Aug. 30, 2015
During the climb to cruise altitude, the pilot noticed a loss of engine oil pressure. He declared an emergency with ATC and requested to return to the airport. After ATC acknowledged, the pilot advised ATC that he lost all engine power and had to make an emergency landing. During the forced landing, the airplane collided with a ditch and was destroyed by post-crash fire.
An examination of the engine revealed that it failed catastrophically, displaying signatures of lubrication distress; further, no measurable quantity of oil could be recovered from within the engine. Detailed examination of the engine’s turbochargers revealed that one of the two units displayed evidence of burnt oil on the external surface and evidence of a foreign material in the unit’s center housing, on the thrust bearing, and on the thrust collar. The foreign material was identified as polyethylene (plastic), similar to that used to protect the exposed orifices of the engine during shipment. The pilot/mechanic had replaced both turbochargers with overhauled units two days before the accident flight.
Good article, Ron. I would like to understand more about the plastic cap that was not removed. As a novice with no turbocharger experience, I want to understand this. If the cap was left in place, wouldn’t that have been detected in after installation testing/run up? Thanks.
It’s a very thin plastic sheet that covers the open area. Kind of like plastic stretched across a bottle opening to protect the insides from going stale. It’s usually transparent (probably shouldn’t be) and could be overlooked…as it apparently was here. As soon as the engine started it would rupture (it’s thin) and then…apparently it will melt and clog up oil passages.
Thanks… So, an oil hose fitting had to be connected to the turbocharger with the plastic cap covering the fitting? Or is the cap covering some other opening?
The turbocharger center section has a two-bolt flange on the top and bottom; oil in, oil out. Aircraft-supplied fittings attach to those flanges. Both of the flanges come with some kind of plastic male plug or fitting for shipping. Removing those plugs before installing the aircraft-supplied fittings is expected. In the case of the accident described, it’s clear that may not have happened.