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                                 EXHIBIT 10.7(B)

                  ASSIGNMENT, ASSUMPTION AND RELEASE AGREEMENT
                         (LEARJET 45, SERIAL NUMBER 053)


         THIS ASSIGNMENT, ASSUMPTION AND RELEASE AGREEMENT (this "Agreement")
dated February 17, 1999 by and among TEXACO INC., a Delaware corporation, having
an office at 2000 Westchester Avenue, White Plains, New York 10650 ("Assignor"),
TRC REALTY CO., a Vermont corporation, having an office at One Pierce Place,
Suite 100E, Itasca, Illinois 60143 ("Assignee"), and LEARJET INC., a Delaware
corporation, having an office at One Learjet Way, Wichita, Kansas 67277
("Learjet").

         WHEREAS, Assignor and Learjet have entered into an Airplane Purchase
Agreement dated January 21, 1994 (the "Airplane Purchase Agreement") providing
for the sale by Learjet to Assignor of one Learjet Model 45, Serial No. 053 (the
"Aircraft"); and

         WHEREAS, Assignor wishes to assign to Assignee all of Assignor's right,
title and interest in, to an under the Airplane Purchase Agreement and Assignee
is willing to accept such assignment, as hereinafter set forth.

         NOW, THEREFORE, in consideration of the premises and other valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties hereto agree as follows:

         1. Assignment. Subject to Section 8, Assignor hereby sells, conveys,
assigns, transfers, sets over, and delivers unto Assignee, all of the Assignor's
right, title and interest in, to and under the Airplane Purchase Agreement
including without limitation, (i) all claims for damages in respect of the
Aircraft arising against the manufacturer under the Airplane Purchase Agreement,
whether arising as a result of a default by the manufacturer or otherwise,
including all warranty and indemnity provisions contained in the Airplane
Purchase Agreement, and all claims arising thereunder in respect of the
Aircraft, (ii) any and all rights of the Assignor to compel performance of the
terms of the Airplane Purchase Agreement in respect of the Aircraft, and (iii)
the right to receive all credits, rebates, adjustments and discounts, if any,
due to the Assignor with respect to the purchase price of the Aircraft pursuant
to the Airplane Purchase Agreement (the "Assignment").

         2. Assumption. Subject to Section 8, Assignee hereby accepts the
Assignment from Assignor, and expressly assumes the due and punctual performance
and observance of each covenant, condition and obligation of Assignor under the
Airplane Purchase Agreement (the "Assumption"). Without limiting any of the
terms hereof, Assignee acknowledges and agrees that the March 1993 Aircraft
Specifications are applicable under the Airplane Purchase Agreement.

         3. Acceptance by Learjet. Learjet hereby accepts and agrees to the
Assignment and the Assumption.

         4. Acknowledgement by Learjet. Learjet hereby agrees and acknowledges
that:

         (i) as of the date hereof, Assignor has made payments to Learjet under
             the Airplane Purchase Agreement in amounts equal to One Million
             Dollars ($1,000,000.00), such


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                  amounts having been paid in Fuel Purchase Credits under the 
                  Airplane Purchase Price and Fuel Purchase Price Payment
                  Agreement referred to in the Airplane Purchase Agreement;

         (ii)     as of the date hereof, Assignor is in compliance with all of
                  the terms and conditions under the Airplane Purchase Agreement
                  and no default by Assignor under the Airplane Purchase
                  Agreement has occurred or is continuing;

         (iii)    from and after the date hereof, Assignee shall be deemed to be
                  a party to the Airplane Purchase Agreement in the same right
                  and capacity as Assignor and shall be entitled to all rights,
                  benefits and privileges of Assignor arising thereunder or in
                  connection therewith, in each case to the same extent as if
                  Assignee were expressly named as a party therein, subject to
                  Section 8; and

         (iv)     the Airplane Purchase Agreement is in full force and effect 
                  and is enforceable in accordance with its terms.

         5. Release by Learjet. Learjet hereby releases, acquits and forever
discharges Assignor from and of each covenant and condition of, and each
liability or other obligation arising under, the Airplane Purchase Agreement to
be observed or performed by Assignor pursuant to the terms thereof and Assignor
shall no longer be bound by, or have any obligation or liability in respect of,
the Airplane Purchase Agreement.

         6. Preservation of Learjet's Rights under the Airplane Purchase
Agreement. Nothing contained herein shall subject Learjet to any liability to
which it would not otherwise be subject under the Airplane Purchase Agreement or
modify in any respect Learjet's contract rights thereunder or require Learjet to
divest itself of title to the Aircraft under the Airplane Purchase Agreement
until the Delivery Date (as defined in the Airplane Purchase Agreement) for the
Aircraft and payment thereof as provided therein, provided that Learjet shall
take no action under the Aircraft Purchase Agreement that is inconsistent with
the agreements and acknowledgements contained in this Agreement.

         7. No Aircraft sale or Warranties, Etc. NOTWITHSTANDING ANYTHING TO THE
CONTRARY IN THIS AGREEMENT, ASSIGNOR IS NOT THE SELLER OF THE AIRCRAFT, WHICH IS
SOLD SOLEY PURSUANT TO THE AIRPLANE PURCHASE AGREEMENT. THERE ARE NO EXPRESS OR
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
OTHERWISE BY ASSIGNOR. IN NO EVENT SHALL ASSIGNOR BE LIABLE (A) IN WARRANTY,
NEGLIGENCE OR STRICT LIABILITY REGARDING ANY DEFECTS, FAILURES OR MALFUNCTIONS
IN PERFORMANCE, DESIGN, MANUFACTURE OR OTHERWISE, OR (B) FOR ANY DAMAGES
(WHETHER DIRECT, CONSEQUENTIAL, INCIDENTAL, PUNITIVE, INDIRECT, SPECIAL OR
OTHERWISE) ARISING OUT OF THE SALE, USE OR OPERATION OF THE AIRCRAFT, REGARDLESS
OF LEGAL THEORY OR NEGLIGENCE.


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         8.  Expected Terms. Notwithstanding anything to the contrary in this
Agreement, from and after the date hereof, (i) Assignee and Learjet shall have
no rights or obligations under or with respect to Exhibit C to the Airplane
Purchase agreement, (ii) Assignee shall have no rights or obligations under or
with respect to the agreements listed in paragraph 4 of Exhibit B to the
Airplane Purchase Agreement, and (iii) each reference to "Fuel Purchase Credits"
in the Airplane Purchase Agreement shall be solely to the amounts referred to in
Section 4(i) hereof.

         9.  Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the Sate of New York without regard to the conflict
of laws principles thereof.

         10. Dispute Resolution. Any claim, controversy or dispute among the
parties hereto arising out of, relating to, or in connection with this
Agreement, including the interpretation, validity, termination or breach hereof,
that cannot be settled amicably, shall be resolved in accordance with the
arbitration provisions set forth in the Airplane Purchase Agreement which are
hereby incorporated by reference.

         11. Further Assurances. The parties shall execute and deliver to each
other such further documents and take such further action as may be reasonably
requested by any party to document, complete or give full effect to the terms
and provisions of this Agreement and the transactions contemplated herein.

         12. Entire Agreement. As between Assignor and Learjet, this Agreement
contains the entire agreement between assignor and Learjet with respect to the
transactions contemplated hereby and all prior or contemporaneous understandings
and agreements between Assignor and Learjet with respect to such subject matter
are hereby superceded.

         13. Counterparts. This Agreement may be executed in one or more
counterparts each of which shall be deemed an original and all of which shall be
deemed one and the same instrument.

                         [Signatures on following page]


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         IN WITNESS WHEREOF, this Agreement has been duly executed as of the day
and year first above written.


                                   TEXACO INC.


                                   By: /s/ Donald E. Baldwin
                                       -----------------------------------------
                                       Name:   Donald E. Baldwin
                                       Title:  Manager
                                               Aviation Transport Services


                                   TRC REALTY CO.


                                   By: /s/ Donald F. Wiseman       
                                       -----------------------------------------
                                       Name:   Donald F. Wiseman
                                       Title:  Vice President, General Counsel &
                                               Secretary


                                   LEARJET INC.


                                   By: /s/ Linda Meyer                   
                                       -----------------------------------------
                                       Name:   Linda Meyer
                                       Title:  Director of Contracts




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