FARNBOROUGH - Bombardier says modifications to the PW1500G engine are being tested. If proven successful, it would allow the test fleet to return to the air in the coming weeks. Mike Arcamone, President Bombardier Commercial Aircraft, says the modifications are being validated and the “testing is progressing well. We are confident.”

According to Arcamone, Pratt & Whitney has identified an engine fix following what has been described as an uncontained engine failure on May 29. FTV-1, the first test aircraft, was involved in the incident and all four test aircraft have been grounded since. Until flying was suspended the four jets had accumulated a total of around 330 hours. According to Bombardier, the full test program is planned for 2,400 hours and certification of the CS100 is due in the second half of 2015. Arcamone declined to specify details of the fix, referring questions to Pratt & Whitney.

According to Arcamone, Bombardier has been using the ground time for “a lot of software drops” as updates for the fleet are becoming available. But after test flights have resumed, Bombardier will have to accelerate the program to make up for the lost time in the air.

The company could be announcing more orders for the aircraft during the Farnborough Airshow. Orders for the Cseries or other Bombardier models could come from Asia where some sales campaigns are “far advanced. We will hopefully see the results in the coming days,” Arcamone says. Bombardier has 203 firm orders for the aircraft plus another 268 commitments.

Bombardier went into the show with a preliminary order for 24 more CS100s in the bag. UK-lessor Falko Regional Aircraft signed letters of intent for the type. Falko already has CRJ900s, CRJ900 NextGens and Q400s in its portfolio.