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                                                                   EXHIBIT 10.20

                                 PROMISSORY NOTE

$552,312,000.00 (U.S.)            Houston, Texas                  March 31, 2001

     FOR VALUE RECEIVED, and intending to be legally bound, Continental Express,
Inc., a Delaware corporation ("Maker"), promises to pay to the order of
Continental Airlines, Inc. ("Holder") at its offices located at 1600 Smith,
HQSEO, Houston, Texas 77002, in lawful money of the United States of America and
in immediately available funds, FIVE HUNDRED FIFTY-TWO MILLION, THREE HUNDRED
TWELVE THOUSAND AND 00/100 DOLLARS ($552,312,000.00) together with interest on
the outstanding principal balance from day to day remaining at the annual rate
specified below and at the times specified below.

     The unpaid principal of this Note from time to time outstanding shall bear
interest from the date hereof through June 30, 2001 at a rate of 4.87625% per
annum. Beginning on the first day of the next calendar quarter, the interest
rate shall be automatically adjusted for such quarter to equal the sum of (i)
the three-month London Interbank Offer Rate as published at the close of the
second Business Day prior to the commencement of such quarter (or, if not
published on such day, the next preceding day on which it is published) on page
3750 of the Telerate Service ("LIBOR") plus (ii) 1.25 percent (1.25%); provided,
that such aggregate rate shall not exceed 3.50% in 2002, 5.35% in 2003, 6.72% in
2004 (each such maximum rate a "cap"), or in any event the Highest Lawful Rate
(as hereinafter defined). Thereafter, the interest rate shall remain equal to
LIBOR + 1.25%, but shall be automatically adjusted for each successive calendar
quarter during the term hereof based on the immediately preceding three-month
LIBOR rate as so reported, but in no event to exceed the applicable cap or the
Highest Lawful Rate. All past due principal and, to the fullest extent permitted
by applicable law, interest shall bear interest after the due date thereof at 18
percent (18%) per annum or, if lower, the Highest Lawful Rate (as hereinafter
defined). All interest accruing under this Note shall be calculated on the basis
of a 360-day year consisting of four 90-day quarters, unless such calculation
would exceed the Highest Lawful Rate, in which case interest will be calculated
on the per annum basis of a year of 365 or 366 days, as the case may be.

     From the date hereof through the second anniversary of the making of this
Note, Maker shall pay to Holder at the end of each calendar quarter, the
interest accrued through such date. Combined payments of principal and interest
shall be due and payable in quarterly installments of TWENTY-SEVEN MILLION, NINE
HUNDRED TWENTY-SEVEN THOUSAND, NINE HUNDRED AND NO/100 DOLLARS ($27,927,900.00)
commencing on March 31, 2003, or the first Business Day thereafter, and
continuing on the last Business Day of each calendar quarter thereafter. On
March 31, 2007 (or, if such date is not a Business Day, the next preceding
Business Day), the entire unpaid principal balance of this Note, if any,
together with all accrued unpaid interest, shall be due and payable in full.
"Business Day" means any day other than a Saturday or a Sunday or a day on which
banking institutions in New York, New York or Houston, Texas are authorized or
required by law or executive order to remain closed.

     Notwithstanding the foregoing, if Holder shall at any time be in default in
its payment obligations to Maker or any of its affiliates under any tax
agreement ("Tax Agreement") between Holder and Maker or one or more of Maker's
affiliates in effect from time to time, Maker shall be entitled to set off from
any payment then owing by Maker hereunder any amount so owed by Holder to Maker
or one or more of Maker's affiliates thereunder; provided that contemporaneously
with such setoff, Maker gives written notice of such action; provided further
that the failure to give such notice shall not affect the validity of the
setoff. It is specifically

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agreed that (i) for purposes of the setoff by Maker, mutuality shall be deemed
to exist among Holder, on the one hand, and Maker and any affiliate of Maker
that is party to the Tax Agreement, on the other hand; (ii) reciprocity among
Holder, Maker and any affiliate of Maker that is a party to the Tax Agreement
exists with respect to their relative rights and obligations in respect of
setoff; and (iii) the right of setoff is given as additional security to induce
the parties to enter into the transactions contemplated hereby and by the Tax
Agreement. Upon completion of such setoff, the obligation of the Holder under
the Tax Agreement and the obligation of Maker under this Note shall also be
extinguished to the extent of the amount so setoff. Holder further waives any
right to assert as a defense to any attempted setoff the requirements of
liquidation or mutuality. This setoff provision shall be without prejudice and
in addition to any right of setoff, combination of accounts, lien or other right
to which any Maker is at any time otherwise entitled (either by operation of
law, contract or otherwise).

     Maker reserves the right to prepay this Note, in whole or in part, at any
time, without penalty or notice. All prepayments made pursuant to this
paragraph, whether designated as payments of principal or interest, shall be
applied first to accrued and unpaid interest, if any, and then to principal.

     If any payment provided herein, either of principal or interest, is not
paid when due, or in the event of the dissolution, insolvency or bankruptcy of
Maker, or if any proceedings in bankruptcy or for the relief of debtors or
readjustment of debts is filed by or against Maker, or if Holder in good faith
believes the prospect of repayment of this Note is impaired or otherwise deems
itself insecure, then in any such case Holder may, at its option and at any time
thereafter, declare this Note to be forthwith due and payable, upon which this
Note shall accelerate and be immediately due and payable in full.

     Maker, to the fullest extent permitted by applicable law, hereby expressly
and severally waives grace, and all notices, demands, presentments for payment,
notice of nonpayment, protest and notice of protest, notice of intent to
accelerate, notice of acceleration of the indebtedness due hereunder, and
diligence in collecting this Note.

     To the fullest extent permitted by applicable law, if this Note is
collected by suit or legal proceedings, including bankruptcy proceedings, Maker
agrees to pay Holder hereof the reasonable costs and reasonable attorney's fees
incurred in the collection hereof.

     No failure by Holder of this Note to exercise, and no delay in exercising,
any right or remedy hereunder shall constitute a waiver thereof on the part of
Holder; nor shall any single or partial exercise of any right or remedy
hereunder preclude any other or further exercise thereof or the exercise of any
other right or remedy.

     It is the intention of the parties hereto to conform strictly to applicable
usury laws regarding the use, forbearance or detention of the indebtedness
evidenced by this Note whether such laws are now or hereafter in effect,
including the laws of the United States of America or any other jurisdiction
whose laws are applicable, and including any subsequent revisions to or judicial
interpretations of those laws, in each case to the extent they are applicable to
this Note (the "Applicable Usury Laws"). Accordingly, if any acceleration of the
maturity of this Note or any payment by Maker or any other person results in
Maker or such other person having paid any interest in excess of the Maximum
Amount, as hereinafter defined, or if any transaction contemplated hereby would
otherwise be usurious under any Applicable Usury Laws, then, in that event, it
is agreed as follows: (i) the provisions of this paragraph shall govern and
control;

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(ii) the aggregate of all interest under Applicable Usury Laws that is
contracted for, charged or received under this Note shall under no circumstances
exceed the Maximum Amount, and any excess shall be promptly refunded to Maker by
Holder hereof; (iii) neither Maker nor any other person shall be obligated to
pay the amount of such interest to the extent that it is in excess of the
Maximum Amount; and (iv) the effective rate of interest on this Note shall be
ipso facto reduced to the Highest Lawful Rate, as hereinafter defined, and the
provisions of this Note immediately shall be deemed reformed, without the
necessity of the execution of any new document or instrument, so as to comply
with all Applicable Usury Laws. All sums paid, or agreed to be paid, to Holder
hereof for the use, forbearance or detention of the indebtedness of Maker to
Holder hereof evidenced by this Note shall, to the fullest extent permitted by
the Applicable Usury Laws, be amortized, pro rated, allocated and spread
throughout the full term of the indebtedness evidenced by this Note so that the
actual rate of interest does not exceed the Highest Lawful Rate in effect at any
particular time during the full term hereof. As used herein, the term "Maximum
Amount" means the maximum nonusurious amount of interest that may be lawfully
contracted for, charged or received by Holder hereof in connection with the
indebtedness evidenced by this Note under all Applicable Usury Laws, and the
term "Highest Lawful Rate" means the maximum rate of interest, if any, that may
be charged Maker under all Applicable Usury Laws on the principal balance of
this Note from time to time outstanding.

     THIS NOTE SHALL BE SUBJECT TO AND CONSTRUED AND ENFORCED IN ACCORDANCE WITH
THE INTERNAL LAWS OF THE STATE OF DELAWARE WITHOUT GIVING EFFECT TO ANY
CONFLICTS OF LAWS PRINCIPLES.

     IN WITNESS WHEREOF, the undersigned has caused this Note to be executed at
the place and as of the date first above appearing.

                                       CONTINENTAL EXPRESS, INC.

                                       By:
                                           -------------------------------------
                                           James B. Ream
                                           President

ATTEST:

By:
    -------------------------------
    Scott R. Peterson
    Assistant Secretary

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                                                                   EXHIBIT 10.21

                           MEMORANDUM OF UNDERSTANDING

     This Memorandum of Understanding, by and among Continental Airlines, Inc.,
a Delaware corporation ("Continental"), ExpressJet Holdings, Inc., a Delaware
corporation ("Holdings"), and ExpressJet Airlines, Inc., a Delaware corporation
and a wholly owned subsidiary of Holdings ("ExpressJet" and, collectively with
Holdings, "Contractor"), is dated as of December 31, 2001.

     The parties comprise all of the parties to that certain Capacity Purchase
Agreement (the "CPA"), dated as of January 1, 2001, pursuant to which Contractor
has agreed to provide certain Regional Airline Services to Continental, and
Continental has agreed to purchase from Contractor the capacity of Contractor's
regional aircraft, each in accordance with the terms and conditions set forth in
the CPA. Upper-case terms not otherwise defined herein have the meanings
ascribed to them in the CPA.

     Section B.11 of Schedule 3 to the CPA provides in relevant part as follows:
"If there is a material change in the parties' underlying assumptions regarding
the cost of providing Regional Airline Services, the parties hereto shall meet
and confer to discuss such change and whether the Base Compensation, the
Appendix 1 Expenses or any of the provisions of this Schedule 3 shall be
adjusted... ." Pursuant to said Section B.11, the parties have met to confer and
discuss the impact of the terrorist attacks of September 11, 2001 and the
resulting impact on the airline industry in the wake of those attacks. In so
doing, the parties have determined that the effects of the terrorist attacks,
including the temporary grounding of all non-military aviation in the United
States, sharply declining passenger and cargo traffic, sharply declining yields
and revenue, the temporary or possibly permanent grounding of aircraft,
including Covered Aircraft, constitute a material change in their underlying
assumptions regarding the cost of providing Regional Airline Services.

     The parties have determined that an appropriate reconciliation be made for
the material changes described above by reducing the compensation otherwise
required to be paid by Continental to Contractor under Article III of the CPA
for the period September 11-December 31, 2001 by $32,639,000.

     In consideration for Contractor's agreement to reduce the compensation
otherwise payable to it in the manner described above, Continental agrees to (i)
extend to March 31, 2007 the term of that certain promissory note dated March
31, 2001 in the original principal amount of $552,312,000.00 made by ExpressJet
in favor of Continental, (ii) cap the interest rate otherwise payable under such
promissory note through 2004 and otherwise modify the note as agreed by the
parties and (iii) amend Section 6.02(b) of the CPA to read "December 31, 2005"
in lieu of "December 31, 2004."

     The parties agree that this Memorandum of Understanding shall be binding
upon each of them and shall be enforceable in accordance with the terms of the
CPA as though it formed a part thereof.

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     IN WITNESS WHEREOF, the parties hereto have caused this Memorandum of
Understanding to be duly executed and delivered as of the date and year first
written above.

                                CONTINENTAL AIRLINES, INC.

                                By:
                                    -------------------------------------------
                                    Gerald Laderman
                                    Senior Vice President-Finance and Treasurer

                                EXPRESSJET HOLDINGS, INC.

                                By:
                                    -------------------------------------------
                                    Frederick S. Cromer
                                    Vice President and Chief Financial Officer

                                EXPRESSJET AIRLINES, INC.

                                By:
                                    -------------------------------------------
                                    Frederick S. Cromer
                                    Vice President and Chief Financial Officer

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