Rolls-Royce Kestrel ( eng. Rolls-Royce Kestrel ) or type F - 12-cylinder aircraft engine company Rolls-Royce . The engine received its name in accordance with the naming system adopted by the company in honor of the kestrel , a small predator of the falcon family. Kestrel was the first engine of this company with a cast block of cylinders and in many ways set the trends that were developed in its later developments [1] . Since the Kestrel was used in the interwar period , it remained relatively little known, although it managed to serve well on many British aircraft of that era. The engine was also supplied abroad and even installed on prototypes of German combat aircraft, which later took part in the Battle of Britain . Several Kestrel engines remain flight-ready today.
| Rolls-royce kestrel | |
|---|---|
 | |
| Manufacturer | Rolls royce limited |
| Years of production | 1927 - 1940 |
| Specifications | |
| Volume | 21.24 L |
| Power | 685 h.p. (511 kW) at 2240 rpm on takeoff |
| Power density | 24.05 kW / l |
| Compression ratio | 6: 1 |
| Bore | 127 mm |
| Piston stroke | 140 mm |
| Number of cylinders | 12 |
| Valves | 2 intake and 2 exhaust per cylinder |
| Compressor | centrifugal drive supercharger |
| Fuel system | carburetor |
| Fuel type | 87 octane gasoline |
| Cooling system | liquid, under pressure. |
| Oil consumption | 7-13 g / (kW⋅h) |
| Dimensions | |
| Length | 1895 mm |
| Width | 620 mm |
| Height | 906 mm |
| Dry weight | 434 kg |
Content
- 1 Design and development
- 1.1 Origin
- 1.2 Cooling system
- 1.3 Improvements
- 2 options
- 3 Application
- 3.1 In aviation
- 3.2 In motor sports
- 4 surviving specimens
- 5 Specification (Kestrel V)
- 5.1 Key Features
- 5.2 Features
- 5.3 Performance
- 6 notes
- 7 Literature
Design and development
Origin
Kestrel owes its origin to the American Curtiss D-12 engine - one of the first truly successful engines with a cast block of cylinders . Earlier designs used separate steel cylinders that screwed onto the crankcase . The new technology involved casting the entire block from aluminum , followed by drilling the cylinders. This made it possible to simplify production at the same time and to achieve a significant increase in the specific power of engines, but it required investments in the refurbishment of plants [2] .
D-12 was one of the most powerful engines of its time and continued to set records. None of the British companies could offer anything like this, and when Fayrey purchased 50 of these engines (renaming them Fayrey Felix ), the Ministry of Aviation, having completely lost patience, ordered Rolls-Royce and Napier to begin work on their own engines with a cast block of cylinders.
In 1921, one of the leading designers of Napier Arthur Rowledge , the developer of the Lion engine, left the Rolls-Royce [3] . This temporarily put an end to Napier's attempts, while the Rolls-Royce gained a significant advantage. Applying all the known innovations that have appeared since the creation of the D-12 , Rowledge designed a new engine using supercharging at all heights, which allowed to surpass atmospheric engines as much as it was possible to raise the pressure of the mixture.
Cooling System
One of the key progressive solutions in the design of Kestrel was the cooling system under pressure. At normal atmospheric pressure, water boils at 100 ° C, but with increasing height this temperature drops, which forced to increase its volume, and at the same time the dimensions of the radiator for reliable cooling of the motor at high altitudes. The solution was to create excess pressure in the cooling system, which not only prevented a decrease in the boiling point at high altitude, but also raised it above normal. The design pressure in the Kestrel cooling system provided an increase in the boiling point up to 150 ° C [4] .
Enhancements
The first engines released in 1927 had a power of 450 hp. (340 kW), however, the release of an improved IB model with a capacity of 525 hp was soon launched. (390 kW). This version was widely used on Hawker Hart family aircraft , which formed the basis of the British air power in the early 1930s. Soon there was an even more significant increase in power: the V model developed 695 hp. (520 kW) at 3000 rpm. without significant design changes, and the XVI model, used on the Miles Master training aircraft, developed 670 hp. (500 kW).
Willy Messerschmitt in 1935 tested the prototype of his fighter Bf.109V1 , bearing the civil registration number D-IABI , with the Kestrel VI engine , since the corresponding German engines were not yet ready. The same engine was used by Junkers on the prototype of the Ju 87 dive bomber. The Reichsministerial Aviation acquired four Kestrel VI engines, selling the Heinkel He 70 reconnaissance vehicle to Rolls-Royce as a test bench [5] .
The growth of octane in aviation gasoline in the late 1930s. allowed to increase engine power without the risk of detonation , and the Kestrel XXX model, created in 1940, was already developing 720 hp. (537 kW) [6] .
Further development of Kestrel was the engines of Goshawk and Peregrine (and, therefore, Vulture ). In practice, Peregrine and Vulture were unsuccessful and were released in relatively small series.
Options
The engine was produced in 40 different versions, which can be divided into three groups: atmospheric, with medium and high boost pressure. One option, Kestrel VIII , was used with a propeller on the Short Singapore flying boat. In addition to pressurization, different engine options also differed in the degree of compression and gear ratio of the gearbox [7] .
Application
In Aviation
- Airco DH.9
- Arado ar 67
- Avro antelope
- Blackburn nautilus
- Blackburn sydney
- Dornier do j
- Fairey fleetwing
- Fairey hendon
- Fairey S.9 / 30 [8]
- Fokker CV
- Fokker cx
- Fokker D.XVII
- Gloster gnatsnapper
- Gloster TC.33 [9]
- Gloster TSR.38
- Handley Page Hamilton
- Handley Page Heyford
- Handley Page HP30
- Hawker audax
- Hawker demon
- Hawker fury
- Hawker hardy
- Hawker hart
- Hawker hind
- Hawker hornet
- Hawker nimrod
- Hawker osprey
- Heinkel He 70 G-1
- Heinkel he 112
- Henschel hs 122
- Junkers ju 86
- Junkers ju 87
- Messerschmitt Bf 109
- Miles master
- Miles kestrel
- Parnall pipit
- Praga E-45 [10]
- Renard R.31
- Saro A.10
- Short gurnard
- Short singapore
- Supermarine Scapa
- Supermarine southampton
- Vickers F.21 / 26
- Vickers type 150
- Vickers type 163
- Westland wizard
In motor sport
The Kestrel engine was mounted on a Wind Speed racing car, which owned world speed records from 1935-1936.
Surviving instances
Several motors are kept operational on reconditioned Hawker biplanes:
- The Hawker Hind is in the Shuttleworth Museum collection, flying regularly during the summer months.
- Hawker Demon , privately owned and also on display at the Shuttleworth Museum. The last flying aircraft of this type [11] .
- Hawker Nimrod I with a Kestrel V engine (registration number S1581 ), located in the collection of fighters of the Imperial War Museum in Duxford.
- Hawker Nimrod II with Kestrel VI engine (registration number K3661 ), also located in Duxford in the collection of historical aircraft.
Specification (Kestrel V)
Main characteristics
- Type: 12-cylinder V-shaped liquid cooling
- Cylinder diameter: 127 mm
- Piston stroke: 140 mm
- Engine displacement: 21,24 l.
- Length: 1895 mm
- Width: 620 mm
- Height: 905 mm
- Dry weight: 434 kg
Features of functioning
- Valves: overhead with one camshaft ; 2 inlet and 2 exhaust valves per cylinder
- Compressor : driven centrifugal blower
- Fuel system: carburetor
- Fuel Type: 87 octane gasoline
- Cooling system: liquid, under pressure (boiling at 150 ° C)
Performance
- Output power:
- 511 kW (685 hp) at 2240 rpm on takeoff
- 471 kW (631 hp) at 2,900 rpm at 4,400 m
- Specific Power : 24.05 kW / L
- Compression ratio : 6: 1
- Oil Consumption: 7-13 g / (kWh)
- Specific Power by Weight: 1.18 kW / kg
Notes
- ↑ Lumsden 2003, p. 190.
- ↑ Rubbra 1990, p.19.
- ↑ Lumsden 2003, p. 164.
- ↑ Rubbra 1990, p. 43.
- ↑ This aircraft was used to test the PV-12 engine, hereinafter referred to as Merlin
- ↑ Lumsden 2003, p. 196.
- ↑ Lumsden 2003, pp. 190-197.
- ↑ Taylor 1974 p.232
- ↑ James 1971 p.203
- ↑ Gray, 1972 , p. 96c
- ↑ The Shuttleworth Collection - Hawker Demon
Literature
- Erfurth, Helmut. Junkers Ju 87 (Black Cross Volume 5). Bonn, Germany: Bernard & Graefe Verlag, 2004. ISBN 1-85780-186-5 .
- Gray, CG Jane's All the World's Aircraft 1938 .-- London: David & Charles, 1972. - ISBN 0-7153-5734-4 .
- Lumsden, Alec. British Piston Engines and their Aircraft . Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6 .
- Rubbra, AA Rolls-Royce Piston Aero Engines - A Designer Remembers . Rolls-Royce Heritage Trust. Historical Series no 16. 1990. ISBN 1-872922-00-7
- Taylor, HO Fairey Aircraft since 1915. - London: Putnam Publishing, 1974. - ISBN 0-370-00065-X .
- James, Derek N. Gloster Aircraft since 1917. - London: Putnam Publishing, 1971. - ISBN 0-370-00084-6 .