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Exhibit 10.20

Confidential treatment has been requested for portions of this document. This
copy of the document filed as an Exhibit omits the confidential information
subject to the confidentiality request. Omissions are designated by the symbol
[...***...]. A complete version of this document has been filed separately with
the Securities and Exchange Commission.

AMENDMENT NO. 1 TO AIR TRANSPORTATION CHARTER AGREEMENT

        This Amendment No. 1 to Air Transportation Charter Agreement
("Amendment") is made as of the 30th day of April, 2009, by and between
Allegiant Air, LLC, a Nevada limited liability company with principal offices at
8360 South Durango Drive, Las Vegas, Nevada 89113 ("Allegiant"), and Harrah's
Operating Company, Inc., a Delaware corporation with principal offices at One
Harrah's Court, Las Vegas, Nevada 89119 ("Charterer") (Allegiant and Charterer
shall each also be referred to as a "Party" or collectively as the "Parties").

        WHEREAS, Allegiant and Charterer are parties to that certain Air
Transportation Charter Agreement executed on October 31, 2008 (the "Agreement"),
and

        WHEREAS, Allegiant and Charterer have agreed that it is in the interest
of both Parties to enter into an amendment to the Agreement, and

        WHEREAS, Allegiant and Charterer have agreed to amend the Agreement
pursuant to Section 28.7 thereof;

        THEREFORE, in consideration of the promises, covenants, and provisions
below and the recitals above, Allegiant and Charterer hereby amend the Agreement
as follows:

        1.     Pursuant to the Agreement, Allegiant bases one MD-87 aircraft at
Reno/Tahoe International Airport, Reno, Nevada ("RNO") for the operation of
charter flights to and from RNO as set forth in the Agreement. This Amendment
affects only the RNO-based aircraft (the "RNO Aircraft"); all operations of
aircraft based at other locations continue to be subject to the terms and
conditions of the Agreement without reference to this Amendment.

        2.     Notwithstanding anything to the contrary in the Agreement, in the
case of all flights that (i) operate to or from RNO or are positioning flights
(also known as ferry flights) associated with the operation of such flights,
(ii) utilize the RNO Aircraft, and (iii) operate after June 30, 2009 but before
January 1, 2010, the following shall apply:

        (a)   The Price for Services shall be fixed at [...***...] per Actual
Block Hour flown and shall not be subject to adjustment based upon the price of
fuel; and

        (b)   Harrah's shall pay Allegiant for all Actual Block Hours flown,
provided that in the event the Actual Block Hours flown in any calendar month
are less than the minimum number of hours specified below, Harrah's shall pay
Allegiant for the number of hours specified below for that month:

July 2009:

  [...***...]

August 2009:

  [...***...]

September 2009:

  [...***...]

October 2009:

  [...***...]

November 2009:

  [...***...]

December 2009:

  [...***...]

        3.     This Amendment applies only to flights meeting all of the
conditions (i, ii and iii) specified in Paragraph 2 above.

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        4.     Harrah's agrees that in the event it proposes any amendment or
modification to the Agreement for effect on or after January 1, 2010, Harrah's
will furnish such proposal to Allegiant no later than August 3, 2009. The
Parties agree that any negotiation of such proposal shall be accomplished during
August 2009 and that to the extent agreement on the proposal or any
counterproposal is reached, the resulting amendment shall be executed no later
than September 1, 2009; failing which, the Agreement, as amended by this
Amendment No. 1, shall be unaffected by the proposal or any counterproposal.

        5.     Except as set forth in this Amendment, the terms and conditions
of the Agreement shall remain in full force and effect at all times. Capitalized
terms that appear in this Amendment and that are defined in the Agreement have
same meaning in both documents.

        IN WITNESS WHEREOF, the Parties have executed this Amendment No. 1 to
Air Transportation Charter Agreement as of the day and year first written above.

ALLEGIANT AIR, LLC   HARRAH'S OPERATING COMPANY, INC.
By
 
 

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By
 
    

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Title:
 
 

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Title:
 
    

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Exhibit 10.20

AMENDMENT NO. 1 TO AIR TRANSPORTATION CHARTER AGREEMENT