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                                                                   EXHIBIT 10.13

                            WORLD AIR HOLDINGS, INC.

                              EMPLOYMENT AGREEMENT

      This Employment Agreement between World Air Holdings, Inc., a Delaware
corporation ("World" or the "Company") and MARK M. McMILLIN ("McMillin") is
effective as of this 5TH day of MAY 2005.

      WHEREAS, McMILLIN has agreed to serve as World's GENERAL COUNSEL AND
CORPORATE SECRETARY as of MAY 5, 2005.

      NOW, THEREFORE, World and McMILLIN, in consideration of the foregoing and
other mutual covenants and promises contained herein, the sufficiency of which
are hereby acknowledged, hereby agree as follows:

      1. ACCEPTANCE OF EMPLOYMENT. Subject to the terms and conditions set forth
below, World agrees to employ McMILLIN and McMILLIN accepts such employment.

      2. TERM. The period of employment shall be from MAY 5, 2005, through MAY
6, 2008, unless further extended or sooner terminated as hereinafter set forth.
In the absence of notice, this Agreement shall be renewed on the same terms and
conditions for one year from the date of expiration. Not later than OCTOBER 6,
2007, McMILLIN shall initiate discussions with the Chief Executive Officer
(hereinafter "CEO") regarding the renewal of this Agreement. At that time, if
McMILLIN wishes to renew this Agreement on different terms, McMILLIN shall give
written notice to the CEO. If the CEO does not wish to renew this Agreement at
its expiration, or wishes to renew on different terms, the CEO shall give
written notice to McMILLIN no later than NOVEMBER 6, 2007.

      3. POSITION AND DUTIES. McMILLIN shall serve as GENERAL COUNSEL AND
CORPORATE SECRETARY with duties performed as of the date hereof, as those duties
may be changed from time to time. The CEO will have reasonable latitude to make
changes in McMILLIN'S responsibilities, except that McMILLIN'S responsibilities
may not be modified in a way that would

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be inconsistent with the status of GENERAL COUNSEL AND CORPORATE SECRETARY.
Following a Change of Control (as hereinafter defined), McMILLIN'S
responsibilities may not be changed without mutual agreement. McMILLIN agrees to
render his services to the best of his abilities and will comply with all
policies, rules and regulations of the company and will advance and promote to
the best of his ability the business and welfare of the Company. McMILLIN shall
devote all of his working time, attention, knowledge and skills solely to the
business and interests of World. McMILLIN may not accept any other engagement
with or without compensation, which would affect his ability to devote all of
his working time and attention to the business and affairs of World without the
prior written approval of the CEO. McMILLIN agrees to accept assignments on
behalf of World or affiliated companies commensurate with his responsibilities
hereunder, except that the terms and conditions of assignments exceeding 60
consecutive days outside the ATLANTA, GEORGIA Standard Metropolitan Statistical
Area will require mutual agreement.

      4. COMPENSATION AND RELATED MATTERS.

      (a) BASE SALARY. McMILLIN shall receive a minimum salary of $175,000 per
annum payable in accordance with the payroll procedures for World's salaried
employees in effect during the term of this Agreement. McMILLIN agrees to
participate equally, on a percentage basis, in any across the board salary
reductions approved by senior management.

      (b) PERFORMANCE STOCK OPTIONS. McMILLIN has previously been granted 25,000
OPTIONS to purchase World's Common Stock, par value $.001 per share ("World Air
Holdings, Inc. Common Stock") pursuant to the World Air Holdings, Inc. Amended
and Restated 1995 Stock Incentive Plan (the "Plan") as set forth in the Stock
Option Agreement between World and McMILLIN dated DECEMBER 22, 2004 (the "Option
Agreement"). In the event of a Change in Control as defined below, all Options
shall be immediately exercisable.

      (c) MANAGEMENT INCENTIVE PROGRAM. World's present "Management Incentive
Program" is currently under review and being revised. To the extent that any
such plan is eventually approved and implemented by the Company, McMILLIN shall
be entitled to participate in such incentive plan according to its terms.

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      (d) BUSINESS EXPENSES. McMILLIN shall be entitled to reimbursement of
reasonable business related expenses from time to time consistent with World's
policies, including, without limitation, submitting in a timely manner
appropriate documentation of such expenses.

      (e) FRINGE BENEFITS. McMILLIN shall be entitled to participate in all
employee benefit plans made available from time to time to all executives of
World in accordance with the terms of such plans. In the event this Agreement is
terminated by either party for any reason other than death or for cause,
McMILLIN may participate in World's health and other benefit programs for a
period of one year from the date of McMILLIN'S termination, or until McMILLIN
obtains comparable coverage, whichever is earlier.

      (f) PERSONNEL POLICIES, CONDITIONS AND BENEFITS. Except as otherwise
provided herein, McMILLIN'S employment shall be subject to the personnel
policies and benefits plans which apply generally to World's employees as the
same may be interpreted, adopted, revised or deleted from time to time, during
the term of this Agreement, by World in its sole discretion. While this
Agreement is in effect, McMILLIN shall receive twenty (20) DAYS OF VACATION, in
addition to sick leave, holidays, and such other leave as World may provide. All
such vacation and leave shall be taken in accordance with the Company's
procedures.

      (g) INDEMNIFICATION; D&O INSURANCE. Subject to Section 6(b) of this
Agreement, World shall provide (or cause to be provided) to McMILLIN
indemnification against all expenses (including attorneys' fees), judgments,
fines and amounts paid in settlements in connection with any threatened, pending
or completed action, suit or proceeding, whether civil, criminal, administrative
or investigative (including an action by or in the right of World) by reason of
his being or having been an officer, director or employee of World or any
affiliated entity, advance expenses (including attorneys' fees) incurred by
McMILLIN in defending any such civil, criminal, administrative or investigative
action, suit or proceeding and maintain directors' and officers' liability
insurance coverage (including coverage for securities-related claims) upon
substantially the same terms and conditions as set forth in the INDEMNIFICATION
AGREEMENT dated MAY 5, 2005, between McMILLIN and World Air Holdings, Inc. (the
"Indemnity Agreement").

      5. TERMINATION OF EMPLOYMENT.

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      (a) DEATH. McMILLIN'S employment hereunder shall terminate upon his death,
in which event World shall have no further obligation to McMILLIN or his estate
with respect to compensation, other than the disposition of life insurance and
related benefits and accrued and unpaid base salary and incentive compensation,
if any, for periods prior to the date of termination pursuant to the terms of
the respective employee benefits and incentive compensation plans then in
effect.

      (b) BY WORLD FOR DISABILITY. If McMILLIN is unable, or fails, to perform
services pursuant to this agreement through illness or physical or mental
disability and such failure or disability shall exist for twelve (12)
consecutive months, then World may terminate this Agreement upon written notice
to McMILLIN, in which event World shall have no obligation to McMILLIN with
respect to compensation under Section 4(a) of this Agreement. If McMILLIN
becomes entitled to Social Security benefits payable on account of disability,
he will be deemed conclusively to be disabled for purposes of this Agreement.

      (c) BY WORLD FOR CAUSE.

            (i) Except under the circumstances set forth in 5(c)(ii) below, the
            Chairman of the Board may terminate this Agreement for Cause.
            "Cause" shall be defined as (A) sustained performance deficiencies
            which are communicated to McMILLIN in written performance appraisals
            and/or other written communications (including, but not limited to
            memos and/or letters) by the Chairman, (B) gross misconduct,
            including significant acts or omissions constituting dishonesty,
            intentional wrongdoing or malfeasance, whether or not relating to
            the business of World, or (C) commission of a felony or any crime
            involving fraud or dishonesty, or (D) a material breach of this
            Agreement.

            (ii) In the event of a Change of Control, as defined below, McMILLIN
            may only be terminated for Cause pursuant to a resolution duly
            adopted by the affirmative vote of a majority of the entire
            membership of the Board, at a meeting of the Board finding that, in
            the good faith opinion of the Board, McMILLIN was guilty of conduct
            set forth in 5(c)(i)(A), or (B), provided, however, that McMILLIN
            may not be terminated for Cause hereunder unless: (1) McMILLIN
            receives prior written notice of World's intention to terminate this
            Agreement for Cause and the

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            specific reasons therefore; and (2) McMILLIN has an opportunity to
            be heard by World's Board and be given, if the acts are correctable,
            a reasonable opportunity to correct the act or acts (or non-action)
            giving rise to such written notice. If the Board, by resolution duly
            adopted by the affirmative vote of a majority of the entire
            membership of the Board, finds that McMILLIN fails to make such
            correction after reasonable opportunity to do so, this Agreement may
            be terminated for Cause.

      (d) BY WORLD FOR OTHER THAN CAUSE. In the event the Board terminates this
Agreement for reasons other than Cause or Disability as defined in sub-paragraph
(c) above, World will pay to McMILLIN within ten (10) days of notice of
termination (or, in the case of incentive bonus compensation, if any, within ten
(10) days of determination of amounts payable under the applicable bonus plan)
EIGHTEEN MONTHS (18) base salary, in each case including deferred salary and/or
bonus compensation, if any, payable under this Agreement. In addition, all
granted but unvested Options under the Option Agreements shall become
immediately exercisable. In the event that any payment to McMILLIN under this
paragraph is subject to any federal or state excise tax, World shall pay to
McMILLIN an additional amount equal to the excise tax imposed including
additional federal and state income and excise taxes as a result of the payments
under this paragraph, and such payment will be made when the excise tax and
income taxes are due; provided, however, that McMILLIN agrees to assist World
Air Holdings, Inc. by using his best efforts to structure matters so that any
payment to McMILLIN under this paragraph is not subject to any federal or state
excise tax. Whether an excise tax is payable, and the amount of the excise tax
and additional income taxes payable, shall be determined by World's accountants
and World shall hold McMILLIN harmless from any and all taxes, penalties, and
interest that may become due as a result of the failure to properly determine
that an excise tax is payable or the correct amount of the excise tax and
additional income taxes, together with all legal and accounting fees reasonably
incurred by McMILLIN in connection with any dispute with any taxing authority
with respect to such determinations and/or payments.

      (e) BY McMILLIN FOR GOOD REASON. McMILLIN may terminate his employment
hereunder (for purposes of this Agreement "Good Reason") after giving at least
30 days notice in the event that, without McMILLIN'S consent, (i) World
relocates its general and administrative offices or McMILLIN'S place of
employment to an area other than the Atlanta, Georgia Standard Metropolitan
Statistical Area, (ii) he is assigned any duties substantially inconsistent with
Section

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3 hereof, (iii) World reduces his annual base salary as in effect on the date
hereof or as the same may be increased from time to time, except as provided in
Section 4(a) above; (iv) World fails, without McMILLIN'S consent, to pay
McMILLIN any portion of his current compensation, or to pay him any portion of
an installment of deferred compensation under any deferred compensation program
of World, within seven (7) days of the date such compensation is due; (v) World
fails to continue in effect any compensation plan in which McMILLIN participates
which is material to McMILLIN'S total compensation, unless an equitable
arrangement (embodied in an ongoing substitute or alternative plan) has been
made with respect to such plan, or to continue McMILLIN'S participation therein
(or in such substitute or alternative Plan) on a basis not materially less
favorable, both in terms of the amount of benefits provided and the level of
McMILLIN'S participation relative to other participants; (vi) World fails to
continue to provide McMILLIN with benefits substantially similar to those
enjoyed by McMILLIN under any of World's pension, life insurance, medical,
health and accident, or disability plans in which McMILLIN was participating,
World takes any action which would directly or indirectly materially reduce any
of such benefits or deprive McMILLIN of any material fringe benefit enjoyed by
McMILLIN; (vii) World terminates, or proposes to terminate, McMILLIN'S
employment hereunder contrary to the requirements of Section 5(c) hereof (for
purposes of this Agreement, no such termination or purported termination shall
be effective); or, with or without McMILLIN'S consent (viii) the Board approves
the liquidation or dissolution or Change of Control of World prior to the end of
this Agreement. In the event that McMILLIN decides to terminate this Agreement
and his employment with World or any successor in interest in accordance with
the provisions of this Section 5(e), World shall have the same obligations as
set forth in Section 5(d) hereof. Any other payments due or actions required
under this paragraph shall be made as lump sums or taken within 10 days of
termination of the Agreement.

      (f) BY McMILLIN FOR OTHER THAN GOOD REASON. Notwithstanding the above,
McMILLIN may upon giving reasonable notice, not to be less than 30 days,
terminate this Agreement without further obligation on the part of McMILLIN or
World.

      (g) CHANGES OF CONTROL. For purposes of this Agreement, a "Change of
Control" includes the occurrence of any one or more of the following events:

            (i) any Person, other than the Company, is or becomes the Beneficial
            Owner (as defined in Rule 13d-3 under the Securities Exchange Act of
            1934, as amended

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            (the "Exchange Act")), directly or indirectly, of securities of
            World representing more than 50% of the combined voting power of
            World's then outstanding securities; or

            (ii) during any period of two (2) consecutive years (not including
            any period prior to the execution of this Agreement), individuals
            who at the beginning of such period constitute the Board of World
            and any new director (other than a director designated by a Person
            who has entered into an agreement with World to effect a transaction
            described in clause (i), (iii) or (iv) or this Section 5 (f)) whose
            election by the Board of World or nomination for election by the
            stockholders of World was approved by a vote of at least two-thirds
            (2/3) of the directors then still in office who either were
            directors at the beginning of the period or whose election or
            nomination for election was previously so approved, cease for any
            reason to constitute a majority thereof; or

            (iii) the shareholders of World approve a merger or consolidation of
            World with any other corporation, other than (A) a merger or
            consolidation which would result in the voting securities of World
            outstanding immediately prior thereto continuing to represent
            (either by remaining outstanding or being converted into voting
            securities of the surviving entity), in combination with the
            ownership of any trustee or other fiduciary holding securities under
            an employee benefit plan of World or any of its affiliates, at least
            50% of the combined voting power of the voting securities of World
            or such surviving entity outstanding immediately after such merger
            or consolidation, or (B) a merger or consolidation effected to
            implement a recapitalization of World (or similar transaction) in
            which no Person acquires more than 50% of the combined voting power
            of World's then outstanding securities; or

            (iv) the shareholders of World approve a plan of complete
            liquidation of World or an agreement for the sale or disposition by
            World of all or substantially all of World's assets.

      (h) "PERSON" DEFINED. For purposes of this Section, "Person" shall have
the meaning given in Section (3)(a)(9) of the Exchange Act, as modified and used
in Sections 13(d) and 14(d)

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thereof; however, a Person shall not include (i)World or any of its subsidiaries
or affiliates; (ii) a trustee or other fiduciary holding securities under an
employee benefit plan of World or any of its subsidiaries; (iii) an underwriter
temporarily holding securities pursuant to an offering of such securities; or
(iv) a corporation owned, directly or indirectly, by the stockholders of World
in substantially the same proportions as their ownership of stock of World.

      (i) NOTICE OF TERMINATION. Termination of this Agreement by World or
termination of this Agreement by McMILLIN shall be communicated by written
notice to the other party hereto, specifically indicating the termination
provision relied upon.

      (j) COMPANY PROPERTY. At the termination of McMILLIN'S employment, whether
voluntary or involuntary, McMILLIN shall return all company property, including
without limitation all electronic and paper files and documents and all copies
thereof.

      6. CONFIDENTIALITY.

      (a) McMILLIN recognizes and acknowledges that he will acquire during his
employment with World information that is confidential to World and that
represents valuable, special and unique assets of World ("Confidential
Information"). Such Confidential Information (whether or not reduced to tangible
form) includes, but is not limited to: trade secrets; financing documents and
information; financial data; new product information; copyrights; information
relating to schedules and locations; cost and pricing information; performance
features; business techniques; business methods; business and marketing plans or
strategies; business dealings and arrangements; business objectives; customer
information; sales information; acquisition, merger or business development
plans or strategies; research and development projects; legal documents and
information; personnel information; and any and all other information concerning
World's business and business practices that is not generally known or made
available to the public or to World's competitors or is not readily
ascertainable by other means, which, if misused or disclosed, could adversely
affect the business of World. McMILLIN agrees that he will not, during
employment with World and for a period of two (2) years following termination of
employment for any reason, whether voluntary or involuntary, with or without
Cause, directly or indirectly:

            (i) disclose any Confidential Information to any person, company or
            other entity (other than authorized persons employed by or
            affiliated with World who, in the interest of World, have a business
            need to know such information), or

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            (ii) use any Confidential Information in any way, except as required
            by his duties to World or by law, unless he obtains World's prior
            written approval of such disclosure or use. World's rights under
            this Section shall be cumulative to, and shall not limit, World's
            rights under the Georgia Uniform Trade Secrets Act or any other
            state or federal trade secret or unfair competition statute or law.
            The parties hereto stipulate that as between them, the foregoing
            matters are important, material, and confidential and gravely affect
            the successful conduct of the business of World, and World's good
            will, and that any breach of the terms of this paragraph shall be a
            material breach of this Agreement.

      (b) Section 4(g) of this Agreement and any other indemnity agreements
between McMILLIN and World shall not apply to actions, suits or proceedings to
enforce World's rights under, or that otherwise relate to, this Agreement,
including without limitation, this Section

      (c) References in this Section 6 to "World" include World Air Holdings,
Inc. and any and all of its current or future parents, subsidiaries, affiliated
companies, and divisions.

      7. BENEFICIARY. The Beneficiary of any payment due and payable at the time
of McMILLIN'S death, or otherwise due upon his death, shall be such person or
persons, as McMILLIN shall designate in writing to World. If no such beneficiary
shall survive McMILLIN, any such payments shall be made to his estate.

      8. INTELLECTUAL PROPERTY.

      (a) Any improvements, new techniques, processes, inventions, works,
discoveries, products or copyrightable or patentable materials made or conceived
by McMILLIN, either solely or jointly with other person(s), (1) during
McMILLIN'S period of employment by World, during working hours; (2) during the
period after termination of his employment during which he is retained by World
as a consultant; or (3) with use of World's intellectual property or
Confidential Information, shall be the sole and exclusive property of World
without royalty or other consideration to McMILLIN.

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      (b) McMILLIN agrees to inform World promptly and in full of such
intellectual property by a full written report setting forth in detail the
procedures used and the results achieved.

      (c) McMILLIN shall at World's request and expense execute any and all
applications, assignments, or other instruments which World shall deem necessary
to apply for, register, and/or obtain copyrights or Letters Patent of the United
States or of any foreign country, or to otherwise protect World's interests in
such intellectual property.

      (d) McMILLIN shall assign and does hereby assign to World all interests
and rights, including but not limited to copyrights, in any such intellectual
property.

      9. NO WAIVER. The failure of either party at any time to enforce any
provisions of this Agreement or to exercise any remedy, option, right, power or
privilege provided for herein, or to require the performance by the other party
of any of the provisions hereof, shall in no way be deemed a waiver of such
provision at the same or at any prior or subsequent time.

      10. GOVERNING LAW. All questions concerning the construction, validity,
application and interpretation of this Agreement shall be governed by and
construed in accordance with the laws of the STATE OF GEORGIA without giving
effect to any choice of law or conflict of law provision or rule (whether of
GEORGIA or any other jurisdiction) that would cause the application of the law
of any jurisdiction other than GEORGIA. McMILLIN agrees to submit to personal
jurisdiction in the STATE OF GEORGIA.

      11. VALIDITY. The invalidity or unenforceability of any provision or
provisions of this Agreement shall not be deemed to affect the validity or
enforceability of any other provision of this Agreement, which shall remain in
full force and effect.

      12. SUCCESSORS. This Agreement shall inure to the benefit of and be
binding upon World, its successors and assigns, including any corporation or
other business entity which may acquire all or substantially all of World's
assets or business, or within which World may be consolidated or merged, or any
surviving corporation in a merger involving World.

      13. WAIVER OF MODIFICATION OF AGREEMENT. No waiver or modification of this
Agreement shall be valid unless in writing and duly executed by both parties.

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      14. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which together will constitute one and the same
instrument.

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

                                                    WORLD AIR HOLDINGS, INC.

                                                    By: /s/ Randy J. Martinez
                                                        ------------------------
                                                        Randy J. Martinez
                                                        Chief Executive Officer

                                                        /s/ Mark M. McMillin
                                                        ------------------------
                                                        Mark M. McMillin

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