EXHIBIT 10.58


                          LEASE SUPPLEMENT NUMBER FOUR


                  THIS LEASE SUPPLEMENT NUMBER FOUR (the "Lease Supplement"),
dated as of September 10, 2003, among WACHOVIA BANK, NATIONAL ASSOCIATION, as
successor to FIRST UNION NATIONAL BANK, not in its individual capacity but
solely as Trustee ("Lessor"), AIRLEASE LTD., a California limited partnership
("Owner Participant") and CSI AVIATION SERVICES, INC., a New Mexico corporation
("Lessee"; and together with Lessor and Owner Participant, the "Parties").

                               W I T N E S S E T H

                  WHEREAS, the Parties have heretofore entered into those two
certain Aircraft Lease Agreements, each dated as of November 21, 2001, that
certain Lease Supplement Number Two, dated as of October 9, 2002 and that
certain Lease Supplement Number Three, dated April 9, 2003 pertaining to two
McDonnell Douglas DC-9 Series 82 aircraft with respective registration numbers
N806US and N807US and respective manufacturer's serial numbers 48038 and 48039
(each, as amended, modified or supplemented prior to the date hereof, herein
called a "Lease" and collectively the "Leases" and the terms defined therein
being herein used with the same meanings unless otherwise defined herein); and

                  WHEREAS, the Parties desire to amend the Leases as set forth
herein;

                  NOW, THEREFORE, in consideration of the premises and other
good and sufficient consideration, the Parties hereby agree as follows:

                  1. The definition of "Basic Rent Amount" in Schedule 2 of each
Lease shall be amended to read as set forth on Schedule 1 hereto.

                  2.  Clause (b) of Section  3.1 in each Lease  shall be deleted
and replaced with the following text:

                           Lessee shall have the right to terminate the leasing
                           of the Aircraft under this Lease (i) on or after the
                           date on which the USMS Agreement is terminated by
                           delivering to Lessor and Owner Participant not later
                           than 30 days before such date a written notice
                           specifying that the leasing of the Aircraft is to
                           terminate on such date pursuant to this Section
                           3.1(b) or (ii) provided the Other Lease has not been
                           terminated, on any date by delivering to Lessor and
                           Owner Participant not later than 30 days before such
                           date a written notice specifying that the leasing of
                           the Aircraft is to terminate on such date pursuant to
                           this Section 3.1(b).

                  3. Lessee hereby makes the following representations and
warranties:

                  (a) Lessee is a corporation duly organized and validly
existing in good standing under the laws of the State of New Mexico and has the
corporate power and authority to carry on its business as presently conducted
and to perform its obligations under the Leases and this Lease Supplement and
the other Lessee Documents and is duly qualified to do business as a






foreign corporation in each jurisdiction in which the nature of its business
makes such qualification necessary;

                  (b) this Lease Supplement has been duly authorized by all
necessary corporate action on the part of Lessee, does not require any approval
of the stockholders of Lessee or any trustee or any holder of any indebtedness
of Lessee, and neither the execution and delivery hereof nor the consummation of
the transactions contemplated hereby nor compliance by Lessee with any of the
terms and provisions hereof will contravene its organizational documents or any
law or governmental rule or regulation applicable to Lessee or result in any
breach of, or constitute any default under, or result in the creation of any
Lien upon any property of Lessee under any indenture, mortgage, credit agreement
or other agreement or instrument to which Lessee is a party or by which Lessee
or its properties or assets may be bound;

                  (c) this Lease Supplement has been, and upon execution and
delivery of such Lease Supplement will be, duly executed and delivered by Lessee
and constitutes or will constitute the legal, valid, and binding obligations of
Lessee, enforceable in accordance with its terms; and

                  (d) no Lease Event of Default or Lease Default has occurred
and is continuing under either Lease.

                  4. Lessor hereby makes the following representations and
warranties:

                  (a) Trust Company is a national banking association duly
organized and validly existing under the laws of the United States of America,
and this Lease Supplement has been executed by an officer of Trust Company who
is duly authorized to do so in accordance with the terms of the Trust Agreement.

                  (b) The Trust Agreement is in full force and effect and Lessor
is duly and properly authorized to execute and deliver this Lease under the
Trust Agreement.

                  (c) This Lease Supplement has been, and upon execution and
delivery of such Lease Supplement will be, duly executed and delivered by Lessor
and constitutes or will constitute the legal, valid, and binding obligations of
Lessor, enforceable in accordance with its terms.

                  5. Sections 16 and 20 of each Lease are hereby incorporated by
reference in this Lease Supplement mutatis mutandis, on and as of the date of
this Lease Supplement, to the same extent as if fully set forth herein.

                  6. Save as expressly amended herein, the Leases as amended
hereby shall continue to be, and shall remain, in full force and effect in
accordance with their terms.

                                      * * *





                  IN WITNESS WHEREOF, the Parties have caused this Lease
Supplement Number Four to be duly executed and delivered as of the date and year
first above written.



                                            WACHOVIA BANK, NATIONAL ASSOCIATION,
                                               as successor to First Union
                                               National Bank, not in its
                                               individual capacity, but solely
                                               as Trustee, as Lessor

                                            By: ________________________________
                                                Name:
                                                Title:


                                            AIRLEASE, LTD.
                                               as Owner Participant

                                            By: ________________________________
                                                Name:
                                                Title:


                                            CSI AVIATION SERVICES, INC.
                                               as Lessee

                                            By: ________________________________
                                                Name:
                                                Title:





                                   SCHEDULE 1


"Basic Rent Amount" means (i) $125,000 on each Rent Payment Date before
September 10, 2002, (ii) $108,500 on September 10, 2002, (iii) $70,000 on each
Rent Payment Date after September 10, 2002 but before March 10, 2003, (iv)
$60,000 on March 10, 2003 and each Rent Payment Date after March 10, 2003 but
before September 10, 2003, (v) $40,500 on September 10, 2003, (vi) $45,000 on
each Rent Payment Date after September 10, 2003 but prior to the Termination
Date of the Other Lease, (vii) on the Termination Date of the Other Lease, an
amount equal to the product of $15,000 and a fraction, the numerator of which is
the number of days from and including the Termination Date of the Other Lease to
but excluding the next Rent Payment Date, and the denominator of which is 30 and
(viii) $60,000 on each Rent Payment Date thereafter.

                                      * * *