Gnome-Rhône 14N

The Gnome-Rhône 14N was a 14-cylinder two-row air-cooled radial engine designed and manufactured by Gnome-Rhône just before the start of World War II. A development of the Gnome-Rhône 14K, the 14N was used on several French and even one German aircraft.

Gnome-Rhône 14N
Type	Radial engine
National origin	France
Manufacturer	Gnome et Rhône
First run	1937
Major applications	Bloch MB.150 Messerschmitt Me 323 Amiot 351 Lioré et Olivier LeO 45
Developed from	Gnome-Rhône 14K Mistral Major
Developed into	Gnome-Rhône 14M, Gnome-Rhône 14R

Design and development

The 14K's reliability was poor, so Gnome-Rhône carried out major redesign, using different materials for the pistons and valves, and enlarging the cooling fins to increase surface area by 39%.

The 14N was introduced in 1937 and was quickly installed on several aircraft models. In 1939, minor improvements allowed Gnome-Rhône to increase the compression ratio from 6.1:1 to 6.8:1, which increased power.

The 14N was further developed into the Gnome-Rhône 14R featuring a 2-stage supercharger, but this type was not widely used until after World War II as production of improved engines was restricted by the armistice with Germany.

Variants

Data from:Aircraft engines of the World 1945,^[1] Aircraft engines of the World 1946^[2]

• 14N-2: Left hand (LH) rotation, 780 kW (1,050 hp)
• 14N-3: Right hand (RH) rotation version of N-2

• 14N-10: LH rotation, 680 kW (910 hp)
• 14N-11: RH rotation version of N-10

• 14N-16: LH rotation, 697 kW (935 hp)
• 14N-17: RH rotation version of N-16

• 14N-20: LH rotation, 846 kW (1,135 hp)
• 14N-21: RH rotation version of N-20

• 14N-44: LH rotation, 780 kW (1,050 hp)
• 14N-45: RH rotation version of N-44

• 14N-48: LH rotation, 880 kW (1,180 hp)
• 14N-49: RH rotation version of N-48

• 14N-50: LH rotation, 1,000 kW (1,400 hp)

• 14N-54: LH rotation, 930 kW (1,250 hp)
• 14N-55: RH rotation version of N-54

• 14N-58: LH rotation, 880 kW (1,180 hp)
• 14N-59: RH rotation version of N-58

Applications

• Amiot 351 (1 × 14N-38 + 1 × 14N-39)
• Amiot 354 (1 × 14N-48 + 1 × 14N-49)
• Bloch MB.131 (1 × 14N-10 + 1 × 14N-11)
• Bloch MB.135 (2 × 14M-4 + 2 × 14M-5)
• Bloch MB.150 (14N-7)
• Bloch MB.151 (14N-35)
• Bloch MB.152 (14N-25)
• Bloch MB.155 (14N-49)
• Bloch MB.161 (2 × 14N-38 + 2 × 14N-39)
• Bloch MB.170 (2 × 14N-6)
• Bloch MB.174 (2 × 14N-49)
• Bloch MB.175 (2 × 14N-48)
• Bloch MB.210 (1 × 14N-10 + 1 × 14N-11)
• Bloch MB.220 (1 × 14N-16 + 1 × 14N-17)
• Bloch MB.300 Pacifique (2 × 14N-16 + 1 × 14N-17)
• Dewoitine D.342 (2 × 14N-16 + 1 × 14N-17)
• Farman F.222.2 (4 × 14N-11)
• Farman F.224 (4 × 14N-1)
• Latécoère 611 (prototype) (2 × 14N-30 +2 × 14N-31 )
• Lioré et Olivier LeO 451 (14N-48 + 14N-49
  or 14N-38 + 14N-39 or 14N-46 + 14N-47)
• Sud-Est SE.161 Languedoc (2 × 14N-44 + 2 × 14N-45 )
• Messerschmitt Me 323 (various)
• Koolhoven F.K.58A (14N-16)
• PZL P.24F and G (14N-7)
• PZL P.24H (14N-21)
• PZL.43 (14N-1)
• SNCAO CAO.700 (4 × 14N-49)
• SNCASE SE.100 (1 × 14N-20 + 1 × 14N-21)

Specifications (14N-48)

Data from Aircraft engines of the World 1945^[1]

General characteristics

• Type: Fourteen-cylinder two-row air-cooled piston engine
• Bore: 146 mm (5.75 in)
• Stroke: 165 mm (6.50 in)
• Displacement: 38.67 L (2,360 cu in)
• Length: 1,480 mm (58.27 in)
• Diameter: 1,290 mm (50.79 in)
• Dry weight: 620 kg (1,370 lb)

Components

• Valvetrain: Two inlet and two exhaust overhead valves per cylinder
• Supercharger: Single-stage single-speed centrifugal type supercharger
• Fuel system: Stromberg carburetor
• Fuel type: 87 octane rating gasoline
• Oil system: Pressure fed at 480 kPa (70 psi)
• Cooling system: Air-cooled
• Reduction gear: 0.5:1 planetary reduction gearing

Performance

• Power output:
  
• Take-off: 880 kW (1,180 hp) at 2,650 rpm
• Military: 790 kW (1,060 hp) at 2,400 rpm at 3,900 m (12,800 ft)
• Cruise: 630 kW (850 hp) at 2,100 rpm at 3,900 m (12,800 ft)
• Specific power: 22.45 kW/L (0.49 hp/in³)
• Compression ratio: 6.8:1
• Power-to-weight ratio: 1.4 kW/kg (0.85 hp/lb)

See also

• Pratt & Whitney R-1830 a comparable engine sometimes fitted as an alternative to the 14N on French designs
• BMW 801
• Bristol Hercules
• Bristol Taurus
• Fiat A.74
• Mitsubishi Kinsei
• Nakajima Sakae
• Piaggio P.XIX
• Shvetsov ASh-82
• Tumansky M-88
• Wright R-2600