An unlatched oil reservoir cap touched off a series of events that led to the 2011 crash of a Northern Thunderbird Air (NT Air) King Air 100 as its pilots turned back to Vancouver International Airport (CYVR) because of an oil leak, the Transportation Safety Board of Canada (TSB) says.
The two pilots were killed in the Oct. 27 crash, and all seven passengers were seriously injured. The airplane was destroyed.
The TSB said in its final report on the accident that, although considerable oil had leaked because of the unlatched cap, “enough remained to allow the engine and propeller to operate normally.”
The accident flight began around 1541 local time with takeoff from CYVR, where the airplane had been kept in a hangar overnight. It was inspected in the hangar by NT Air maintenance personnel, who added 1 L (1 qt) of oil to the left engine and signed off the overnight inspection as complete.
“It is likely that the oil cap was not secured or verified during completion of the overn…
