MOSCOW and BEIJING—China increasingly looks like it is taking a leading role in a politically driven widebody aircraft program defined in 2016 as an equal partnership between Moscow and Beijing.

Launch of full-scale development of the aircraft, comparable with the Airbus A330-900, has slipped by a few months. Four months ago it was due in the last quarter of 2016 or the first quarter of 2017, which is almost over. Registration of a joint program company owned by Comac and United Aircraft Corp. (UAC) will mark the launch.

General Electric and Rolls-Royce will compete to supply a Western engine with which the widebody airfract will enter service around 2027. The Chinese side is reportedly pushing to develop the intended second type of engine for the aircraft, the Long-Range Wide Body Commercial Aircraft (LRWBCA).

The balance of top appointments is one indication of the program’s tilt toward China. Guo Bozhi, head of Comac’s widebody aircraft department, will be the overall project leader. Specifically, guo will be president of the joint company, which will design, sell and support the LRWBCA. Sergey Fominykh, UAC’s head of widebody aircraft programs, will be only a member of the board of directors.

Shanghai, Comac’s hometown, has been chosen as the location for the headquarters of the project company. That was to be partly balanced by setting up the joint engineering center in Moscow. But it has been decided that the office, responsible for top-level development, will also be in Shanghai, an industry source said. The engineers will spend some months each year in Moscow.

A Western engine is needed at first. In 2016, the Russian side expected to offer an engine, the forthcoming PD-35 of United Engine Corp., as an alternative around 2030. The Chinese are pushing to substitute their proposed engine, the CJ2000, Russia’s Life news service reported. The Chinese ambition to do so is not surprising—and also implausible, since China has very little experience in developing any kind of aircraft engine, let alone a turbofan of probably more than 70,000 lb. thrust, which the LRWBCA will need.

Another sign of imbalance is that Comac is to build the LRWBCA’s metal-and-composite fuselage, while UAC will make the composite wing. In both cases, that work will presumably include detail design and development. Comac will also perform final assembly, the stage of aircraft manufacturing that brings the most glory. The wing of an airliner usually accounts for rather less than half of the cost, even if the center wing box is included.

Discussing how to balance that up, perhaps by allocating a preponderant share of onboard equipment, may be a reason for the delay in getting the program moving. The Chinese negotiators must have heft in these talks because they probably have easier access to government funds than UAC has and because China, with its greater population and larger economy, will offer a much bigger home market.

UAC’s announcement of the leadership appointments at least clears one obstacle to registering the joint company—in Shanghai. This will happen soon, a spokesperson for UAC says. The intended name is China-Russia Commercial Aircraft International Corp. Ltd., a good sign of its governmental origins.

If the launch delay does not affect the schedule, a request for proposals for engines should be issued in September, says the industry source. Six months later will come the request for proposals for onboard equipment. At this preliminary stage, Comac is leaning toward General Electric, its partner on the ARJ21 and C919, says the source, while UAC prefers Rolls-Royce.

While maximizing its influence in the LRWBCA program, Comac would prefer to develop its own widebody, which it had penciled in for the 2020s before the top leadership of China and Russia decided, evidently for diplomatic reasons, that the two countries should work together.

The LRWBCA will be able to carry about 280 passengers over 12,000 km (7,500 mi.) in its basic configuration.

UAC has a fallback option in case the LRWBCA hits major troubles. The Russian company has begun work on a modernized Ilyushin Il-96 based on the current-production Il-96-400, a stretched freight version. Preliminary work is also underway on a two-engine airliner based on the Il-96. It would use the PD-35, development of which began in 2016.