What happened
On a pleasure flight traveling from Yellowknife, Northwest Territories, to Kelost, British Columbia, an amateur-built Glastar, registration C-GMDP, experienced a sudden engine malfunction. While flying near Chetwynd, the aircraft encountered severe vibrations and a significant loss of power, which caused the engine speed to drop to 1000 rpm. The pilot attempted a forced landing in a nearby field.
During the final approach, the aircraft struck power lines, which caused it to veer right and collide with trees and rising terrain. The impact occurred approximately six miles south-southwest of Chetwynd. The accident resulted in one fatality and one injury. The aircraft's emergency locator transmitter (ELT) failed to activate because the switch was in the OFF position.
The investigation
Investigators examined the wreckage and identified that the number two cylinder head had separated from its base. This failure caused the crankshaft to sever at the propeller flange. At the time of the accident, the engine had recorded 212 hours since new. While compression checks had been performed 22 hours prior, they failed to identify the impending failure.
Technical analysis also revealed evidence of minor hydrogen embrittlement in the crankshaft, though this was not determined to be the cause of the crash. The investigation also looked into the regulatory environment regarding airworthiness directives (ADs) for non-type-certificated aircraft.