Page:NTSB Report, 1967 Lear Jet crash.pdf/11

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The Jackson surface weather observation at 1900 was in part: measured ceiling 500 feet overcast, visibility 3 miles, very light drizzle, fog, temperature 50 degrees. The 1945 Detroit Metropolitan Airport radar weather observation, including the Jackson area, showed a scattered area of echoes containing light and very light rain showers, decreasing slowly in intensity. The tops of detectable moisture were at 22,000 feet m.s.l. The Chicago radar weather observation at 1942 revealed no echoes in the vicinity of Jackson. The 1900 Flint winds aloft observation was in part as follows:

Height Direction (True) Velocity
20,000 feet 200 degrees 22 knots
23,000   190   35  
25,000   210   45  

Moonset at Jackson was 1646.

Statements were obtained from the pilots of three flights who were in the vicinity of the accident site near the time of the accident. One aircraft departed Willow Run Airport at 1930. The pilot stated, "The ceiling just northeast of Willow Run was approximately 900 feet. During climb westbound, several cloud layers were encountered, but by the time the flight reached a position some 40 miles west, or just north of Jackson, Michigan, at approximately 1940 e.s.t., it was on top and in the clear. Tops in the area were estimated to be 10,000–11,000 feet. No ice was detected in clouds during climbout, nor was any turbulence encountered." Another flight which was holding west of Jackson at FL 260 reported experiencing moderate chop, but was unable to recall the cloud conditions. The Cleveland ARTCC controller stated that this flight was in the same general vicinity as N804LJ when it disappeared.