DORVAL, Que. - The Transportation Safety Board has shed light on what caused a fire during ground tests of Bombardier's CSeries passenger jet two years ago.
The independent agency says there was a seal failure on an oil feed tube in the left engine of the CS100 plane during the May 29, 2014, incident at Montreal's Mirabel airport.
The safety board says the malfunction led to a failure of a turbine rotor and a subsequent fire, which was extinguished by Bombardier ground personnel.
Nobody was hurt.
Bombardier grounded the CSeries test aircraft until the cause of the fire was determined.
The board says engine supplier Pratt & Whitney has revised the cool-down procedure and made other changes to prevent a recurrence of the overheating that caused the seal to fail.
The CSeries program is 2 1/2 years behind schedule and at least $2 billion above cost estimates.
Swiss International Air Lines is the first carrier to accept the plane for commercial service. The airline took possession of its first CS100 on June 29 and is scheduled to put the plane into regular service on July 15.
