Development of the ARJ21 (Advanced Regional Jet) began in March 2002, the first prototype was rolled out on 21 December 2007, and made its maiden flight on 28 November 2008 from Shanghai. It received its CAAC Type Certification on 30 December 2014 and was introduced on 28 June 2016 by Chengdu Airlines. Resembling the McDonnell Douglas MD-80/MD-90 produced under licence in China, it features a 25° swept, supercritical wing designed by Antonov and twin rear-mounted General Electric CF34 engines. Different sources claim the ARJ21 closely resembles either the McDonnell Douglas MD-80 or the MD-90 which were produced under licence in China. Comac states that the ARJ21 is a completely indigenous design. The ARJ21's development did depend heavily on foreign suppliers, including engines and avionics from the United States. The ARJ21 has a new supercritical wing designed by Ukraine's Antonov Design Bureau with a sweepback of 25 degrees and winglets. Some of China's supercomputers have been used to design parts for ARJ21. Specifications below are for the ARJ21-700 model. For more details of development, design, production and variants, click here.