EXHIBIT 10.7



                      AMERICAN MOBILE SATELLITE CORPORATION
                      -------------------------------------
                          EMPLOYEE STOCK PURCHASE PLAN
                          ----------------------------


                                    ARTICLE I
                                    ---------
                          PURPOSE AND SCOPE OF THE PLAN
                          -----------------------------


1.1        Purpose

           The American  Mobile  Satellite  Corporation  Employee Stock Purchase
Plan is  intended to  encourage  employee  participation  in the  ownership  and
economic progress of the Corporation.


1.2        Definitions

           Unless the context clearly indicates  otherwise,  the following terms
have the meaning set forth below:

           "AMSC  Benefits  Administration"  shall  mean the Corporation's Human
Resources Group.

           "Board" shall mean the Board of Directors of the Corporation.

           "Code" shall mean the Internal Revenue Code of 1986, as amended.

           "Committee"  shall mean a committee  of officers or  employees of the
Corporation and/or one or more of its Subsidiaries appointed by the Board, which
Committee shall administer the Plan as provided in Section 1.3 hereof.

           "Common Stock" shall mean shares of common stock of the Corporation.

           "Compensation"  shall mean the base salary,  bonuses,  overtime,  and
commissions paid to an Employee by the Corporation or a Subsidiary in accordance
with established payroll procedures.

           "Corporation" shall mean American Mobile Satellite Corporation.

           "Covered  Officer"  shall  mean an  Employee  who is  subject  to the
reporting requirements of Section 16(a) of the Exchange Act.

           "Eligible  Employee"  shall mean an Employee  who (i) is scheduled to
work at least 20 hours per week and (ii) whose customary employment is more than
five (5) months in a calendar year.

           "Employee"   shall   mean  any  employee  of  the  Corporation  or  a
Subsidiary.

           "Exchange Act"  shall  mean  the  Securities Exchange Act of 1934, as
amended.

           "Exercise  Date" shall mean June 30 and December 31 of each Plan Year
beginning after 1993.

           "Fair  Market  Value" of a share of Common  Stock shall mean (i) with
respect to the Initial Offering Date, the price at which a share of Common Stock
is sold to the  public  in the  Initial  Public  Offering,  or (ii) in all other
cases,  the amount  equal to the average of the closing bid and asked for prices
of a Share on the applicable  date as reported by the  consolidated  tape of the
National Association of Securities Dealers Automated Quotation (or on such other
recognized  quotation system on which the trading prices of the Common Stock are
quoted on the applicable  date),  or, if no Share  transactions  are reported on
such tape (or such other  system) on the  applicable  date,  the  average of the


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closing bid and asked for prices of a Share on the immediately preceding date on
which  Share  transactions  were so  reported,  or as  determined  pursuant to a
reasonable method adopted by the Committee in good faith for such purpose.

           "Initial Offering" shall mean the first Option Period under the Plan,
which shall begin on the Initial Offering Date and shall end on June 30, 1994.

           "Initial Offering Date" shall mean December 13, 1993.

           "Offering  Date"  shall  mean July 1 and  January 1 of each Plan Year
beginning  after 1993,  provided  that  January 1, 1994 shall not be an Offering
Date.

           "Option  Period" shall mean (i) in the case of the Initial  Offering,
the period  beginning on the Initial  Offering Date and ending on June 30, 1994,
or (ii) in all other cases,  the period beginning on an Offering Date and ending
on the next succeeding Exercise Date.

           "Option Price" shall mean the  purchase price  of  a  share of Common
Stock hereunder as provided in Section 3.1
hereof.

           "Participant"  shall   mean  any  Eligible  Employee  who  elects  to
participate.

           "Plan" shall mean this American Mobile Satellite Corporation Employee
Stock Purchase Plan, as the same may be amended from time to time.

           "Plan  Account" shall mean an account  established  and maintained by
the Corporation in the name of each Participant.

           "Plan Year" shall mean the twelve (12) month period beginning January
1 and ending on the following December 31.

           "Stock  Purchase  Agreement"  shall mean the form  prescribed  by the
Committee which must be executed by an Employee who elects to participate in the
Plan.

           "Subsidiary"  shall mean any company in which the  Corporation  owns,
directly or indirectly, shares possessing 50% of the total combined voting power
of all classes of stock.


1.3        Administration of Plan

           The Committee  shall have the authority to administer the Plan and to
make and adopt rules and regulations not inconsistent with the provisions of the
Plan, provided that, except with respect to the Initial Offering,  the Committee
also is authorized to change the Offering  Periods,  Offering Dates and Exercise
Dates under the Plan by providing  written  notice to all  Employees at least 15
days prior to the Exercise Date  following  which such changes will take effect.
The Committee  shall adopt the form of Stock Purchase  Agreement and all notices
required hereunder.  The Committee may delegate  administrative  tasks under the
Plan to one or more agents.  The  Committee's  interpretation  and  decisions in
respect to the Plan shall be final and conclusive.


1.4        Effective Date of Plan

           The plan shall become  effective on December 13, 1993, which shall be
the  Initial  Offering  Date,   provided  that  the  Plan  is  approved  by  the
stockholders  of the  Corporation  within 12 months before or after the date the
Plan is adopted by the Board.


1.5        Termination of Plan

           The Plan shall  continue in effect  through  December 31, 2003 unless
terminated prior thereto  pursuant to Section 4.3 hereof,  or by the Board which
shall  have  the  right  to  terminate  the  Plan at any  time.  Upon  any  such
termination,  the balance of any payroll  deductions in each  Participant's Plan
Account shall be refunded and,  except as provided in Article VI with respect to
Covered  Officers,  a certificate or certificates for any shares of Common Stock
in each Participant's Plan Account shall be distributed to the Participant.

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                                   ARTICLE II
                                   ----------
                                 PARTICIPATION
                                 -------------


2.1        Eligibility

           Except in the case of the  Initial  Offering,  each  person who is an
Eligible  Employee on an Offering Date may become a Participant by executing and
filing a Stock Purchase  Agreement at least 15 days prior to said Offering Date.
In the case of the Initial Offering,  each person who is an Eligible Employee on
the Initial  Offering  Date may become a  Participant  by executing and filing a
Stock  Purchase  Agreement on or before the date  determined by the Committee in
accordance  with  applicable law. An Employee may not participate in the Plan if
immediately  after the  applicable  Offering Date or, in the case of the Initial
Offering,  the Initial  Offering Date, the Employee would be deemed for purposes
of Section  423(b)(3)  of the Code to  possess 5% or more of the total  combined
voting  power or  value  of all  classes  of  stock  of the  Corporation  or any
Subsidiary.  Notwithstanding  the foregoing,  the eligibility of any Participant
who is a Covered  Officer is further  limited to the extent  provided in Article
VI.


2.2        Payroll Deductions

           Payment for shares of Common Stock purchased  hereunder shall be made
by authorized payroll deductions from each payment of Compensation in accordance
with instructions  received from a Participant.  Payroll deductions (a) shall be
equal to at least 1% of  Compensation  and (b) must equal at least five  dollars
($5.00)  per pay period and (c) may be  expressed  either as (i) a whole  number
percentage or (ii) a fixed dollar  amount,  subject to the provisions of section
3.3 hereof.  A Participant may not increase or decrease the deduction  during an
Option Period. A Participant may, however,  change the percentage  deduction for
any subsequent Option Period by filing another Stock Purchase Agreement at least
15 days  prior to the  Offering  Date on which  such  subsequent  Option  Period
commences.  Amounts deducted from a Participant's  Compensation pursuant to this
Section 2.2 shall be credited to the Participant's Plan Account.


                                   ARTICLE III
                                   -----------
                               PURCHASE OF SHARES
                               ------------------


3.1        Option Price

           The Option Price per share of the Common  Stock sold to  Participants
hereunder shall be 85% of the Fair Market Value of such share on (i) in the case
of the Initial  Offering,  either the Initial Offering Date or the Exercise Date
of the Option Period, whichever is lower, or (ii) in all other cases, either the
Offering Date or the Exercise Date of the Option Period, whichever is lower, but
in no event  shall the Option  Price per share be less than the par value of the
Common Stock.


3.2        Purchase of Shares

           On each Exercise  Date,  the amount in a  Participant's  Plan Account
shall be charged with the aggregate  Option Price of the largest number of whole
shares of Common Stock which can be purchased with said amount. The balance,  if
any,  in such Plan  Account  shall be  carried  forward  to the next  succeeding
Offering  Period,  unless the  Participant has elected to withdraw from the Plan
pursuant to Section 5.1 hereof.




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3.3        Limitations on Purchase

           The Fair Market Value (determined on the Offering Date or the Initial
Offering  Date, as the case may be) of the number of shares of Common Stock that
may be purchased  under the Plan by a Participant in any calendar year shall not
exceed $25,000.


3.4        Transferability of Rights

           Rights to  purchase  shares of Common  Stock  hereunder  shall not be
transferable otherwise than by will or the laws of descent and distribution, and
may be exercised during the Participant's lifetime only by the Participant.


                                   ARTICLE IV
                                   ----------
                       PROVISIONS RELATING TO COMMON STOCK
                       -----------------------------------


4.1        Common Stock Reserved

           There  shall be  300,000  authorized  and  unissued  shares of Common
Stock,  reissued  treasury  shares of Common  Stock,  or shares of Common  Stock
otherwise  acquired  by the  Corporation,  reserved  for the  Plan,  subject  to
adjustment in accordance with Section 4.2 hereof. The aggregate number of shares
which may be  purchased  under the Plan  shall not  exceed  the number of shares
reserved for the Plan.


4.2        Adjustment for Changes in Common Stock

           In the event that  adjustments  are made in the number of outstanding
shares of Common  Stock or the shares are  exchanged  for a  different  class of
stock of the  Corporation  or for  shares of stock of any other  corporation  by
reason of merger,  consolidation,  stock dividend, stock split or otherwise, the
Committee may make appropriate adjustments in (i) the number and class of shares
or other  securities that may be reserved for purchase  hereunder,  and (ii) the
Option Price. All such  adjustments  shall be made in the sole discretion of the
Committee, and its decision shall be binding and conclusive.


4.3        Insufficient Shares

           If the aggregate  funds available for the purchase of Common Stock on
any  Exercise  Date would  cause an  issuance  of shares in excess of the number
provided  for in Section 4.1 hereof,  (i) the  Committee  shall  proportionately
reduce  the  number  of  shares  that  would  otherwise  be  purchased  by  each
Participant  in order  to  eliminate  such  excess,  and  (ii)  the  Plan  shall
automatically terminate immediately after such Exercise Date.


4.4        Confirmation

           Each purchase of Common Stock hereunder shall be confirmed in writing
to the  Participant.  A record of purchases  shall be maintained by  appropriate
entries on the books of the  Corporation.  Except as provided in Article VI with
respect  to  Covered   Officers,   Participants  may  obtain  a  certificate  or
certificates  for all or part of the shares of Common Stock purchased  hereunder
by requesting same in writing.


4.5        Rights as Shareholders

           The shares of Common Stock  purchased by a Participant on an Exercise
Date  shall,  for all  purposes,  be deemed to have been  issued and sold at the
close of business on such Exercise Date.  Prior to that time, none of the rights
or privileges of a stockholder  of the  Corporation  shall exist with respect to
such shares.



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                                    ARTICLE V
                                    ---------
                          TERMINATION OF PARTICIPATION
                          ----------------------------


5.1        Voluntary Withdrawal

           A Participant may withdraw from the Plan at any time by filing notice
of  withdrawal  prior  to the  close  of  business  on an  Exercise  Date.  Upon
withdrawal,  the entire amount, if any, in a Participant's Plan Account shall be
refunded  to him or  her,  unless  the  Participant  elects  in such  notice  of
withdrawal  to have such amount used to purchase  whole  shares of Common  Stock
pursuant to Section 3.2 hereof on said  Exercise  Date,  and have any  remaining
balance  refunded.  Except as  provided  in Article  VI with  respect to Covered
Officers,  any  Participant  who  withdraws  from the Plan  may  again  become a
Participant in accordance with Section 2.1 hereof.



5.2        Termination of Eligibility

           If a  Participant  retires,  he or she may elect to (i)  withdraw the
entire amount, if any, in his or her Plan Account,  or (ii) have the amount used
to purchase  whole shares of Common Stock  pursuant to Section 3.2 hereof on the
next succeeding Exercise Date, and have any remaining balance refunded.

           If a Participant  ceases to be eligible  under Section 2.1 hereof for
any reason other than retirement,  the dollar amount in such  Participant's Plan
Account will be refunded  and,  except as provided in Article VI with respect to
Covered  Officers,  the number of  unissued  shares in such  Participant's  Plan
Account  will  be  distributed  to the  Participant  or  his  or her  designated
beneficiary or estate.


                                   ARTICLE VI
                                   ----------
                       SPECIAL RULES FOR COVERED OFFICERS
                       ----------------------------------



6.1        Withdrawal From Plan

           Unless permitted by the Committee,  if a Participant who is a Covered
Officer withdraws from the Plan (i.e., ceases participation), he or she will not
again be eligible to  participate in the Plan until the expiration of six months
from the  effective  date of the  notice  of  withdrawal.  In the  event of such
withdrawal,  the entire amount, if any, in the Participant's  Plan Account shall
be  refunded  to him or her,  unless  the  Participant  elects in the  notice of
withdrawal  to purchase  shares of Common Stock at the end of the Option  Period
and have the balance,  if any, in the  Participant's  Plan Account  refunded (in
such case, the effective  date of the notice of withdrawal  will be the Exercise
Date).


6.2        Obtaining Certificates for Common Stock

           Unless otherwise  permitted by the Committee,  a Participant who is a
Covered  Officer shall not be permitted to receive a certificate or certificates
representing  shares of Common Stock held in his or her Plan  Account  until the
expiration  of six  months  from the  Exercise  Date on  which  the  shares  are
purchased.  If  such  a  Participant  withdraws  from  the  Plan  (i.e.,  ceases
participation) or the Plan terminates,  and the Participant has shares of Common
Stock in his or her Plan  Account  that  have not been  held for such  six-month
period,  no certificates for the shares will be issued to the Participant  until
the end of that  six-month  period  unless  the  Committee  so  permits.  Unless
permitted by the Committee,  if a Participant who is a Covered Officer wishes to
receive a certificate or certificates  representing  shares of Common Stock that
have  been  held  in his or her  Plan  Account  for at  least  six  months,  the
Participant also must withdraw from the Plan (i.e.,  cease  participation) as of
the date the  certificate  or  certificates  are  issued  and will not  again be
eligible to participate in the Plan until the expiration of six months from that
date.




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6.3        Qualification under Code Section 423

           Should any provision of this Article VI cause the Plan not to qualify
as an "employee  stock  purchase  plan" within the meaning of Section 423 of the
Code,  then such provision  shall not be a requirement  under the Plan and shall
instead be a guideline that each  Participant  who is a Covered Officer is urged
to follow in order to avoid possible  liability to the  Corporation  pursuant to
Section 16(b) of the Exchange Act with respect to transactions under the Plan.


                                   ARTICLE VII
                                   -----------
                               GENERAL PROVISIONS
                               ------------------



7.1        Broad Based, Nondiscriminatory Plan

           The Plan shall at all times be a broad based,  nondiscriminatory plan
within the meaning of Rule 16b-3(d)(2)(i)(A) under the Exchange Act.


7.2        Notices

           Any notice  that a  Participant  files  pursuant to the Plan shall be
made on forms  prescribed by the Committee and,  except with respect to a notice
of  withdrawal  that is intended to take effect  after the purchase of shares of
Common Stock at the end of the Option  Period (see Section 5.1 above),  shall be
effective when received by AMSC Benefits Administration.


7.3        Condition of Employment

           Neither the creation of the Plan nor  participation  therein shall be
deemed to create  any right of  continued  employment  or in any way  affect the
right of the Corporation or a Subsidiary to terminate an Employee.


7.4        Amendment of the Plan

           The Board of Directors may at any time,  or from time to time,  amend
the Plan in any respect,  except that, without approval of the stockholders,  no
amendment may increase the aggregate  number of shares  reserved  under the Plan
other than as provided in Section 4.2 hereof,  materially  increase the benefits
accruing to  Participants,  or modify the  requirements  as to  eligibility  for
participation  in the Plan. Any amendment of the Plan must be made in accordance
with applicable provisions of the Code and/or any regulations issued thereunder.


7.5        Application of Funds

           All funds received by the Corporation by reason of purchase of Common
Stock hereunder may be used for any corporate purpose.


7.6        Legal Restrictions

           The Corporation shall not be obligated to sell shares of Common Stock
hereunder if counsel to the Corporation  determines that such sale would violate
any applicable law or regulation.


7.7        Governing Law

           The Plan and all rights and obligations thereunder shall be construed
and enforced in accordance with the laws of the State of Delaware.


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