables, and as of March 31, 1998, $18.1 million
of deferred trade  payables were  outstanding at rates ranging from 6.23% to 14%
and are generally payable by the end of 1998.

Purchase and Lease Agreement
- ----------------------------

As  previously  disclosed,  the Company has entered into certain  agreements  to
acquire a one-half ownership interest in TMI Communications and Company, Limited
Partnership's ("TMI") satellite, MSAT-1, at a cost of $60 million payable over a
five-year  period,  as well as entered into a five-year  lease of the  Company's
satellite,  MSAT-2, with African Continental  Telecommunications  Ltd. ("ACTEL")
that provides for  aggregate  lease  payments to the Company of $182.5  million.
Closing under the  agreements is subject to a number of  conditions,  including:
United States and Canadian regulatory approvals, a successful financing by ACTEL
of at least $120 million, and completion of certain satellite testing, inversion
and relocation  activities  with respect to AMSC-1.  It is anticipated  that the
closing under both the purchase and lease  agreements will occur  simultaneously
in the third quarter of 1998.

4. Legal and Regulatory Matters
- -------------------------------

Like other mobile  service  providers in the  telecommunications  industry,  the
Company is subject to substantial domestic, foreign and international regulation
including the need for regulatory  approvals to operate and expand the Satellite
Network and operate and modify subscriber equipment.

The  owneship  and  operation  of  American  Mobile's  (MSS)  system  and ARDIS'
ground-based  two-way  wireless  data  system  are  subject  to  the  rules  and
regulations of the FCC, which acts under authority granted by the Communications
Act and related federal laws. Among other things,  the FCC allocates portions of
the radio  frequency  spectrum to certain  services  and grants  licenses to and
regulates  individual  entities using that spectrum.  American  Mobile and ARDIS
operates pursuant to various licenses granted by the FCC.

The  successful  operation of the Satellite  Network is dependent on a number of
factors,  including the amount of L-band  spectrum made available to the Company
pursuant  to  an  international  coordination  process.  The  United  States  is
currently  engaged in an  international  process of  coordinating  the Company's
access to the  spectrum  that the FCC has  assigned  to the  Company.  While the
Company  believes that  substantial  progress has been made in the  coordination
process and expects that the United  States  government  will be  successful  in
securing the necessary spectrum,  the process is not yet complete. The inability
of the United States  government  to secure  sufficient  spectrum  could have an
adverse effect on the Company's  financial  position,  results of operations and
cash flows.

The Company has the necessary regulatory  approvals,  some of which are pursuant
to  special  temporary  authority,  to  continue  its  operations  as  currently
contemplated.  The  Company has filed  applications  with the FCC and expects to
file applications in the future with respect to the continued operations, change
in  operation  and  expansion  of the Network and  certain  types of  subscriber
equipment.  Certain of its  applications  pertaining to future service have been
opposed.  While the Company, for various reasons,  believes that it will receive
the necessary  approvals on a timely basis,  there can be no assurance  that the
requests  will be granted,  will be granted on a timely basis or will be granted
on  conditions  favorable  to  the  Company.  Any  significant  changes  to  the
applications resulting from the FCC's review process or any significant delay in
their approval could adversely affect the Company's financial position,  results
of operations and cash flows.

American Mobile is authorized to build, launch and operate three  geosynchronous
satellites in accordance  with a specified  schedule.  American Mobile is not in
compliance with the schedule for commencement and construction of its second and
third satellites and has petitioned the FCC for changes to the schedule. Certain
of these extension requests have been opposed by third parties.  The FCC has not
acted on American  Mobile's  requests.  The FCC has the  authority to revoke the
authorizations  for the second and third satellites and, in connection with such
a revocation, could exercise its authority to rescind American Mobile's license.
American  Mobile  believes  that the  exercise of such  authority to rescind the
license is unlikely. The term of the license for each of American Mobile's three
authorized  satellites is ten years,  beginning when American  Mobile  certifies
that the respective  satellite is operating in compliance with American Mobile's
license.  The ten-year term of MSAT-2 began August 21, 1995.  Although  American
Mobile  anticipates  that the  authorizations  are likely to be  extended in due
course to correspond to the useful lives of the satellites and that new licenses
will be  granted  for  replacement  satellites,  there is no  assurance  of such
extension or grant.






As a provider of interstate telecommunications services, the Company is required
to contribute to the FCC's universal  service fund, which supports the provision
of  telecommunication  services to  high-cost  areas,  and  establishes  funding
mechanisms  to support the provision of service to schools,  libraries and rural
health care providers.  The regulation became effective on January 1, 1998. This
cost  is not  born by the  Company,  but is  passed  on to its  customers  as is
universally practiced in the industry.

On June 5, 1996,  the FCC  waived  its  one-year  construction  requirement  and
granted ARDIS extensions of time to complete the buildouts of approximately  190
sites,  as required to maintain  previously  granted  licenses.  As of April 30,
1998,  ARDIS  intends but has yet to construct  94 of these sites.  The extended
construction  deadlines  vary by site  between June 27, 1998 and March 31, 1999.
Failure to complete the  buildouts in a timely  manner could result in a loss of
licenses  for such sites from the FCC.  In  addition,  at 11 of 104  uncompleted
sites  ARDIS is required to erect a new tower,  and there is no  assurance  that
local zoning  regulations  will not affect the timetable  for the  completion of
these  sites.  

In 1992, a former director of American Mobile filed an Amended Complaint against
the Company alleging  violations of the  Communications Act of 1934, as amended,
and of the Sherman Act and breach of  contract.  The suit seeks  damages for not
less than $100 million  trebled under the antitrust laws plus punitive  damages,
interest,  attorneys fees and costs. In mid-1992, the Company filed its response
denying all  allegations.  The Company's motion for summary  judgment,  filed on
March 31, 1994,  was denied on April 18, 1996. The trial in this matter has been
postponed  to a date to be  determined  in 1998.  Management  believes  that the
ultimate outcome of this matter will not be material to the Company's  financial
position, results of operations or cash flows.


5.  Other Matters
- -----------------

At March 31, 1998, the Company had remaining contractual commitments to purchase
both  mobile data  terminal  inventory  and mobile  telephone  inventory  in the
maximum amount of $6.4 million.



6.  AMSC Acquisition Company Financial Statements
- -------------------------------------------------

In connection with the Acquisition and related  financing  discussed  above, the
Company formed a new wholly-owned  subsidiary,  AMSC Acquisition  Company,  Inc.
("Acquisition  Company"). The Company transferred all of its inter-company notes
receivables  from  and its  rights,  title  and  interests  in  AMSC  Subsidiary
Corporation,  American Mobile Satellite Sales Corporation,  and AMSC Sales Corp.
Ltd. to Acquisition Company, and AMSC Acquisition Company, Inc. was the acquirer
of ARDIS and the issuer of the $335  million of Senior  Notes.  American  Mobile
Satellite  Corporation  ("Parent") has  guaranteed the Senior Notes.  The Senior
Notes  contain  covenants  that,  among  other  things,  limit  the  ability  of
Acquisition  Company to incur  additional  indebtedness,  pay  dividends or make
other distributions,  repurchase any capital stock or subordinated indebtedness,
make certain investments,  create certain liens, enter into certain transactions
with affiliates, sell assets, enter into certain mergers and consolidations, and
enter into sale and leaseback transactions.

Major  differences  between the financial  statements of Parent and  Acquisition
Company  include  (i)  as of the  Acquisition,  the  Term  Loan  Facility  is an
obligation of Parent and, as such,  the related debt and interest  costs are not
included in the Acquisition  Company  financial  statements for the period ended
and as of March 31, 1998, as discussed in Note 3, and (ii) certain  intercompany
management fees and expenses between the Parent and Acquisition Company that are
not eliminated at the Acquisition Company level.

The combined condensed financial statements of Acquisition Company are set forth
below.








                         AMSC Acquisition Company, Inc.
                      Combined Condensed Statements of Loss
                             (dollars in thousands)
                                   (Unaudited)




                                                    Three Months Ended
                                                         March 31,

                                                  1998              1997
                                                ---------         --------


REVENUES

                                                              
       Services                                   $6,418           $4,173
       Sales of equipment                          3,604            4,532
                                                  ------           ------

       Total Revenues                             10,022            8,705


COSTS AND EXPENSES:

       Cost of service and operations              7,728            8,873
       Cost of equipment sold                      3,881            5,442
       Sales and advertising                       2,993            3,221
       General and administrative                  3,659            4,777
       Depreciation and amortization              10,689           10,463
                                                  ------           ------

       Operating Loss                            (18,928)         (24,071)


INTEREST AND OTHER  INCOME                           141              945
INTEREST EXPENSE                                 (13,826)         (11,622)
                                                 --------         --------


NET LOSS                                        $(32,613)        $(34,748)
                                                =========        =========




















                         AMSC Acquisition Company, Inc.
                        Combined Condensed Balance Sheets
                             (dollars in thousands)
                                   (Unaudited)



                                                                                 March 31,    December 31,
ASSETS                                                                                1998            1997
                                                                                      ----            ----


CURRENT ASSETS:

                                                                                              
      Cash and cash equivalents                                                    $21,279          $2,106
      Inventory                                                                     38,554          40,321
      Accounts receivable-trade, net of allowance for doubtful accounts             11,477           8,140
      Restricted cash-current portion                                               41,038              --
      Prepaid in-orbit insurance                                                     2,889           4,564
      Other current assets                                                          15,324           9,608
                                                                                   -------         -------
             Total current assets                                                  130,561          64,739

PROPERTY AND EQUIPMENT - NET                                                       280,894         250,335
GOODWILL - NET                                                                      67,616              --
RESTRICTED CASH - Non-Current                                                       72,962              --
DEFERRED CHARGES AND OTHER ASSETS - NET                                             33,823          36,722
                                                                                   -------         -------

             Total assets                                                         $585,856        $351,796
                                                                                  ========        ========

LIABILITIES AND STOCKHOLDERS' EQUITY


CURRENT LIABILITIES:

      Accounts payable and accrued expenses                                        $27,990         $35,825
      Obligations under capital leases due within one year                           4,133             798
      Current portion of long-term debt                                             21,932          15,254
      Other current liabilities                                                      7,626           7,520
                                                                                  --------        --------
             Total current liabilities                                              61,681          59,397


DUE TO PARENT                                                                            --        441,836



LONG-TERM LIABILITIES:

      Obligations under Bank Financing                                                  --         198,000
      Senior Notes, net of discount                                                326,510              --
      Capital lease obligations                                                     12,005           3,147
      Other long-term debt                                                           1,126           1,364
      Net assets acquired in excess of purchase price (Note 12)                      2,550           2,725
      Other long-term liabilities                                                      610             647
                                                                                  --------        --------

             Total long-term liabilities                                           342,801         205,883

             Total liabilities                                                     404,482         707,116
                                                                                   -------         -------


STOCKHOLDERS' EQUITY:                                                              181,374       (355,320)
                                                                                   -------       ---------


             Total liabilities and stockholders' equity                           $585,856        $351,796
                                                                                  ========        ========









                         AMSC Acquisition Company, Inc.
                   Combined Condensed Statements of Cash Flows
                             (dollars in thousands)
                                   (Unaudited)





                                                                     Three Months Ended
                                                                         March 31,
                                                              --------------------------------
                                                                    1998           1997
                                                                    ----           ----

CASH FLOWS USED IN OPERATING ACTIVITIES:
                                                                                
Net loss                                                         $(32,613)      $(35,598)
Adjustments to reconcile net loss to net cash used in
operating activities:
             Amortization of debt discount                          2,524          1,754
             Depreciation and amortization                         10,689         10,463
             Changes in assets and liabilities:
                 Inventory                                          1,986         (3,483)
                 Prepaid in-orbit insurance                         1,675          1,693
                 Trade accounts receivable                          3,744         (1,480)
                 Other current assets                                (661)         1,051
                 Accounts payable and accrued expenses            (12,182)        (9,065)
                 Deferred trade payables                            6,436             --
                 Deferred items - net                                 293             --
                                                                   -------        ------

Net cash used in operating activities                             (18,109)       (34,665)


CASH FLOWS USED IN INVESTING ACTIVITIES:

Additions to property and equipment                                (1,126)        (3,574)
Acquisition of ARDIS                                              (51,382)            --
Purchase of restricted cash securities                           (113,050)            --
                                                                 ---------        ------
Net cash used in investing activities                            (165,508)        (3,574)

CASH FLOWS FROM FINANCING ACTIVITIES:

Funding from Parent                                               (12,127)         6,590
Principal payments under capital leases                              (135)          (952)
Proceeds from Bank Financing                                        2,000         35,000
Repayment of Bank Financing                                      (100,000)            --
Proceeds from bridge financing                                     10,000             --
Repayment of bridge financing                                     (10,000)            --
Proceeds from Senior Notes                                        326,510             --
Payments on long-term debt                                             --         (3,000)
Debt issuance costs                                               (13,458)            (9)
                                                                  --------        -------

Net cash provided by  financing activities                        202,790         37,629

Net increase (decrease) in cash and cash equivalents               19,173           (610)

CASH AND CASH EQUIVALENTS, beginning of period                      2,106          2,182
                                                                 --------         -------
CASH AND CASH EQUIVALENTS, end of period                          $21,279         $1,572
                                                                 ========         =======











                           PART I-FINANCIAL STATEMENTS

                 Item 2. Management's Discussion and Analysis of
              Interim Financial Condition and Results of Operations

This Quarterly Report on Form 10-Q includes "forward-looking  statements" within
the meaning of Section 27A of the  Securities Act of 1933 and Section 21E of the
Securities  Exchange Act of 1934.  Such  statements are identified by the use of
forward-looking  words or phrases  including,  but not limited  to,  "believes,"
"intended,"   "will  be   positioned,"   "expects,"   "expected,"   "estimates,"
"anticipates" and "anticipated." These  forward-looking  statements are based on
the Company's  current  expectations.  All statements  other than  statements of
historical  facts included in this Annual Report,  including those regarding the
Company's financial position,  business strategy,  projected costs and financing
needs,  and plans and  objectives  of  management  for  future  operations,  are
forward-looking statements.  Although the Company believes that the expectations
reflected in such  forward-looking  statements are  reasonable,  there can be no
assurance  that  such  expectations  will  prove to have been  correct.  Because
forward-looking statements involve risks and uncertainties, the Company's actual
results  could  differ  materially.  Important  factors  that could cause actual
results  to  differ  materially  from the  Company's  expectations  ("Cautionary
Statements")  are disclosed under  "Business" and  "Management's  Discussion and
Analysis of Financial  Condition  and Results of  Operations,"  and elsewhere in
this Annual Report,  including,  without  limitation,  in  conjunction  with the
forward-looking statements included in this Annual Report. These forward-looking
statements  represent the  Company's  judgment as of the date hereof and readers
are cautioned not to place undue reliance on these  forward-looking  statements.
All subsequent written and oral forward-looking  statements  attributable to the
Company or persons  acting on behalf of the Company are  expressly  qualified in
their entirety by the Cautionary Statements. Readers should carefully review the
risk factors  described in other  documents  the Company files from time to time
with the  Securities  and Exchange  Commission,  including  the Form 10-K Annual
Report filed on March 31, 1998,  the Form 10-K/A  Amended Annual Report filed on
April 15, 1998, the Current Report on Form 8-K filed on April 15, 1998, and Form
10-Q Quarterly  Reports to be filed by the Company  subsequent to this Form 10-Q
Quarterly Report and any Current Reports on Form 8-K and registration statements
filed by the Company.


General
- -------

The following  discussion and analysis  provides  information  which  management
believes  is  relevant  to an  assessment  and  understanding  of the  financial
condition and  consolidated  results of operations of American Mobile  Satellite
Corporation  (with its subsidiaries,  "American  Mobile" or the "Company").  The
discussion  should  be read  in  conjunction  with  the  consolidated  financial
statements and notes thereto.

American Mobile  Satellite  Corporation was  incorporated in May 1988 and, until
1996,  was a  development  stage  company,  engaged  primarily  in  the  design,
development,  construction,  deployment  and  financing  of a  mobile  satellite
communication   system.   On  December  31,  1997,  the  Company   (through  its
newly-formed subsidiary AMSC Acquisition Company, Inc. ("Acquisition Company")),
entered  into  a  Stock  Purchase  Agreement  (the  "Purchase  Agreement")  with
Motorola,  Inc.  ("Motorola"),  for the acquisition (the "Acquisition") of ARDIS
Company ("ARDIS"), a wholly-owned  subsidiary of Motorola that owns and operates
a two-way  wireless  data  communications  network.  On March 3,  1998,  the FCC
granted  consent  to  consummate  the  Acquisition.   On  March  31,  1998,  the
Acquisition  and related  financing were  completed.  See "Liquidity and Capital
Resources."  With the  acquisition  of  ARDIS,  the  Company  becomes  a leading
provider  of  nationwide  wireless  communications  services,   including  data,
dispatch  and voice  services,  primarily  to business  customers  in the United
States.  The  Company  offers a broad  range of  end-to-end  wireless  solutions
utilizing  a  seamless  network   consisting  of  the  nation's  largest,   most
fully-deployed  terrestrial  wireless  data network (the "ARDIS  Network") and a
satellite  in  geosynchronous  orbit (the  "Satellite  Network") (together,  the
"Network").

In connection with the  Acquisition,  the Company and its  subsidiaries  entered
into agreements with respect to the following  financings and refinancings:  (1)
$335  million of Units;  (2) the  restructuring  of its  existing  $200  million
Revolving  Credit Facility and Term Loan Facility  (collectively,  the "New Bank
Financings");  and (3) $10 million  commitment  with respect to Motorola  vendor
financing.  See "Management's Discussion and Analysis of Financial Condition and
Results of  Operations  - Liquidity  and Capital  Resources."  Additionally,  in
connection with the Acquisition and related financing,  the Company  transferred
all of its rights, title and interests in AMSC Subsidiary Corporation,  American
Mobile  Satellite  Sales  Corporation,  and AMSC  Sales  Corp.  Ltd.  (together,
"American Mobile Subsidiaries") to Acquisition Company.






On October 16, 1997,  American Mobile Radio Corporation,  an indirect subsidiary
of American  Mobile through its subsidiary  AMRC Holdings,  Inc.  (together with
American Mobile Radio Corporation,  "AMRC"), was awarded a license by the FCC to
provide  satellite-based  Digital Audio Radio Service  ("DARS")  throughout  the
United States, following its successful $89.9 million bid at auction on April 2,
1997. The  operations  and financing of AMRC are  maintained  separate and apart
from the  operations  and  financing  of  American  Mobile (see  "Liquidity  and
Financing").

Management  believes the period to period comparison of the Company's  financial
results  are not  necessarily  meaningful  and should  not be relied  upon as an
indication of future  operating  performance  due to the Company's  historically
high growth rate and the acquisition of ARDIS.


Overview
- --------

Each of American Mobile and ARDIS has incurred significant  operating losses and
negative cash flows in each year since it commenced operations, due primarily to
start-up  costs,  the costs of developing and building each network and the cost
of developing,  selling and providing its respective products and services.  The
Company is, and will continue to be, highly leveraged. As of March 31, 1998, the
Company had indebtedness of approximately $465.7 million.

The Company's future operating  results could be adversely  affected by a number
of uncertainties and factors, including (i) the timely completion and deployment
of  future  products  and  related  services,   including  among  other  things,
availability of mobile telephones, data terminals and other equipment to be used
with the Network  ("Subscriber  Equipment") being  manufactured by third parties
over which the Company has limited control,  (ii) the market's acceptance of the
Company's  services,  (iii) the  ability  and the  commitment  of the  Company's
distribution channels to market and distribute the Company's services,  (iv) the
Company's  ability to modify  its  organization,  strategy  and  product  mix to
maximize the market  opportunities in light of changes therein,  (v) competition
from existing  companies that provide  services  using  existing  communications
technologies  and the  possibility  of  competition  from  companies  using  new
technology  in  the  future,   (vi)  capacity   constraints   arising  from  the
reconfiguration of MSAT-2,  subsequent anomalies affecting MSAT-2 and MSAT-1, or
the power management  recommendation affecting both MSAT-2 and MSAT-1 previously
reported,  (vii)  additional  technical  anomalies  that may  occur  within  the
Satellite   Network, including those relating to MSAT-1 and MSAT-2,  which could
impact, among other things, the operation of the Satellite Network and the cost,
scope  or  availability  of  in-orbit  insurance,  (viii)  subscriber  equipment
inventory  responsibilities and liabilities assumed by the Company including the
ability of the Company to realize the value of its inventory in a timely manner,
(ix) the Company's ability to secure  additional  financing as may be necessary,
(x) the  Company's  ability to respond and react to changes in its  business and
the  industry  as a result of being  highly  leveraged,  (xi) the ability of the
Company  to  successfully  integrate  ARDIS  and  to  achieve  certain  business
synergies, and (xii) the ability of the Company to manage growth effectively.

As of March 31, 1998, there were approximately 85,200 units on the Network.


Quarter Ended March 31, 1998 and 1997
- -------------------------------------

Service  revenues,  which  include both the Company's  voice and data  services,
approximated  $6.4  million for the quarter  ended March 31, 1998 as compared to
$4.2 million for the same period in 1997 and represents a 52% increase year over
year.  Service revenue from voice services increased 78% from approximately $1.8
million  in the first  quarter  of 1997 to  approximately  $3.2  million  in the
comparable  period of 1998. The $1.4 million  increase was primarily a result of
an 85% increase in voice customers  during the first quarter of 1998 as compared
to the  comparable  period in 1997.  Service  revenue  from the  Company's  data
services  approximated $2.3 million in the first quarter of 1998, as compared to
$1.6 million for the comparable quarter of 1997, an increase of $700,000 or 44%.
The  increase was  primarily a result of a 25%  increase in data units.  Service
revenue  from  capacity  resellers,  who handle  both  voice and data  services,
approximated  $805,000 in the first quarter of 1998, as compared to $518,000 for
the first  quarter of 1997, an increase of $287,000 or 55%. As of March 31, 1998
and 1997,  receivables  relating to service  revenues were $4.0 million and $3.0
million, respectively.

Revenue from the sale of mobile data terminals and mobile  telephones  decreased
20% from $4.5 million in the first  quarter of 1997 to $3.6 million in the first
quarter of 1998.  The decrease was  primarily  attributable  to reduced sales of







voice products, as well as certain price reductions made in the first quarter of
1998. As of March 31, 1998 and 1997,  receivables  relating to equipment revenue
were $2.5 million and $7.0 million respectively.

Cost of service and  operations  for the first quarter of 1998,  which  includes
costs to support  subscribers  and to operate the Satellite  Network,  were $7.7
million for 1998 and $8.9  million for the same period of 1997.  Cost of service
and  operations  for the first  quarter  of 1998 and 1997,  as a  percentage  of
revenues, were 77% and 102%,  respectively.  The decrease in cost of service and
operations was primarily  attributable to a reduction in information  technology
costs affected by dramatically  reducing the dependence on outside  consultants,
offset by increased  interconnect  charges  associated  with  increased  service
usage.

The cost of equipment  sold decreased 28% from $5.4 million in the first quarter
of 1997 to $3.9 million for the same period in 1998. The dollar  decrease in the
cost of equipment sold is primarily attributable to (i) a corresponding decrease
in voice  equipment  sales  and  (ii)  the  impact  of the  inventory  valuation
allowance recorded in the fourth quarter of 1997.

Sales and  advertising  expenses were $3.0 million in the first quarter of 1998,
compared  to $3.2  million for the same  period in 1997.  Sales and  advertising
expenses as a percentage  of revenue  were 30% in the first  quarter of 1998 and
37% in the first quarter of 1997. The decrease of sales and advertising expenses
was primarily attributable to a reduction in subscriber acquisition costs as the
first quarter marketing and promotional initiatives were put on hold pending the
Acquisition.  It is  anticipated  that these costs will  increase as the Company
rolls out new marketing programs associated with the new corporate strategy.

General  and  administrative  expenses  for the first  quarter of 1998 were $3.6
million,  compared to $4.9 million in the first quarter of 1997. As a percentage
of revenue,  general and  administrative  expenses  represented 36% in the first
quarter of 1998 and 56% in the first  quarter of 1997.  The  decrease in general
and administrative expenses for 1998 compared to 1997 was primarily attributable
to (i) a $775,000 reduction in personnel expenses as a result of deferred hiring
decisions and (ii) a $371,000 reduction in insurance premiums, primarily related
to the negotiation of better rates on certain key insurance policies.

Depreciation and amortization expense was $10.2 million and $9.9 million for the
first quarter of 1998 and 1997,  respectively,  representing  approximately 101%
and 114% of revenue for the first quarter of 1998 and 1997, respectively.
 The increase in  depreciation  and  amortization  expense was  attributable  to
depreciation on newly-acquired assets.

Interest and other income was $141,000 for the first quarter of 1998 compared to
$945,000 for the same period in 1997.  The decrease was a result of other income
in the amount of $875,000  representing  proceeds  from the licensing of certain
technology  associated with the Satellite  Network received in the first quarter
of 1997,  offset by a $100,000  increase  in interest  income  earned on certain
escrowed  monies.  The Company  incurred $6.6 million of interest expense in the
first  quarter of 1998  compared  to $4.4  million  for the same period in 1997,
reflecting (i) the  amortization of debt discount and debt offering costs in the
amount of $2.5  million in 1998,  compared  to $1.8  million  in 1997,  and (ii)
higher outstanding loan balances as compared to 1997.

Interest  expense in the first  quarter of 1998 was  significant  as a result of
borrowings  under the Bank Financing,  as well as the  amortization of borrowing
costs incurred in conjunction with securing the facility. It is anticipated that
interest  costs  will  continue  to be  significant  as a  result  of  the  Bank
Financing,  Bridge  Financing,  and  Acquisition,  (see  "Liquidity  and Capital
Resources").

Net capital expenditures,  including additions financed through vendor financing
arrangements,  for the first quarter of 1998 for property and  equipment  were $
1.1 million  compared to $1.8 million for the same period in 1997.  The decrease
was largely attributable to the reduction in the acquisition of assets necessary
to complete the satellite network.


Liquidity and Capital Resources
- -------------------------------

$335 Million Unit Offering
- --------------------------

In  connection  with the  Acquisition,  discussed  above,  the Company,  through
Acquisition Company, issued $335 million of Units (the "Units") consisting of 12
1/4% Senior Notes due 2008 (the  "Notes"),  and  Warrants to purchase  shares of






Common Stock of the Company.  Each Unit consists of $1,000  principal  amount of
Notes and one Warrant to purchase  3.75749 shares of Common Stock at an exercise
price of $12.51 per share.  The  Warrants  were  valued at $8.5  million and are
reflected in the balance sheet as a debt discount. A portion of the net proceeds
of the sale of the Units were used to finance  the  Acquisition.  In  connection
with the Notes,  the  Company  has  purchased  approximately  $113.0  million of
pledged securities that are intended to provide for the payment of the first six
interest  payments on the Notes. The Company incurred  approximately $15 million
in costs  associated  with  the  placement  of the  Notes  and the  Acquisition.
Interest payments are due semi-annually, in arrears, beginning October 1, 1998.

New Bank Financing
- ------------------

In connection with the Acquisition, the Company, the Acquisition Company and its
subsidiaries  restructured  the existing $200 million Bank  Financing (the "Bank
Financing") to provide for two facilities:  (i) the Revolving Credit Facility, a
$100 million unsecured  five-year reducing  revolving credit facility,  and (ii)
the Term Loan Facility, a $100 million five-year,  term loan facility with up to
three  additional  one-year  extensions  subject to the lenders'  approval.  The
Revolving Credit Facility bears an interest rate, generally,  of 50 basis points
above  LIBOR and is  unsecured,  with a  negative  pledge  on the  assets of the
Acquisition Company and its subsidiaries  ranking pari passu with the Notes. The
Revolving  Credit  Facility will be reduced $10 million each quarter,  beginning
with the quarter ending June 30, 2002, with the balance due on maturity of March
31, 2003.  Borrowings under the Revolving Credit Facility are subject to certain
conditions  beginning in the fourth quarter of 1998. In the event the Company is
unable to borrow amounts under the Revolving Credit Facility, the Company's cash
needs will  significantly  exceed its  available  resources,  which would have a
material adverse effect on the Company. The Revolving Credit Facility ranks pari
passu with the  Notes.  The Term Loan  Facility  is secured by the assets of the
Company,  principally its stockholdings in AMRC and the Acquisition Company, and
will be effectively subordinated to the Revolving Credit Facility and the Notes.
The New Bank Financing is severally guaranteed by Hughes Electronics Corporation
("Hughes"),  Singapore  Telecommunications  Ltd. ("Singapore Telecom") and Baron
Capital  Partners,  L.P. (the "Bank Facility  Guarantors").  In exchange for the
additional risks  undertaken by the Bank Facility  Guarantors in connection with
the New Bank  Financing,  the Company  agreed to  compensate  the Bank  Facility
Guarantors,  principally  in the  form  of 1  million  additional  warrants  and
repricing of 5.5 million warrants  previously issued  (together,  the "Guarantor
Warrants").  The Guarantee  Warrants  have an exercise  price of $12.51 and have
been valued at  approximately  $17.7 million.  As of April 30, 1998, the Company
had  outstanding  borrowings of $100 million of the Term Loan Facility at 6.51%,
and $5.0 million under the Revolving Credit Facility at 6.1875%.

In connection with the New Bank Financing,  the Company entered into an interest
rate swap  agreement.  The swap  agreement  reduces the impact of interest  rate
increases on the Term Loan  Facility.  The Company  paid a fee of  approximately
$17.9 million for the swap agreement. Under the swap agreement, the Company will
receive  an amount  equal to LIBOR  plus 50 basis  points,  paid on a  quarterly
basis, on a notional amount of $100 million until the termination  date of March
31,  2001.  The  Company  has  reflected  as an asset  the fee paid for the swap
agreement in the accompanying financial statements.  The Company is exposed to a
credit loss in the event of non  performance by the counter party under the swap
agreement.  The Company  does not  believe  there is a  significant  risk of non
performance  as the counter  party to the swap  agreement  is a major  financial
institution.

Motorola Vendor Financing
- -------------------------

Motorola has agreed to provide the Acquisition  Company with up to $10.0 million
of vendor financing (the "Vendor Financing Commitment"), which will be available
to finance up to 75% of the purchase price of additional  network base stations.
Loans under this  facility will bear interest at a rate equal to LIBOR plus 7.0%
and will be  guaranteed by the Company and each  subsidiary  of the  Acquisition
Company.  The terms of such  facility  will  require  that  amounts  borrowed be
secured by the  equipment  purchased  therewith.  This  commitment is subject to
customary  conditions,  including due  diligence,  and there can be no assurance
that the facility will be obtained by the Acquisition  Company on these terms or
at all. No amounts were outstanding under this facility as of April 30, 1998.

The Company  believes the proceeds  from the issuance of the Notes,  net of cash
used for the  Acquisition,  together  with  the  borrowings  under  the New Bank
Financing  and the  Vendor  Financing  Commitment,  will be  sufficient  to fund
operating losses, capital expenditures, working capital, and scheduled principal
and interest payments on debt through 1998 and beyond;  however, there can be no
assurance  that the Company's  current  projections  regarding the timing of its
ability to achieve positive  operating cash flow will be accurate,  and that the
Company will not need additional financing in the future.




AMRC
- ----

As previously  mentioned (see  "Organization and Business"),  AMRC was a winning
bidder for, and on October 16, 1997,  was awarded an FCC license to provide DARS
throughout the United States.  AMRC has and will continue to receive funding for
this  business  from an  independent  source in exchange  for debt and an equity
interest in AMRC.  Accordingly,  it is not expected that the development of this
business  will have a  material  impact  on the  Company's  financial  position,
results of operations, or cash flows. The Company's equity interest in AMRC may,
however, even on a fully diluted basis, become a material asset of the Company.

Deferred Trade Payables
- -----------------------

In the last quarter of 1997 and the first quarter of 1998, the Company  arranged
the financing of certain trade payables, and as of March 31, 1998, $18.1 million
of deferred trade  payables were  outstanding at rates ranging from 6.23% to 14%
and are generally payable by the end of 1998.

Purchase and Lease of Satellite
- -------------------------------

As  previously  disclosed,  the Company has entered into certain  agreements  to
acquire a one-half ownership interest in TMI Communications and Company, Limited
Partnership's ("TMI") satellite, MSAT-1, at a cost of $60 million payable over a
five-year  period,  as well as entered  into  five-year  lease of the  Company's
satellite,  MSAT-2,  with  African  Continental   Telecommunications  Ltd.  that
provides for aggregate lease payments to the Company of $182.5 million.  Closing
under the  agreements is subject to a number of  conditions,  including:  United
States and Canadian regulatory approvals,  a successful financing by ACTEL of at
least $120 million,  and completion of certain satellite testing,  inversion and
relocation activities with respect to AMSC-1. It is anticipated that the closing
under  both the  purchase  and lease  agreements  will occur  simultaneously  in
the third quarter of 1998.

Other
- -----

At March 31, 1998, the Company had remaining contractual commitments to purchase
both mobile data terminal inventory and mobile telephone inventory approximating
$6.4 million.

Cash  used in  operating  activities  for the  first  quarter  of 1998 was $10.9
million as compared to $26.7 million for the first quarter of 1997. The decrease
in cash used in operating activities was primarily attributable to (i) decreased
operating losses, and (ii) decreased inventory and accounts receivable balances.
Cash used by investing  activities  was $193.4  million for the first quarter of
1998 compared to $6.6 million during the first quarter of 1997. The increase was
primarily  attributable  to the  acquisition of ARDIS and the funding of certain
escrows required in connection with the Acquisition.  Cash provided by financing
activities  was $223.5  million  during the first quarter of 1998 as compared to
$32.7 million during the first quarter of 1997, reflecting (i) the proceeds from
the Notes Bank,  offset by (ii) the repayment of a portion of the Bank Financing
and (iii)  payment of financing  fees  associated  with the  acquisition  of the
Notes.  As of March 31,  1998,  the Company  had $21.3  million of cash and cash
equivalents and working capital of $71.4 million.

Other Matters
- -------------

In June 1997, the Financial Accounting Standards Board ("FASB") issued Statement
of Financial  Accounting  Standards ("SFAS") No. 130,  "Reporting  Comprehensive
Income," and SFAS No. 131,  "Disclosures  about  Segments of an  Enterprise  and
Related  Information."  The Company  adopted SFAS No. 130  standards  during the
three month period ended March 31, 1998.

SFAS No.  130  requires  "comprehensive  income"  and the  components  of "other
comprehensive  income" to be reported in the financial  statements  and/or notes
thereto.  Since the Company does not have any components of "other comprehensive
income," reported net income is the same as "total comprehensive income" for the
three months ended March 31, 1997 and 1998.

SFAS  No.  131  requires  an  entity  to  disclose   financial  and  descriptive
information  about  its  reportable  operating  segments.  It  also  establishes
standards for related disclosures about products and services, geographic areas,
and  major  customers.  SFAS  No.  131 is not  required  for  interim  financial
reporting  purposes  during 1998. The Company is in the process of assessing the
additional disclosures, if any, required by SFAS No. 131. However, such adoption
will not impact the Company's results of operations or financial position, since
it relates only to disclosures.








                          PART II -- OTHER INFORMATION

                    Item 6. Exhibits and Reports on Form 8-K

               (a) Exhibits

3.1       -    Restated  Certificate  of  Incorporation  of  AMSC  (as  restated
               effective May 1, 1996)  (Incorporated by reference to Exhibit 3.1
               to the  Company's  Quarterly  Report on Form 10-Q for the periods
               ending March 31,1996 and June 30, 1996 (File No. 0-23044))

3.2       -    Amended and  Restated  Bylaws of AMSC (as  amended  and  restated
               effective  February  29,  1996)  (Incorporated  by  reference  to
               Exhibit 3.2 to the  Company's  Annual Report on Form 10-K for the
               fiscal year ending December 31, 1995 (File No. 0-23044))

4.1       -    Indenture of AMSC Acquisition Company,  Inc., Series A and Series
               B,  12  1/4%  Senior  Notes  Due  2008,   dated  March  31,  1998
               (Incorporated by reference to Registration  Statement on Form S-4
               filed on even date herewith.)

4.2       -    Debt  Registration  Rights  Agreement dated March 31, 1998 by and
               among AMSC Acquisition  Company,  Inc., Bear, Stearns & Co. Inc.,
               J.P.  Morgan  Securities  Inc.,  TD  Securities  (USA)  Inc.  and
               BancAmerica  Robertson  Stephens,  and  guarantors  party thereto
               (Incorporated by reference to Registration  Statement on Form S-4
               filed on even date herewith.)

4.3       -    Unit Agreement Among American  Mobile Satellite Corporation, AMSC
               Acquisition Company, Inc. and State Street Bank and Trust Company
               as Unit Agent, dated March 31, 1998 (Incorporated by reference to
               Registration Statement on Form S-4 filed on even date herewith.)

4.4       -    Warrant Agreement  between American Mobile Satellite  Corporation
               as Issuer  and State  Street  Bank and Trust  Company  as Warrant
               Agent  dated  March  31,  1998   (Incorporated  by  reference  to
               Registration Statement on Form S-4 filed on even date herewith.)

4.5       -    Warrant Registration Rights Agreement dated March 31, 1998 By and
               Among American Mobile Satellite  Corporation and Bear,  Stearns &
               Co. Inc., J.P. Morgan  Securities  Inc.,  T.D.  Securities  (USA)
               Inc.,  BancAmerica Robertson Stephens  (Incorporated by reference
               to  Registration  Statement  on  Form  S-4  filed  on  even  date
               herewith.)

4.6       -    Pledge  and  Security  Agreement  by and among  AMSC  Acquisition
               Company,  Inc.,  State Street Bank and Trust Company,  as Trustee
               and State  Street Bank and Trust  Company,  as  Collateral  Agent
               dated March 31, 1998  (Incorporated  by reference to Registration
               Statement on Form S-4 filed on even date herewith.)

10.65     -    Stock  Purchase  Agreement for the  Acquisition of Motorola ARDIS
               Acquisition,  Inc. and Motorola ARDIS,  Inc. by AMSC  Acquisition
               Company,  Inc., a Wholly-  Owned  Subsidiary  of American  Mobile
               Satellite   Corporation,   Dated   as  of   December   31,   1997
               (Incorporated by reference to Exhibit 10.65 previously filed with
               the Report on Form 10-K for the period  ending  December 31, 1997
               (File No. 0-23044)).

10.65(a)  -    Amendment  No.  1dated  March  31,  1998  to the  Stock  Purchase
               Agreement for the Acquisition of Motorola ARDIS Acquisition, Inc.
               and Motorola ARDIS,  Inc. by AMSC  Acquisition  Company,  Inc., a
               Wholly-Owned  Subsidiary of American Mobile Satellite Corporation
               (Incorporated  by  reference  to Exhibit 4.2 to the  Schedule 13D
               dated March 31, 1998, filed by Motorola, Inc.)




10.66     -    Participation  Rights  Agreement  by and  among  Motorola,  Inc.,
               American Mobile Satellite Corporation,  and the parties listed on
               Schedule  A,  dated as of  December  31,  1997  (Incorporated  by
               reference to Exhibit  10.66  previously  filed with the Report on
               Form 10-K for the  period  ending  December  31,  1997  (File No.
               0-23044)).

10.67     -    Registration  Rights  Agreement  by  and  among  Motorola,  Inc.,
               American Mobile Satellite  Corporation dated as of March 31, 1998
               (Incorporated  by  reference  to Exhibit 4.4 to the  Schedule 13D
               dated March 31, 1998, filed by Motorola, Inc.)

10.68     -    Guaranty  Issuance  Agreement,  dated as of March 31, 1998, among
               Hughes  Electronics  Corporation,   Singapore  Telecommunications
               Ltd.,  and Baron  Capital  Partners,  L.P.  and  American  Mobile
               Satellite   Corporation  and  AMSC  Acquisition   Company,   Inc.
               (Incorporated by reference to Exhibit 1 to the Schedule 13D dated
               March  31,  1998,  filed  by  Hughes   Communications   Satellite
               Services, Inc. )

10.69     -    Warrant for the  Purchase  of Shares of Common  Stock of American
               Mobile  Satellite  Corporation,   dated  as  of  March  31,  1998
               (Incorporated by reference to Exhibit 2 to the Schedule 13D dated
               March  31,  1998,  filed  by  Hughes   Communications   Satellite
               Services, Inc. )

10.70     -    Amended and Restated  Registration Rights Agreement,  dated as of
               March 31, 1998, among American Mobile  Satellite  Corporation and
               Hughes  Electronics  Corporation,   Singapore  Telecommunications
               Ltd., and Baron Capital Partners, L.P. (Incorporated by reference
               to Exhibit 3 to the Schedule  13D dated March 31, 1998,  filed by
               Hughes Communications Satellite Services, Inc.)

10.71     -    Amendment No. 2 to the Warrant Certificate, dated as of March 31,
               1998, by and among  American  Mobile  Satellite  Corporation  and
               Hughes  Electronics  Corporation,   Singapore  Telecommunications
               Ltd., and Baron Capital Partners, L.P. (Incorporated by reference
               to Exhibit 4 to the Schedule  13D dated March 31, 1998,  filed by
               Hughes Communications Satellite Services, Inc. )

10.72     -    Term Credit  Agreement  dated as of March 31, 1998 among American
               Mobile  Satellite  Corporation,  Morgan Guaranty Trust Company of
               New York,  Toronto Dominion  (Texas),  Inc. and other banks party
               thereto (filed herewith.)

10.73     -    Revolving  Credit Agreement dated as of March 31, 1998 among AMSC
               Acquisition Company, Inc., American Mobile Satellite Corporation,
               Morgan  Guaranty  Trust Company of New York and Toronto  Dominion
               (Texas), Inc. and other banks party thereto (filed herewith.)

11.1      -    Computations of Earning Per Common Share (filed herewith)

27.0      -    Financial Data Schedule (filed herewith)


               (b) Reports on Form 8-K:

         On April 15,  1998,  the  Company  filed a Current  Report on Form 8-K,
         describing in response to Item  2-Acquisition or Disposition of Assets,
         the acquisition of ARDIS Company from Motorola, Inc.








                                    SIGNATURE

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.

                                    AMERICAN MOBILE SATELLITE CORPORATION
                                    (Registrant)


Date: May 14, 1998                  By:/s/STEPHEN D. PECK
                                    --------------------------------------------
                                    Stephen D. Peck
                                    Vice President and Chief Financial Officer
                                    (principal financial and accounting officer)







                                  EXHIBIT INDEX



Number            Description

3.1       -    Restated  Certificate  of  Incorporation  of  AMSC  (as  restated
               effective May 1, 1996)  (Incorporated by reference to Exhibit 3.1
               to the  Company's  Quarterly  Report on Form 10-Q for the periods
               ending March 31,1996 and June 30, 1996 (File No. 0-23044))

3.2       -    Amended and  Restated  Bylaws of AMSC (as  amended  and  restated
               effective  February  29,  1996)  (Incorporated  by  reference  to
               Exhibit 3.2 to the  Company's  Annual Report on Form 10-K for the
               fiscal year ending December 31, 1995 (File No. 0-23044))

4.1       -    Indenture of AMSC Acquisition Company,  Inc., Series A and Series
               B,  12  1/4%  Senior  Notes  Due  2008,   dated  March  31,  1998
               (Incorporated by reference to Registration  Statement on Form S-4
               filed on even date herewith.)

4.2       -    Debt  Registration  Rights  Agreement dated March 31, 1998 by and
               among AMSC Acquisition  Company,  Inc., Bear, Stearns & Co. Inc.,
               J.P.  Morgan  Securities  Inc.,  TD  Securities  (USA)  Inc.  and
               BancAmerica  Robertson  Stephens,  and  guarantors  party thereto
               (Incorporated by reference to Registration  Statement on Form S-4
               filed on even date herewith.)

4.3       -    Unit Agreement Among American  Mobile Satellite Corporation, AMSC
               Acquisition Company, Inc. and State Street Bank and Trust Company
               as Unit Agent, dated March 31, 1998 (Incorporated by reference to
               Registration Statement on Form S-4 filed on even date herewith.)

4.4       -    Warrant Agreement  between American Mobile Satellite  Corporation
               as Issuer  and State  Street  Bank and Trust  Company  as Warrant
               Agent  dated  March  31,  1998   (Incorporated  by  reference  to
               Registration Statement on Form S-4 filed on even date herewith.)

4.5       -    Warrant Registration Rights Agreement dated March 31, 1998 By and
               Among American Mobile Satellite  Corporation and Bear,  Stearns &
               Co. Inc., J.P. Morgan  Securities  Inc.,  T.D.  Securities  (USA)
               Inc.,  BancAmerica Robertson Stephens  (Incorporated by reference
               to  Registration  Statement  on  Form  S-4  filed  on  even  date
               herewith.)

4.6       -    Pledge  and  Security  Agreement  by and among  AMSC  Acquisition
               Company,  Inc.,  State Street Bank and Trust Company,  as Trustee
               and State  Street Bank and Trust  Company,  as  Collateral  Agent
               dated March 31, 1998  (Incorporated  by reference to Registration
               Statement on Form S-4 filed on even date herewith.)

10.65     -    Stock  Purchase  Agreement for the  Acquisition of Motorola ARDIS
               Acquisition,  Inc. and Motorola ARDIS,  Inc. by AMSC  Acquisition
               Company,  Inc., a Wholly-  Owned  Subsidiary  of American  Mobile
               Satellite   Corporation,   Dated   as  of   December   31,   1997
               (Incorporated by reference to Exhibit 10.65 previously filed with
               the Report on Form 10-K for the period  ending  December 31, 1997
               (File No. 0-23044)).

10.65(a)  -    Amendment  No.  1dated  March  31,  1998  to the  Stock  Purchase
               Agreement for the Acquisition of Motorola ARDIS Acquisition, Inc.
               and Motorola ARDIS,  Inc. by AMSC  Acquisition  Company,  Inc., a
               Wholly-Owned  Subsidiary of American Mobile Satellite Corporation
               (Incorporated  by  reference  to Exhibit 4.2 to the  Schedule 13D
               dated March 31, 1998, filed by Motorola, Inc.)




10.66     -    Participation  Rights  Agreement  by and  among  Motorola,  Inc.,
               American Mobile Satellite Corporation,  and the parties listed on
               Schedule  A,  dated as of  December  31,  1997  (Incorporated  by
               reference to Exhibit  10.66  previously  filed with the Report on
               Form 10-K for the  period  ending  December  31,  1997  (File No.
               0-23044)).

10.67     -    Registration  Rights  Agreement  by  and  among  Motorola,  Inc.,
               American Mobile Satellite  Corporation dated as of March 31, 1998
               (Incorporated  by  reference  to Exhibit 4.4 to the  Schedule 13D
               dated March 31, 1998, filed by Motorola, Inc.)

10.68     -    Guaranty  Issuance  Agreement,  dated as of March 31, 1998, among
               Hughes  Electronics  Corporation,   Singapore  Telecommunications
               Ltd.,  and Baron  Capital  Partners,  L.P.  and  American  Mobile
               Satellite   Corporation  and  AMSC  Acquisition   Company,   Inc.
               (Incorporated by reference to Exhibit 1 to the Schedule 13D dated
               March  31,  1998,  filed  by  Hughes   Communications   Satellite
               Services, Inc. )

10.69     -    Warrant for the  Purchase  of Shares of Common  Stock of American
               Mobile  Satellite  Corporation,   dated  as  of  March  31,  1998
               (Incorporated by reference to Exhibit 2 to the Schedule 13D dated
               March  31,  1998,  filed  by  Hughes   Communications   Satellite
               Services, Inc. )

10.70     -    Amended and Restated  Registration Rights Agreement,  dated as of
               March 31, 1998, among American Mobile  Satellite  Corporation and
               Hughes  Electronics  Corporation,   Singapore  Telecommunications
               Ltd., and Baron Capital Partners, L.P. (Incorporated by reference
               to Exhibit 3 to the Schedule  13D dated March 31, 1998,  filed by
               Hughes Communications Satellite Services, Inc.)

10.71     -    Amendment No. 2 to the Warrant Certificate, dated as of March 31,
               1998, by and among  American  Mobile  Satellite  Corporation  and
               Hughes  Electronics  Corporation,   Singapore  Telecommunications
               Ltd., and Baron Capital Partners, L.P. (Incorporated by reference
               to Exhibit 4 to the Schedule  13D dated March 31, 1998,  filed by
               Hughes Communications Satellite Services, Inc. )

10.72     -    Term Credit  Agreement  dated as of March 31, 1998 among American
               Mobile  Satellite  Corporation,  Morgan Guaranty Trust Company of
               New York,  Toronto Dominion  (Texas),  Inc. and other banks party
               thereto (filed herewith.)

10.73     -    Revolving  Credit Agreement dated as of March 31, 1998 among AMSC
               Acquisition Company, Inc., American Mobile Satellite Corporation,
               Morgan  Guaranty  Trust Company of New York and Toronto  Dominion
               (Texas), Inc. and other banks party thereto (filed herewith.)

11.1      -    Computations of Earning Per Common Share (filed herewith)

27.0      -    Financial Data Schedule (filed herewith)