An engine fire two years ago that grounded Bombardier's CSeries test aircraft fleet has been blamed on a series of technical malfunctions. The investigation found that the makers of the engine, Pratt & Whitney, had issued instruction for the engine's proper cooling. Following the grounding of the C Series test aircraft fleet Pratt & Whitney proposed a plan to prevent the hot shutdowns which led to the fire. Bombardier's interpretation of the instructions however led to the engine enduring too many hot shutdowns. In May 2014, pilots and engineers were testing a Bombardier CS100 at the Mirabel Airport when smoke and fire erupted in the aircraft's left engine.

Source: CBC News July 05, 2016 17:15 UTC