Sierra Industries' tells ANN that their FJ44 Citation II retrofit testing continues, nad boasts an accumulation of more than 14 hours of flying time since their first flight on September 19, 2007.

More than 11 hours in the FJ44-3A powered aircraft, known as the "Sierra Super II", have been conducted in Class A airspace above 25,000 feet and more than 5.5 hours have been in excess of 40,000 feet. Reaching a maximum speed of .705 Mach in straight and level flight at FL430, the Sierra Super II successfully reached the outside corner of the FAA-approved operating envelope.

Sierra test pilots reported several significant performance improvements in the aircraft:

• Maximum Possible True Airspeed (TAS) in any jet aircraft occurs where Vmo and Mmo cross which, in the Model 550, is at 30,500 feet. This speed on an ISA Standard day is 412 knots and was validated in flight test with the actual Sierra Super II aircraft.
• The Sierra Super II will exceed Vmo/Mmo in straight and level flight at maximum weight and ISA at all altitudes up to FL390. It will exceed Mmo at FL430 at weights below 12,000 lbs.
• The theoretical VFR range of the aircraft with reserves (700 lb.) is 2,064 NM. This figure is computed from flight data taken on a cross country test flight October 9.

Details of the October 9 test flight include:

• The Sierra Super II took off with full fuel (5000 lb.), at a takeoff weight of 13,650 lb., a temperature of +26°C (ISA +13°) and climbed direct to FL430 in 24 minutes. The original Pratt-powered aircraft requires 2 hours and 27 minutes to reach this altitude under the same conditions*.
• The Sierra Super II flew 700 NM, landed, and departed again for the 700 NM return flight. Total fuel consumption for the 1400 NM round trip was 3,970 lbs, leaving a reserve of 1,030 lbs. - enough to fly for another 90 minutes at 10,000 ft. and 180 KIAS.
• The Sierra Super II is more than 50 knots faster than the original Citation II at roughly the same fuel flow (see table below). Efficiency at FL430 is 16% better, resulting in a significant increase in range at maximum high speed cruise.
• The Sierra Super II is even faster (3 to 7 kts) than the Citation V at FL430 with the same fuel and payload weight. At the same conditions, the Sierra Super II is 31% more fuel efficient than the Citation V*.

* all Citation II and V performance with Pratt motors taken from manufacturers Operating Manuals.

Sierra Super II Performance at FL430:

'Sierra Super II' FAA certification is expected by the end of the year. The Sierra Super II modification provides significant across-the-board performance enhancement to the Citation II - boosting fuel efficiency as much as 25%, cutting time-to-climb to under 25 minutes to FL430, extending range to 1775 NM, and more than doubling maximum fuel payload. Dramatic reductions in takeoff field length (more than 20% reduction at 5000 ft., ISA +20º), coupled with increased climb rates 'make the Sierra Super II a superb all-around performer for virtually any field conditions or altitude.'

2007 pricing for the complete Sierra Super II modification starts at $1.929 million (with trade-in credit for existing engines) and includes Williams FJ44-3A engines and installation, all associated structural changes to accommodate the increased thrust, all necessary hydraulic, mechanical and electrical changes and dual-channel FADEC for power management and full-time synchronizing between engines.

FMI: www.sijet.com