The Cessna Citation II are light corporate jets built by Cessna as part of the Citation family. Stretched from the Citation I, the Model 550 was announced in September 1976, first flew on January 31, 1977, and was certified in March 1978. The II/SP is a single pilot version, the improved S/II first flew on February 14, 1984 and the Citation Bravo, a stretched S/II with new avionics and more powerful P&WC PW530A turbofans, first flew on April 25, 1995. The United States Navy adopted a version of the S/II as the T-47A. Production ceased in 2006 after of all variants were delivered. Design and development The Citation II (Model 550) was developed to provide the same docile low-speed handling and good short-field performance as the preceding Citation I while addressing a primary criticism of that aircraft — its relatively slow cruise speed of around at altitude. The II stretches the Citation I fuselage by 1.14m (3 ft 9in), increasing seating capacity to ten (two pilots and eight passengers) and gross weight to . Wingspan was increased by , fuel capacity was increased from to , and more powerful, Pratt & Whitney Canada JT15D-4 engines were installed for a higher cruise speed of and a longer range of . The cabin interior was also redesigned to increase headroom by . The stretched Citation was announced in September 1976, it first flew on January 31 1977 and FAA certification was awarded in March 1978. The II/SP (Model 551) is the single pilot version, type certificated to slightly less stringent FAR Part 23 standards, with a slightly reduced maximum takeoff weight (MTOW) at and minor changes in cockpit equipment. As the II and II/SP are otherwise largely similar, the reduction in MTOW of the II/SP often mandates operating with a reduced fuel load, shortening the aircraft's loaded range compared to the standard II. Both the II and II/SP require special training to be operated by a single pilot. A total of 688 II and II/SP aircraft were delivered. Citation S/II The improved Citation S/II (Model S550) was announced in October 1983 and first flew on February 14, 1984, before certification in July. It gained a supercritical airfoil with swept wing roots, aileron and flap gap seals, and a fluid deicing system instead of the pneumatic deicing boots used on earlier Citations. To further reduce drag, the fuselage and engine nacelle pylons were