Siemens & Halske Sh 12

Sh 12 to drive a VL Sääski in the Finnish Aviation Museum

The Siemens & Halske Sh 12 is a German aircraft engine from the company of the same name in Berlin-Siemensstadt .

development

The nine-cylinder Sh 12 engine was developed in 1925 together with the five and seven-cylinder versions Sh 10 and Sh 11 . In this series, Siemens & Halske used cylinders with attached heads made of light metal for the first time to improve the cooling properties . After the in-house test runs, the engines went to the DVL in Berlin-Adlershof in autumn 1926 and passed the type test there, including 150-hour runs under full load . At the suggestion of Siemens, the number of hours for the Sh 12 was doubled to 300 hours, which were completed without any complaints. After successfully completing all tests, the type certification was issued and the engine was transferred to series production, which continued until 1930. The number of units was 520 Sh 12 built, to which a number of Hungarian licensed buildings were added. The Sh 12 was also an international success and was exported to Finland, Japan, Yugoslavia, Latvia, Mexico, the Soviet Union and the USA. In the latter it was built under license as Ryan-Siemens 9 . In Germany, it was mainly used in sports aircraft and smaller commercial aircraft of the 1920s and 1930s.

construction

The Sh 12 is an air-cooled nine-cylinder - four stroke - radial engine . Low over which the provided with cooling ribs steel cylinder liner pulled down ribbed cylinder heads placed from cast light metal. The combustion chamber is hemispherical.

use

Unclad Sh 12 in use on a VL Sääski

• Albatros L 68
• Albatros L 69
• Albatros L 79
• Arado SI
• Arado S III
• Arado W II
• BFW-1
• Dietrich DP II
• Focke-Wulf A 16
• Focke-Wulf GL 18
• Focke-Wulf GL 22
• Heinkel HD 32
• IVL K.1
• Junkers K 16
• Messerschmitt M18
• Messerschmitt M21
• Raab-Katzenstein class 1
• Raab-Katzenstein RK 2
• Taylor Chummy
• Udet U 8
• Udet U 11
• Udet U 12
• VL Paarma
• VL Sääski
• White WM-10

Technical specifications

A partially disguised Sh 12 in a Hungarian U 12 Flamingo with free-standing cylinders

Parameter	Data
length	814 mm
width	1028 mm
height	1028 mm
drilling	100 mm
Hub	120 mm
Total displacement	8.5 l
compression	5.6
Starting power	125 hp (92 kW) at 1750 rpm
Nominal power on the ground	112 hp (82 kW) at 1650 rpm
Continuous performance on the ground	108 hp (79 kW) at 1500 rpm
Dry weight	176 kg
Power to weight ratio	1.38 kg / hp
Displacement	14.71 hp / l
Fuel consumption with continuous power	230 hp / h
Lubricant consumption at continuous output	12 g / PSh
Octane number	80

literature

• Kyrill von Gersdorff, Kurt Grasmann: aircraft engines and jet engines . In: German aviation . Bernard & Graefe, Munich 1981, ISBN 3-7637-5272-2 , pp. 46 .
• Helmut Stützer: The German military aircraft 1919–1934 . E. S. Mittler & Sohn, Herford 1984, ISBN 3-8132-0184-8 , p. 234 .

Web links

Commons : Siemens-Halske Sh 12  - Collection of images, videos and audio files

Individual evidence

1. ↑ Ulrich Thuer: Siemens & Halske Sh 14. Air cooling vs. Water cooling . In: Aviation Classics . No. 05/2018 . Motor Presse, Stuttgart, p. 38 .