While the Commercial Aircraft Corporation of China Ltd.  prepares to fly an additional two C919 prototypes this year, a shifting timeline is threatening its ability to advance its standing among the world’s established aerospace companies, AINonline.com reported.

According to a company statement, all of its prototypes will undergo more than 1,000 flight-test items over the next two years, which could potentially push its earlier target of 2020-2021 into 2022.

Chinese media outlets say manufacturing will commence later this year while plans call for airworthiness certification and aircraft deliveries to China Eastern Airlines in two to three years. COMAC said “scientific research and production work” continues to progress in an “orderly manner.”

Coded 105 and 106, the two jets have entered final assembly at the company’s Shanghai production facility. Once complete, the prototypes will join the flight-test program, bringing the total number of C919s to six.

According to the report, the first prototype, 101, completed its long-delayed first flight in May 2017 followed by a long-distance test flight six months later. Aircraft 102 conducted a successful two-hour first flight in December of that year and both prototypes flew again in June 2018 as part of a control-stability test and systems check. Prototype 103 completed its inaugural flight last December.

Meanwhile, aircraft 104 performed a one-hour and 25-minute first flight in August before later transferring to Dongying Shengli Airport in east China’s Shandong Province. All four prototypes are undergoing flight, static, and other ground verifications tests in Xi’an, Shaanxi province, Nanchang in Jiangxi province, and Shandong’s Dongying.

COMAC took the opportunity to debut its C919 flight simulator along with a 1:15 ratio mockup of its ambitious Chinese-Russian CR929 widebody at the 18th Aviation Expo/China, held from September 18-20. The Chinese airframer confirmed that while it had drawn a conceptual design draft, program managers remained in the process of selecting and concluding agreements with system and equipment vendors, the report said.

The general director of Russian CR929 partner United Aircraft Corporation, Yury Slyusar, met with Rolls-Royce and GE executives in late August at the MAKS 2019 airshow outside Moscow to talk over Western powerplant alternatives for the joint Russian-Chinese widebody project known as the Craic CR929.

The CR929 chief designer from the Russian side of the program, Maxim Litvinov, told AIN at the show that a Western engine choice could come as soon as the second half of next year, when Craic expects to begin naming the various systems suppliers. A second engine alternative—to involve a Sino-Russian partnership — will take somewhat longer to define, he added.

According to Simple Flying, the C919 was designed to combat the stranglehold that Boeing and Airbus have on the narrow body jet market.

COMAC engineers were re-evaluating the C919’s flight-deck design to satisfy Part 25.1302 of the Federal Aviation Regulations (FAR). Credit: Skyscrapercity.com.

Specifications suggest that the plane will hold between 158 and 168 passengers, and will have a range of just over 4,000 km up to 5,555 km.

Already the C919 has received a total of 815 orders from 28 different customers, mostly based in China. However, many of these orders are thought to be LOI (Letter of intent) or MoUs (Memorandum of understanding) rather than firm orders. Aside from leasing companies, carriers who have ordered the plane include Hainan, Air China, China Eastern and China Southern.

It was reported by AINonline.com in October of last year, that COMAC was struggling to bring the project in line with US Federal Aviation Administration requirements.

According to a source working closely with COMAC engineers were re-evaluating the C919’s flight-deck design to satisfy Part 25.1302 of the Federal Aviation Regulations (FAR).

“Section 1302 is quite strict on human factors and necessary for FAA certification, but it’s not required by the CAAC,’’ he told AINonline.com. ”So now there is a conflict between whether they have to meet 1302 requirements or not. If COMAC wants to sell aircraft outside of China … there is always the constant debate of how much of the requirements they need to comply with, coupled with how many design changes are necessary and how much money needs to be spent.’’

Also, sources said one of the  long-standing impediments constraining progress is the integration of avionics components and its subsystems in the flight deck. This challenge reflects a larger concern about the company’s ability to achieve effective coordination across component teams.

Unlike the ARJ-21, which uses commercial-off-the-shelf products in the cockpit, the C919 is working with a complete avionics system design with key components sourced from western suppliers.

“It’s not like you are working with Airbus or Boeing who can go through this process within an 18-month time span. You need to account for the learning curve.’’