Pratt & Whitney Canada JT15D
The Pratt & Whitney Canada JT15D is a turbofan jet engine from the Canadian manufacturer Pratt & Whitney Canada in a twin-shaft design. Special technical features are the radial high-pressure compressor and the reversing combustion chamber .
development
The impetus for the development of this engine was a study carried out in 1965 into the future need for small jet engines. Thereupon, in June 1966, the design of a compact fan engine with a desired thrust between 8.9 and 11.12 kN began. Further development goals were the lowest possible number of parts, a compact design, low production and maintenance costs, little noise generation, high reliability and low specific consumption. The first run of the new engine took place on September 23, 1967.
commitment
It was first used in the twin-engine Cessna Citation . The first prototype engines were delivered to Cessna in August 1969. Of the JT15D-1 and -1A versions, which were manufactured in series from 1972 and used in the Citation, a total of 1417 engines were delivered.
The performance-enhanced version JT15D-4 was then used for the Cessna Citation II. Series production began in 1973. It was also installed in the Mitsubishi Diamond , the Aérospatiale SN 601 and the Agusta S211 . A total of 2195 pieces of this version were delivered.
The successor JT15D-5 received its approval in 1983 and was used in the Raytheon Hawker 400XP , the military Cessna T-47A and in the Scaled Composites ARES . Several sub-types were produced, which differed only slightly from the original sample. The JT15D-5A was also used in the Cessna Citation V, the JT15D-5B in the military version of the Beechcraft T-1A Jayhawk , and the JT15D-5C in the Rockwell Ranger 2000 and Agusta S211A.
The most modern version is the JT15D-5D, presented in 1993, which has a fan housing made of Kevlar , a fan in blisk technology and a high-pressure turbine with blades made of single crystals . It is used in the Cessna Citation Ultra. JT15D-5F are used in the Raytheon Beech TCX.
Technical version (JT15D-1)
The JT15 are twin-shaft turbofan engines. The air enters the vane-less fan , which has the same design as the Pratt & Whitney JT9D , but is much smaller. The air flow for the core engine is then fed to the combustion chamber via a radial compressor stage. The JT14D-4 version also has a single axial stage in front of the radial compressor, but a smaller fan and a likewise reduced bypass ratio. After the radial stage, the compressed air enters the reversing annular combustion chamber, where it changes direction by 180 °. The fuel is injected into the combustion chamber at a pressure of up to 44.8 bar. After the combustion chamber, the hot gas is again deflected by 180 ° in the direction of the turbine stages. The high-pressure turbine is single-stage, the low-pressure turbine is two-stage. The nozzle has a central cone that can be moved axially in order to change the outlet cross section depending on the power setting. The auxiliary devices are driven by a shaft that is connected to the high pressure turbine shaft. They are located in the front area of the engine. The pressure oil is supplied by a gear pump . The lubrication pressure is 5.52 bar during operation. An air turbine or an electric starter is used for starting, and 2 electric spark plugs ignite.
Technical data (overview)
| execution | Start thrust (kN) |
Continuous thrust (kN) |
Length (mm) | Fan diameter (mm) |
Transit diameter (mm) |
Dry weight (kg) |
Bypass ratio |
|---|---|---|---|---|---|---|---|
| JT15D-1 | 9.8 | 9.3 | 1506 | 691 | 223.5 | 3.3 | |
| JT15D-4 | 11.12 | 10.56 | 1600 | 686 | 253 | 2.6 | |
| JT15D-4C | 11.12 | 10.56 | 1600 | 686 | 261 | 2.6 | |
| JT15D-5 | 12.92 | 1600 | 287 | 2 | |||
| JT15D-5A | 12.92 | 1600 | 287 | 2 | |||
| JT15D-5B | 12.92 | 1600 | 292 | 2 | |||
| JT15D-5C | 14.21 | 1600 | 302 | 2 | |||
| JT15D-5D | 13.56 | 1531 | 520 | 292.6 | 3.3 | ||
| JT15D-5F | 12.92 | 1600 | 288 | 2 |
