Bombardier said its CSeries flight-test program is progressing as planned, and its “target” remains to complete the program and certify the new airliner one year after first flight, or by next September. However, the manufacturer said that it is discussing a definitive schedule for the five-aircraft test program with its suppliers and customers. It will reveal the schedule “in the next few months,” according to Pierre Beaudoin, president and CEO.

“We want to make sure that we understand the progression on these aircraft, the exact date when they start to fly, the commitment of all the suppliers during the flight-test [program] and also their commitment toward delivering production parts,” Beaudoin said on October 31 during a teleconference to discuss third-quarter 2013 financial results. “There [are] many things to analyze before we get back with a definite schedule.”

The CSeries FTV1 prototype, powered by new Pratt & Whitney PurePower turbofans, made its first flight on September 16 from Montreal’s Mirabel International Airport, nearly nine months later than originally planned. Bombardier conducted the fourth test flight, lasting 1.5 hours, on October 30, more than seven weeks after first flight.

The manufacturer said that it updated the aircraft’s fly-by-wire flight control system software “as planned” between the third and fourth test flights and also conducted some vibration testing that wasn’t done before the first flight. Five CS100 prototypes will participate in the flight-test program. Beaudoin said the second flight-test vehicle will take flight within weeks.

In an investment report on October 28, UBS Securities asserted that Bombardier’s planned 2,400-hour flight-test program leading to certification and entry into service of the 110-seat CS100 version one year after first flight appears to be behind schedule. To complete the allotted hours, Bombardier would need to fly 1.8 hours per aircraft per day, or roughly nine hours per day, once the five prototypes are flying, the investment firm said. “Six weeks into flight-test, Bombardier has logged only eight flight-test hours, below the [around] 45 we estimate it should have flown by now,” said UBS.

Analysts and reporters pressed Beaudoin on the status of the flight-test program during the teleconference. “The flight-testing is going well so far. It’s been limited because we had planned quite an extensive update period and we’re within weeks of starting to fly the second airplane and then the others will follow,” he said. “We are on plan with the flight-test program at this point. It’s early days; it’s just starting. There’s only one flight-test vehicle in flight, but we are where we thought we would be.”