Search Results for Lights

Initial investigation showed that a landing gear failure was the result of a hard landing with no evidence of contributory factors. The objective of reexamination was to determine whether there was any evidence of metallurgical failure. The landing gear was primarily an AISI type 6150 Cr-V steel flat spring attached at the top end to the fuselage and at the bottom end to the axle. Failure occurred at the clamping point near the top end of this spring. The failure showed evidence of severe brinelling at one corner in the clamping area. The fracture surfaces were clean, fresh, and indicative of a shock type of failure pattern. Closer examination, however, showed a fatigue crack at one corner. At this point, there was definite evidence of progression and oxidation. It was concluded that the corner in question was subjected to repeated brinelling resulting from normal landing loads, probably accentuated by looseness in the clamping device. The resulting residual tensile stress lowered the effective fatigue strength at that point against drag and side loads.

A 1984 Chevrolet Blazer was being pushed by three youths after it ran out of gas when it was hit from behind by a 1979 Mercury Cougar. One of the youths was crushed between the two vehicles and killed. Optical microscopy was used to examine the tungsten filaments from the headlamps of the Cougar and from the four signal/emergency/parking lights of the Blazer to determine whether the vehicles lights were in use at the time of the accident. Based on degree of distension and brittle fragmentation, it was determined that the low-beam headlights of the Cougar and the parking lights of the Blazer were on at the time of the collision.