Gnome-Rhône Mistral Major
| Mistral Major | |
|---|---|
 | |
| Gnome-Rhône 14Ks in a hangar in North Africa, 1943 | |
| Type | Radial engine |
| Manufacturer | Gnome et Rhône |
| First run | 1929 |
|
| |
The Gnome-Rhône 14K Mistral Major was a 14-cylinder, two-row, air-cooled radial engine. It was Gnome-Rhône's major aircraft engine prior to World War II, and matured into a highly sought-after design that would see licensed production throughout Europe and Japan. Thousands of Mistral Major engines were produced, used on a wide variety of aircraft.
Design and development
In 1921 Gnome-Rhône purchased a license for the highly successful Bristol Jupiter engine and produced it until about 1930, alongside the smaller Bristol Titan. Starting in 1926, however, they used the basic design of the Titan to produce a family of new engines, the so-called "K series". These started with the 5K Titan, followed by the 7K Titan Major and 9K Mistral. By 1930, 6,000 of these engines had been delivered.
However, the aircraft industry at that time was rapidly evolving and producing much larger aircraft that demanded larger engines to power them. Gnome-Rhône responded by developing the 7K into a two-row version that became the 14K Mistral Major. The first test examples were running in 1929.
As the Jupiter had set the pattern for one-row radials in the 1920s, the Mistal Major became a canonical design for twin-row radials of the 1930s. It was widely licensed and formed the basis for many successful designs. Among the licensees were Industria Aeronautică Română, Manfred Weiss in Hungary, Alvis of the UK, Tumansky in the USSR, Walter of Czechoslovakia, Isotta-Fraschini and Piaggio in Italy. Nakajima in Japan also licensed it, but did not put it into production, developing their own designs based on features taken from the Mistral and other designs.
Variants
- Kbr
- Kbrs
- Kdr
- un-supercharged with reduction gearing
- Kds
- direct drive with supercharger
- Kdrs
- supercharged with reduction gearing
- Kes
- Kirs
- Knrs
- Krsd
- ?
- Kors
- opposite rotation to Kors
- Manfred Weiss WM K.14
- Piaggio P.XI
- IAR 14K
- Tumansky M-87
- ИАМ K.14
- Isotta-Fraschini K.14
Applications
- Amiot 143
- Aero A.102
- Bloch MB.200
- Bloch MB.210
- Breguet 274
- Breguet 460
- Breguet 462
- Breguet 470
- Breguet 521
- Breguet 670
- Dornier Do 17K
- Farman F.222
- Loire 46 C1
- Makhonine Mak-101
- PZL P.24
- PZL P.43
- Potez 501
- Potez 506
- Potez 62
- Potez 651
Aircraft powered by G-R 14K derivatives
- Aero A.102
- Breda Ba.65
- Breda Ba.88
- CANT Z.1007
- CANT Z.1011
- Caproni Ca.135
- Caproni Ca.161
- Heinkel He 70
- IAR 37
- IAR 80
- Ilyushin DB-3
- MÁVAG Héja
- Reggiane Re.2000
- Saab 17
- Savoia-Marchetti SM.79
- Savoia-Marchetti SM.84
- Sukhoi Su-2
- Weiss WM-21 Sólyom
Specifications (Gnome-Rhône 14Kd)
General characteristics
- Type: Fourteen-cylinder two-row air-cooled radial engine
- Bore: 146 mm (5.748 in)
- Stroke: 165 mm (6.496 in)
- Displacement: 38.673 l (2,360.0 cu in)
- Length: Kds - 1,317 mm (51.85 in)
- Kdr - 0.5 reduction gear - 1,528 mm (60.16 in)
- Kdr - 0.666· reduction gear - 1,530 mm (60.24 in)
- Kdrs - 0.5 reduction gear - 1,554 mm (61.18 in)
- Kdrs - 0.666· reduction gear - 1,556 mm (61.26 in)
- Diameter: 1,288 mm (50.71 in)
- Dry weight: Kdr 0.5 reduction gear - 503 kg (1,109 lb)
- Kdr 0.666· reduction gear - 508 kg (1,120 lb)
- Kdrs 0.5 reduction gear - 523 kg (1,153 lb)
- Kdrs 0.666· reduction gear - 528 kg (1,164 lb)
- Kds 502 kg (1,107 lb)
Components
- Valvetrain: Two Overhead valves per cylinder operated by pushrods
- Supercharger: (Kds / Kdrs - Single-speed centrifugal type supercharger)
- Fuel system: Stromberg carburetor
- Fuel type: 87 octane rating gasoline
- Cooling system: Air-cooled
- Reduction gear: Direct drive, 0.5:1 or 0.666·:1
Performance
- Power output: Kdr - 600 kW (800 hp) at sea level
- Kdrs - 580 kW (780 hp) at 1,500 m (4,900 ft) at 2,400 rpm
- Kdrs - 510 kW (680 hp) at 4,000 m (13,000 ft) at 2,400 rpm
- Kds - 560 kW (750 hp) at 1,500 m (4,900 ft) at 2,300 rpm
- Kds - 480 kW (650 hp) at 4,000 m (13,000 ft) at 2,300 rpm
- Specific power: Kdr 15.5 kW/l (0.34 hp/in³)
- Compression ratio: 5.5:1
- Specific fuel consumption: 328 g/(kW•h) (0.54 lb/(hp•h))
- Oil consumption: 20 g/(kW•h) (0.53 oz/(hp•h))
- Power-to-weight ratio: 1.52 kW/kg (0.92 hp/lb)
See also
- Related development
- Related lists
References
- ↑ Tsygulev (1939). Aviacionnye motory voennykh vozdushnykh sil inostrannykh gosudarstv (Авиационные моторы военных воздушных сил иностранных государств) (in Russian). Moscow: Gosudarstvennoe voennoe izdatelstvo Narkomata Oborony Soyuza SSR.
- ↑ Moteurs Gnome-Rhône series K (PDF) (in Spanish). Paris: Société Des Moteurs Gnome-Rhône. Retrieved 3 October 2014.
- Danel, Raymond and Cuny, Jean. L'aviation française de bombardement et de renseignement 1918-1940 Docavia n°12, Editions Larivière