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31-472: Basler Turbo Conversions was founded in 1990 solely focused on converting existing C-47/DC-3 airframes into the BT-67. Basler configures each new build to the client's specifications. Industries served include cargo, military, cloudseeding, and scientific research. The conversion includes fitting the airframe with new Pratt & Whitney Canada PT6A-67R turboprop engines, lengthening the fuselage , strengthening

62-410: A free power turbine . The starter has to accelerate only the gas generator, making the engine easy to start, particularly in cold weather. Air enters the gas-generator through an inlet screen into the low-pressure axial compressor . This has three stages on small and medium versions of the engine and four stages on large versions. The air then flows into a single-stage centrifugal compressor , through

93-529: A PT6 and propeller flying test-bed until it was replaced with a Beech King Air in 1980. The King Air test-engine or propeller replaced one of the standard ones. In 1974 the Beech 18 had been unable to fly fast enough and high enough to test the PT6A-50 for the de Havilland Canada Dash 7 so a Vickers Viscount was modified as a PT6 test-bed with a Dash-7 installation in the nose. The first production PT6 model,

124-433: A bleed arrangement which reuses the bleed air by returning it in a tangential direction at the entry to the compressor, an idea patented by Schaum et al. and titled "Turbine Engine With Induced Pre-Swirl at Compressor Inlet". It acts like a variable vane and is known as a "Jet-Flap". All versions of the engine consist of two sections that can be easily separated for maintenance: a gas generator supplies hot pressurized gas to

155-408: A folded annular combustion chamber , and finally through a single-stage turbine that powers the compressors at about 45,000 rpm. Hot gas from the gas generator flows into the power turbine, which turns at about 30,000 rpm. It has one stage on the small engines and two stages on the medium and large ones. For turboprop use, this powers a two-stage planetary output reduction gearbox, which turns

186-577: A possible new market such as a Super PC-12, a more powerful TBM, or a bigger King Air. When de Havilland Canada asked for a much larger engine for the DHC-8 , roughly twice the power of the Large PT6, Pratt & Whitney Canada responded with a new design initially known as the PT7, later renamed Pratt & Whitney Canada PW100 . The rate at which parts deteriorate in a gas turbine is unbalanced insofar as

217-581: A proposed 2,000 shp (1,500 kW) engine to replace the most powerful versions of the PT6. It was considered likely to be a development of the PT6C core, and would fit between the 1,750 shp (1,300 kW) PT6C-67C/E and the 2,300 shp (1,700 kW) PW100 family. It was expected to be ready to launch by the end of 2017 for an initial helicopter platform with a 10-15% reduction in brake specific fuel consumption . This 2,000 hp engine would target

248-725: A small gas turbine engine. Demand for the Wasp radial engine was still strong and its production was profitable but the aim was to become Canada's prime engine company by focusing on a small gas turbine engine. Riley gave Guthrie a modest budget of C$ 100,000. Guthrie recruited twelve engineers with experience gained at various places including the National Research Council in Ottawa , Orenda Engines in Ontario , Bristol Aero Engines and Blackburn Aircraft . They completed

279-476: Is a turboprop aircraft engine produced by Pratt & Whitney Canada . Its design was started in 1958, it first ran in February 1960, first flew on 30 May 1961, entered service in 1964, and has been continuously updated since. The PT6 consists of two basic sections: a gas generator with accessory gearbox, and a free-power turbine with reduction gearbox. In aircraft, the engine is often mounted "backwards," with

310-768: Is a small turbojet engine. The Pratt & Whitney T73 (Pratt & Whitney JFTD12) is a related turboshaft engine. The J60 conception and project design began in July 1957 at United Aircraft of Canada (now Pratt & Whitney Canada ) in Montreal . The project design details were transferred to the main P&;W company in East Hartford and in May 1958, the first prototype, with military designation YJ60-P-1 commenced testing. Flight tests were completed in early 1959; followed by

341-561: Is known for its reliability with an in-flight shutdown rate of 1 per 333,333 hours up to October 2003, 1 per 127,560 hours in 2005 in Canada, 1 per 333,000 hours from 1963 to 2016, 1 per 651,126 hours over 12 months in 2016. Time between overhauls is between 3,600 and 9,000 hours and hot-section inspections between 1,800 and 2,000 hours. Early PT6 versions lacked a FADEC , autothrottle could be installed as an aftermarket upgrade with an actuator , initially for single-engine aircraft like

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372-478: Is known for its reliability, with an in-flight shutdown rate of 1 per 651,126 hours in 2016. The PT6A turboprop engine covers the power range between 580 and 1,940 shp (430 and 1,450 kW), while the PT6B/C are turboshaft variants for helicopters. In 1956, Pratt & Whitney Canada's (PWC) president, Ronald Riley, ordered engineering manager Dick Guthrie to hire a team of gas turbine specialists to design

403-578: Is the same as in 1964, updates have included a cooled first-stage turbine vane, additional compressor and turbine stages and single-crystal turbine blades in the early 1990s. Its pressure ratio is 13:1 in the AgustaWestland AW609 tiltrotor, the highest that can be used without cooled turbine blades. In response to the General Electric GE93 , in 2017 Pratt & Whitney Canada started testing core technology and systems for

434-615: The Argentinian Air Force with an est. cost of $ 143 million, with the main contractor being Basler Turbo Conversions . As of 2019, a total of 15 BT-67 aircraft have been involved in crashes or other incidents since the 1990s. Data from Born Again Basler and Jane's Civil and Military Aircraft Upgrades 1994–95 General characteristics Performance Related development Related lists Pratt %26 Whitney Canada PT6 The Pratt & Whitney Canada PT6

465-625: The PC-12 and potentially in twin-turboprop aircraft. In October 2019 the PT6 E-Series was launched on the PC-12 NGX, the first general aviation turboprop with an electronic propeller and engine control system with a single lever and better monitoring for longer maintenance intervals, increased from 300 to 600 hours, and a TBO increased by 43% to 5,000 hours, reducing engine operating costs by at least 15%. In April 2022, Daher announced that

496-435: The airframe , upgrading the avionics , and making modifications to the wing leading edges and wingtips . Due to the higher fuel consumption of the turbine engines of the BT-67, compared to the original piston designs fitted to the standard DC-3, range on the standard fuel tank, with 45 minute reserve, is reduced from 1,160 to 950 nautical miles (2,150 to 1,760 km). Basler provides a long-range fuel tank which increases

527-524: The PT6 have appeared over time: The PT6A family is a series of free-turbine turboprop engines providing 500 to 1,940 shaft horsepower (370 to 1,450 kilowatts) BX Turbo de Havilland Canada Beaver DHC-2 (STC) ARON M80 (WIG CRAFT) Piper PA-46 (M700 Fury) The engine is used in over 100 different applications. Data from Jane's 62-63, Related development Comparable engines Related lists Pratt %26 Whitney JT12 The Pratt & Whitney JT12 (US military designation J60 )

558-467: The PT6, which first ran in December 1963, was beset with engineering problems, cost overruns and lack of sales. It was almost cancelled. The team lacked the ability to deal with the technical difficulties, i.e. how to develop the engine, because, as one of the team Elvie Smith recalled, they came from research and design backgrounds. They learned how to run a development program, such as testing around

589-458: The PT6A-20, was the pipe diffuser patented by Vrana, another of the original PT6 team. It replaced the vaned type diffuser used in centrifugal compressors. The pipe diffuser became standard design practice for P&WC. Another design change improved the part-speed functioning of the compressor. It is common to bleed air from a compressor to make it work properly at low engine speeds. The PT6 has

620-683: The PT6A-6, was certificated in December 1963. The first application was the Beech Queen Air , enticing the U.S. Army to buy a fleet of the U-21 Ute variant. This helped launch the King Air with Beechcraft selling about 7,000 by 2012. From 1963 to 2016 power-to-weight ratio was improved by 50%, brake specific fuel consumption by 20% and overall pressure ratio reached 14:1. Its development continues and while today its basic configuration

651-565: The aircraft range to 2,140 nmi (3,960 km). The Basler BT-67 has a gunship version used by the Colombian Aerospace Force as of 2017 for counterinsurgency operations . The Colombian gunships are equipped with a forward-looking infrared (FLIR) ball, enabling the aircraft to conduct effective nighttime missions. On 18 April 2024, the State Department approved a possible sale of BT-67s intended for

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682-460: The clock rather than on one shift, from a PWA team which directed the development for several months. The PT6 first flew on 30 May 1961, mounted as a third engine in the nose of a Beech 18 aircraft which had been converted by de Havilland at its Downsview facility in North York, Ontario . Full-scale production started in 1963, with service entry the following year. The Beech 18 continued as

713-714: The compressor intake by inertial separators in the inlet. In some installation such as the PT6A-66B version in the Piaggio P.180 Avanti , the engine is reversed, with the propeller acting as a "pusher", the accessory gearbox facing the front of the aircraft. By the 40th anniversary of its maiden flight in 2001, over 36,000 PT6As had been delivered, not including the other versions. Up to October 2003, 31,606 delivered engines have flown more than 252 million hours. Till November 2015, 51,000 have been produced. The family logged 400 million flight hours from 1963 to 2016. The PT6 family

744-480: The delivery of the new JT12A-5 engines in July 1959. These were for the two Canadair CL-41 prototype trainers with a rating of 12.9 kN (2,900 lb st). The modified JT12A-3 turbojets with a basic rating of 14.69 kN (3,300 lb st) were tested in the two Lockheed XV-4A Hummingbird VTOL research aircraft. The next version, JT12A-21, had an afterburner which delivered a maximum thrust of 17.91 kN (4,025 lb st). Data from Aircraft engines of

775-515: The detailed design of an engine for Canadair's small jet trainer, the CL-41 . It was a 3,000-pound-force (13 kN) thrust turbojet but the design was taken over by P&WA who developed it into the Pratt & Whitney JT12 . The team had to wait for market assessments to define their next engine, a 450 shaft horsepower (340 kW) turboprop for twin-engined aircraft, the PT6. The early development of

806-421: The hottest parts need replacing or repairing more often than the cooler-running parts. If the hotter parts can be removed without disturbing the rest of the engine, for example without removing the complete engine from the aircraft, maintenance costs are reduced. It was achieved with the PT6 by having the hottest parts, the gas generator turbine and combustor, at the propeller end. They are removed without disturbing

837-427: The intake at the rear and the exhaust at the front, so that the turbine is directly connected to the propeller. Many variants of the PT6 have been produced, not only as turboprops but also as turboshaft engines for helicopters, land vehicles, hovercraft, and boats; as auxiliary power units; and for industrial uses. By November 2015, 51,000 had been produced, which had logged 400 million flight hours from 1963 to 2016. It

868-464: The power section at the front of the nacelle, where it can drive the propeller directly without the need for a long shaft. Intake air is usually fed to the engine via an underside mounted duct, and the two exhaust outlets are directed rearward. This arrangement aids maintenance by allowing the entire power section to be removed along with the propeller, exposing the gas-generator section. To facilitate rough-field operations, foreign objects are diverted from

899-428: The propeller at a speed of 1,900 to 2,200 rpm. The exhaust gas then escapes through two side-mounted ducts in the power turbine housing. The turbines are concentric with the combustion chamber, reducing overall length. In most aircraft installations the PT6 is mounted so that the intake end of the engine is towards the rear of the aircraft, leading to it being known by many as the "back-to-front" engine. This places

930-476: The rest of the engine with its connections to the aircraft. This arrangement was patented by designer Newland, one of the original PT6 team. A similar general arrangement with a free-turbine power take-off at the exhaust end (the 1,000 shp (750 kW) P.181 engine) had been shown by Armstrong Siddeley Motors at the Farnborough Airshow in 1957. An early design improvement, incorporated in

961-587: The updated SOCATA TBM -960 would be powered by the PT6E-66XT. The main variant, the PT6A , is available in a wide variety of models, covering the power range between 580 and 920 shaft horsepower (430 and 690 kilowatts ) in the original series, and up to 1,940 shaft horsepower (1,450 kilowatts) in the 'large' lines. The PT6B and PT6C are turboshaft variants for helicopters. In US military use, they are designated as T74 or T101 . Several other versions of

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