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                                                                   EXHIBIT 10.30



[GRAPHIC OMITTED]
[Motient Logo]


                                  CONFIDENTIAL

February 10, 2004

Walter V. Purnell, Jr.
[OMITTED]


Dear Walt:

                  The purpose of this letter is to define the terms of your
separation from employment with Motient Corporation, to settle any claims under
that certain Executive Retention Agreement, dated as of July 16, 2002, by and
between Motient Corporation and you ("Retention Agreement"), and to set out
certain arrangements with respect to your separation. In consideration of the
mutual covenants herein contained, and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties agree
as follows:


1.                  Termination of Employment:

                    a.   You are hereby relieved of all your duties effective
                         immediately, but your termination date shall be March
                         11, 2004.

                    b.   Effective immediately, you agree to, and hereby do,
                         resign from the boards of directors of Motient
                         Corporation, and all its subsidiaries and affiliates.

                    c.   You also hereby agree to resign from Mobile Satellite
                         Ventures GP Inc. and all its subsidiaries and
                         affiliates, provided, however, that such resignation
                         shall not be delivered until the earlier of (x) the
                         appointment by Motient of a successor director, or (y)
                         such earlier date upon which Motient determines to
                         render such resignation effective.

2.                  Settlement of Executive Retention Agreement:

                    a.   You will receive a continuing severance payment of an
                         amount equal to one-half of your current base salary
                         for the next eighteen months. This severance payment
                         amount shall be paid in bi-weekly installments in
                         accordance with the Company's normal payroll schedule
                         for active employees.

                    b.   On September 11, 2005, you will also receive an
                         additional lump sum severance payment of an amount
                         equal to the sum total of all amounts required to be
                         paid out pursuant to paragraph 2(a) above. .

                    c.   You will continue to be eligible for the standard
                         health benefits package made available to all employees
                         over the next eighteen months.

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                    d.   If you participate in a health care flexible spending
                         account, you may continue to submit claims for
                         reimbursement for expenses incurred through your last
                         day of employment up to three months following the end
                         of the current plan year. If you have not incurred
                         expenses prior to your last day of employment, you may
                         continue monthly after-tax contributions up to the end
                         of the current plan year. This will keep your account
                         open for reimbursement of health care expenses incurred
                         after your separation date. If we do not receive
                         continued after-tax contributions within 60 days of
                         your last day of employment, your plan year will end on
                         such date.

                    e.   If you participate in a dependent care flexible
                         spending account, you can submit request for
                         reimbursement up to 3 months following the end of your
                         current plan year. Expenses are eligible only if you
                         (and your spouse if your are married) are working or
                         seeking employment. No additional after-tax
                         contributions to your account will be allowed.

                    f.   If you have a 401(k) account and your vested balance is
                         greater than $3,500, you may keep your account with
                         CIGNA. If your vested account balance is less than
                         $3,500, you must withdraw or rollover your 401(k)
                         balance within a specified time frame. Withdrawals are
                         subject to relevant I.R.S. limitations and penalties.
                         Any outstanding loans must be paid back directly to
                         CIGNA, or they are otherwise considered cash
                         distributions subject to applicable taxes and
                         penalties. Please contact CIGNA at 1-800-253-2287 for
                         information on future account transactions.

                    g.   Your accrued PTO will be paid out in a lump sum on the
                         next practicable pay date following your last day with
                         Motient.

                    h.   Your reimbursable expenses will be paid out in a lump
                         sum on the next practicable pay date following your
                         last day with Motient.

                    i.   Any stock options issued pursuant to Motient's 2002
                         Stock Potion plan will be subject to the terms of such
                         plan, and to the award grant under which they were
                         issued.

3.                  In consideration of the above, you agree to the following:

                    a.   You will support Motient publicly and not take any
                         action or make any statement that would detract from
                         Motient's image or ability to carry on its business.
                         Motient agrees not to disparage you.

                    b.   You agree to sign the attached Exhibit A, Waiver and
                         Release Agreement, which form was substantially agreed
                         to as part of the Retention Agreement, and the terms
                         and conditions of which are specifically incorporated
                         herein by reference.

                    c.   You agree to sign the attached Exhibit B, Non-Compete
                         and Non-Solicit Agreement, which form was substantially
                         agreed to as part of the Retention Agreement, and the
                         terms and conditions of which are specifically
                         incorporated herein by reference.

                    d.   You agree to sign and immediately deliver the attached
                         Exhibit C, a Resignation from the board of directors of
                         Motient Corporation and all its subsidiaries and
                         affiliates. Note that the non-execution or non-delivery
                         of this resignation will not nullify your immediate
                         resignation from Motient Corporation and all its
                         subsidiaries pursuant to paragraph 1(b) above.
<PAGE>

                    e.   You agree to sign and deliver, upon Motient's request,
                         the attached Exhibit D, a Resignation from the board of
                         directors of Mobile Satellite Ventures GP Inc., and all
                         its subsidiaries and affiliates.

                    f.

                    (i)  For a period of three (3) years thereafter, and in
                         keeping with Motient policy, you agree not to use,
                         disclose, or copy Confidential Information, as defined
                         in item (ii) of this paragraph 2(b), or in any other
                         way publicly or privately disseminate Confidential
                         Information, or help anyone else to do any of these
                         things, except as otherwise required by law.

                    (ii) For purposes of this letter, "Confidential Information"
                         means all information or data, of any nature and in any
                         form, whether written, oral, or in any other form, or
                         recorded or transmitted electronically or by tape or
                         any other manner or medium, regarding or relating to
                         the business, operations, prospects, plans, or affairs
                         of Motient which is not generally known to the public.

                    g.   As soon as is reasonably practicable, you agree to
                         return all Motient property in your possession,
                         including but not limited to documents, data and
                         information concerning Motient.

                    h.   In the event of any question or disagreement between
                         you and Motient as to the nature and extent of this
                         Agreement, you agree to meet upon request at a
                         reasonable time and place with Motient management to
                         discuss and attempt in good faith to resolve such
                         question or disagreement.

This letter constitutes the entire agreement between you and Motient with
respect to your separation, and it supersedes any other discussion,
negotiations, commitments or understandings, whether written or oral. It may not
be altered, modified, or amended except in writing and signed by you and
Motient's President, General Counsel or me.

You should feel free to discuss the terms of this letter with an attorney of
your choice before executing it. After you have had an opportunity to carefully
consider it, please sign this letter and return it to me. Please also retain a
copy for your files.

Sincerely,


----------------------
Steven Singer
Chairman of the Board
Motient Corporation


AGREED AND ACCEPTED



------------------------
Walter V. Purnell, Jr.


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                                    EXHIBIT A
                          WAIVER AND RELEASE AGREEMENT


         This Waiver and Release Agreement is in consideration of the severance
pay and benefits provided to me by Motient Corporation (the "Company"), in
accordance with that certain Agreement, dated as of July 16, 2002, by and
between me and the Company and providing for a severance payment, as such
agreement is modified and amended by that certain letter agreement, dated as of
February 10, 2004, by and between me and the Company.

         The payments and benefits described above are referred to herein
collectively as the "Severance Payment." I acknowledge and agree that I would
not be entitled to the Severance Payment without entering into this Waiver and
Release Agreement, and I voluntarily enter into this Waiver and Release
Agreement.

         I, on my own behalf and on behalf of my heirs, executors,
administrators, attorneys and assigns, hereby unconditionally and irrevocably
release, waive and forever discharge the Company and each of its affiliates,
parents, successors, predecessors, and the subsidiaries, directors, owners,
members, shareholders, officers, agents, and employees of the Company and its
affiliates, parents, successors, predecessors, and subsidiaries (collectively
all of the forgoing are referred to as the "Employer"), from any and all causes
of action, claims and damages, including attorneys' fees, whether known or
unknown, foreseen or unforeseen, presently asserted or otherwise arising through
the date of my signing of the Waiver and Release Agreement, concerning my
employment or separation from employment. This release includes, but is not
limited to, any claim or entitlement to salary, bonuses, any other payments,
benefits or damages arising under any federal law (including but not limited to,
Title VII of the Civil Rights Act of 1964, the Age Discrimination in Employment
Act, the Employee Retirement Income Security Act of 1974 (namely, "ERISA"), the
Americans with Disabilities Act, and the Family and Medical Leave Act, each as
amended); any claim arising under any state or local ordinances or regulations;
and any claim arising under any common law principle or public policy, including
but not limited to all suits in tort or contract, such as, wrongful termination,
defamation, emotional distress, invasion of privacy or loss of consortium.
Notwithstanding the preceding, this Waiver and Release agreement shall not apply
with respect to a claim under ERISA for benefits accrued but not paid under an
ERISA Plan.

         I understand that by signing this Waiver and Release Agreement I am not
waiving any claims or administrative charges which cannot be waived by law. I am
waiving, however, any right to monetary recovery or individual relief should any
federal, state or local agency (including the Equal Employment Opportunity
Commission (the "EEOC")) pursue any claim on my behalf arising out of or related
to my employment with and/or separation from employment with the Employer.

         I further agree, without any reservation whatsoever, never to sue the
Employer or become a party to a lawsuit on the basis of any and all claims of
any type lawfully and validly released in this Waiver and Release Agreement. If
I sue in violation of the preceding sentence of this Waiver and Release
Agreement, I will (1) pay all costs and expenses incurred by the Employer in
defending against a suit or enforcing this Waiver and Release Agreement,
including litigation and court costs, expenses and reasonable attorneys' fees,
and (2) I will repay the Severance Payment I received in consideration for this
Waiver and Release Agreement.

         I am signing this Waiver and Release Agreement knowingly and
voluntarily. I acknowledge that:

         (1)      I am hereby advised in writing to consult an attorney before
                  signing this Waiver and Release Agreement;

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         (2)      I have relied solely on my own judgment and/or that of my
                  attorney regarding the consideration for and the terms of this
                  Waiver and Release Agreement and am signing this Waiver and
                  Release Agreement knowingly and voluntarily of my own free
                  will;

         (3)      I am not entitled to the Severance Payment amount unless I
                  agree to and honor the terms of this Waiver and Release
                  Agreement.

         (4)      I have been given at least twenty-one (21) days to consider
                  this Waiver and Release Agreement;

         (5)      I may revoke this Waiver and Release Agreement within seven
                  (7) days after signing it by submitting a written notice of
                  revocation to the Company's Human Resources Director, Elyse
                  Ward. I further understand that this Waiver and Release
                  Agreement is not effective or enforceable until after the
                  seven (7) day period of revocation has expired without
                  revocation, and that if I revoke this Waiver and Release
                  Agreement, I will not receive any Severance Payment;

         (6)      I have read and understand the Waiver and Release Agreement
                  and further understand that it includes a general release of
                  any and all known and unknown, foreseen or unforeseen, claims
                  presently asserted or otherwise arising through the date of my
                  signing of this Waiver and Release Agreement that I may have
                  against the Employer; and

         (7)      No statements or conduct by the Employer have in any way
                  coerced or unduly influenced me to execute this Waiver and
                  Release Agreement.

         I further acknowledge that there are no other agreements of any nature
between the Employer and me with respect to the matters discussed in this Waiver
and Release Agreement, except as expressly stated herein, and that in signing
this Waiver and Release Agreement, I am not relying on any agreements or
representation, except those expressly contained in this Waiver and Release
Agreement and the Retention Agreement.

         I further acknowledge and agree that if any provision of this Waiver
and Release Agreement is found, held or deemed by a court of competent
jurisdiction to be void, unlawful or unenforceable under any applicable statute
or controlling law, the remainder of this Waiver and Release Agreement shall
continue in full force and effect.

         This Waiver and Release Agreement is deemed made and entered into in
         the State of Illinois, and in all respects shall be interpreted,
         enforced and governed under applicable federal law, and in the event
         that any reference shall be made to state law, the internal laws of the
         State of Illinois shall apply. Any disputes under this Waiver and
         Release Agreement shall be adjudicated by a court of competent
         jurisdiction in the State of Illinois.

                  I understand that, to receive the Severance Payment amount, I
must sign and return this Waiver and Release Agreement no sooner than my
employment termination date and no later than twenty-one (21) days from the date
my employment was terminated.



-----------------------------                  ------------------------
Date                                           Signature


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                                    EXHIBIT B
                      NON-COMPETE AND NON-SOLICIT AGREEMENT

         THIS NON-COMPETE AND NON-SOLICIT AGREEMENT ("Agreement") is entered
into between Motient Corporation (the "Company") and myself, the undersigned
employee of the Company effective as of the execution date set forth below. In
consideration of the severance payments to be provided to me under that certain
Agreement, dated as of July 16, 2002, by and between the Company and me, as such
agreement is modified and amended by that certain letter agreement, dated as of
February 10, 2004, by and between me and the Company, the sufficiency of which I
expressly acknowledge, the Company and I hereby agree, intending to be legally
bound, as follows:

1.       Employee Obligations

         1.1. No Solicitation of Employees. For twelve (12) months after my
employment with the Company is terminated, whether voluntarily or involuntarily,
I agree not to solicit, directly or indirectly, any of the Company's key
employees for employment with a person or entity involved in marketing or
developing products or services competitive with the Company's products or
services. Key employees include supervisory personnel, executives, personnel in
charge of any department, section or subdivision within the Company and project,
contract managers (or directors) and senior personnel on any individual project
or projects.

         1.2. No Unfair Competition. During my employment with the Company and
for a period of 18 months after the termination of my employment with the
Company, whether voluntarily or involuntarily, I agree that I shall not,
directly or indirectly, engage in or become interested in any Competing
Business, in connection with research, development, consulting, manufacturing,
purchasing, accounting, engineering, marketing, merchandising or selling of any
product or service which resembles or competes with a product or service of the
Company (hereafter, such engagement referred to as "Improper Engagement"). I
understand that I will have engaged in or become interested in a Competing
Business if, whether or not I am compensated, I become an employee, consultant,
advisor or agent of a Competing Business. I also understand that I will have
entered into an Improper Engagement if I become a stockholder owning
beneficially or of record more than five percent (5%) of the outstanding shares
of any class of stock of a Competing Business or a director, partner, joint
venturer or proprietor of a Competing Business. For purposes of this Agreement,
a "Competing Business" is an enterprise engaged in or about to become engaged
in, research on or development, production, marketing or selling of any product
or service which resembles or competes with a product or service of the Company.

         1.3 Fiduciary Duty not to Disclose Proprietary or Confidential
Information. During and after my employment with the Company, I agree to observe
the terms of the Intellectual Property and Confidential Information Agreement,
which I entered into with the Company upon accepting employment with the
Company. I understand and agree that, during and after my employment with the
Company, I shall hold in a fiduciary capacity for the benefit of the Company all
secret or confidential information, knowledge or data relating to the Company or
its affiliated companies and their respective businesses that I have obtained
during the course of my employment by the Company or any of its affiliate
companies that is not public knowledge.

2.       Nature of Relationship

         Nothing herein shall be construed as constituting an agreement,
understanding or commitment of any kind that the Company shall continue to
employ me, nor shall this Agreement limit in any way the Company's right to
terminate my employment at any time for any reason whatsoever, subject to
applicable laws and contracts.


<PAGE>

3.       Enforcement

         I acknowledge that in the event of my breach of any of the obligations
in this Agreement, the Company's business interests will be irreparably injured,
the full extent of the Company's damages will be impossible to ascertain,
monetary damages will not be an adequate remedy for the Company, and the Company
will be entitled to enforce this Agreement by an injunction or other equitable
relief, without the necessity of posting bond or security, which I expressly
waive. I understand that the Company may waive some of the requirements
expressed in this Agreement, but that such a waiver to be effective must be made
in writing by the Company senior management and should not in any way be deemed
a waiver of the Company's right to enforce any other requirements or provisions
of this Agreement. I agree that each of my obligations specified in this
Agreement is a separate and independent covenant that shall survive any
termination of this Agreement and that the unenforceability of any of them shall
not preclude the enforcement of any other covenants in this Agreement.

4.       General Terms

         This is my entire agreement with the Company with respect to its
subject matter and its date, superseding any prior oral or written, express or
implied negotiations and agreements, and its terms will be governed by the laws
of the Commonwealth of Virginia without regard to conflict of laws provisions.
The agreement may not be changed in any respect except by a written agreement
signed by both myself and an officer of the Company. If any provision of the
agreement is held to be invalid, illegal or unenforceable for any reason, the
validity, legality and enforceability of the remaining provisions will not in
any way be affected or impaired thereby.

         By my signature below, I acknowledge that I have reviewed this
Non-Compete and Non-Solicit Agreement carefully and understand that the
covenants and obligations it contains are binding on me.

                              Print Name:
                                         ---------------------------------
                              Date Signed:
                                          --------------------------------
                              Address:
                                      ------------------------------------
                              Social Sec. No:
                                             -----------------------------

Motient Corporation

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


<PAGE>




                                    Exhibit C

                                   RESIGNATION


TO:               Steven G. Singer
                  Chairman
                  Motient Corporation
                  Motient Holdings Inc.
                  Motient Communications Inc.
                  Motient Services Inc.
                  MVH Holdings Inc.
                  Motient Ventures Holdings Inc.


     I, Walter V. Purnell, Jr., hereby resign effective as of February 10th,
2004, as a Director of the following entities:

                  Motient Corporation
                  Motient Holdings Inc.
                  Motient Communications Inc.
                  Motient Services Inc.
                  MVH Holdings Inc.
                  Motient Ventures Holdings Inc.

     I do hereby further relinquish all power and authority conferred upon me by
     the By-laws of any of the above entities in my former position as a
     director.


                                            Sincerely,



                                            Walter V. Purnell, Jr.


DATED:  February 10, 2004


<PAGE>


                                    Exhibit D

                                   RESIGNATION


TO:               Dr. Carson E. Agnew,
                  President and COO
                  Mobile Satellite Ventures GP Inc.
                  10802 Parkridge Blvd.
                  Reston VA, 20191

AND TO:  Mobile Satellite Ventures LP

AND TO:  The following subsidiaries of MSV LP:
         Mobile Satellite Ventures Subsidiary LLC
         Mobile Satellite Ventures Corp.
         TerreStar Networks Inc.

AND TO:  The General and Limited Partners, Unit Holders, Stock Holders and
         Shareholders of MSV and its Subsidiaries


         I, Walter V. Purnell, Jr., hereby resign effective as of February 10th,
2004, as a Director of the following Mobile Satellite Ventures entities:

         Mobile Satellite Ventures GP Inc.;
         Mobile Satellite Ventures Corp.;
         Mobile Satellite Ventures Subsidiary LLC; and
         TerrreStar Networks Inc.

I do hereby further relinquish all power and authority conferred upon me by the
By-laws of any of the Mobile Satellite Ventures entities in my former position
as a director.


                                            Sincerely,



                                            Walter V. Purnell, Jr.


DATED:  February 10, 2004