Page:CAB Accident Report, Eastern Air Lines Flight 21.pdf/15

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altitude at which the aircraft flew at all times during its flight from New York. It showed a practically constant cruising altitude of 4,000 feet between New York and Washington and between Washington and the vicinity of Atlanta. The chart also showed a normal descent and ascent at Washington and a steady descent in the vicinity of Atlanta continuing from approximately the time the pilot reported over Stone Mountain until the time of the crash. The chart contained no indication of any abnormal operation of the aircraft in the period preceding the crash. However, the information contained therein is not sufficiently exact to allow for an accurate determination of the altitude of the aircraft at any particular location after its descent was begun in the vicinity of Atlanta.[1]

In the wreckage were found two sensitive type Kollsman altimeters which had been torn from the instrument panel and lay partially buried in mud. An examination of the barometric scale settings of these altimeters at the scene of the crash showed a setting of 30.33 inches of mercury in altimeter No. 031-2522 and 29.92 inches of mercury in altimeter No. 01-1366. Altimeter No. 031-2522 was the one used in route flying and was kept adjusted to sea level barometric pressure. This setting as supplied by the United States Weather Bureau for the Washington station at 8:35 p.m. (EST) was 30.23, and as supplied by the Weather Bureau for the Atlanta station at 10:35 p.m. (CST) was 30.02. Altimeter No. 01-1366 was the one used for instrument approaches and should have been adjusted

  1. The chart upon which the altitude is registered has such a small time interval scale that it fails to show exactly the maneuvers of the aircraft in the short period between the beginning of its descent at Stone Mountain and its subsequent crash. This period of 10 minutes embraces no more than an eighth of an inch of the scale of the chart and an enlargement only serves to distort the size of the altitude line in relation to the scale.