�  � �   �    �� �   !"##$ % &'!('") *+,+-./.0120 324+0.25+1-615.*7  !"##$ % &'!(89$ :; 615.*7  !"##$ % &'!('"( 77+/2<.25615.*7  !"##$ % &'!(($9...

Exhibit 10.6 CERTAIN IDENTIFIED INFORMATION HAS BEEN EXCLUDED FROM THE EXHIBIT BECAUSE IT IS BOTH NOT MATERIAL AND IS THE TYPE THAT THE REGISTRANT TREATS AS PRIVATE OR CONFIDENTIAL. OMITTED INFORMATION HAS BEEN REPLACED WITH XXXXXXXXX. Supplemental Agreement No. 2 to Purchase Agreement No. 03776 between The Boeing Company and United Airlines, Inc. Relating to Boeing Model 737-9 Aircraft THIS SUPPLEMENTAL AGREEMENT, entered into as of January 14, 2015, by and between THE BOEING COMPANY (Boeing) and UNITED AIRLINES, INC. (a Delaware corporation formerly known as Continental Airlines, Inc. and successor by merger to United Air Lines, Inc.) (Customer); WHEREAS, the parties hereto entered into Purchase Agreement No. 03776 dated July 12, 2012, as amended and supplemented (Purchase Agreement), relating to the purchase and sale of Boeing model 737-9 aircraft (Aircraft). This Supplemental Agreement is an amendment to the Purchase Agreement; WHEREAS, Boeing and Customer agree to *** the following *** model 737-*** aircraft (*** Aircraft) in lieu of *** model 737-*** aircraft (*** Aircraft) pursuant to Supplemental Agreement No. 62 to Purchase Agreement No. 1951: *** Aircraft *** Aircraft MSN Delivery Month Delivery Month *** *** *** WHEREAS, Boeing and Customer agree to *** the following *** model 737-*** Option Aircraft ( *** Options): Delivery Month Quantity *** *** UAL-PA-03776 SA-2 Page 1 BOEING / UNITED AIRLINES, INC. PROPRIETARY �             �   ! "    ###  $! %&   '  ###   ' !  ### (    ###   '( )*(   !   '    $      !        !       '+,- ) % ' " !   ) ) % ' "   !    & +   ) % ' "     !   ! '   �      ) %) % -  $! !  !    & +   ) % -     !   ! '    �     .      /"000.0-11   !    & +       /"000.0-11    !   ! '    �     1 "!    !, )  �      +  % ' $ %2    '   '  '  '+  !   ! 3 $&  456789856: ;<=>=7=69?, 1-@  ' �             -AB- %+   ! "      !   'C ! 1@  '       1D %+   ! "       !   '/   '   '  "!    !       +  % !!  % !   @    $ !!  '  !   ' !   ! +     ' '  ! ' /.00 �0   EFGHIJ K LIHMGN OHPQHIGRS HI4T ;PF;PHGMOPU �               !   "  # $ # $ "%  & % '( )*+ ,-+./0 1-234/5 6/.)+7 4.89./+:; ./1<== �    # == > # ! #  �%   �%   $?%?@  �% A%  %# B @% C    #     % % !?? �?   ,-+./0 D 6/.)+7 4.89./+:; ./1< 38-38.+)485 �  � �    �     !!"#$  %  "&'(! )  * +  *, -  !! .,# �    /0/ , .123)345 6789�    /: /;  <  /"&=>,#!=#$ #1# ??  �89� @  @# !A#,B/,!C$ D# <D@  <D@E1# :'  :# ,'$$ E1# @@  @;FGGG 'H*  '&H/* : ,$ # ��I  � J:K4*4L)33M4H4%L3M)3 GGG# J:K4*4L)33M4H4%L3M)N GGG J:K4*4L)33M4H4%L3M+L ", # D;(F& J:K4*4L)33M4H4%L3M+) C$# J:K4*4L)33M4H4%L3M++ C$ / 67J:K4*4L)33M4H4%L3M+M * ,  '$$  J:K4*4L)33M4H4%L3M+3 '*(#!@>$, J:K4*4L)33M4H4%L3M+5 '$*#0* &# ; J:K4*4L)33M4H4%L3M-L '$# J:K4*4L)33M4H4%LNL-- GGG J:K4*4L)33M4H4%LN%% GGG J:K4*4L)33M4H4%LN%) GGG# J:K4*4L)33M4H4%LN-3 GGG J:K4*4L)33M  .<H@CD:CO.@O.'  '4%*; /% IP �Q R S??�T

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