The Bramo 323 ''Fafnir'' is a nine-cylinder radial

aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many ...

of the

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

era. Based heavily on

Siemens Siemens AG ( ) is a German multinational conglomerate corporation and the largest industrial manufacturing company in Europe headquartered in Munich with branch offices abroad. The principal divisions of the corporation are ''Industry'', '' ...

Bramo Siemens-Schuckert (or Siemens-Schuckertwerke) was a German electrical engineering company headquartered in Berlin, Erlangen and Nuremberg that was incorporated into the Siemens AG in 1966. Siemens Schuckert was founded in 1903 when Siemens & Ha ...

's earlier experience producing the

Bristol Jupiter The Bristol Jupiter was a British nine-cylinder single-row piston radial engine built by the Bristol Aeroplane Company. Originally designed late in World War I and known as the Cosmos Jupiter, a lengthy series of upgrades and developments turn ...

under licence, the Bramo 323 saw limited use.

Design and development

Development of the 323 was the end result of a series of modifications to the original Jupiter design, which Siemens licensed in 1929. The first modifications produced the Sh.20 and Sh.21. The design was then bored out to produce the 950 hp (708 kW) Sh.22 in 1930. Like the Jupiter, the Sh.22 featured a rather "old" looking arrangement with rather prominent valve pushrods on the front of the engine. In the mid-1930s the Reich Air Ministry (RLM) altered the way in which engines were assigned code names, and Bramo was given the 300-block of numbers. Therefore, the Sh.14 and Sh.22 became the 314 and 322, respectively. The 322 never matured and remained unreliable. The team continued work on the basic design, adding

fuel injection Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of an injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All comp ...

and a new

supercharger In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induct ...

. The resulting Bramo 323 was just under 27 L in

displacement Displacement may refer to: Physical sciences Mathematics and Physics *Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...

, and produced 900 PS at 2,500 rpm for takeoff, improving slightly to 1,000 PS at . The reduced power at sea level was inevitable for engines with single-speed, mechanically-driven superchargers when they were regulated to a constant maximum boost pressure below their critical altitude. The Fafnir powered a number of German prewar designs, including the Focke-Wulf Fw 200, Henschel Hs 126, Dornier Do 24 and Dornier Do 17, as well as the Focke Achgelis Fa 223 ''Drache'' helicopter. Its fairly poor fuel economy kept it from more widespread use, and most designs chose the similar BMW 132 instead, whose specific fuel consumption varied between 220 and 240 g/(kW•h) depending on model, whereas the early versions of the Fafnir got about 255 g/(kW•h), a poor figure for the era. The C/Ds, where the supercharger used less power, improved this to 230 g/(kW•h), but were only useful at lower altitudes. BMW bought Bramo in 1939 and continued production to supply the small number of designs that already used it, notably the Do 17. The naming at this point becomes somewhat confusing, with BMW, Bramo and Fafnir being used almost interchangeably depending on the source. 5,500 were produced before the lines were shut down in 1944. The original 323 design was produced in A and B models, differing in the direction they turned. The engines were intended to be installed in A/B pairs, thereby eliminating engine torque across a twin-engine aircraft. The similar C and D models featured a lower supercharger gearing for better performance at lower altitudes, improving takeoff power to 1,000 PS, but reducing the critical altitude. The final versions, P, R and T, featured a two-speed supercharger for better all-around performance. This allowed it to generate 1,000 PS at sea level as in the C/D models, but improved altitude performance considerably, delivering 940 PS at . The R-2 subtype added MW 50 water-methanol injection for added low-altitude performance, boosting power to 1,200 PS at 2,600 rpm.

Variants

;323A:(RH rotation) ;323B:same as A but opposite rotation.(LH rotation) ;323C:lower powered supercharge for take-off. (RH rotation) ;323D:same as C but opposite rotation. (LH rotation) ;323J:(RH rotation) ;323M:(RH rotation) ;323P:2-speed supercharger:- at ;323R :;323R-2:with 'C3' 96 octane fuel injection at 2,600 rpm ;323T:

Applications

* Arado Ar 196 * Arado Ar 232 *

Blohm & Voss BV 222 The Blohm & Voss BV 222 ''Wiking'' (Pronounced "Veeking") was a large, six-engined German flying boat of World War II. Originally designed as a commercial transport, it was the largest German seaplane to attain production status during the war. ...

* Dornier Do 17 * Dornier Do 24 *

Focke Achgelis Fa 223 The Focke-Achgelis Fa 223 ''Drache'' () was a helicopter developed by Germany during World War II. A single Bramo 323 radial engine powered two three-bladed rotors mounted on twin booms on either side of the cylindrical fuselage. Although th ...

* Focke-Wulf Fw 200 * Henschel Hs 126 * Junkers Ju 352

Specifications (BMW-Bramo 323J)

Notes

External links

German language article on the Bramo 323 with images
{{BMW aeroengines Aircraft air-cooled radial piston engines BMW aircraft engines 1930s aircraft piston engines