Document:

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                                                                    Exhibit 10.6

                              AMENDED AND RESTATED
                           UNGER SEPARATION AGREEMENT

     This Amended and Restated Separation Agreement (this "Separation
                                                           ----------
Agreement") is made this 4th day of February, 2000, by and between PS Group,
Inc., a Delaware corporation (the "Company"), and Johanna Unger ("Employee"),
                                   -------                        --------
and is effective as of the 18th day of December, 1999, with reference to the
following facts:

     A.  Employee has served as Vice President and Controller of the Company
since March 1988.  Employee has also served as Vice President and Controller of
the Company's parent corporation, PS Group Holdings, Inc., a Delaware
corporation ("Holdings"), since 1996;
              --------

     B.  On December 18, 1999, Holdings entered into an Agreement and Plan of
Merger (the "Merger Agreement") with Heritage Air Holdings Statutory Trust, a
             ----------------
Connecticut statutory trust ("Parent"), and PSG Acquisition, Inc., a Delaware
                              ------
corporation ("Merger Sub"), providing for the merger of Merger Sub with and into
              ----------
Holdings (the "Merger"), as a result of which the stockholders of Holdings will
               ------
receive $12 per share for each of their shares and Holdings will become a
wholly-owned subsidiary of Parent;

     C.  Employee's employment with the Company and each of its affiliates, and
all of her directorships and offices with the Company and each of its
affiliates, will terminate at the effective time of the Merger (the "Effective
                                                                     ---------
Time");
----

     D.  The Board of Directors of Holdings has determined that Employee's
services to Holdings and its subsidiaries merit a payment to Employee of a
bonus, to be paid in accordance with the following provisions, if the Merger
occurs, in consideration for the Employee relinquishing, as of the Effective
Time, her rights under her Employment Agreement with the Company dated as of
April 18, 1988, as amended (the "Employment Agreement"), and her Split Dollar
                                 -------------------
Life Insurance Agreement with the Company dated as of January 1, 1986, as
modified by letter dated March 23, 1999 (the "Insurance Agreement"). To give
                                              -------------------
effect to such determination, concurrently with the execution of the Merger
Agreement, the Company, with the approval of its Board of Directors, entered
into a Separation Agreement dated December 18, 1999 (the "Original Agreement")
                                                          ------------------
with Employee; and

     E.  The Company and Employee now wish to amend and restate the Original
Agreement in its entirety.

     NOW THEREFORE, the Company and Employee hereby agree as follows:
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1.  Termination of Employment and Benefits.
    --------------------------------------

    (a)  At the Effective Time, the employment of Employee by the Company and
each of its affiliates, and all of Employee's directorships and offices with the
Company and each of its affiliates, shall automatically cease.

    (b)  At the Effective Time, all of Employee's rights under the Employment
Agreement and the Insurance Agreement shall lapse and those agreements shall
cease to be of any force and effect. As of the Effective Time, Employee
relinquishes all right and title in, and benefits under, the Insurance Agreement
and the insurance policy referred to therein.

2.  Bonus Payments.
    --------------

    (a)  In recognition of Employee's valuable contribution to the Company,
Holdings and their affiliates, and in light of the provisions of Section 1 of
this Separation Agreement, the Company shall pay Employee the following bonus
payments (each, a "Bonus Payment") if the Merger occurs:
                   -------------

         (i)  Immediately following the Effective Time, the Company shall pay
              Employee the sum of $335,000; and

         (ii) On the last day of each calendar month beginning with the month
              following the month in which the Effective Time occurs and ending
              on (and including) the twelfth calendar month, the Company shall
              pay Employee the sum of $16,750.

    (b)  No interest shall be payable on any Bonus Payment in respect of the
period prior to its due date hereunder.

    (c)  All Bonus Payments shall be subject to any deductions or withholdings
required by law.

    (d)  In the event of Employee's death prior to the payment of any Bonus
Payment, all subsequent Bonus Payments shall be paid, on their respective due
dates, to Employee's executor or administrator or to such other person as
Employee has theretofore specified in a signed document delivered to the
Company.

    (e)  Notwithstanding anything to the contrary in Sections 2(a), (b) and (d):
(i) the Company's obligation to make the Bonus Payments referred to in Section
2(a) shall be conditioned on Employee having executed, on or after the date on
which the Effective Time occurs, and not having thereafter revoked within the
revocation period specified therein, a Release substantially in the form of
Exhibit 1 to this Separation Agreement; and (ii) the Company's obligation to
make the final Bonus Payment referred to in Section

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2(a)(ii) shall be further conditioned on Employee having executed, not earlier
than 8 days before the due date of such final payment, and not having thereafter
revoked within the revocation period specified therein, a second Release
substantially in the form of said Exhibit 1.

    (f)  Anything in this Separation Agreement to the contrary notwithstanding,
if any amounts to be paid to Employee (or to her executor, administrator or
other payee specified by her) under this Separation Agreement, or any other
plan, agreement or program of the Company or any of its affiliates, would result
in a "parachute payment" (as defined in Section 280G(b)(2) of the Internal
Revenue Code of 1986, as amended (the "Code"), then the aggregate of such
                                       ----
"parachute payments" shall be reduced so that the aggregate of the amounts paid
to Employee which would otherwise constitute "parachute payments" will equal
three times Employee's "base amount" (as defined in Section 280G(b)(3) of the
Code) less $1.00. Any determination to be made under the preceding sentence
shall be made by an independent accounting firm with a nationally recognized tax
practice that has not performed services for the Company or any of its
affiliates, which firm shall be selected by the Company and be reasonably
acceptable to Employee, it being agreed that such accounting firm may not be the
Company's or Holdings' independent auditors. The Company agrees to pay the
accounting firm's fees and expenses with respect to any such determination.
Nothing herein shall limit the parties' respective rights in the event that an
applicable government taxing authority or court takes a position which is
inconsistent with any such determination.

    (g)  Nothing in this Separation Agreement shall affect Employee's right to
receive, when her employment by the Company terminates for any reason (whether
before or at the Effective Time), all vacation pay that has accrued under the
Company's existing vacation policy as applied to Employee.

3.  Confidentiality.
    ---------------

    Employee agrees that she will not use for her own benefit or disclose to
any third party, either during her employment or thereafter, any confidential
information or data concerning the business or activities of the Company, Parent
or any of their respective subsidiaries or affiliates acquired  at any time
while employed or rendering services to the Company or any of its subsidiaries
or affiliates, or any of their respective predecessors or successors.
Employee's obligations under this covenant and any liability for failure to
satisfy these obligations shall survive any termination of this Separation

Agreement.

4.  Termination.
    -----------
    This Separation Agreement shall terminate, and be null and void, in the
event that, prior to the Effective Time:

    (a)  The Merger Agreement is terminated pursuant to its terms; or

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    (b)  Employee's services as an employee of the Company cease for any reason
other than Employee's death or disability.

5.  Entire Agreement.
    ----------------

    This Agreement constitutes the entire agreement between the parties
concerning the subject matter hereof, and supercedes, as of the Effective Time,
all other written, oral or implied agreements between the parties including,
without limitation, the Employment Agreement and the Original Agreement.  The
Consulting Agreement dated December 18, 1999 between the Company and Employee
shall remain in full force and effect.  This Agreement may be modified or
amended only by a writing signed by both parties.

    IN WITNESS WHEREOF, the parties hereto have executed this Separation
Agreement as of the day and year first written above.

                              PS GROUP, INC.

                              By: /s/ Charles E. Rickershauser, Jr.
                                  ---------------------------------
                                  Charles E. Rickershauser, Jr.
                                  Chief Executive Officer

                              EMPLOYEE

                              /s/ Johanna Unger
                              -----------------
                              Johanna Unger

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                                                                       Exhibit 1

                            Release From All Claims

                             _______________, 2000

[Name]
[Title]
PS Group, Inc.
[Address]

Dear ______________:

     In consideration of the payment to me (or to my executor, administrator or
other payee designated by me in writing, in the event of my death), on their
respective due dates, of each Bonus Payment, I hereby release and discharge the
Company Parties (as defined below) from any and all claims, actions, causes of
action, suits, costs, controversies, judgements, decrees, verdicts, damages,
liabilities, attorneys' fees, covenants, contracts, and agreements
(collectively, "Claims") that I may have, or in the future may possess, with
                ------
respect to the Company Parties, including, but not limited to, any Claims
relating to my employment with the Company Parties or the termination thereof,
any Claims arising under Title VII of the Civil Rights Act of 1964, the
Rehabilitation Act of 1973, the Americans with Disabilities Act of 1990, the
Civil Rights Act of 1866, the Civil Rights Act of 1991, the Employee Retirement
Income Security Act of 1974, the Family Medical Leave Act of 1993, each of these
as amended, or any other federal or state or local law, whether such Claim
arises under statute, common law or in equity, and whether or not I or any of
the Company Parties is presently aware of the existence of such Claim, but
excluding the following Claims (the "Excluded Claims"):  (i) Claims under the
                                     ---------------
Amended and Restated Separation Agreement dated February __, 2000 between the
Company and me; (ii) Claims under the Consulting Agreement dated December 18,
1999 between the Company and me; (iii) Claims for accrued vacation pay; (iv)
Claims under the Retirement Plan for Corporate Officers of PSA, Inc. and
Participating Subsidiaries as amended and restated as of March 12, 1984; and (v)
Claims for indemnification in respect of my services as a director and/or
officer and/or employee of any of the Company Parties in accordance with
Sections 5.06(a) and (b) of the Merger Agreement and related claims under the
directors' and officers' liability insurance policy obtained in accordance with
Section 5.06(c) of the Merger Agreement.  I also hereby forever release,
discharge and waive any right I may have to recover in any proceeding brought by
any federal, state or local agency against any of the Company Parties to
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enforce any such laws, but excluding Excluded Claims. I agree that the Bonus
Payments shall be in full satisfaction of any and all Claims for payment or
other benefits of any kind that I may have against the Company Parties except
for any other Excluded Claims.

     For purposes of this letter, the "Company Parties" means the Company,
                                       ---------------
Parent and any and all of their respective predecessor or successor companies,
shareholders, subsidiaries and affiliates wherever located and each of their
present, former and future directors, officers, employees, agents, attorneys,
heirs and assigns.  Capitalized terms that are used but not defined herein have
the meanings assigned to them in the Separation Agreement.

     In addition to the foregoing, in consideration of the payment, on their
respective due dates, of each Bonus Payment, I hereby release and discharge the
Company Parties from any and all Claims (other than Excluded Claims) that I may
have as of the date I sign this letter arising under the Federal Age
Discrimination in Employment Act of 1967, as amended, and the applicable rules
and regulations promulgated thereunder (the "ADEA").  By signing this letter, I
                                             ----
hereby acknowledge and confirm the following:  (i) I was advised by the Company
to consult with an attorney of my choice prior to signing this letter and to
have such attorney explain to me the terms of this letter, including, without
limitation, the terms relating to my release of claims arising under the ADEA;
(ii) I was given a period of not fewer than 21 days to consider the terms of
this letter and to consult with an attorney of my choosing with respect thereto;
and (iii) I am providing the release and discharge set forth in this paragraph
only in exchange for consideration in addition to anything of value to which I
am already entitled.

     To ensure that the foregoing release is fully enforceable in accordance
with its terms, I agree to waive any and all rights of Section 1542 of the
California Civil Code (to the extent applicable) as it exists from time to time
or a successor provision thereto, which provides:

               A general release does not extend to claims which the creditor
     does not know or suspect to exist in his favor at the time of executing the
     release, which if known by him must have materially affected his settlement
     with the debtor.

     In addition, to ensure that the foregoing release is fully enforceable in
accordance with its terms, subject to the payment, or their respective due
dates, of each Bonus Payment, I agree to waive any protection that may exist
under any comparable or similar statute and under any principle of common law of
the United States or any and all States with respect to all Claims (other than
Excluded Claims).

     THIS MEANS THAT (EXCEPT AS EXPRESSLY PROVIDED HEREIN) BY SIGNING THIS
LETTER, I WILL HAVE WAIVED ANY RIGHT I MAY HAVE HAD TO BRING A LAWSUIT OR MAKE
ANY CLAIM AGAINST THE COMPANY

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PARTIES BASED ON ANY ACTS OR OMISSIONS OF THE COMPANY PARTIES UP TO THE DATE OF
THE SIGNING OF THIS LETTER.

     In addition I have been advised of my right to revoke this letter during
the seven-day period after signing, provided such revocation is in writing,
signed by me and delivered to the Company.  I understand that in the event of
any such revocation, all obligations of the Company with respect to the Bonus
Payments will terminate and be of no further effect as of the date of such
revocation.

                              ___________________________________
                              Johanna Unger

ACKNOWLEDGED:

PS GROUP, INC.

By:  ___________________________________
     Name:
     Title:

Date:  ___________________________________

                                       3<PAGE>

                                                                    Exhibit 10.7

                            PS GROUP HOLDINGS, INC.
                          4370 La Jolla Village Drive
                                   Suite 1050
                         San Diego, California   92122

                                February 4, 2000

Heritage Air Holdings Statutory Trust
c/o  First Union National Bank, as trustee
10 State House Square
Hartford, Connecticut   06103

Attention:  W. Jeffrey Kramer

     Re:  Agreement and Plan of Merger Dated as of December 18, 1999
          Among Ourselves, Yourselves and PSG Acquisition, Inc.
          (the "Merger Agreement")
          -----------------------------------------------------------

Gentlemen:

     In connection with the execution of the Merger Agreement, the parties had
intended the "SERP Policy" (as defined in Section 5.05(b) of the Merger
Agreement) to insure not only the obligations of PS Group, Inc. and Statex
Petroleum, Inc. specified in Section 5.05(b) but also the payments to be made by
PS Group, Inc. to Charles E. Rickershauser, Jr. under the Separation Agreement
dated December 18, 1999 between PS Group, Inc. and Mr. Rickershauser (as amended
and restated concurrently herewith, the "Rickershauser Separation Agreement").
However, Section 5.05(b) of the Merger Agreement inadvertently omitted a
provision to this effect.

     Please countersign this letter to confirm your agreement that, for all
purposes of the Merger Agreement, the SERP Policy is required to cover the
amounts due to Mr. Rickershauser, under the Rickershauser Separation Agreement,
as "Bonus Payments" (as defined in Section 2(a) thereof) together with interest
on the Bonus Payments (as specified in Section 2(b) thereof).
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     Thank you for your cooperation.

                              Very truly yours,

                              PS GROUP HOLDINGS, INC.

                              By: /s/ L. A. Guske
                                  ---------------
                                  Lawrence A. Guske
                                  Vice President-Finance
ACCEPTED AND AGREED

HERITAGE AIR HOLDINGS
STATUTORY TRUST

By:  FIRST UNION NATIONAL BANK,
     not in its individual capacity but
     solely as Trustee

     By: /s/ Brian D. Porch
        ---------------------------------
        Name:   Brian D. Porch
        Title:  Vice President, Authorized officer

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