The Jacobs R-755 (company designation L-4) is a seven-cylinder, air-cooled, radial engine for aircraft manufactured in the United States by the
Jacobs Aircraft Engine Company.
Design and development
The R-755 was first run in 1933 and was still in production in the 1970s. With a
bore and
stroke
Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...
of 5.25 in × 5 in (133 mm × 127 mm) the
displacement
Displacement may refer to:
Physical sciences
Mathematics and physics
*Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...
was 757 cu in (12.4 L), power ranged from 200 hp to 350 hp (150 kW - 260 kW). The engine features steel
cylinders with aluminum-alloy
cylinder heads. An R-755E variant was developed for use in helicopters.
Variants
;R-755A1:The base-line direct drive production version.
;R-755A2:300 hp variant.
;R-755A3:Similar to A1 but with Scintilla magnetoes.
;R-755B1:De-rated version of the R-755A to drive a fixed pitch airscrew.
[
;R-755B2:De-rated version of the R-755A to drive a variable or controllable pitch airscrew.][
;R-755E:Up-rated engine with reduction gearing.][
;R-755EH:Developed to power the Jacobs Type 104 Gyrodyne.][
]
Applications
Engines on display
* A preserved Jacobs R-755 is on display at the Arkansas Air Museum.
* A Jacobs R-755 is on public display at the Aerospace Museum of California
*A preserved Jacobs R-755 is on display a
Super T Aviation Academy
in Medicine Hat, Canada.
* A restored Jacobs R-755A is on display at the House of Whitley.
Specifications (R-755-A1)
See also
References
External links
The Jacobs Engine - Nanton Lancaster Society
FAA Type Data Certificate Sheet - R-755
Jacobs Engine Powered Plymouth Truck
{{US military piston aeroengines
1930s aircraft piston engines
Aircraft air-cooled radial piston engines
Jacobs aircraft engines