Sierra Industries of Uvalde, Texas, has earned a supplemental type certificate (STC) to install Williams International FJ44-3A engines on Cessna Citation 550 (Citation II) twinjets.
The FJ44-3As, with 2,820 pounds of thrust, will transform Citation IIs into 404-knot airplanes with maximum ranges of 1,800 nm. Standard Citation IIs use 2,500-lbst Pratt & Whitney JT15D-4 engines and have max cruise speeds and ranges in the neighborhood of 360 kt and 1,600 nm, respectively.
Sierra says that their Super IIs will climb to FL430 in “under 25 minutes,” that there is a 20-percent reduction in takeoff length at 5,000 feet/ISA +20-degree conditions, and that there is an increase in max fuel payload.
In adddition, Sierra says that Super IIs will have improved fuel efficiency and reduced carbon emissions with the Williams engines. So far, Sierra has garnered orders for six Super II conversions.
For Citation IIs with thrust reversers, the price of the conversion is set at $1.929 million. A new price structure is to be announced at this year’s upcoming National Business Aviation Administration convention.