The name Cyclone was first used by Wright for their P-2 radial engine in 1925. The R-1820 was a improved version of the P-2 with higher displacement. The R-1820 was introduced in 1931.
The R-1820 remained in production through the 1950s by Lycoming and Canadian Pratt & Whitney.

models

• R-1820B: 575 hp
• R-1820-22: 950 hp (708 kW)
• R-1820-33: 775 hp (578 kW)
• R-1820-39: 930 hp (693 kW)
• R-1820-45: 930 hp (693 kW)
• R-1820-51: 1,000 hp (745 kW) w/turbocharger
• R-1820-53: 1,000 hp (745 kW) w/turbocharger
• R-1820-54: 900 hp (671 kW)
• R-1820-65: 1,200 hp (895 kW) w/turbocharger
• R-1820-66: 1,350 hp (1007 kW)
• R-1820-76A: 1,425 hp (1063 kW)
• R-1820-77: 870 hp (649 kW)
• R-1820-80: 1,495 hp (1100 kW)
• R-1820-82WA: 1,525 hp (1137 kW)
• R-1820-84: 1,425 hp (1063 kW)
• R-1820-86: 1,425 hp (1063 kW)
• R-1820-87: 1,200 hp (895 kW)
• R-1820-97: 1,200 hp (895 kW) w/turbocharger
• R-1820-103: 1,425 hp (1063 kW)

specifications

• 9 cylinder, air-cooled, radial
• displacement: 1,823 cubic inches (29.9 litres)
• bore x stoke: 6.125 x 6.875 inches

used by

• Douglas A-33 Martin B-10
• Boeing B-17 Flying Fortress
• Douglas B-18 Bolo
• Lockheed C-60 Lodestar
• Verton CH-21 Workhorse
• Grumman F3F
• Sikorsky H-34 Choctaw
• Grumman HU-16 Albatross
• Grumman J2F Duck
• North American P-64
• Douglas R4D-8 Skytrain
• Grumman S2F Tracker
• Douglas SBD Dauntless
• North American T-28 Trojan
• Columbia XJL-1
• Northrop YC-125 Raider