In the early 1980s, the US Navy decided to replace the fleet of aging North American Rockwell T-39D aircraft it had been using to train navigators and Radar Intercept Officers (RIOs) in its Undergraduate Naval Flight Officer (UNFO) program. RIOs were the officers who rode in the back seats in aircraft like the Northrop Grumman F-14 Tomcat, operating the radar and providing target intercept guidance to the pilot. Following a competitive procurement process, the Navy awarded Cessna Aircraft a contract for 15 modified Citation S/II aircraft in 1984. Cessna called the new version the Model 552, and the Navy designated it the T-47A.
The primary differences between the basic Citation S/II and the T-47A were:
More powerful Pratt & Whitney of Canada JT15D-5 turbofan engines to replace the S/II's JT15D-4B engines.
Reduced wingspan from the S/II's 52.2-foot span to 46.5 feet on the T-47A.
Increased fuselage length from 47.2 feet on the S/II to 47.9 feet on the T-47A—necessary to accommodate the nose-mounted Emerson APQ-159 radar.
Addition of three student radar stations in the main cabin to replace the S/II's executive seating.
The combination of more powerful engines and a shorter wingspan provided better acceleration, an improved rate of climb, and a higher top speed. The basic Citation S/II was…
