Comac unveiled two variants of its single-aisle C919 jet at an airshow in Shanghai last week, according to people familiar with the matter, as the Chinese planemaker looks to broaden the model’s reach to more customers.

Commercial Aircraft Corp of China Ltd., as Comac is officially known, displayed a jet capable of carrying 210 passengers in a two-class configuration, and a smaller version tailored for high-altitude airports, the people said.

The larger version is similar to Airbus SE’s A321 and not yet close to entering production as it is a development concept, one of the people said, declining to be identified discussing private information. The plane would need higher performance engines and could be designated “LR” for long range, the person added.

The so-called plateau variant for smaller high-altitude airports would seat 140 passengers. It is also in the concept phase of development, the person said.

A representative for Comac didn’t respond to requests for comment.

Comac Chairman He Dongfeng said in September the follow-up development of the C919 would include stretched and shortened versions, local outlet Securities Daily reported at the time.

The state-owned manufacturer has delivered only two C919s to launch customer China Eastern Airlines Corp., though the Shanghai-based carrier topped up its commitment with an order for 100 more C919s in September.

Comac started developing the plane in 2008 and production began in late 2011. It only received official certification to fly in September 2022, paving the way for deliveries to start.