Lease Amendment
                          (Airport Plaza Office Lease)

This Lease  Amendment,  dated as of January 12, 2000, is by and between Highline
Group  LLC  ("Landlord"),  as  receiver  for the  Airport  Plaza  Building  (the
"Building") and Frontier Airlines, Inc. ("Tenant").

                                    Recitals

A.       Landlord and Tenant  entered into the Lease  Agreement, dated March 15,
         1994, as amended from time to time  and  which  covers Spaces 100, 110,
         120,  121,  190, 200, 300, 350, 360, 400, 450, 470, 500, 605, 610, 615,
         and 620 in the Building (the "Lease").
B.       The date for the  expiration of the Lease  concerning  spaces 110, 120,
         200,  350,  360,  400,  605,  610, 615, and 620 is August 31, 2000 (the
         "2000 Expiration Spaces").
C.       The date for the  expiration of the Lease  concerning  spaces 100, 121,
         190, 300,  450, 500, and 470 is January 31, 2001 (the "2001  Expiration
         Spaces").
B.       Landlord and Tenant desire to modify the Lease as set forth below.

                                    Agreement

         Now, therefore,  for good and valuable  consideration,  the receipt and
sufficiency  of  which is  hereby  acknowledged,  the  parties  hereto  agree as
follows:

1.       The  term of the Lease for the 2000 Expiration Spaces shall be extended
         *.
2.       The  minimum  rent  payable  monthly  under  the  Lease  for  the  2000
         Expiration  Spaces shall be: $* ($* per square  foot) from  February 1,
         2000 to August 31, 2000,  and $* ($* per square foot) from September 1,
         2000 to January 31, 2001.  Tenant's  base year for the 2000  Expiration
         Spaces shall be the year 2000.
3.       All of the  terms  and  conditions  of the  Lease  concerning  the 2001
         Expiration  Spaces shall remain unchanged and the Tenant shall continue
         to pay rent and operating expense  reimbursements  equal to $*per month
         for the 2001 Expiration Spaces.
4.       Tenant  shall continue to pay for the remainder of the term of the 2000
         Expiration Spaces and the 2001  Expiration Spaces a monthly after hours
         reimbursement to Landlord in the amount of $*
5.       The expiration date for space 500 shall be extended to May 31, 2001 and
         Tenant shall pay Landlord monthly during such extended term (a) minimum
         rent and  operating  expense  reimbursements  equal to $*and  (b) after
         hours reimbursement equal to $*
6.       Tenant  shall  lease from  Landlord,  effective  the date of this Lease
         Amendment  through January 31, 2001 the following  additional spaces in
         the building:  Suite 122 at *square feet, Suite 440 at *square feet and
         Suite 600-A at *square  feet.  The minimum rent and  operating  expense
         reimbursements  payable  for such space  shall  equal $* ($* per square
         foot) per month from the date of this Lease  Amendment  to January  31,
         2001.  Tenant's base year for the suites  identified in this  paragraph
         shall be the year 2000.
7.       Tenant shall pay to Landlord a damage  deposit in the amount of $* that
         shall be returned to Tenant  within * days after the  expiration of the
         term of the  Lease  if  Tenant  has  satisfied  all of the  obligations
         contained in the Lease upon its  expiration.  Such damage deposit shall
         be placed in an interest  bearing  account and if the damage deposit is
         returned to Tenant as set forth above,  Tenant shall be entitled to the
         interest earned on such account.
8.       If Tenant and Landlord enter into a long term agreement  whereby Tenant
         leases from Landlord space for its reservation  center in the building,
         Landlord  will credit  Tenant for the amount of rent Tenant has paid to
         Landlord pursuant to paragraph 2 above that exceeds $* per square foot.

To the extent that any term of this Lease Amendment shall conflict with any term
in the Lease, or any amendment or term sheet related thereto,  the terms of this
Lease Amendment shall supercede such  conflicting  term and this Lease Amendment
shall control.  Except as modified  herein all of the other terms and conditions
of the Lease shall remain unchanged and in full force and effect.

Landlord
Highline Group, LLC
As receiver for Airport Plaza

By:______________________
     Name:_______________
    Title:_______________

Tenant
Frontier Airlines, Inc.

By:______________________
     Name:_______________
    Title:_______________