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                                                                       Exhibit 4

                              MESA AIR GROUP, INC.

                              RESTATED AND AMENDED
                           EMPLOYEE STOCK OPTION PLAN

RECITALS:

         A. On December 1, 1995, the Board of Directors of Mesa Air Group, Inc.
(the "Company") adopted an Employee Stock Option Plan to be effective as of June
28, 1995 (the "Employee Plan").

         B. On March 22, 1996, the Board of Directors of the Company adopted the
First Amendment to the Employee Plan and thereafter, on April 8, 1996, the
Employee Plan, as amended, was approved by the shareholders of the Company.

         C. The Employee Plan, as amended, provides that amendments to the
Employee Plan may be adopted without the approval of shareholders so long as the
amendments are not Material Amendments as defined in Section 4(b) of the
Employee Plan, as amended.

         D. The Company desires to further amend the Employee Plan, as amended,
to correct certain typographical and reference errors and to conform the
Employee Plan to the existing policy of the Company which restricts trading in
securities of the Company by certain employees and, in doing so to restate the
Plan as amended. The Employee Plan as amended and restated is hereinafter
referred to as the "Plan."

1.       PURPOSE OF THE PLAN; TYPE OF PLAN

         (a) Attract and Retain Key Employees. The purpose of the Plan is to
attract and retain key employees who are and will be responsible for the growth
and success of the Company and its subsidiaries. The term "subsidiary" means any
corporation other than the Company in an unbroken chain of corporations
beginning with the Company if, at the time of the granting of the Option, as
defined below, each of the corporations other than the last corporation in the
unbroken chain owns shares possessing 50% or more of the total combined voting
power of all classes of stock in one of the other corporations in such chain.
The term "Employee" includes individuals employed by the Company or any of its
subsidiaries.

         (b) Incentive Stock Options. Some one or more of the options ranted
under the Plan may be intended to qualify as an "incentive stock option" as
defined in Section 422 of the Internal Revenue Code of 1986, as amended (the
"Code"), and any grant of such an option shall clearly specify that such option
is intended to so qualify. If no such specification is made, an option granted
hereunder shall be intended to not qualify as an "incentive stock option."

         (c) Exemption from Short-Swing Liability. Options granted to Officers
or Directors of the Company ("Insiders") pursuant to this Plan shall be exempt
from Section 16(b) of the



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Securities Exchange Act of 1934, as amended (the "Exchange Act"), pursuant to
Regulation Section 240.16(b)-3 adopted under the Exchange Act which was enacted
on May 1, 1991.

         (d) Formula Plan. This Plan may be administered by the Board of
Directors of the Company (the "Board") or by any person or persons chosen by a
majority of the Board. Grants or awards made pursuant to this Plan are to be
made pursuant to the formula set forth in Section 3 (the "Formula") which may be
adjusted for non-Insiders at the sole discretion of the Compensation Committee
upon the recommendation of the Chief Executive Officer. The Formula is intended
to qualify under Regulation 240.16b-3(c)(2)(ii) of the Exchange Act, thereby
alleviating the necessity for disinterested administration of the Plan required
by Regulation 240.16b-3(c)(2)(i).

2.       STOCK AND MAXIMUM NUMBER OF SHARES SUBJECT TO PLAN

         (a) Description of Stock and Maximum Shares Allocated. The stock
subject to the provisions of this Plan and issuable upon exercise of the Options
are shares of the Company's Common Stock, no par value, which may be either
unissued or treasury shares, as the Board may from time to time determine.
Subject to adjustment as provided in Section 6, the aggregate number of shares
of Common Stock covered by the Plan issuable upon exercise of all Options shall
be 2,800,000 Shares, which shares shall be reserved for use upon the exercise of
the Options. The shares available for Options and all other shares of Common
Stock of the Company shall be referred to as the "Shares."

         (b) Restoration of Unpurchased Shares. If an Option expires or
terminates for any reason prior to the exercise in full before the term of the
Plan expires, the Shares subject to, but not issued under, such Option shall
again be available for other Options hereafter granted.

3.       FORMULA AND OPERATION OF THE PLAN

         (a) Eligible Persons. Options shall automatically be granted to the
Insiders listed on Schedule "A" in the amounts provided in Section 3(b) and on
Schedule "B." Unless otherwise directed by the Chief Executive Officer, Options
shall be granted to the persons, other than Insiders, who fill each of the
positions listed on Schedule "C" attached hereto (all parties listed on Schedule
"C" shall be referred to herein as "Key Employees").

         (b)      Date of Grants; Allotment; Adjustment.

         Options shall be granted to Insiders in the amounts set forth in
Schedule "B" on June 28, 1995 and on April 1, 1996 and 1997; and, with respect
to non-Insiders, on those same dates in amounts determined by the Chief
Executive

         Officer of the Company up to a maximum amount of 370,000 Options per
year. If an Insider is employed by the Company after June 28, 1995, Insider
shall, upon the first day of employment, be granted a pro rata portion of the
Options as set forth in the column labeled "April 1, 1996 and 1997" shown on
Schedule "B" (collectively, the "Pro Rata Options") and Options shall be granted
to such Insider on each succeeding April 1 in the amounts set forth in


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Schedule "B." The amount of Pro Rata Options to be granted to each Insider shall
be calculated by dividing the number of days prior to April 1 by the number of
days in the calendar year and multiplying the quotient by the number of Options
listed in Schedule "B" to be allotted to that Insider. Options granted to
non-Insider Key Employees employed by the Company subsequent to June 28, 1995,
shall be pro-rated in a similar manner if granted for the year in which
employment commenced.

         (c) Price. The Option price per Share shall not be less than the fair
market value of the Shares, as defined below, on the Grant Date.

         (d)      Fair Market Value.

                  (1) If the options granted are intended to qualify as
         incentive stock options, the fair market value of a Share on any
         particular day shall be determined as follows:

                           (a) If the Shares are listed or admitted to trading
                  on any securities exchange, the fair market value shall be the
                  average sales price on such day on the New York Stock
                  Exchange, or if the Shares have not been listed or admitted to
                  trading on the New York Stock Exchange, on such other
                  securities exchange on which such stock is then listed or
                  admitted to trading, or if no sale takes place on such day on
                  any such exchange, the average of the closing bid and asked
                  price on such day as officially quoted on any such exchange;

                           (b) If the Shares are not then listed or admitted to
                  trading on any securities exchange, the fair market value
                  shall be the average sales price on such day or, if no sale
                  takes place on such day, the average of the reported closing
                  bid and asked price on such date, in the over-the-counter
                  market as furnished by the National Association of Securities
                  Dealers Automated Quotation ("NASDAQ"), or if NASDAQ at the
                  time is not engaged in the business of reporting such prices,
                  as furnished by any similar firm then engaged in such business
                  and selected by the Board; or

                           (c) If the Shares are not then listed or admitted to
                  trading in the over-the-counter market, the fair market value
                  shall be the amount determined by the Board in a manner
                  consistent with Treasury Regulation

         Section 20-2031-2 promulgated under the Code or in such other manner
prescribed by the Secretary of the Treasury or the Internal Revenue Service.

                  (2) If the Options granted are not intended to qualify as
         incentive stock options, the fair market value of a Share on any
         particular day shall be determined as follows:

                           (a) If the Shares are listed or admitted to trading
                  on any securities exchange, the fair market value shall be the
                  low sales price on such day on the New York Stock Exchange, or
                  if the Shares have not been listed or admitted to


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                  trading on the New York Stock Exchange, on such other
                  securities exchange on which such stock is then listed or
                  admitted to trading, or if no sale takes place on such day on
                  any such exchange, the average of the closing bid and asked
                  price on such day as officially quoted on any such exchange;

                           (b) If the Shares are not then listed or admitted to
                  trading on any securities exchange, the fair market value
                  shall be the low sales price on such day or, if no sale takes
                  place on such day, the low closing bid price on such date, in
                  the over-the-counter market as furnished by the National
                  Association of Securities Dealers Automated Quotation
                  ("NASDAQ"), or if NASDAQ at the time is not engaged in the
                  business of reporting such prices, as furnished by any similar
                  firm then engaged in such business and selected by the Board;
                  or

                           (c) If the Shares are not then listed or admitted to
                  trading in the over-the-counter market, the fair market value
                  shall be the amount determined by the Board in a manner
                  consistent with Treasury Regulation Section 20-2031-2
                  promulgated under the Code or in such other manner prescribed
                  by the Secretary of the Treasury or the Internal Revenue
                  Service.

                           (e) Duration of Plan. The term of the Plan, unless
                  previously terminated by the Board, is ten years or June 28,
                  2005. No Option shall be granted under the Plan unless granted
                  within ten years after the adoption of the Plan by the Board,
                  but Options outstanding on that date shall not be terminated
                  or otherwise affected by virtue of the Plan's expiration.

                           (f) Vesting of the Options and Pro Rata Options.
                  One-third of the total Options granted on a Grant Date shall
                  vest on the first anniversary date after the Grant Date;
                  one-third of the total Options granted on a Grant Date shall
                  vest on the second anniversary date after the Grant Date; and
                  the remaining one-third of the total Options granted on a
                  Grant Date shall vest on the third anniversary date after the
                  Grant Date. One-third of the total Pro Rata Options shall vest
                  on the first April 1 after their Grant Date (the "Initial
                  Vesting Date"); one-third of the total Pro Rata Options shall
                  vest on the first anniversary date after the Initial Vesting
                  Date; and the remaining one-third of the total Pro Rata
                  Options shall vest on the second anniversary date after the
                  Initial Vesting Date. However, Pro Rata Options granted to
                  Insiders on or after October 1 and prior to April 1 in any
                  year shall not vest until the second April 1 following the
                  Grant Date at which time two-thirds of the total Pro Rata
                  Options shall vest and the remaining one-third of the total
                  Pro Rata Options shall vest on the first anniversary date
                  thereafter.

NOTWITHSTANDING ANY PROVISION HEREIN TO THE CONTRARY, OPTIONS GRANTED TO THE KEY
EMPLOYEES SHALL NOT BECOME EXERCISABLE UNTIL SHAREHOLDER APPROVAL AS REQUIRED BY
SECTION 4(a) OF THE PLAN HAS BEEN OBTAINED; AND OPTIONS GRANTED TO INSIDERS
SHALL NOT BECOME EXERCISABLE UNTIL (i) A MINIMUM OF SIX (6) MONTHS HAS PASSED
FROM THE


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DATE OF SHAREHOLDER APPROVAL, OR (ii) A MINIMUM OF ONE (1) YEAR HAS PASSED FROM
THE GRANT DATE, WHICHEVER OCCURS LATER.

4.       TERMS AND CONDITIONS OF OPTIONS

         (a) Approval by Shareholders. The Plan shall be submitted to the
shareholders of the Company for their approval at their regular meeting to be
held within twelve (12) months after the adoption of the Plan by the Board.
Shareholder approval shall be evidenced by the affirmative vote of the holders
of a majority of the Shares of Common Stock present in person or by proxy and
voting at the meeting. If the shareholders decline to approve the Plan at such
meeting or if the Plan is not approved by the shareholders within twelve (12)
months after its adoption by the Board, the Plan and all Options and rights
granted hereunder shall automatically terminate to the same extent and with the
same effect as though the Plan had never been adopted.

         (b) Amendments to Plan. The approval of the shareholders of the Company
shall be required to (i) increase the aggregate number of shares of Common Stock
subject to the Plan; (ii) change the class of persons eligible to receive
Options; (iii) modify the period within which Options may be granted, the
exercise price or the terms upon which Options may be exercised; (iv) change the
exercise price of the Options except as provided in Section 6; or (v) increase
the material benefits accruing to participants under the Plan. (Collectively,
each of these changes in the Plan are referred to herein as "Material
Amendments.") Notwithstanding any other terms contained herein to the contrary,
no Material Amendments shall be made to the Plan more than one time in any given
one year period. The Board, however, may suspend or terminate the Plan at any
time.

         (c) Individual Agreements. Options granted under the Plan shall be
evidenced by agreements in such form as the Board from time to time approves,
which agreements shall substantially comply with and be subject to the terms of
the Plan.

         (d) Required Provisions. Each agreement shall state (i) the total
number of shares to which it pertains, (ii) the exercise price for the shares
covered by the option, (iii) the time at which the option becomes exercisable,
(iv) the scheduled expiration date of the option, (v) the vesting period(s) for
such options, and (vi) the timing and conditions of issuance of any stock option
exercise.

         (e) No Fractional Shares. Options shall be granted and exercisable only
for whole shares; no fractional shares will be issuable upon exercise of any
Option granted under the Plan. Fractional Options shall be rounded down to the
nearest whole share number.

         (f) Method of Exercising Options. Options shall be exercised by written
notice to the Company, addressed to the Company at its principal place of
business. Such notice shall state the election to exercise the option and the
number of shares with respect to which it is being exercised, and shall be
signed by the person exercising the option. Such notice shall be accompanied by
payment in full of the exercise price for the number of Shares being purchased.
Payment may be made in cash or by bank cashier's check or by tendering duly
endorsed certificates for shares of the Company's Common Stock then owned by the
optionholder. The


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Company shall deliver a certificate or certificates representing the Option
Shares to the purchaser as soon as practicable after payment for those Shares
has been received. If an Option is exercised by any person other than the
optionholder, such notice shall be accompanied by appropriate proof of the right
of such person to exercise the Option. All Shares that are purchased and paid
for in full upon the exercise of an Option shall be fully paid and
non-assessable. The Board may determine that payment upon the exercise of an
Option may be made with Shares owned by the Key Employee having a fair market
value on the exercise date equivalent to the amount of payment, or any
combination of cash and such Shares equal to such amount.

         (g) No Rights of a Shareholder. An optionholder shall have no rights as
a shareholder with respect to shares covered by an Option. No adjustment will be
made for cash dividends for which the record date is prior to the date a stock
certificate is issued upon exercise of an Option. Upon such exercise of an
Option, the holder of the Shares of Common Stock so received shall have all the
rights of a shareholder of the Company as of the date of issuance.

5.       TERMINATION OF EMPLOYMENT; ASSIGNABILITY; DEATH

         (a) Termination of Employment. If any optionholder ceases to be an
employee of the Company other than for Retirement (as such is defined in Section
5(b)), death, disability or discharge for cause, such holder (or his successors
in the case of the holder's death after the termination of employment) may,
within three months after the date of termination, but in no event after the
stated expiration date, purchase some or all of the Shares with respect to which
such optionholder was entitled to exercise such Option on the date employment
terminated; provided, that if after employment is terminated, the holder commits
acts detrimental to the Company's interests, then the Option shall thereafter be
void for all purposes.

         (b) Retirement. If any optionholder (i) ceases to be an employee of the
         Company other than by reason of death, disability or discharge for
         cause; and (ii) has been continuously employed by the Company for five
         or more years; and is (iii) over fifty-nine and one-half (59-1/2) years
         of age (collectively referred to as "Retirement"), all of the options
         which have been granted to such optionholder prior to Retirement shall
         vest thirty (30) days after Retirement (the "Vested Options"). Such
         holder (or his successors in the case of the holders death after
         Retirement) may, within three months after the date of Retirement or
         prior to the stated expiration date, whichever first occurs, purchase
         some or all of the Shares which such optionholder was entitled to
         exercise; provided, that (i) if the holder's employment is terminated
         for dishonesty or other acts detrimental to the Company's interests or
         for the holder's breach of any employment, confidentiality or other
         contract or agreement with the Company, or (ii) if after employment is
         terminated, the holder commits acts detrimental to the Company's
         interests, then the Option shall thereafter be void for all purposes.

         (c) Assignability. No Option or the privileges conferred thereby shall
be assignable or transferable by a holder other than by will or the laws of
descent and distribution.

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         (d) Disability. If the optionholder is removed as an employee due to
disability, the optionholder may exercise the Options, in whole or in part, to
the extent they were exercisable on the date when the optionholder's employment
terminated, at any time prior to the expiration date of the Options or within
one year of the date of removal, whichever is earlier.

         (e) Discharge for Cause. If an optionholder is removed as an employee
of the Company for cause, the Options shall terminate upon receipt by the
optionholder of a notice of such removal or on the effective date of the
removal, whichever is earlier. The Board shall have the right to determine
whether the optionholder has been discharged for cause for purposes of the Plan
and the date of such discharge.

         (f) Death of Holder. If optionholder dies while serving as an employee,
an Option shall be exercisable until the stated expiration date thereof by the
person or persons ("successors") to whom the holder's rights pass under will or
by the laws of descent and distribution, but only to the extent that the holder
was entitled to exercise the Option at the date of death. An Option may be
exercised (and payment of the option price made in full) by the successors only
after written notice to the Company, specifying the number of shares to be
purchased. Such notice shall comply with the provisions of Section 4(e).

6.       CERTAIN ADJUSTMENTS

         (a) Capital Adjustments. Except as limited by Section 422 of the Code,
the aggregate number of Shares subject to the Plan, the number of Shares covered
by outstanding Options, and the price per share stated in such Options shall be
proportionately adjusted for any increase or decrease in the number of
outstanding Shares of Common Stock of the Company resulting from a subdivision
or consolidation of shares or any other capital adjustment or the payment of a
stock dividend or any other increase or decrease in the number of such shares
effected without receipt by the Company of consideration therefor in money,
services or property.

         (b) Mergers, Etc. Except as limited by the provisions of Section 422 of
the Code, if the Company is the surviving corporation in any merger or
consolidation, any Option granted under the Plan shall pertain to and apply to
the securities to which a holder of the number of Shares subject to the Option
would have been entitled. A dissolution or liquidation of the Company shall
cause every Option outstanding hereunder to terminate, unless specifically
provided otherwise by the Board. A merger or consolidation in which the Company
is not the surviving corporation shall also cause every Option outstanding
hereunder to terminate, unless specifically provided otherwise by the Board, but
each holder shall have the right immediately prior to a merger or consolidation
in which the Company is not the surviving corporation, to exercise such Option
in whole or in part without regard to whether such Options have vested.

7.       COMPLIANCE WITH LEGAL REQUIREMENTS

         (a) For Investment Only. If, at the time of exercise of this option,
there is not in effect as to the Option Shares being purchased a registration
statement under the Securities Act of 1933, as amended (or any successor
statute) (collectively the "1933 Act"), then the exercise of this option shall
be effective only upon receipt by the Company from the Key Employee (or his


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legal representatives or heirs) of a written representation that the Option
Shares are being purchased for investment and not for distribution.

         (b) Registration Statement Preparation. The Key Employee hereby agrees
to supply the Company with such information and to cooperate with the Company,
as the Company may reasonably request, in connection with the preparation and
filing of the registration statements and amendments thereto under the
Securities Act of 1933 and applicable state statutes and regulations applicable
to the Option Shares. The Company shall not be liable for failure to issue any
such Option Shares where such opinion of counsel cannot be obtained within the
period specified for the exercise of the option, or where such registration is
required in the opinion of counsel. If shares of Common Stock of the Company
are, at the time of the exercise of this option, listed upon a securities
exchange, the exercise of this option shall be contingent upon completion of the
necessary steps to list the Option Shares being purchased upon such securities
exchange.

         (c) Additional Restrictions on Option Exercise. Key Employee may only
exercise Options during the period commencing three days following the release
for publication of quarterly or annual financial information regarding the
Company and ending two weeks prior to the end of the then current fiscal quarter
of the Company (the "Release Period").

         A "release for publication" shall be deemed to be satisfied if the
specified financial data appears:

                  (1)      On a wire service;

                  (2)      A financial news service;

                  (3)      In a newspaper of general circulation; or

                  (4)      Is otherwise made publicly available.

         Notwithstanding any provision to the contrary contained herein, a Key
Employee may exercise Options only so long as such exercise does not violate the
law or any rule or regulation adopted by the appropriate governmental authority.

8.       MISCELLANEOUS

         (a) No Funding. This Plan shall be unfunded. The Company shall not be
required to establish any special or separate fund or to make any other
segregation of assets to assure any payment under the Plan.

         (b) New Mexico Law. The Plan and the Options shall be governed by the
laws of the State of New Mexico.

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         (c) Modification of Grant, Vesting Date. Should April 1 in any given
year fall on a day on which trading in the Shares is closed, the action which
would have taken place on April 1 shall be delayed until the first day after
April 1 that trading in the Shares commences.

         (d) Withholding of Taxes. The Company shall have the right to deduct
from any other compensation of the Grantee any federal, state or local income
taxes (including FICA) required by law to be withheld with respect to the
granting or exercise of any Options.

DATED as of the 23rd day of April, 1996 and effective as of June 28, 1995.

                                         MESA AIR GROUP, INC.


                                         By: ____________________________
                                              W. Stephen Jackson
                                              Chief Financial Officer

ATTESTED BY:


By:__________________

_____________________, Secretary





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                         FIRST AMENDMENT TO RESTATED AND
                          AMENDED MESA AIR GROUP, INC.
                           EMPLOYEE STOCK OPTION PLAN


         This FIRST AMENDMENT TO RESTATED AND AMENDED MESA AIR GROUP, INC.
EMPLOYEE STOCK OPTION PLAN (the "Amendment") is dated as of the effective date
set forth below, by Mesa Air Group, Inc. (the "Company").

                                    RECITALS:

         A. The Board of Directors of the Company adopted a Restated and Amended
Employee Stock Option Plan to be effective as of June 28, 1995 (the "Employee
Plan") and thereafter, on April 8, 1996, the Employee Plan was approved by the
shareholders of the Company.

         B. The Company believes that the annual issuance of stock options is an
important factor in attracting, motivating and retaining qualified key employees
essential to the success of the Company.

         C. As of April 1, 1998, there were approximately 345,000 options
available for grant pursuant to the Employee Plan.

         D. The Company desires to increase the aggregate number of options
available for issuance pursuant to the Employee Plan and to permit the granting
of options to future senior officers not listed in the allocation table.

         E. The Company desires to amend the Employee Plan to reflect changes in
the law under which the Employee Plan is governed.

         F. The Company has entered into employment agreements with the Chief
Executive Officer and the Chief Financial Officer that necessitate amending the
Employee Plan.

         G. The Company desires to change the law governing the Employee Plan to
reflect the change in the Company's domicile in 1996.

         H. On June 1, 1998, the Board of Directors adopted this First Amendment
to the Employee Plan subject to approval by the shareholders of the Company.

         THEREFORE, the Employee Plan is hereby amended as follows:

         1. Section 1(d) Formula Plan is hereby deleted in its entirety. The
following language is substituted in its place:

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                  Formula Plan. This Plan may be administered by the Board of
                  Directors of the Company (the "Board"), the Compensation
                  Committee or by any person or persons chosen by a majority of
                  the Board. Grants or awards made pursuant to this Plan are to
                  be made pursuant to the formula set forth in Section 3 (the
                  "Formula") which may be adjusted for non-Insiders at the sole
                  discretion of the Compensation Committee upon the
                  recommendation of the Chief Executive Officer.

         2. Section 2(a) Description of Stock and Maximum Shares Allocated is
hereby deleted in its entirety. The following language is substituted in its
place:

                  The stock subject to the provisions of this Plan and issuable
                  upon exercise of the Options are shares of the Company's
                  Common Stock, no par value, which may be either unissued or
                  treasury shares, as the Board may from time to time determine.
                  Subject to adjustment as provided in Section 6, the aggregate
                  number of shares of Common Stock covered by the Plan issuable
                  upon exercise of all Options shall be four million three
                  hundred thousand (4,300,000) Shares, which shares shall be
                  reserved for use upon the exercise of the Options. The shares
                  available for Options and all other shares of Common Stock of
                  the Company shall be referred to as the "Shares."

         3. Section 3(a) Eligible Persons is hereby deleted in its entirety. The
following language is substituted in its place:

                           (a) Eligible Persons. Options shall automatically be
                  granted to the Insiders listed on Schedule "A" in the amounts
                  provided in Section 3(b) and on Schedule "B." Unless otherwise
                  directed by the Chief Executive Officer, Options shall be
                  granted to the persons, other than Insiders, who fill each of
                  the positions listed on Schedule "C" attached hereto (all
                  parties listed on Schedule "C" shall be referred to herein as
                  "Key Employees").

         Notwithstanding Section 3(a) above, the Compensation Committee, upon
the recommendation of the Chief Executive Officer, may grant Options to officers
other than those with positions listed on Schedule "A" or reduce the annual
allocation of options to officers listed in Schedule "B" who are employed by the
Company after August 1, 1998.

         4. Section 3(b) Date of Grants; Allotment; Adjustment is hereby deleted
in its entirety. The following language is substituted in its place:

                  Options shall be granted to Insiders in the amounts set forth
                  in Schedule "B" on April 1, 1998, 1999 and 2000; and, with
                  respect to non-Insiders, on those same dates in amounts
                  determined by the


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                  Chief Executive Officer of the Company. If an Insider is
                  employed by the Company after April 1, 1998, Insider shall,
                  upon the first day of employment, be granted a pro rata
                  portion of the Options as set forth in the column labeled
                  "April 1, 1999 and 2000" shown on Schedule "B" (collectively,
                  the "Pro Rata Options") and Options shall be granted to such
                  Insider on each succeeding April 1 in the amounts set forth in
                  Schedule "B." The amount of Pro Rata Options to be granted to
                  each Insider shall be calculated by dividing the number of
                  days prior to April 1 by the number of days in the calendar
                  year and multiplying the quotient by the number of Options
                  listed in Schedule "B" to be allotted to that Insider.

         5. Section 4(b) Amendments to Plan is hereby deleted in its entirety.
The following language is substituted in its place:


                           (b) Amendments to Plan. The approval of the
                  shareholders of the Company shall be required to (i) increase
                  the aggregate number of shares of Common Stock subject to the
                  Plan; (ii) modify the period within which Options may be
                  granted, the exercise price or the terms upon which Options
                  may be exercised if such terms or changes would be materially
                  beneficial to the Optionholder; (iii) change the exercise
                  price of the Options except as provided in Section 6; or (iv)
                  increase the material benefits accruing to participants under
                  the Plan. (Collectively, each of these changes in the Plan are
                  referred to herein as "Material Amendments.") The Board may
                  suspend or terminate the Plan at any time.


         6. Section 5(a) Termination of Employment is hereby deleted in its
entirety. The following language is substituted in its place:

                           (a) Termination of Employment. If any optionholder
                  ceases to be an Employee of the Company other than for
                  Retirement (as such is defined in Section 5(b)), death,
                  disability, termination by the Company "Without Good Cause"
                  (with respect to Employees subject to employment agreements
                  with the Company), termination by the Employee for "Good
                  Reason" (with respect to Employees subject to employment
                  agreements with the Company) or discharge for cause, such
                  holder (or his successors in the case of the holder's death
                  after the termination of employment) may, within three (3)
                  months after the date of termination, but in no event after
                  the stated expiration date, purchase some or all of


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                  the Shares with respect to which such optionholder was
                  entitled to exercise such Option on the date employment
                  terminated.

         7. Section 5(b) Retirement is hereby deleted in its entirety. The
following language is substituted in its place:

                           (b) Retirement. If any optionholder (i) ceases to be
                  an employee of the Company other than by reason of death,
                  disability or discharge for cause; and (ii) has been
                  continuously employed by the Company for five or more years;
                  and is (iii) over fifty-nine and one-half (59-1/2) years of
                  age (collectively referred to as "Retirement"), all of the
                  options which have been granted to such optionholder prior to
                  Retirement shall vest thirty (30) days after Retirement (the
                  "Vested Options"). Such holder (or his successors in the case
                  of the holder's death after Retirement) may, within three
                  months after the date of Retirement or prior to the stated
                  expiration date, whichever first occurs, purchase some or all
                  of the Shares which such optionholder was entitled to
                  exercise; provided, that if after employment is terminated,
                  the holder commits acts detrimental to the Company's
                  interests, then the Option shall thereafter be void for all
                  purposes.

         8. Section 5 TERMINATION OF EMPLOYMENT; ASSIGNABILITY; DEATH shall be
amended to include the following language:

                           (g) Termination of Key Employee. Notwithstanding any
                  language contained in Section 5(a), upon the termination of
                  any Key Employee (with whom the Company has entered into an
                  Employment Agreement) for Good Reason by the Key Employee or
                  Without Cause by the Company, as those terms are defined in
                  such Employment Agreement, all Options granted on or prior to
                  the date of termination shall immediately vest and any risk of
                  forfeiture with respect thereto shall be deemed to have
                  lapsed.

         9. Section 8(b) New Mexico Law is hereby deleted in its entirety. The
following language is substituted in its place:

                           (b) Nevada Law. The Plan and the Options shall be
                  governed by the laws of the State of Nevada.

         10. Schedule A is hereby deleted in its entirety. The following
language is substituted in its place:

                  Jonathan G. Ornstein, Chief Executive Officer J. Clark
                  Stevens, Chief Operating Officer Blaine M. Jones, Chief
                  Financial Officer Gary E. Risley, Chief Legal Officer

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<PAGE>   14

         11. Schedule B is hereby deleted in its entirety. The following
language is substituted in its place:


<TABLE>
<CAPTION>

   POSITION                       APRIL 1, 1998 OPTION    APRIL 1, 1999 AND 2000
                                        AMOUNTS              OPTION AMOUNTS
<S>                               <C>                     <C>
MESA AIR GROUP, INC.:

Chief Executive Officer                        0                        0

Chief Operating Officer                   80,000                   80,000

Chief Financial Officer                   50,000(1)                     0

Chief Legal Officer                       50,000                   50,000
</TABLE>


(1)      Granted to W. Stephen Jackson before his resignation.

         DATED as of the 1st day of June, 1998 and effective as of April 1,
1998, except with respect to Section 5(g) which shall not be effective until
August 1, 1998.

                                           MESA AIR GROUP, INC.



                                           By:__________________________
                                                Blaine M. Jones
                                                Chief Financial Officer

ATTESTED BY:


By:____________________________
   Gary E. Risley, Secretary


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