Bombardier has restarted engine ground runs for the CSeries test fleet 13 days after an uncontained engine failure, and reaffirmed entry-into-service is set for the second half of next year.
The company has introduced a new “control measures” to prevent the malfunction that occurred on engine No. 1 of the FTV-1 test aircraft on 29 May, Bombardier says.
The new procedure was adopted after Bombardier and engine supplier Pratt & Whitney developed a “good understanding of what happened” on 29 May, Bombardier says, without elaborating.
Bombardier and P&W parent United Technologies officials have previously confirmed the source of the uncontained failure was in the low-pressure turbine of the PurePower PW1500G geared turbofan.
The CSeries fleet will resume flight tests in the “coming weeks”. The grounding, however, means there is now no chance for the CSeries to make a debut appearance at the Farnborough air show that starts on 14 July, Bombardier says.
Bombardier is considering other venues to “showcase” the CSeries, although the next major international air show is not until Paris in June 2015.
The uncontained failure caused structural damage to the airframe of FTV1. But Bombardier says the repairs are “manageable”.
Meanwhile, Bombardier is also running stationary tests of the auxiliary power unit, electrical systems and avionics.
The engine malfunction occurred as the CSeries test fleet was starting to gain momentum after a slow start.
The four CSeries CS100 aircraft delivered to the flight test programme so far have accumulated a combined 330 flight test hours since first flight on 16 September.
The CSeries is the first commercial aircraft to enter certification flight testing with a variant of P&W’s family of geared turbofan engines, which are also selected to power the Airbus A320neo, the Irkut MS-21, Mitsubishi MRJ-90 and the Embraer E-Jet E2.
The novel feature of the engine – the fan-drive gear system – has not been directly implicated in the source of the engine malfunction on 29 May.
The fan-drive gear systems allows P&W to de-couple the rotation speed of the low-pressure turbine and the inlet fan, allowing each to spin at the most efficient speed. The fan is slowed down by the gear, while the LPT rotation speed increases significantly.