D1/​2010L Busi­ness Jet Dual En­gine Flame­out Dur­ing Taxi­ing at Helsinki-Van­taa Air­port on 6 March, 2010

18.01.2013

An incident occurred at Helsinki-Vantaa airport on Saturday, 6 March 2010 at 10:15 Finnish time when the both engines of a Bombardier Learjet 60 simultaneously flamed out during taxiing.

The investigation found no explicit cause for the dual flameout. On the basis of the conducted investigations however, the probable cause of the flameout event was a disturbance of the fuel/air ratio in conjunction with a specific throttle movement and, particularly when the Lucas-manufactured Hydromechanical Units (HMU) were in use.

Safety Investigation Authority Finland recommends that Pratt & Whitney Canada continue the analysis of PW305A engine control units so as to determine and eliminate the root cause of the detected flameout tendency. It would be desirable if Transport Canada, as the issuer of the engine’s type certificate, would contribute to this process.

Safety Investigation Authority Finland further recommends that Transport Canada require the engine manufacturer to determine the root cause for the flameout tendency, and to propose the corrective action in eliminating the flameout tendency.