PT6 | |
---|---|
A PT6A-20 on display at the Canada Aviation and Space Museum | |
Type | Turboprop / turboshaft |
National origin | Canada |
Manufacturer | Pratt & Whitney Canada |
First run | 1960 |
Major applications |
Beechcraft Super King Air de Havilland Canada DHC-6 Twin Otter Pilatus PC-12 Sikorsky S-76 |
Number built | 51 thousand (as of November 2015) |
Unit cost | PT6A-60A: $955,000; PT6A-68: $855,000 |
Variants | Pratt & Whitney Canada PT6T |
The Pratt & Whitney Canada PT6, produced by Pratt & Whitney Canada, is one of the most popular turboprop aircraft engines in history. The PT6 family is known for its reliability with an in-flight shutdown rate of 1 per 333000 hours since 1963, 1 per 651,126 hours over 12 months in 2016.Time between overhauls are between 3600 and 9000 hours and hot section inspections between 1800 and 2000 hrs.
In US military use, they are designated as T74 or T101. The main variant, the PT6A, is available in a wide variety of models, covering the power range between 580 and 920 shaft horsepower in the original series, and up to 1,940 shp (1,450 kW) in the "large" lines. The PT6B and PT6C are turboshaft variants for helicopters.
In 1956, PWC's President, Ronald Riley, foreseeing the need for engines with much higher power-to-weight ratio, ordered engineering manager Dick Guthrie to establish a development group to create a turboprop engine designed to replace piston engines. Demand for the Wasp radial engine was still strong and its production line's output was robust and profitable. Riley gave Guthrie a modest budget of C$100,000. Guthrie recruited young engineers from the National Research Council in Ottawa and from Orenda Engines in Ontario. In 1958, the group began development of a turboprop engine intended to deliver 450 shaft horsepower. The first engine was powered up and run successfully in February 1960. It first flew on 30 May 1961, mounted on a Beech 18 aircraft at de Havilland Canada's Downsview, Ontario facility. Full-scale production started in 1963, entering service the next year. By the 40th anniversary of its maiden flight in 2001, over 36,000 PT6As had been delivered, not including the other versions. The engine is used in over 100 different applications.