Stock aircraft is the English-speaking community's term for the aircraft that were included with the installation of the main YSFlight game. They hold both the modeling par and the .dat performance par. Numbering 88 in total, they were all created by Soji Yamakawa.
There have been many packs made by other users that are based around the stock aircraft. One such pack is Taskforce 58 's Stock-bis pack, which repaints, replaces and reshapes all of the stock aircraft, using the original aircraft as a base.