Main Menu

Pratt & Whitney R-1535 Twin Wasp Junior

 

PW-R-1535

 

The Pratt & Whitney R-1535 Twin Wasp Junior was an engine used in American aircraft in the 1930s. The engine was first introduced in 1932 as a 14 cylinder version of the 9-cylinder R-985. It was a two-row, air-cooled radial design. Displacement was 1,535 in³ (25.2 lt); bore and stroke were both 5-3/16 in (131.8 mm).

 

Variants:
R-1535-11 - 750 hp (559 kW)
R-1535-13 - 750 hp (559 kW), 825 hp (615 kW)
R-1535-44 - 625 hp (466 kW)
R-1535-72 - 650 hp (485 kW)
R-1535-94 - 825 hp (615 kW)
R-1535-96 - 825 hp (615 kW)
R-1535-98 - 700 hp (521 kW)
R-1535-SB4-G - 825 hp (615 kW)

 

Applications:
Bellanca 28-70
Breguet 695
Curtiss SBC-3 Helldiver
Douglas O-46
Fokker D.XXI (Finnish licence-built series 4 and 5)
Grumman F2F
Hughes H-1 Racer
Miles Master
Northrop A-17
Northrop BT
Vought SBU Corsair
Vought SB2U Vindicator

 

Specifications:
R-1535-SB4-G
Type: Fourteen-cylinder two-row supercharged air-cooled radial engine
Bore: 5 3⁄16 in (131.8 mm)
Stroke: 5 3⁄16 in (131.8 mm)
Displacement: 1,534.9 in³ (25.153 l)
Length: 53.27 in (1,353 mm)
Diameter: 44.13 in (1,121 mm)
Dry weight: 1,087 lb (493 kg)
Valvetrain: Two overhead valves per cylinder
Supercharger: Single-speed centrifugal type supercharger, 11:1 reduction
Fuel system: Two-barrel Stromberg carburetor
Fuel type: 87 octane rating gasoline
Cooling system: Air-cooled
Reduction gear: Epicyclic gearing, 0.75:1
Power output: 825 hp (615 kW) at 2,625 rpm for takeoff
Specific power: 0.54 hp/in³ (24.45 kW/l)
Compression ratio: 6.75:1
Specific fuel consumption: 0.49 lb/(hp•h) (295 g/(kW•h))
Oil consumption: 0.39 oz/(hp•h) (15 g/(kW•h))
Power-to-weight ratio: 0.76 hp/lb (1.25 kW/kg)

 

 

 

 

 


Copyright © 2017 all-aero. All Rights Reserved.
Joomla! is Free Software released under the GNU General Public License.