Dinger's Aviation Pages
Bf109 Engines
It is ironic that the Bf109, the foremost German fighter of the Second World War, started and ended its life with British engines. When Willy Messerschmitt was designing the 109 the specification called for the use of the Jumo 210 engine of 610 horsepower, an engine that was so new that none were available. Instead, Messerschmitt was forced to use a Rolls-Royce Kestrel VI engine of 695 hp. German engines of the time lagged behind those being developed in Britain, but the Germans were catching up fast. It is important to note that the Messerschmitt was initially designed around a much less powerful engine than the 1,000 horsepower plus Merlin engine that British designers were planning to put in their new creations. This is one reason why the 109 is smaller than its contemporaries.
The Jumo 210, when it did arrive, was a twelve-cylinder, liquid-cooled engine with its cylinder blocks forming an inverted "V". The engine was developed from the A and B models (610hp) through the D (635hp), to the E (640hp) with a two-speed supercharger to increase altitude performance, and then to the G with 670 horsepower and fuel injection. These engines powered the 109 Bs and Cs, with many aircraft being updated with the later Jumo engines after being initially built with the slightly less powerful earlier models. The first Jumo 210 engines used a fixed wooden propeller, but later they used two-bladed metal variable pitch models.
The next production version was the D designed around the Daimler-Benz DB600A engine of 960 horsepower. This could be distinguished by having to have radiators mounted under the wing for the first time. The earlier Jumo engined B and C had only a chin radiator under the nose. Fitted with the new engine the 109 reached a new peak in performance. To use fully the power available a three-blade propeller was fitted, all later wartime 109s used three blades as well. 250 D series aircraft were produced and it used to be a bit of a mystery what happened to them, there being very few photographs of them in service. Research now seems to show that there were never enough DB600 engines and that most of the "D" airframes built were actually fitted with the Jumo 210 engine, making them look almost identical to the earlier B and C series.
In 1937, the DB601 engine was used in a specially modified "sprint" form to power the Bf 109 V13 that gained the world landplane record for Germany. This engine could produce 1,650 hp for a limited period. In its production form, it could deliver 1,175 hp. This is the engine that, in its DB601A form, powered the aircraft that swept all opposition from the sky in 1939/40 and carried the 109 into the Battle of Britain. It was a fuel injection engine, which meant that a measured dose of fuel was injected into each piston, doing away with a carburettor. This gave the 109 pilots an advantage in combat, in that they could do negative "g" manoeuvres without the engine failing. A Messerschmitt pilot could push over into a dive that a Spitfire or Hurricane pilot could not follow without losing vital moments of engine power.
The 601A engine, with its capacity of 33.9 litres was an outstanding powerplant, closely cowled it did not produce the aesthetic lines of the Spitfire or Hurricane when married to the smaller 109 airframe, but it did produce a powerful and purposeful-looking aircraft, which one RAF pilot said, "looked all engine." It should be noted however that the British Merlin engine produced almost as much power out of an engine capacity of only 27 litres. The British engine ran at a much higher speed (rpm) than the DB601 to produce this performance. This would mean much higher wear on the engine and a reduced lifespan but the service life of a fighter aircraft in WW2 was so short that this simply did not matter.
The introduction of the DB601N engine, in the Bf109E-4/N model, starting halfway through the Battle of Britain, gave a valuable increase in performance, particularly at altitude. It could use nitrous oxide injection to further boost output. This was at the expense of engine reliability (it halved the life of the engine).
In 1939, a single Bf109 was fitted with an American Pratt & Whitney R-1830 Twin Wasp radial engine. It was apparently meant to serve as a prototype for an export version of Bf109. In late 1940 another Bf109 was fitted with a BMW801 radial engine (as used on the FW190 fighter) for trials but no production order followed.
The F series that followed was also powered by the DB601, albeit more highly developed versions that, when fitted in the redesigned contours of the 109Fs nose, gave a much more pleasing appearance. The DB601E used in the F gave 1,200 horsepower.
While the Spitfire's airframe was big enough to be upgraded from the Merlin to the larger Griffon engine, the Bf109 was too small to accept the larger DB603 engine of 44.5 litres capacity. So, the next stage in the engine story of the Bf109 was the DB605A, which was essentially a DB601 with a slightly larger bore (only 4 mm wider) to give 35.7 litres capacity and made to run some 400 rpm faster to give 25 per cent more power while retaining the overall dimensions of the earlier DB601. Intended for the 109 G series, production was delayed, so the first of the G line, the G-0, made do with the DB601E. The DB605A employed the GM1 power boost system that injected nitrous oxide into the supercharger to increase performance at altitude.
The DB605D used methanol/water injection and an increased compression ratio to boost power to a staggering 1,800 horsepower in an emergency, allowing a top speed of over 400mph for the first time. When mated with the G-10 airframe a top speed of 428 mph was claimed, making it the fastest of any of the Bf 109G types.
However, the fastest of all the Bf 109s was the K series, fitted with the DB605 DB/DC engine and with methanol/water injection, the K-4 was reportedly able to reach 440 mph.
Graph showing the increase in Bf109 Engine power
After the war, the models of 109 produced in other countries progressed back through Jumo and Rolls-Royce engines! First, the S 199 made in Czechoslovakia had a Jumo 211 engine fitted, this engine, to the familiar twelve-cylinder inverted V pattern of German-developed engines, produced similar power to the DB605.
In Spain, the Hispano factory turned out versions of the 109 with the 1,300 Hispano HS-12Z engine. This was considered unsatisfactory and Rolls-Royce Merlin engines of 1,400 hp were fitted instead. These are easily identified by their four-blade propeller, deep chin radiator and the bulges on top of the nose for the cylinder banks in their upright "V" configuration.
