Napier Lion
| Napier | |
|---|---|
 Napier Lion at the Brooklands Motor Museum |
|
| Lion | |
| Production period: | 1918-1930s |
| Manufacturer: | Napier |
| Working principle: | Otto |
| Motor design: | Twelve-cylinder - W |
| Valve control: | DOHC |
| Drilling: | 139.7 mm |
| Hub: | 130.175 mm |
| Displacement: | 23,944 cm 3 |
| Mixture preparation: | Carburetor |
| Engine charging: | from 1922 turbocharger |
| Cooling system: | water |
| Power: | approx. 336-984 kW |
| Dimensions: | 385-459 kg |
| Previous model: | none |
| Successor: | Cub |
The Lion is a 12-cylinder W - aircraft engine from Napier . As a “W motor”, it has three banks with four cylinders each. It was designed in 1917 and produced from 1918 to the 1930s. Due to many advanced features, it was the most powerful engine of its time and therefore very popular as a drive for various racing planes, boats and cars.
history
Napier began building aircraft engines from other companies under license at the beginning of World War I. Napier was not satisfied with the foreign designs and decided in 1916 to design his own engine. It was to be a distinctive, high-performance, lightweight, high-reliability engine. So a 12-cylinder engine was designed, which should not be a V-engine with two cylinder banks, but a W-engine with three.
The engine was named Lion and the first prototypes ran in 1917. After the initial difficulties had been overcome, it went into production in 1918. The first version, the Lion-I, has an output of 335.6 kW (450 hp). In doing so, he took over the role of the "most powerful aircraft engine in the world" from the American Liberty L-12 , which was also an excellent design with an output of 400 hp (294 kW).
As the world's most powerful aircraft engine, the Lion became a huge commercial success. Due to its great popularity, it was practically ubiquitous during the years between the world wars. At that time, the Lion powered around 160 different types of aircraft. Napier hardly built anything else, and hardly a thought was wasted on replacing the Lion with a new design. In 1925, car production was given up in favor of engine production.
In performance-enhanced racing versions, the Napier Lion achieved outputs of up to 984 kW (1320 hp), which enabled it to break many world records: altitude, flight speed, long-haul flights, speeds at sea (160 km / h in 1933) and on land (Sir Malcolm Campbell's record-breaking cars like the more than 400 km / h Bluebird from 1932 and John Cobb's 634 km / h Mobil Railton Special 1947). The Lion was also able to help win the prestigious Schneider Cup in 1922 and 1927. In 1933 Hubert Scott-Paine built and drove his Miss Britain III , which was also powered by a Napier Lion, and set a world speed record for single-engine boats.
In the 1930s, a new generation of larger and more powerful engines appeared, such as the Bristol Hercules or the Rolls-Royce Merlin , which displaced the Lion from its place as the most powerful aircraft engine.
Napier consequently began to design new engines, including the Cub (a water-cooled X16 engine with 1000 hp), the 16-cylinder Rapier (an air-cooled H engine with 400 hp) and another air-cooled H engine - the 24-cylinder 1000 hp dagger . Later the water-cooled H24 engine Saber , Nomad and Deltic as well as PTL engines ( Naiad , Eland ) were added.
construction
The Lion is a W-engine with three cylinder banks of four cylinders each, which are at a 60 ° angle to each other. The engine block is made of an aluminum alloy. With a cylinder bore of 139.7 mm and a piston stroke of 130.2 mm, the engine has a total displacement of around 23,944 cm 3 . It has four-valve cylinder heads with two overhead camshafts that are driven by vertical shafts. It also has two spark plugs per cylinder. The fuel-air mixture is prepared by several carburetors. The engine is cooled with water. In its uncharged basic version of the engine has approximately 335.6 kW (450 hp) at 1950 min -1 . In the course of production of the Lion was with compressor charging and a 1922 turbocharger fitted, its performance increased standard on more than 400 kW, the high-density racing versions VII D delivers nearly 1 MW.
Technical data (Lion V)
- Type: water-cooled 12-cylinder W-engine with supercharging
- Stroke: 130.2 mm (5.125 inches)
- Bore: 139.7 mm (5.5 inches)
- Displacement: 23.94 liters
- Compression: 5: 1
- Mass: 439.4 kg
- Control: 4 valves per cylinder (2 for intake and 2 for exhaust); King shaft driven double overhead camshafts ( DOHC )
- Cooling: water
- Power: 350.5 kW at 2000 min -1
- Specific power: 14.64 kW / liter
- Power-to-weight ratio : 1.25: 1 (kg / kW)
Model variants
| model | year | rated capacity | Maximum output | Compression ratio | Dimensions |
|---|---|---|---|---|---|
| I. | 1918 | 335.6 kW at 1950 min -1 | 389.6 kg | ||
| V | until 1928 | 350.5 kW at 2000 min -1 | 372,85 kW at 2250 min -1 | 5: 1 | 439.4 kg |
| VA | ? | 372,85 kW at 2250 min -1 | 387.76 kW at 2475 min -1 | 5.8: 1 | 439.4 kg |
| VII | ? | 447.42 kW at? | ? | ? | ? |
| VII A | ? | 671.13 kW at 3300 min -1 | ? | 10: 1 | 385 kg |
| VII B | ? | 652.5 kW at 3300 min -1 | ? | 10: 1 | 421.3 kg |
| VII D | ? | 984.3 kW at 3600 min -1 | ? | 10: 1 | 421.3 kg |
| VIII | ? | 399 kW at 2350 min -1 | 417.6 at 2585 min -1 | 6.25: 1 | 421.3 kg |
| XI | ? | 402.68 kW at 2350 min -1 | 432.5 at 2585 min -1 | 6.25: 1 | 443.9 kg |
| VX | ? | 417.6 kW at 2350 min -1 | 451.15 at 2600 min -1 | ? | 458.9 kg |
use
- Avro bison
- Blackburn Blackburn
- Blackburn Darts
- Blackburn Ripon
- Blackburn Velos
- Fairey III
- Fairey Fawn
- Handley Page Hyderabad
- Heinkel HE 5
- Heinkel HD 17
- Mitsubishi B1M
- Napier-Bentley
- Supermarine p.4
- Supermarine page 5
- Supermarine Seagull (1921)
- Supermarine Southampton
- Vickers Vernon
- Vickers Valparaiso
- Vickers Victoria
- Vickers Virginia
- Vickers Vixen
- Westland Walrus
Web links
- Website with many detailed photos ; Retrieved June 9, 2016
- Detailed page on the Napier W 12 engine ; accessed on June 9, 2016