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Exhibit 23.1
AIRCRAFT INFORMATION SERVICES, INC.
26072 Merit Circle, Suite 123
Laguna Hills, CA 92653
July 19, 2000
UNITED AIR LINES, INC.
1200 East Algonquin Road
Elk Grove Township, Illinois 60007
Re: PRELIMINARY PROSPECTUS SUPPLEMENT, DATED JULY 19, 2000 TO THE PROSPECTUS
DATED JULY 19, 2000, INCLUDED IN REGISTRATION STATEMENT NO. 333-90657 OF
UNITED AIR LINES, INC.
Ladies and Gentlemen:
We consent to the use of the report prepared by us with respect to the
aircraft referred to therein, to the summary of such report in the text under
the headings "Prospectus Supplement Summary--Equipment Notes and the Aircraft,"
"Risk Factors--Appraisals and Realizable Value of Aircraft," "Description of the
Aircraft and the Appraisals--The Appraisals" and "Experts" in the above-
captioned Preliminary Prospectus Supplement and to the references to our name
under the headings "Description of the Aircraft and the Appraisals--The
Appraisals" and "Experts" in such Preliminary Prospectus Supplement. We also
consent to such use, summary and references in the Final Prospectus Supplement
relating to the offering described in such Preliminary Prospectus Supplement, to
the extent such use, summary and references are unchanged.
Sincerely,
AIRCRAFT INFORMATION SERVICES, INC.
/s/ John D. McNicol
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Name: John D. McNicol
Title: Vice President
Appraisals & Forecasts
