The Bf 109F was widely considered to be the best basic variant of the 109 produced. Work began on the new version at the start of 1940, with pre-production models first appearing at the end of 1940. The best version, the F-4, appeared at the start of 1942. By the end of that year the 109F had been largely superseded by the 109G, a rather heavier, fast, but less manoeuvrable version of the fighter. Other changes included a change to the wing plan, where the clipped wing ends were replaced by rounded tips. The wing-mounted guns were abandoned as they weakened the wings, although provision was made to mount guns under the wings, which reduced the performance of the fighter.
Development and Changes
The main change planned for the Bf 109F was a move to the DB 601E engine. The engine cowling was redesigned, producing a more symmetrical fighter. Combined with a larger airscrew spinner and shorter propeller blades the result was to increase the potential speed and manoeuvrability of the 109 quite considerably. Even before the correct engine was available, the new airframe provided a significant improvement on the 109E.
When the 109F appeared at the start of 1941 it proved itself to be more than equal to the Spitfire V. The only complaint most pilots had about the 109F was that is was under-armed. The R-1 field conversion was one attempt to solve this problem (see F-4 below), which would remain until the MG 17s were replaced by two MG 131 13mm machine guns in the Bf 109 G-5/ G-6.
It had originally been expected that the 109F would be the final version of this fighter, before newer aircraft replaced it. However, the replacement projects all failed, and so the Messerschmitt design team moved onto the Bf 109G. The main problems faced by the F series were speed and maximum effective altitude. As heavy allied bombers appeared the Bf 109F proved to be a little too lightweight to cope, and so the most manoeuvrable model of the fighter had to be replaced.
The 109F airframe was ready before the DB 601E engine. Accordingly the 109F-0 pre-production model was given the same DB 601N engine as the 109E-4/N. It was armed with two MG 17s in the engine cowling and one MG/FF M cannon (it had been planned to use the MG/151 but that gun was not yet ready). In evaluation tests in the autumn of 1940 the 109F-0 proved itself to be superior to the 109E-4/N, out-turning and out-climbing it.
Essentially the same as the F-0, the F-1 had the DB 601 N engine, all of the aerodynamic improvements planned for the F series and was armed with two MG 17s over the cowling and one MG FF cannon in the engine. It was delivered to service evaluation units late in 1940, and to front line units from the start of 1941.
Fighter bomber fitted with the ETC 250 bomb rack, capable of taking one SC 250 bomb.
The F-1/Trop was a field modification for desert conditions. It was produced by fitting Italian filters to the standard F-1. Not many aircraft were converted to this type before proper factory-produced Bf 109F-2/Trops began to appear.
The F-2 saw the MG 151/15 cannon finally enter service. It appeared in april 1941. Otherwise the F-2 was similar to the F-1, with the same MG 17s in the fuselage and the DB 601N engine.
The fighter-bomber version, fitted with the ETC 250 bomb rake taking one SC 250 bomb
The first factory-produced desert variant of the 109F. The F-2/Trop had desert dust filters, a larger super-charger intake and was equipped with desert survival equipment.
The F-2 but with the addition of the GM-1 nitrous oxide power boost system and the VDM propeller with a wider blade. It also had a larger super-charger intake and a deeper oil cooler. These changes eventually became standard on the Bf109G.
The first version to be built around the DB 601 E engine, as originally intended. It was armed with on engine mounted cannon (probably the MG 151/20) and two cowling mounted MG 17s. Both JG 2 and JG 26, based on the Channel Front, received some examples of this version over the winter of 1941/2 but it never entered widespread service.
The first mass-produced version to use the DB 601 E-1 engine. It was armed with one MG 151/20 in the engine and two MG 17s in the engine cowling. It was the most numerous sub-type of the 109F, and remained in service until 1943. Many experts considered it to be the best of the 109Fs, and thus the best 109 all round. The 109F-4 was what Messerschmitt had intended the 109F to be all along.
Three Rustsatze (field conversion kits) were in common use with the 109F-4. The R-1 saw an MG 151/20 cannon mounted under each wing. R-5 was a 300 litre drop tank, slung under the fuselage. Finally R-6 was an ETC 250 bomb rack capable of taking one 250 kg bomb.
F-4/B, F-4/Trop and F-4/Z
These were the same as their F-2 equivalents (see above).
A tactical reconnaissance fighter. The engine mounted camera was removed and (probably) replaced by a Rb 50/30 camera and the R-3 300 litre drop tank. Some sources suggest no camera was fitted, and pictures were taken using a hand-held camera.
The main reconnaissance version of the 109F. It had the DB 601E engine, the R-3 drop tank and was equipped with either an Rb 20/30, Rb 50/30 or Rb 75/30 camera mounted behind the cockpit. It was produced in limited numbers, but remained in used until 1943. It was often seen over the Western Desert or Malta, outrunning pursuing Spitfires.
Overall just over 2,000 109Fs were built (16% of the total) before this model was replaced by the 109G.
The Bf 109F was the main Luftwaffe fighter at the start of Operation Barbarossa. The Russian front saw the German fighter “Experte” achieve the highest number of victories achieved on any front (or in any war). Over seventy German fighter pilots achieved more than 100 victories, eight claimed over 200 and two reached 300. There were several reasons for this, but one of the most important was that the Bf 109F (and the later 109G) was vastly superior to most Soviet aircraft at the start of the war, and retained that advantage until quite late. A second major advantage was that many Bf 109 pilots had years of combat experience, gained in Spain, Poland, France and over Britain.
In contrast, Stalin’s purges had removed most experienced pilots from the Russian air force. Their replacements were poorly trained and denied any initiative. Their undoubted bravery could not make up for these disadvantages (the Luftwaffe later found itself in the opposite situation in the west, where rushed training meant that many new pilots were very vulnerable against their better trained British and American opponents). The war in the air in the east closely resembled the war on the ground. Wave after wave of Soviet aircraft slowly overwhelmed the smaller numbers of technically superior German fighters. Despite the massive scores achieved by so many German pilots, this attrition slow wore them down.
Mid 1942 saw many units begin to replace their 109Fs with the newer Fw 190. This aircraft soon replaced the 109 in the central and northern fronts, although the 109 remained in use elsewhere on the front line. At the same time, the 109G was beginning to replace the 109F. This model was perhaps better suited to conditions on the eastern front, where its sturdier design made it better able to operation from poorer quality air fields.
The 109F arrived too late to take part in the crucial battles over Britain in 1940. Most 109F equipped units soon moved east to take part in the invasion of Russia. Only JG 2 “Richtofen” and JG 26 “Schlageter” remained in the west to defend against the British. However, in contrast to the events of 1940, this time it was the R.A.F. who were on the offensive, and so many of the disadvantages faced by the Bf 109 over Britain were now reversed. The R.A.F. was now operating at long range, over enemy territory. British fighters shot down on their “circus”, “rhubarbs” or “rodeos” over France were lost to the R.A.F. (Douglas Bader is perhaps the most famous example of this). The 109F was soon superseded by the Fw 190, which began to appear in August 1941. However, the 109F remained in service long enough to help Adolf Galland win his 70th victory. As a result, Galland became the first man to be awarded the Swords to the Knight’s Cross, a newly inaugurated award for bravery.
The constant fighting over France began to show up some weaknesses in the 109F. More than one “Experte” was lost when the wing collapsed. The high performance of this version came at the cost of some structural weakness.
The 109E had been the standard German fighter in Africa since May 1940, when the first Luftwaffe fighter units moved to Libya. The “Emil” faced superior numbers but of slightly inferior fighters – the best British fighter to reach the desert at this time being the Hurricane.
The 109F arrived in Africa in the autumn of 1941. The new model increased the advantage held by the Germans on a fighter to fighter basis, but the first signs of a more worrying long term now began to appear. Fuel shortages began to plague the Luftwaffe’s desert air force, reducing their effectiveness. Worse, the German planes were now always fighting against larger numbers of enemy fighters. If that allied numerical advantage could be matched by the quality of the aircraft, then the 109 would be in terrible trouble.
1942 saw the desert war turn permanently against the Germans. It had begun well. Rommel’s attacks in May had forced the British to retreat back almost into Egypt, stopping at El Alamein. The air battles associated with Rommel’s final advance saw the first Spitfires appear in Africa. The period also saw the arrival of American heavy bombers in Africa. It also saw the arrival of the 109G, although the 109F remained in active service until early 1943.
This period also began to see weaknesses in the Luftwaffe’s organisation and training systems have an impact at the front. One of the reasons that many German aces scored so many victories was that they remained on active service until they were wounded, killed (or sometimes promoted). In contrast, Allied pilots served a fixed tour of duty before returning to Britain to perform training duties. Although this was unpopular with the pilots, it did mean that new allied pilots had received training from combat veterans. In contrast, Luftwaffe replacement pilots were badly under-trained. In many Luftwaffe units the vast majority of victories were won by the experienced experts, and fell off dramatically when they were lost in action.
As the 109F was slowly replaced by the 109G, the German desert air force was thrown onto the defensive. El Alamein saw the beginning of a period of prolonged retreat that for many would not end until they had been forced back all the way into Germany, via Sicily and Italy. Many aircraft were lost when their airfields were over run, this time not to be recaptured later. Overwhelming allied strength, both in the air and on the ground, had won the battle in Africa.
DN 601 1 E
1350 hp at take off
9.93m / 32 ft 6.5 inch
8.94 / 29 ft 7 1/8 inch
There appears to be no consensus over the speed of the Bf 109F-4. Different sources provide different maximum speeds ranging from 394 mph down to 354 mph. When compared to later variants with more widely accepted performance figures, it appears likely that these represent the maximum emergency speed at the top end and the normal combat speed at the bottom. Cruising speed was lower, probably around 300 mph.
11600 m/ 38,000 ft
400 miles, boosted to 525 miles with the 300l drop tank.