About 1127 P.s.t., on January 20, 1981, a Cascade Airways, Inc., Beech 99A, operating as Flight 201, crashed during an instrument approach in instrument meteorological conditions at Spokane International Airport. The aircraft hit a hill about 4.5 miles from the runway threshold at an elevation of 2,646 feet. The minimum descent altitude for the instrument approach procedure was 2,760 feet. Of the nine persons aboard Flight 201, seven were killed and two were injured seriously. The instrument approach procedure the flightcrew used required that an altitude of 3,500 feet be maintained until the aircraft passed the final approach fix, located 4.5 miles from the runway threshold. The aircraft impacted the ground near the location of the final approach fix, which was about 1,800 feet southeast of the Spokane VORTAC. The National Transportation Safety Board determines that the probable cause of the accident was a premature descent to minimum descent altitude (MDA) based on the flightcrew's use of an incorrect distance measuring equipment (DME) frequency and the flightcrew's subsequent failure to remain at or above MDA. Contributing to the cause of the accident was the design of the DME mode selector which does not depict the frequency selected and the failure of the flightcrew to identify the localizer DME facility.
Aircraft Accident Report--Cascade Airways, Inc., Beechcraft 99A, N390CA, Spokane, Washington, January 20, 1981
1981
39 pages
Report
Keine Angabe
Englisch
Beechcraft Support for the Beechcraft 99
NTIS | 1967
|Engineering Index Backfile | 1938