Jacobs R-915

Summary

The Jacobs R-915 or Jacobs L-6 is a seven-cylinder, air-cooled, radial engine for aircraft manufactured in the United States, production started in 1936.[1]

R-915
Jacobs engine, BT-13 - Evergreen Aviation & Space Museum - McMinnville, Oregon - DSC00478.jpg
Type Radial engine
Manufacturer Jacobs Aircraft Engine Company
Developed from Jacobs R-755

Design and developmentEdit

The R-915 was effectively an enlargement of the R-755 with strengthened stressed parts.[2] With a bore and stroke of 5.5 in × 5.5 in (140 mm × 140 mm), for a displacement of 915 cu in (15 L). Take-off power was around 330 hp (250 kW). The engine features steel cylinders with aluminum-alloy cylinder heads.

VariantsEdit

R-915A1
Baseline variant; an enlarged R-755
R-915A3
Similar to the A1 but with Scintilla magnetoes
R-915A4
With a power take-off for autogyros

ApplicationsEdit

Engines on displayEdit

Specifications (R-915A1)Edit

Data from Jane's[5]

General characteristics

  • Type: 7-cylinder air-cooled radial piston engine
  • Bore: 5.5 in (140 mm)
  • Stroke: 5.5 in (140 mm)
  • Displacement: 915 cu in (15 L)
  • Length: 40 in (1,030 mm)
  • Diameter: 45.5 in (1,160 mm)
  • Dry weight: 555 lb (252 kg)

Components

  • Valvetrain: 2 valves per cylinder (pushrod-actuated); sodium cooled exhaust valves
  • Fuel system: Single Stromberg NA-R7A carburetor
  • Fuel type: 80 octane
  • Oil system: One pressure pump, two scavenge pumps
  • Cooling system: Air-cooled
  • Reduction gear: Direct drive, right hand tractor

Performance

See alsoEdit

Related development

Comparable engines

Related lists

ReferencesEdit

NotesEdit

  1. ^ Gunston 1989, p.85.
  2. ^ Wilkinson, Paul H. (1950). Aircraft engines of the World 1950 (8th ed.). London: Sir Isaac Pitman & Sons Ltd. p. 161.
  3. ^ Nanton Lancaster Society: Jacobs L-6 MB Retrieved: 23 July 2015
  4. ^ The Canadian Museum of Flight - L-6 Retrieved: 31 January 2009
  5. ^ Janes 1989, p.305.

BibliographyEdit

  • Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9
  • Jane's Fighting Aircraft of World War II. London. Studio Editions Ltd, 1989. ISBN 0-517-67964-7

External linksEdit

  • Jacobs L-6 MB, Bomber Command Museum of Canada - Nanton Lancaster Society
  • FAA Type Data Certificate Sheet - R-915