redesigned, and nacelle fairings were added. Fuel capacity was increased by . The result of the improvements was a cruise speed of — exceeding 400 kn, felt to be an important marketing benchmark by Cessna — and a range of with a 45-minute fuel reserve. The improved JT15D-4B engines had higher temperature-rated components, allowing more thrust at higher altitudes. The S/II replaced the II from 1984, but some potential buyers objected to the sharp price increase from for the II to for the S/II, prompting Cessna to reintroduce the II in late 1985; both were built until the Bravo introduction. Deliveries of the S/II amounted to 160, including fifteen T-47A aircraft purchased by the U.S. Navy. The S/II's higher performance coupled with its lower production numbers led to substantially higher demand on the used aircraft market compared to the standard II and II/SP. Government variants The US Customs & Border Protection purchased ten Citation IIs configured with fire control radar (initially the F-16's AN/APG-66(V), later the Selex ES Vixen 500E system) and the WF-360TL imaging system. These aircraft have been used effectively in Panama, Honduras, Colombia, Peru, Venezuela, Mexico and Aruba. The similar OT-47B aircraft are based on the Cessna Citation V airframe. The T-47A was a modified version of the Citation S/II (Model 552) for the U.S. Navy, featuring a wingspan reduction and hydraulically boosted ailerons for enhanced maneuverability, thrust JT15D-5 engines, a cockpit roof window for better pilot visibility during hard maneuvering, strengthened windshields for protection against bird strikes during high-speed low-altitude sorties, multiple radar consoles, and the AN/APQ-167 radar system. Intended to replace the North American T-39D as a radar systems trainer aircraft, fifteen aircraft were purchased in 1984 to train naval radar intercept officers. All T-47A aircraft were operated with civil aircraft registration numbers by Training Air Squadron VT-86 based at Naval Air Station Pensacola, Florida. On 20 July 1993, thirteen of the fifteen aircraft were destroyed when a roofing contractor accidentally set fire to a hangar at Forbes Field where the aircraft were being stored by Cessna. The navy replaced the lost trainers with upgraded T-39D aircraft and the two survivors were transferred to civil owners. Citation Bravo The Citation Bravo first flew on April 25, 1995, was granted certification in August 1996, and was first delivered in February 1997. It features new P&WC PW530A turbofans, modern Honeywell Primus EFIS avionics, a revised Citation Ultra