Also known as the model CE-S550, the Citation S/II, or Super II, is a light twin-engine business jet, manufactured by Cessna Aircraft Company, based in Wichita, Kansas. The Citation S/II is an improved version of the popular Citation II, with more powerful Pratt & Whitney Canada JT15D4Bs turbofans. The Citation S/II incorporated a number of aerodynamics improvements, especially the new wing design developed for the Citation III. The Citation S/II can be flown by a single pilot and can be configured for up to 10 passengers. The Citation S/II has faster speed and increased payload capability over its predecessors, and stands out by its simplicity, flexibility and economy. The Citation S/II replaced the Citation II in the product line in 1984, but, the Citation II was returned to production the late 1985 due to market demands, and both were produced side-by-side until replaced by the Citation Bravo.