Napier Dagger
The Napier Dagger was a 24-cylinder aircraft engine made by Napier & Son .
history
The management of Napier & Son hired the freelance designer Frank Halford in 1929 . Halford designed an H-engine with a large number of small air-cooled cylinders and extraordinarily high speeds, which was different from all previous developments at Napier. This engine, known as the Napier Rapier , had 16 cylinders, four in a row, and two crankshafts that drove the centrally located propeller shaft via a gearbox.
The rapier was the forerunner of the Dagger, which had 24 slightly larger cylinders in an H-arrangement. The displacement was 16.84 L. The first versions from 1934 delivered 635 hp. Later versions from 1936 already delivered 950 hp at 4000 rpm. The Dagger VIII installed in the Handley Page Hampden, for example, developed 1000 hp at an altitude of 2600 m and reached the "magic limit" of one hp per cubic inch of displacement at the time.
The dagger was a complicated machine. At that time, there were engines with a much simpler structure and the same high output. The Dagger also made a lot of noise and was quite unreliable.
Technical specifications
Napier Dagger
- Design: air-cooled, supercharged 24-cylinder aircraft engine in H-design
- Displacement: 16.84 l
- Bore: 97 mm
- Stroke: 95 mm
- Output: 635-1000 hp (at 4000 rpm)
application
literature
- B. Gunston: The Planes of World War II - plan drawings. Heel-Verlag, 1999, ISBN 3-89365-785-1 .
