Misplaced Pages

7K
Type	Radial engine
Manufacturer	Gnome et Rhône

The Gnome-Rhône 7K Titan Major was a seven-cylinder 370 hp (270 kW) air-cooled radial engine, that started life as an enlarged Gnome-Rhône 5K with two extra cylinders.

Development

The Gnome-Rhône 5K was itself a licensed version of the Bristol Titan. The 7K is very comparable to the Bristol Neptune seven-cylinder engine since they used the same technology. The 7K was followed by the larger and more powerful nine-cylinder 550 hp (405 kW) Gnome-Rhône 9K Mistral. Gnome-Rhône later responded to the need for a more powerful engine by developing the 7K into a two-row version that became the Gnome-Rhône14K Mistral Major.

Variants

IAM K7

Licence production in Yugoslavia by Industrija Aeroplanskih Motora- Rakovica (IAM).

IAR 7K

Licence production in Romania by Industria Aeronautică Română (IAR).

Applications

• Bernard 160
• Breda Ba.25
• Breguet 393T
• Breguet 414
• FBA 291
• FBA 294
• Lioré et Olivier LeO H-199
• Lioré et Olivier LeO 203
• Lioré et Olivier LeO H-242
• Morane-Saulnier MS.235
• Potez 33/3
• Rogožarski PVT
• Rogožarski R-100
• SET 7
• SPCA 80
• SPCA 90
• Wibault 280
• Wibault 362

Specifications (7Kd)

Data from

General characteristics

• Type: Seven-cylinder air-cooled radial engine.
• Bore: 146 mm (5.75 in)
• Stroke: 165 mm (6.50 in)
• Displacement: 19.3 L (1,180 cu in)
• Length: 146 mm (5.75 in)
• Diameter: 1,235 mm (48.62 in)
• Dry weight: 270 kg (600 lb)

Components

• Valvetrain: Pushrod operated overhead valves, two per cylinder
• Supercharger: (7Ksd - single speed centrifugal blower)
• Fuel system: Carburetor
• Fuel type: Gasoline
• Cooling system: Air-cooled

Performance

• Power output: 7Kd - 260 kW (350 hp) at 2,000 rpm at sea level for take-off

  7Ksd - 272 kW (365 hp) at 2,000 rpm at 1,500 m (4,900 ft)

  7Ksd - 250 kW (340 hp) at 2,000 rpm at 4,000 m (13,000 ft)

• Compression ratio: 5.5:1

See also

Related development

• Bristol Neptune
• Piaggio Stella P.VII

Comparable engines

• Armstrong Siddeley Cheetah
• Armstrong Siddeley Lynx
• Jacobs R-915

Related lists

• List of aircraft engines

References

Notes

1. Gunston 1989, p.74.
2. Moteurs Gnome-Rhône series K (PDF) (in Spanish). Paris: Société Des Moteurs Gnome-Rhône. Archived from the original (PDF) on 6 October 2014. Retrieved 3 October 2014.

Bibliography

• Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9

• 1920s aircraft piston engines
• Aircraft air-cooled radial piston engines
• Gnome-Rhône aircraft engines