WARRANT
SUPPLEMENT TO
THE WARRANT
TO PURCHASE
COMMON SHARES
OF
FRONTIER AIRLINES, INC. This
Warrant Supplement (this Warrant Supplement) to the Warrant to purchase
Common Shares of Frontier Airlines, Inc., a Colorado corporation (Frontier), issued
to the Air Transportation Stabilization Board, with its principal office at
1120 Vermont Avenue, Suite 970, Washington, D.C. 20005 and/or its transferees
and assigns (individually or collectively, the Holder), on February 14, 2003
(the Warrant) is entered into as of March 31, 2006 by and between Frontier
Airline Holdings, Inc., a Delaware corporation (Frontier Holdings), and
Holder. RECITALS A. On
January 31, 2006, Frontier entered into that certain Agreement and Plan of
Merger (the Merger Agreement) with Frontier Holdings, a wholly owned
subsidiary of Frontier, and FA Sub, Inc., a Colorado corporation and a wholly
owned subsidiary of Frontier Holdings (Merger Sub), to effect the
reorganization of Frontier into a Delaware holding company structure. B. At
the date and time when the Merger (as defined below) becomes effective (the
Effective Time), pursuant to the transactions contemplated by the Merger
Agreement and on the terms and subject to the conditions thereof: (i) Merger
Sub, in accordance with the Colorado Business Corporation Act, will merge with
and into Frontier, with Frontier as the surviving corporation, becoming a
wholly owned subsidiary, directly and indirectly, of Frontier Holdings (the
Merger), (ii) each share of common stock of Frontier (Frontier Common
Stock) (other than such shares held by Frontier Holdings, which shares will
continue to be outstanding and held by Frontier Holdings) will be converted
into the right to receive one share of the common stock of Frontier Holdings
(Frontier Holdings Common Stock), (iii) each share of Frontier Holdings
Common Stock held by Frontier (being the 1000 shares issued upon the formation
of Frontier Holdings) will be canceled, and (iv) the Warrant will (until the end
of the Exercise Period as defined in the Warrant) evidence the right to
receive, upon exercise of the Warrant, in lieu of the shares of Frontier Common
Stock deliverable upon such exercise immediately prior to the Merger, the kind
and amount of Frontier Holdings Common Stock equivalent to what the Holder
would have been entitled to receive upon the Merger had the Holder exercised
the Warrant immediately prior to the Merger. NOW, THEREFORE, the
parties hereby amend
the Warrant as follows:   1. Assumption.
Frontier Holdings, in accordance with Section 5.3 of the Warrant, expressly
assumes (a) the obligation to deliver to Holder such shares of Frontier
Holdings Common Stock as the Holder is entitled to purchase, and (b) all other
obligations and liabilities under the Warrant, including obligations and
liabilities in respect of subsequent adjustments that are required under the Warrant.

2. No
Other Changes. Except as otherwise expressly provided by this Warrant
Supplement, all of the terms, conditions and provisions of the Warrant remain
unaltered and in full force and effect. This Warrant Supplement and the Warrant
shall be read and construed as one agreement.

3. Effective
Time. This Warrant Supplement will become effective at the Effective Time.

4. Counterparts.
This Warrant Supplement may be executed in any number of counterparts, each of
which will be deemed an original but all of which together will be deemed but
one and the same instrument.

[Signature Page Follows]

2

IN
WITNESS WHEREOF, the parties hereto have caused this Warrant Supplement to be
duly executed in its name and on its behalf, all as of the date first written
above.

FRONTIER HOLDINGS:
FRONTIER AIRLINES HOLDINGS, INC.By:Name:Title:HOLDER:
AIR TRANSPORTATION STABILIZATION
  BOARDBy:Name:Title: