The development programme was launched in 2008. Production of the prototype began in December 2011, with the first prototype being ready on 2 November 2015 and having its maiden flight on 5 May 2017. Its first commercial deliveries are expected in 2021 to China Eastern Airlines. The aircraft, primarily constructed with aluminium alloys, is to be powered by either CFM International LEAP or ACAE CJ-1000A turbofan engines, and be able to carry 156 to 168 passengers in a normal operating configuration up to 5,555 km (3000 nmi). It is intended to compete primarily with the Boeing 737 MAX and Airbus A320neo. As of 31 August 2018, Comac has 1008 commitments including 305 firm orders, mostly from Chinese leasing companies or airlines. As of 31 August 2018, FlightGlobal recenses 305 orders plus 45 options and 658 letters of intent: 1008 commitments. As of March 2020, China Eastern Airlines subsidiary OTT Airlines is scheduled to be the launch customer for the C919. For details of the development, design and orders for the C919, click here.