British Salmson aero-engines refers to a series of small French designed, air-cooled

radial Radial is a geometric term of location which may refer to: Mathematics and Direction * Vector (geometric), a line * Radius, adjective form of * Radial distance (geometry), a directional coordinate in a polar coordinate system * Radial set * A ...

aero engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Aircraft using power components are referred to as powered flight. Most aircraft engines are either piston engines or gas turbin ...

that were produced by British Salmson Aero Engines Ltd, under license from

Société des Moteurs Salmson Salmson is a French engineering company. Initially a pump manufacturer, it turned to automobile and aeroplane manufacturing in the 20th century, returning to pump manufacturing in the 1960s, and re-expanded to a number of products and services ...

, in

Great Britain Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European ...

during the late 1920s and 1930s. Because the relatively low power was divided among several cylinders, the running of the engines was particularly smooth, and the

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

was very even.Salmson
in ''Flight'' magazine, April 4, 1930. Adding to the smooth running of these engines was the use of the Canton-Unne system of planetary gears in a cage connecting pistons to crank-pin.

Variants

;AD.3:Three cylinder license production of the Salmson 3 Ad ;AC.7: seven cylinder radial, capacity ;AC.9: nine cylinder radial, capacity ;AD.9: at 2000 rpm (normal power) or at 2200 rpm (maximum power). Bore of 70 mm. ;AD.9R:, geared version of AD.9 with increased bore of 73 mm and increased

compression ratio The compression ratio is the ratio between the maximum and minimum volume during the compression stage of the power cycle in a piston or Wankel engine. A fundamental specification for such engines, it can be measured in two different ways. Th ...

(6:1) (3239cc / 197.7cuin). ;AD.9NG:, increased bore and

stroke Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...

. (100 x 140 mm, 9896cc (603.9cuin) capacity).

Applications

;AD.9 * Angus Aquila * BA Swallow * Comper Swift * Boulton Paul P.41 Phoenix *

General Aircraft Monospar The General Aircraft Monospar was a family of touring and utility aircraft designed and built by the United Kingdom, British aviation company General Aircraft Ltd (GAL). Development In 1929, the Monospar Company Ltd was formed to pursue new t ...

* Hafner Revoplane * Hinkler Ibis * Parmentier Wee Mite ;AD.9R * Arpin A-1 ;AD.9NG * Cierva C.40

Specifications (AD.9)

References

Notes

Bibliography