Comac plans upgrades for the C919 airliner, including increased cabin luggage space, to compete with Boeing and Airbus.

China’s flagship civilian aircraft maker is planning to upgrade the cabin capacity of its C919 narrowbody airliner to improve passenger experience and boost the plane’s chances of challenging the Boeing-Airbus duopoly, a source with knowledge of the plans said. Bigger overhead luggage compartments and drip-proof air conditioning outlets are among the design upgrades being sketched out by the Commercial Aircraft Corporation of China (Comac). “Comac has realised it must make passengers as...