Messerschmitt Bf109 - The Story
Few aircraft are as controversial as the Messerschmitt fighter, the main weapon of the German Luftwaffe's fighter arm throughout the second world war. During the war, allied propaganda portrayed the 109 as a mass-produced monster, which outnumbered allied pilots defeated with more manoeuvrable aircraft. This view continued after the war until the sixties, when a series of aviation historians reappraised the 109, and it was hailed as the greatest fighter design of all time. Today a more balanced view is emerging that recognises the brilliance of its design as a flying machine but does not overlook its shortcomings as a weapons system.
The 109 was designed by Willy Messerschmitt, owner of the Bavarian Aircraft Works. It drew heavily on his earlier design, the Bf 108 Taifun, a four seated touring monoplane. The prototype was produced in response to a Luftwaffe specification for a new fighter to replace its Arado biplanes. The engine to be used was a Jumo 210, but none were yet available, so Messerschmitt fitted a Rolls-Royce Kestrel engine instead. At the time aircraft design was in a transitional period with many new technologies available. Messerschmitt gave his new creation all of the new ideas on aircraft design. It was a monoplane with an enclosed cockpit, it had a retracting undercarriage and Handley-Page slats for low-speed handling. These innovations gave the design the edge on those put forward by other German firms competing for the order.
The Luftwaffe organised competitive trials for its new fighter and selected the 109, together with its rival the Heinkel 112, to have another 10 prototypes built for extended testing. The Heinkel design was more traditional than the Messerschmitt, having an open cockpit, although Heinkel did develop it, and later designs, to be remarkable aircraft with great potential; a Heinkel gained the world speed record for Germany on 30th March 1939, only to have it broken again the following month by Messerschmitt's Me209. The Messerschmitt 109 itself had secured the speed record for a landplane two years earlier in 1937.
After extended testing, the Messerschmitt Bf 109 was selected for production. Messerschmitt had done a fantastic job with the 109 design and it is churlish to try and criticise his masterpiece, however, with hindsight it is possible to see that a few elements of the 109 design made for problems later in its service life.
Messerschmitt had given the 109 exactly the armament the Luftwaffe had asked for, two machine guns. Indeed he had designed in the option of adding a third weapon to fire through the airscrew. When the Germans found out that the RAF was to have eight machine guns in its new Hurricane and Spitfire fighters there was a huge effort to match this in the 109. However, the 109's wing was just too thin to successfully accommodate more than one machine gun in each wing, and only then by using a cumbersome ammunition feed mechanism. Cut down cannon were eventually installed that gave the 109 a weight of fire more than that of the British fighters, but all the later 109s only carried wing armament slung underneath the wing rather than inside it.
The Bf 109 was a small machine compared with the British Spitfire. Although only 4% longer than the Messerschmitt, the Spitfire had 13% more wingspan and 39% more wing area. This was because the 109 was designed around an engine of only some 700 horsepower, whereas the Spitfire was always meant to have an engine of 1000 horsepower or more. It is a testament to Messerschmitt's design that the early 109s delivered had much the same performance as the later Spitfire, on much lower engine power. However, when more powerful German engines became available, their extra weight and the need to shoehorn them into the small 109 airframe while increasing the already high wing loading, led to problems. While Allied designs went on to be powered by engines of 2,000 horsepower or more the Messerschmitt only achieved such power in short bursts through the use of such devices as methanol injection. The increase in weight made the later 109s difficult to handle at low speeds, even with Handley Page slats.
The 109 was always criticised for having a very narrow track undercarriage, which made for tricky landing and taxiing. In fact it was not the narrow track alone that caused issues (the Spitfire had an even narrower track undercarriage but did not suffer the issues the Bf109 did), rather it was the narrow track combined with long stalky legs with the aircraft wheels raked out at a " negative camber angle" that produced an overall configuration that demanded very precise handing on take-off and landing and that was easily damaged by a heavy landing. It must be remembered that Messerschmitt was designing one of the very first retracting undercarriages on a fighter type anywhere in the world and his thin wing, so essential to the performance of the aircraft, precluded any other arrangement. One advantage of the design, which was never really used by the Germans, was the ability to remove the wings while the undercarriage still supported the fuselage. The nature of the German territorial gains meant that 109s could be flown directly to any battlefront. The Allies, on the other hand, often had to assemble aircraft after long sea journeys to destinations such as North Africa, Russia and the Far East. The men tasked with this work would have appreciated a design like that of the 109, which could be taken out of a packing crate in three large pieces and be reassembled without the need of jigs or hoists.
The cockpit of the Messerschmitt hinged to the side for entry and exit, this meant that it could not be left open for taxiing or slid back in flight for better vision. It also had heavy framing that obstructed the pilot's view. This latter shortcoming was overcome late in the war with the introduction of the "Erla hood" (often called the "Galland" hood) with less metalwork in the canopy and a slab of armoured glass to replace the armour plate that protected the pilot's head but also obscured vision (Erla Maschinenwerk of Leipzig built Bf109s under license and designed the improved canopy, Adolf Galland, Luftwaffe General of Fighters was the most ardent advocate of improved field of view for the 109).
No sooner were the first production Messerschmitts available than they were rushed to Spain to support the Fascist Nationalist forces of Franco as part of Germany's "Kondor Legion". Here they helped secure air supremacy for the Nationalists and evolved the tactics that would bring them success in later conflicts. The air war in Spain is often portrayed as very one-sided, but the Republican forces often gave the Germans a rough time with their Russian built I-16 fighters. The Ilyushin fighter was reported to be more manoeuvrable than the 109 and carried more guns and ammunition, but the German had the advantage of speed and could break off combat if he found himself in a dangerous position.
The Messerschmitts used in Spain were initially of the B series, followed by the C series. These used the Jumo 210 engine, which delivered less than 700 horsepower and had a maximum of five machine guns. The availability of the Daimler-Benz DB600 engine of 960 horsepower promised to improve performance and this led to the D series, which in turn was issued to the Kondor Legion in Spain. Production of the DB600 never really got underway and most of the D series were in fact fitted with the old Jumo 210 engine.
The reason the DB600 was not produced was the promise shown by the new DB601 engine that gave 1,150 horsepower and had the advantage of petrol injection. Together with the mounting of a cannon in each wing, this gave the Luftwaffe a truly formidable fighter (the Bf109E) and it was this aircraft that swept all opposition away in 1939, 1940 and 1941.
The big exception to this is, of course, the Battle of Britain, prompting the big question of which was the best fighter, the Messerschmitt or Spitfire? The answer is complex and one must remember that the Spitfire first flew six months after the Messerschmitt and its early development was not so accelerated. Thus in the Summer of 1940, the Messerschmitt was already into its fourth major mark and was on its third engine, whereas the Spitfire was in its Mark I form with the Merlin engine it was always designed to be powered by. The Messerschmitt was in the middle of its development life, its aerodynamic form already disfigured by bulges for ammunition drums, and with a wing loading greater than what it was designed for. The Spitfire was at just the beginning of its development, and its larger airframe could be pushed to take larger engines than the 109 ever could, while its larger wing area kept the wing loading within safe limits. The killing power of the 109's two cannon and two machine guns was equal to the eight machine guns of the Spitfire for fighter-v-fighter combat. The 109 was capable of turning with a Spitfire, but it could only do this at low speeds where its leading-edge slats gave it the advantage. At normal dogfight speeds, the Spitfire had the advantage. The Bf109's controls became "heavier" than those of the Spitfire at higher speeds, taking much more effort on the stick and rudder bar to hold a turn. The cramped cockpit of the 109 did not allow a pilot to bring his full strength to bear on the control column, further frustrating the German fighter pilots. The 109's engine had the advantage of fuel-injection, meaning the 109 could pull negative "G" manoeuvres to distance himself from a pursuing Spitfire.
Had the Summer of 1940 been fought along the lines of the First World War, with opposing air arms fighting each other over no-mans-land and the trenches, then the 109 would probably be remembered as the ultimate fighter, fully the master of the opposing Spitfires. As it was, in the summer of 1940, the Luftwaffe, and the Bf109 along with it, found itself being flung into the mincing machine of the strongest and most well-thought-out metropolitan fighter defence system in the world. Designed from the beginning for the defence of London this system took an increasing toll of the German attackers when they switched from assaulting the RAF directly to trying to destroy the British capital. It was as part of a larger system of radar, radio, command and control, and with the more numerous Hurricane, that the Spitfire was such a success in the Battle of Britain.
In 1941 the development of the Messerschmitt and Spitfire paralleled each other with the Bf109F having a similar performance to the Spitfire V, but from 1942 onward the Spitfire, and the other allied fighters drew ahead in terms of performance. The 109F is regarded by many as the best looking of the 109s. Messerschmitt had cleaned up the airframe and got rid of the anachronistic bracing for the tailplane, although there were some losses due to structural failure of the tail following the Fs introduction. This was found to be due to vibration at certain engine induced frequencies. The fault was cured by strengthening the tail. The F was criticized by many Luftwaffe pilots for its light armament, a single cannon and two machine guns.
In North Africa, the Balkans and Russia the 109E and F again secured German air superiority. The early, spectacular successes against the Russians gave way to a war of attrition. The Germans flying the 109, with its good performance at altitude, continued to amass victories. The Russians were playing a different game however, and they went for ascendancy through sheer strength of numbers, concentrating their resources and aircraft development on designs that excelled in the low and medium altitude bands where they operated in support of the Soviet Army. The high flying Messerschmitts found themselves superfluous, and at lower level they found themselves fighting a numerous and aggressive enemy.
On all sides, the Luftwaffe found itself first outnumbered and then outperformed by Allied fighters. There was no alternative but to try to squeeze more powerful engines and greater armament into the 109. The result was the G series, at first sharing the same lines as the F, the G later had large bulges over the nose to accommodate bigger machine-guns. All sorts of armament combinations sprouted under the wings. The G-6 was produced in huge numbers, with various armament fits it proved a potent anti-bomber aircraft. The G-10 was a fast-climbing interceptor, the fastest of the G series.
Attempts were made to produce a high altitude 109 version, the H series. These had extended wings, produced by inserting an extra wing section at each wing root, giving a span increase of 6ft 6 inches. The tailplane was also increased in span and had to be braced. With a boosted engine the 109H could reach 47,000 feet. Only a few were produced and used by a Luftwaffe reconnaissance unit in France, the rival Ta 152 design from Focke-Wulf was favoured by the Luftwaffe for high altitude work.
The Bf109 found use as a night fighter from 1943 onwards using the "Wilde Sau" tactics of Major Hajo Herrmann. Single engined fighters were vectored towards the bomber's target where they tried for visual interceptions aided by the light from the burning target and the target marking flares dropped by the bombers. Other Luftwaffe aircraft would add to the light by dropping flares. Searchlights would be shone onto the base of clouds to silhouette bombers flying above. Late in the war Bf109's used the "Naxos" receiver to home in on the ground mapping H2S Radar of British night bombers.
The 109T was a version destined for Germany's abortive Aircraft Carrier the "Graf Zeppelin". Modified from the E series the T featured arrester hook, catapult gear and folding wings. When the Carrier was cancelled the T aircraft were completed as fighter bombers. Later in the war, the Graf Zeppelin project was again picked up, this time Messerschmitt designed an all-new fighter aircraft for it, the Me 155. The new design showed a great deal of family resemblance to the Bf109. Again the Carrier was cancelled and the Me 155 was never completed in its original form. The design was modified for extreme high altitude performance and handed over to the firm of Blohm and Voss for further development and production. One prototype had been completed but crashed, and another was being built, when the war ended.
The last production 109 was the K series. These were the fastest of the 109's and mounted some of the heaviest armament ( the fearsome Mk103M 30mm cannon was planned for use). However by the time the K series became available the Luftwaffe was so short of fuel that its operations were very limited, and the K saw only limited action.
During the later part of the war, many unusual projects were planned using the 109. The Mistel combination was a 109 mounted on top of a Ju 88 flying bomb. The 109 pilot would point the Ju 88 at its target and then release his own aircraft to make his escape. Mistels were used against the allied fleet off Normandy following D-day (although the allies seem not to have noticed!). It was also planned to use them against the British fleet at Scapa Flow, but when the RAF sank the Tirpitz the British fleet was freed to sail to the far-east for the war against Japan, and the Germans lost their target.
The Zwilling project was an attempt to combine two fuselages with a new wing centre section to form a twin-boom fighter. This system was used with success by the Americans with their F-82 Twin Mustang. The Zwilling would have been a formidable aircraft with five 30mm cannon or a bombload of some 2,200 lb. Lastly, there were attempts to use as many of the components of the 109 as possible to simplify the production of a new jet fighter. By the time the design was complete, it was found that almost none of the 109 parts remained in the design, so it was abandoned.
During the War, all of Germany's allies received and operated examples of the 109. The Bulgarians and Hungarians used them, as did those parts of Yugoslavia that supported Hitler. Yugoslavia had actually purchased 109s from Germany before the war and used them against the German forces that invaded in 1941. The Italians also received Messerschmitts. Finland, assaulted by the Soviet Union in the Winter War of 1940, had found itself an ally of Germany and received many 109s for its Air Force, the last of which it retired in 1954. The Swiss had purchased 109s before the start of the war and interned many more that landed on its territory. During 1940 there were a series of air battles between Switzerland and Germany, during which the Swiss Bf109s performed very well, particularly in engagements with the 109's stable-mate the Bf110. The Swiss stopped using the 109 in 1949.
After the war production of the 109, under various guises, continued. The Czechoslovaks found themselves with a German factory for producing the 109 left on their soil, they also had another for the production of Junkers engines. To get their aircraft industry going they continued 109 production with the Jumo 211 engine. Called the Avia S199, the aircraft equipped units of the Czech Air Force. The newly independent state of Israel needed aircraft to defend itself against the Arabs. At this time the Soviet Union and its satellite states looked favourably on Israel, thinking it could extend its interests in the middle east it allowed numbers of the Avia S199s to be smuggled into Israel, despite an arms embargo.
Spain was where the Bf109 had first seen combat and Spain continued to take delivery of 109s during the War. After Germany's defeat, the Spanish continued to assemble 109s bought from Germany. They fitted their own Hispano Suiza engines to these aircraft, but the performance was unsatisfactory, and British Merlin engines were fitted instead. Known as the Hispano HA 1112, these aircraft were in service until as late as 1967. It was the retirement of these fighters and Spanish examples of the Heinkel 111 bomber, that gave the opportunity for the filming of the lavish dogfight scenes for the feature film "The Battle of Britain".
Apart from these Spanish built aircraft, a "proper" 109 did not fly for many years until 1991 when a restored 109G took to the air at the RAF station of Benson.