CFM International Executive VP Chaker Chahrour has told Commercial Aircraft Corp. of China (COMAC) “they need more experienced program management” on the 150-seat C919 aircraft, whose first flight has now slipped from this year to 2015.

Despite the slip, CFM has left the test schedule unchanged for the LEAP-1C engine that will power that aircraft.

“Building an aircraft is not an easy task,” Chahrour told reporters during a briefing at the Singapore Airshow. “They have some difficulty with some suppliers and in bringing them all together at the same time.”

Chahrour, who is CFMI’s direct liaison with COMAC, is confident that the C919 will “be flying sometime in 2015.” Describing the relationship between the GE Aviation/Snecma joint venture engine company and the Chinese aircraft manufacturer as “great,” he added the relationship is of “a different texture than what we’ve got with the two experienced airframers, Boeing and Airbus, but we work well together.”

The LEAP-1A engine is an option on the Airbus A320neo and the LEAP-1B is the sole powerplant on the Boeing 737 MAX program. “You have to work (the C919) program with a different mindset than you do with Boeing and Airbus because of the different level of experience,” Chahrour said.

“COMAC is a young civil aircraft manufacturer,” a COMAC representative told Aviation Week. “But the management capabilities, including suppliers’ management, are improving. The cooperation between COMAC and CFMI is smooth and friendly.”

Asked whether FAA would follow CAAC when, as is expected, the Chinese regulator certifies the aircraft, Chahrour acknowledged, “It’s not smooth sailing between CAAC and FAA in terms of when they’ll come together to certify the plane. I think eventually they’ll get there...It won’t be easy, but they’ll get there.”

COMAC holds 380 orders for the C919, mainly from Chinese airlines. Chahrour said that CFMI is confident Western airlines will eventually order the C919, but “it is going to require a significant amount of domestic flying” in China before they are convinced. He added, “Chinese airlines are sophisticated. They’re not going to fly an aircraft they’re not comfortable with.”

Though CFMI is not delaying the LEAP-1C program—which will be the first of the LEAP engines to be tested on a flying test bed—it will reconsider if there is another delay. “If the flight test (program) is going to slip (again), we obviously have to go back and look at the need and timing to build (flight test) compliance engines,” Chahrour said. “We don’t want to build engines and leave them in the inventory.”

Overall, CFMI is bullish on the Chinese market. “China is a huge player for us,” Chahrour noted. “It’s going to be a huge year for (commercial aircraft sales in) China. Perhaps 800-1,000 airplanes (will be ordered by Chinese carriers in 2014, of which 80% will be narrowbodies), so we’ll spend a lot of time in China this year.”