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                              MESA AIR GROUP, INC.                     Exhibit 4
                      1999 NON-QUALIFIED STOCK OPTION PLAN


                  1. Purpose of Plan. The Purpose of this Plan is to advance the
interest of Mesa Air Group, Inc., a Nevada corporation (hereinafter called the
"Company") and its shareholders by providing a means whereby employees of the
Company, or any subsidiary thereof, may be given an opportunity to purchase
Common Stock (hereinafter called "shares") of the Company under options granted
under the Plan, to the end that the Company may retain present personnel upon
whose judgment, initiative and efforts the successful conduct of the business of
the Company largely depends, and may attract new personnel. Further, this Plan
has been adopted to facilitate the assumption of the outstanding options of
CCAIR, Inc. ("CCAIR") that were assumed (the "Assumed Options") by the Company
in connection with the merger (the "Merger") of Mesa Merger Corporation with
and into CCAIR.

                  2. Shares Subject to the Plan. The aggregate number of shares
of the Company for which options may be granted under this Plan shall be
189,527, which shares representing the number of shares of common stock of CCAIR
underlying the Assumed Options, as adjusted for the exchange ratio in the
Merger; provided, however, that whatever number of shares shall remain reserved
for issuance pursuant to the Plan at the time of any stock split, stock dividend
or other change in the Company's capitalization shall be appropriately and
proportionately adjusted to reflect such stock dividend, stock split or other
change in capitalization. Such shares shall be made available from authorized
but unissued or reacquired shares of the Company. Any shares for which an option
is granted hereunder that are released from such option for any reason shall
become available for other options to be granted under this Plan.

                  3. Administration of the Plan. This Plan shall be administered
under the supervision of the Board of Directors. Subject to the express
provisions of this Plan, the Board shall have conclusive authority to construe
and interpret the Plan, any stock option agreement entered into thereunder, and
any stock appreciation right granted thereunder and to establish, amend, and
rescind rules and regulations for its administration.

                  4. Granting of Options. The Board from time to time shall
designate from among the full-time key employees of the Company those employees
to whom stock options to purchase shares shall be granted under this Plan, the
number of shares which shall be subject to each option so granted, and the type
of option granted. The Board shall direct an appropriate officer of the
Corporation to execute and deliver option agreements to employees reflecting the
grant of options.
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                  5. Option Period. No stock option granted under this Plan may
be exercised later than ten years from the date of grant.

                  6. Option Price. The option price shall be fixed by the Board
and set forth in the Option Agreement, which price shall not be less than the
per share fair market value of the outstanding shares of the Company on the date
that the option is granted, as determined by the Board. The Board may fix such
option price and authorize one or more officers of the Company to compute the
price. The option price may be payable in cash, Company stock, or a combination
thereof. The date on which the Board approves the granting of an option shall be
deemed the date on which the option is granted.

                  7. Option Agreement. The Option Agreement in which option
rights are granted to an employee shall be in the applicable form (consistent
with this Plan) from time to time approved by the Board and shall be signed on
behalf of the Company by the Chairman of the Board, the President, any Vice
President or the Secretary of the Company other than the employee who is a party
thereto, and shall be dated as of the date of the granting of the option, as
determined in Paragraph 6 hereof.

                  8. Amendment and Termination of the Plan. The Company, by
action of its Board of Directors, reserves the right to amend, modify or
terminate at any time this Plan, or, by action of the Board with the consent of
the optionee, to amend, modify or terminate any outstanding option agreement or
grant of stock appreciation rights, except that the Company may not, without
further shareholder approval, increase the total number of shares as to which
options may be granted under the Plan (except increases attributable to the
adjustments authorized in Paragraph 2 hereof), change the employees or class of
employees eligible to receive options or materially increase the benefits
accruing to participants under the Plan. Moreover, no action may be taken by the
Company (without the consent of the optionee) which will impair the validity of
any option then outstanding.

                  9. Effective Date of Plan. The Plan shall be effective upon
adoption of the Plan by the Board of Directors of the Company.


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                  10. Expiration of Plan. Options may be granted under this Plan
at any time prior to June 8, 2009, on which date the Plan shall expire but
without affecting any options then outstanding.


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