Page:NTSB Aircraft Accident Report, United Airlines Flight 389.pdf/39

 considers the fact that the last communication from the flight which ended at 2220.03 made reference to the altimeter setting.

There has been no evidence recovered to date which will substantiate any pre-impact difficulties with the aircraft. The crew was in radio contact with approach control at a point in time that was about 3–4 miles, or about one minute away from the accident site, and reported no difficulties. There has been no evidence recovered that will substantiate a finding regarding a malfunction of the altimeters. In fact, the SAGE altitude data correlates favorably with the aircraft's reported altitude when such correlation is made in cruising flight. There is no history of altimeter problems in the aircraft's maintenance records and there were no altimeter writeups reported by the crew that flew the aircraft into New York.

A review of Attachment No. 2 shows the position of the hands of the altimeter could be misinterpreted under certain operating conditions and the crew could have misread 6,000 feet to be l6,000 feet. It is believed the first officer was flying the aircraft. The captains voice was identified on the air traffic control tapes and it is a normal custom in air carrier operations to have the pilot who is not flying the aircraft make the radio transmissions. If the captain were looking outside the aircraft for traffic or occupied with cockpit duties such as the completion of a checklist, and the first officer misread the altimeter, this error could escape undetected. To have such an error occur, however, it would be necessary for the pilot or pilots to fail to see the gradually increasing display of the cross–hatched warning section of the altimeter and the gradually decreasing display of the