The Citation S550-based Sierra Super S-II completed a 36-minute maiden flight September 26 at Sierra’s Uvalde, Texas modification center. The flight demonstrated the “dramatic” improvements of the dual fadec-controlled Williams FJ44-3A engines, the company said.
The aircraft reached 18,000 feet in three minutes and 45 seconds. Sierra CEO and chief test pilot Mark Huffstutler performed a variety of in-flight system checks, including shutdown and restart of each engine, stalls and pressurization checks. “This was a superb first flight,” Huffstutler said. “Everything worked so well, it seemed almost routine. There is no substitute for sheer power–just what this aircraft needed to achieve its full potential.”
A second flight on October 1 lasted 2.9 hours and achieved a 43,000-foot cruising altitude and 400-knot true airspeed. The company said the modified Super S-II demonstrated “surprisingly low fuel consumption.” The aircraft landed with fuel tanks still more than half full.
The FJ44-powered Super S-II “provides a stunning improvement in across-the-board performance,” the company said. Sierra plans to begin flight testing following the airplane’s return from the convention this week. It is currently on display at the Orlando Executive Airport.