Standard, Stevens Offer King Air 200 PT6-42 Upgrade

An STC to upgrade King Air 200s to Pratt & Whitney Canada PT6-42 power is no longer a conversion program in waiting. Engine overhauler Standard Aero (Booth 5700) and aircraft modifier Stevens Aviation (Booth 8192) have disclosed a collaboration to offer P&WC PT6-42 conversions for King Air 200s powered by the -41. The conversion provides the KA200 with higher cruise speeds and altitudes, and eliminates hot-day takeoff restrictions.

Stevens developed the STC in the early 1990s, but when the company was ready to offer the conversion a few years later, the general aviation market was starting its present upswing and P&WC didn't have -42 engines to spare for mod programs, according to Stevens CEO Kurt Herwald. Thus it was left to Standard Aero to come along with an upgrade to turn -41s into -42s during regular overhauls or repairs.

The modification permits the gas generator to provide increased thermodynamic reserve-in other words, the engine can run 50 degrees hotter. The maximum operating temperature of -42 is 800°C compared to 750°C on a -41.

Whayne Supply of Louisville, KY, was the first operator to receive the conversion. "We can now fly up to 20 knots faster cruise speed, 4,000 feet higher and are no longer temperature-limited on takeoff on a hot day," said flight operations manager Jim Girdley. There is no difference in shp between the -41 and -42, no impact on weight, noise or fuel consumption as a result of the conversion.

Standard Aero can do the conversion at its facilities in Winnipeg, Canada, or Charlotte, NC, for "under $100,000" when performed at the time of an overhaul or repair, said Ed Richmond, executive director of PT6 programs. Conversion time is 35 days when done in conjunction with an overhaul, or 15 days if done during a repair.

There are currently some 800 -41 powered KA200s in service.

By Gordon A. Gilbert