China may not be able to fully meet its deadline in developing its C919 single-aisle commercial aircraft , as progress has been slow in the assembly lines than previously thought. In fact, engineers are now five years behind schedule.
Based on information from sources with direct knowledge of the program, as revealed to Reuters, the government-controlled Commercial Aircraft Corporation has been hounded by a host of technical glitches that have severely affected test flights.
Technical issues are common stuff in the aircraft business, but the turtle-pace in development could be a slap in the face for China, which for years has poured tons of cash in its first serious attempt to compete with the world's biggest jet-makers: Boeing and Airbus.
China's latest dilemma was traced down from a mathematical blunder, the sources disclosed. COMAC engineers miscalculated the forces that would be imposed on the twin engines of the aircraft in flight, referred to as "loads in the industry", and sent inaccurate data to the engine manufacturer, CFM International, sources said.
The result: both the engine and its casing may need to be strengthened, most likely at the expense of COMAC, although any modification was denied by another source, reports revealed.
That and other technological and structural problems meant that by early December, after more than two and a half years of flight testing, COMAC had completed less than one-fifth of the 4,200 hours in the air that the Civil Aviation Administration of China required for final approval, sources told Reuters.
COMAC, which has essentially secretly designed the C919 since 2008, seldom makes public its aims. A company executive, Yang Yang, disclosed to Chinese state media recently that in two to three years he expected China's regulators to certify him without giving any further details.
The publicly stated target of the company was around end of 2020. Other COMAC officials said they plan to be accredited and completed by 2021. The required calculations and data to be sent to the engine manufacturer have not yet been finalized by COMAC.
Meanwhile, given the uncertainty, there is no assurance that COMAC will reach the 2021-2022 goal of Yang, Reuters reported, as per sources' information.
The engine miscalculation does not reflect a lack of theoretical understanding - China has been putting people in space for almost 20 years. But it does underscore the national aerospace manufacturer's lack of expertise in designing and building commercial aircraft.