Story ID: 
Alaska company developing TPE-powered Caravan
By: Gordon Gilbert
Caption: A more powerful, better-performing Cessna Caravan 208, including improved fuel burn, is the object of a program by Anchorage, Alaska-based Caravan dealer, 
Word Count: 313
A more powerful, better-performing Cessna Caravan 208, including improved fuel burn, is the object of a program by Anchorage, Alaska-based Caravan dealer, modifier and maintenance facility Aero Twin to convert the turboprop single from its original 675-shp Pratt & Whitney Canada PT6 to the 850-shp Honeywell TPE331-12JR-701S.Aero Twin, which has spent the last 18 months developing the “850 Caravan” and expects to receive an STC for the conversion next spring, first flew a prototype of the airplane on October 2. The company said preliminary performance improvements include a takeoff distance of 1,000 ft (on wheels) and an initial rate of climb of 2,000 fpm. The water takeoff run for the TPE-powered Caravan amphibian is 14 sec (compared with 30- to 40-sec runs by the P&WC-powered Caravan) and the initial climb rate 1,300 fpm, according to Aero Twin president Tony Cestnik. TBO of the 850 Caravan’s Honeywell engine is 7,000 hr for “qualified commercial operators–nearly double the current 3,600 hr.”Although installation of the TPE331 adds 120 lb to the airplane’s empty weight, Cestnik expects that operators will see at least a 12 pph decrease in fuel burn since the TPE331 is more efficient. “The Caravan is a fantastic airplane,” Cestnik said, “We’ve just helped it to the next level of refinement.”The approximately $600,000 installed price includes a four-blade Hartzell propeller (replacing the three-blade McCauley) with automatic drag reduction; auto-ignition system; “completely” new instrumentation; and fewer engine controls (a power lever and prop condition lever). The original engine and prop are returned to the customer. In addition to Honeywell and Hartzell, other key suppliers involved in the conversion include Lord, Kelley Aerospace and APC Components.Downtime is estimated at 30 days. At least four U.S. service facilities will be designated by Aero Twin as 850 Caravan installation centers. Customer deliveries are scheduled to start next July. A TPE331 conversion program for the Caravan 208B is planned as well.