Wright R-1820 Cyclone

The Wright R-1820 Cyclone 9 is an American radial engine developed by Curtiss-Wright, widely used on aircraft in the 1930s through 1950s. It was produced under license in France as the Hispano-Suiza 9V or Hispano-Wright 9V, and in the Soviet Union as the Shvetsov M-25.

R-1820 Cyclone
Curtiss-Wright R-1820 Cyclone Radial Engine
Type	Radial engine
National origin	United States
Manufacturer	Wright Aeronautical
First run	1930s
Major applications	Boeing B-17 Flying Fortress Curtiss P-36 Hawk Douglas B-18 Bolo Douglas DC-3 Douglas SBD Dauntless General Motors FM-2 Wildcat Sikorsky H-34 North American T-28 Trojan
Number built	47,475[1]
Variants	Shvetsov M-25
Developed into	Wright R-2600 Wright R-3350

Design and development

The R-1820 Cyclone 9 represented a further development of the Wright P-2 engine dating back to 1925. Featuring a greater displacement and a host of improvements, the R-1820 entered production in 1931. The engine remained in production well into the 1950s.

The R-1820 was built under license by Lycoming, Pratt & Whitney Canada, and also, during World War II, by the Studebaker Corporation. The Soviet Union had purchased a license for the design, and the Shvetsov OKB was formed to metricate the American specification powerplant for Soviet government-factory production as the M-25, with the R-1820's general design features used by the Shvetsov design bureau for many of their future radials for the Soviet air forces through the 1940s and onwards. In Spain the R-1820 was license-built as the Hispano-Suiza 9V or Hispano-Wright 9V.^[2]

The R-1820 was at the heart of many famous aircraft including early Douglas airliners (the prototype DC-1, the DC-2, the first civil versions of the DC-3, and the limited-production DC-5), every wartime example of the Boeing B-17 Flying Fortress and Douglas SBD Dauntless bombers, the early versions of the Polikarpov I-16 fighter (as the M-25), and the Piasecki H-21 helicopter.

The R-1820 also found limited use in armored vehicles. The G-200 variant developed 900 hp (670 kW) at 2,300 rpm and powered the strictly experimental M6 Heavy Tank.

D-200 Diesel

The Wright R-1820 was converted to a diesel during World War II by Caterpillar Inc. as the D-200 and produced 450 hp (340 kW) at 2,000 rpm in the M4A6 Sherman.^[3]

Variants

R-1820-04

700 hp (520 kW)

R-1820-1

575 hp (429 kW)

R-1820-4

770 hp (570 kW)

R-1820-19

675 hp (503 kW)

R-1820-21

690 hp (510 kW)

R-1820-22

950 hp (710 kW)

R-1820-25

675 hp (503 kW), 750 hp (560 kW), 775 hp (578 kW)

R-1820-32

1,000 hp (750 kW)

XR-1820-32

800 hp (600 kW)

R-1820-33

775 hp (578 kW)

R-1820-34

940 hp (700 kW), 950 hp (710 kW)

R-1820-34A

1,200 hp (890 kW)

R-1820-40/42

1,100 hp (820 kW), 1,200 hp (890 kW)

R-1820-41

850 hp (630 kW)

R-1820-45

800 hp (600 kW), 930 hp (690 kW)

R-1820-49

975 hp (727 kW)

R-1820-50

850 hp (630 kW)

R-1820-52

1,000 hp (750 kW)

R-1820-53

930 hp (690 kW), 1,000 hp (750 kW)

R-1820-56

1,200 hp (890 kW), 1,350 hp (1,010 kW)

R-1820-57

1,060 hp (790 kW)

R-1820-60

1,200 hp (890 kW)

R-1820-62

1,350 hp (1,010 kW)

R-1820-66

1,200 hp (895 kW), 1,350 hp (1,007 kW)

R-1820-67/69

1,200 hp (890 kW), fitted with turbosupercharger

R-1820-72W

1,350 hp (1,010 kW), 1,425 hp (1,063 kW)

R-1820-74W

1,500 hp (1,100 kW)

R-1820-76A,B,C,D

1,425 hp (1,063 kW)

R-1820-77

1,200 hp (890 kW)

R-1820-78

700 hp (522 kW), 1,100 hp (820 kW)

R-1820-80

700 hp (520 kW), 1,535 hp (1,145 kW)

R-1820-82WA

1,525 hp (1,137 kW)

R-1820-84

1,525 hp (1,137 kW)

R-1820-86

1,425 hp (1,063 kW)

R-1820-97

1,200 hp (890 kW), fitted with turbosupercharger

R-1820-103

1,425 hp (1,063 kW)

SGR-1820-F3

710 hp (530 kW), 720 hp (540 kW)

SGR-1820-F2

720 hp (540 kW)

R-1820-F53

770 hp (570 kW)

R-1820-F56

790 hp (590 kW)

GR-1820-G2

1,000 hp (750 kW)

R-1820-G3

840 hp (630 kW)

R-1820-G5

950 hp (710 kW)

R-1820-G101

1,100 hp (820 kW)

R-1820-G102

775 hp (578 kW)

GR-1820-G102A

1,100 hp (820 kW)

R-1820-G102A

1,100 hp (820 kW)

R-1820-G102A

1,100 hp (820 kW)

R-1820-G202A

1,200 hp (890 kW)

R-1820-G103

1,000 hp (750 kW)

R-1820-G105

1,000 hp (750 kW)

R-1820-G205A

1,200 hp (890 kW)

Notes: Unit numbers ending with W indicate engine variants fitted with water-methanol emergency power boost systems.

Hispano-Suiza 9V

The Hispano-Suiza 9V is a licence-built version of the R-1820.^[4]

Hispano-Suiza 9Vr

9V with reduction gear

Hispano-Suiza 9Vb

Hispano-Suiza 9Vbr

variant of the 9Vb with reduction gear^[4]

Hispano-Suiza 9Vbrs

variant of the 9Vb with reduction gear and supercharger

Hispano-Suiza 9Vbs

variant of the 9Vb with supercharger^[4]

Hispano-Suiza 9Vd

variant of the 9V^[4]

Hispano-Suiza 9V-10

429 kW (575 hp) driving fixed-pitch propeller

Hispano-Suiza 9V-11

as -10 but RH rotation

Hispano-Suiza 9V-16

480 kW (650 hp) driving variable-pitch propeller, LH rotation

Hispano-Suiza 9V-17

as -16 but RH rotation

Applications

• Bloch MB.221
• Boeing B-17 Flying Fortress
• Boeing 307 Stratoliner
• Brewster F2A Buffalo
• Curtiss AT-32-A Condor
• Curtiss SBC-4 Helldiver
• Curtiss P-36 Hawk
• Curtiss SC Seahawk
• Curtiss-Wright CW-21
• Douglas A-33
• Douglas B-18 Bolo
• Douglas DC-2
• Douglas DC-3 (DST, G-102 and G-202)
• Douglas R4D-8/C-117D
• Douglas DC-5
• Douglas DF Wright SGR-1820G-2
• Douglas SBD Dauntless
• FMA AeMB.2 Bombi
• General Motors FM-2 Wildcat
• Grumman TF-1 / C-1 Trader
• Grumman E-1 Tracer
• Grumman FF
• Grumman F3F
• Grumman XF5F Skyrocket
• Grumman XP-50
• Grumman HU-16 Albatross
• Grumman J2F Duck
• Grumman S-2 Tracker
• Lockheed Model 14 Super Electra
• Lockheed Model 18 Lodestar
• Lockheed Hudson
• Martin B-10
• North American A-27
• North American O-47
• North American P-64
• North American T-28B/C/D Trojan
• Northrop N-3PB
• Northrop YC-125 Raider
• Piasecki H-21
• Polikarpov I-16
• PZL.44 Wicher
• Ryan FR Fireball
• Sikorsky S-58/HUS/HSS/H-34
• Vultee V-1

Vehicles

• M4A6 tank
• M6 heavy tank

Engines on display

Preserved Wright R-1820 engines are on display at the following museums:

• American Airlines C.R. Smith Museum^[5]
• Fleet Air Arm Museum^{[citation needed]}
• Delta Flight Museum^{[citation needed]}
• National Air and Space Museum^{[citation needed]}
• National Museum of the U.S. Air Force^{[citation needed]}
• San Diego Air & Space Museum
• Wings of Freedom Aviation Museum^[6]

• 
  Wright R-1820 Cyclone 9 engine of restored Douglas DC-3 "Flagship Knoxville" at American Airlines C.R. Smith Museum
• 
  Wright R-1820 cutaway at the Museum of Aviation
• 
  Wright R-1820 at the Museum of Aviation
• 
  Wright R-1820-82 Cyclone Radial Engine at Wings of Freedom Aviation Museum, Horsham, Pennsylvania
• 
  Curtiss Wright R-1820 Cyclone engine on display at the San Diego Air & Space Museum

Specifications (GR-1820-G2)

Data from Jane's. ^[7]

General characteristics

• Type: Nine-cylinder single-row supercharged air-cooled radial engine
• Bore: 6.125 in (155.6 mm)
• Stroke: 6.875 in (174.6 mm)
• Displacement: 1,823 cu in (29.87 L)
• Length: 47.76 in (1,213 mm)
• Diameter: 54.25 in (1,378 mm)
• Dry weight: 1,184 lb (537 kg)

Components

• Valvetrain: Two overhead valves per cylinder with sodium-filled exhaust valve
• Supercharger: Single-speed General Electric centrifugal type supercharger, blower ratio 7.134:1
• Fuel system: Stromberg PD12K10 downdraft carburetor with automatic mixture control
• Fuel type: 87 octane rating gasoline
• Oil system: Dry sump with one pressure and one scavenging pump
• Cooling system: Air-cooled

Performance

• Power output: 1,000 hp (746 kW) at 2,200 rpm for takeoff
• Specific power: 0.46 hp/in³ (20.88 kW/L)
• Compression ratio: 6.45:1
• Specific fuel consumption: 0.6 lb/(hp•h) (362 g/(kW•h))
• Oil consumption: 0.35-0.39 oz/(hp•h) (13-15 g/(kW•h))
• Power-to-weight ratio: 0.84 hp/lb (1.39 kW/kg)

See also

Related development

• Wright Cyclone family
• Wright R-1300 Cyclone 7
• Wright R-2600 Cyclone 14 (Twin Cyclone)
• Wright R-3350 Cyclone 18 (Duplex Cyclone)
• Shvetsov M-25
• Shvetsov ASh-62

Comparable engines

• Alfa Romeo 128
• BMW 114
• Nakajima Hikari
• Pratt & Whitney R-1830 Twin Wasp
• Bristol Pegasus

Related lists

• List of aircraft engines