United Air Lines, Inc.

P. O. Box 66100

Chicago, IL 60601-0100

Subject:

[CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT] Matters

Reference:

Purchase Agreement No. 3427 (Purchase Agreement) between The Boeing Company (Boeing) and United Air Lines, Inc. (Customer) relating to Model 787-8 aircraft (Aircraft)

This letter agreement (Letter Agreement) amends and supplements the Purchase Agreement but is not part of the Purchase Agreement. All terms used but not defined in this Letter Agreement have the same meaning as in the Purchase Agreement.

Definition of Terms:

[CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

1. Notification.

Boeing will give written notice to Customer as soon as Boeing concludes that [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

2. [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

3. [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

4. [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

5. [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

6. [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT]

[CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT] Matters

BOEING / UNITED PROPRIETARY

UNITED AIR LINES, INC.

6-1162-ELP-0784

7. [CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT].

8. Assignment.

The rights and obligations described in this Letter Agreement are provided to Customer in consideration of Customer becoming the operator of the Aircraft and can only be assigned, in whole or in part, pursuant to Article 9 of the AGTA as amended by Letter Agreement No. 6-1162-IRS-0184.

9. Confidential Treatment.

Customer and Boeing agree and understand that this Letter Agreement is strictly confidential and only be shared with employees of Boeing and Customer but not with consultants or any other professional advisors who are not employees of the either party without prior consent of the other party. Customer and Boeing understand that certain commercial and financial information contained in this Letter Agreement are considered by Boeing and Customer as confidential and are subject to the terms and conditions set forth in Letter Agreement No. 6-1162-IRS-0182.

[CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT] Matters

BOEING / UNITED PROPRIETARY

UNITED AIR LINES, INC.

6-1162-ELP-0784

Notwithstanding above, Customer and Boeing agree and understand that this Letter Agreement is strictly confidential and only be shared with employees of Boeing and Customer but not with consultants or any other professional advisors who are not employees of the either party without prior consent of the other party.

Very truly yours,

THE BOEING COMPANY

By

/s/ Nobuko Wiles

Its

Attorney-In-Fact

ACCEPTED AND AGREED TO this

Date: February 19, 2010

UNITED AIR LINES, INC.

By

/s/ Kathryn A. Mikells

Its

Executive Vice President and Chief Financial Officer

[CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SEC PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT] Matters

BOEING / UNITED PROPRIETARY