After painstakingly acquiring years of practical, hands-on experience in FJ44 Citation re-engining, Sierra has applied their skill to the next logical aircraft - the Citation 550 series. FAA certified in July 2008, the Sierra Super II is a high-performance modification to the Cessna Citation 550 model, featuring new Williams FJ44-3A Wide Sweep 2,820 lb. turbofan engines.
Included in this modification are:
* Digital Channel FADEC for comprehensive power management.
* Full time syncing between the two engines when in ECU mode.
* Airframe modification to accept the new engines:
* All engineered and approved aircraft structural changes to accept the FJ44ís.
* All new engine mounts, hoses and bleed air lines.
* New high recovery inlets and convergent / divergent exhaust nozzles.
* Paint on the affected areas.
The Super II provides superior performance and capability. The Super II provides the following performance benefits over the JT15D-4 engine:
* The JT15D-4 powered aircraft can only maintain Vmo to 19,000 feet where the Super II can maintain Vmo all the way to the Mmo limit and then Mmo as high as 35,000 feet.
* Climb direct to 43,000 feet at gross weight in less than 25 minutes.
* Economy cruise speed as much as 40 knots faster.
* Fly 250 miles farther at maximum cruise power.
* Fly 400 miles farther at economy cruise power.
* Climb more than 50% better at sea level with all engines operative and 38% better at sea level with one engine operative.
* Reduced takeoff distances, particularly at high altitudes and temperatures.