Read The Battle of Britain Online
Authors: Bickers Richard Townshend
The initial example of the first production model, the Bf 109B, left the Augsburg-Haunstetten assembly line in February 1937, the impetus behind the Messerschmitt fighter enabling conversion to the new warplane of the premier Luftwaffe fighter Geschwader, JG 132 Richthofen, to begin almost immediately at Jüterbog-Damm. Indeed, the programme tempo was such that, in the following month, March, 16 Bf 109Bs were shipped direct from the factory to the Tablada airfield, Seville, for use by the Condor Legion committed to the Nationalist cause in the ongoing Spanish Civil War. Personnel of III Gruppe of JG 132 were hurriedly assigned to 2 Staffel of Jagdgruppe 88, which relinquished its He 51 biplanes, and operational status with the new fighter was achieved by late April 1937, less than three months from the first production Bf 109B rolling from the asembly line!
The early career of the Messerschmitt fighter seemed shrouded in mystery, but on November 11, 1937, a pre-series airframe, the Bf 109 V13, fitted with a specially-boosted Daimler-Benz DB 601 engine, raised the world airspeed record for landplanes to no less that 379.38mph (610.53km/h). While being blooded in action in Spanish skies, the fighter was the subject of extraordinarily rapid development. Series manufacture of the Bf 109B gave place successively to the improved Bf 109C and D, but these retained the comparatively low-powered Jumo engine. Design emphasis was now being placed on the perfection of a very much more powerful model, the Bf 109E employing the new inverted-vee Daimler-Benz engine.
The first series Bf 109E fighters began to leave the assembly lines at the beginning of 1939, all production of the fighter by the parent company having meanwhile been transferred to Regensburg. The Erla Maschinenwerk at Leipzig and the Gerhard Fieseler Werke at Kassel had become the principal suppliers and the Wiener-Neustädter Flugzeugwerke in Austria was preparing for large-scale manufacture of the fighter. The DB 601A engine of the Bf 109E had received final clearance for service use late in 1938 and, in addition to being built by the Daimler-Benz plants at Genshagen and Marienfelde, this was being produced by the Henschel Flugmotorenbau at Altenbauna and the Niedersachsische subsidiary of the Büssing-Werke of Braunschweig.
Installation of the DB 601A engine in the Bf 109 airframe transformed the performance of the Messerschmitt fighter from good to excellent. It
was a remarkable engine by international standards and its use of direct fuel injection was to endow the Bf 109E with a considerable advantage. Negative
g
, such as occurred in sudden transition from level to diving flight and interrupted the fuel supply to engines possessing normal float carburettors, no longer presented a problem, enabling the Messerschmitt fighter to out-dive its opponents. Furthermore, fuel injection reduced fuel consumption and afforded better results from relatively low octane petrol. The DB 601A was rated at 1,175hp for take-off and was thus more powerful than the Merlin then being installed in contemporary production versions of the Hurricane and Spitfire,
The Bf 109E retained the 40-mile (65km) range FuG 7 R/T equipment of earlier versions of the fighter, together with the Carl Zeiss C/12C reflector sight, armament of the initial model, the Bf 109E-1, comprising four 7.9mm Rheinmetall Borsig MG 17 machine guns. However, the Luftwaffenführungsstab by now generally favoured the more lethal if slower-firing 20mm MG FF cannon as a wing-mounted weapon and it had been decided to standardise on these as soon as the supply situation permitted. Thus, the cannon-armed sub-type, the Bf 109E-3, was to follow closely on the heels of the initial production Bf 109E-1, this retaining the twin fuselage-mounted synchronised MG 17 machine guns with 1,000 rounds per gun and mating them with a pair of MG FF cannon, each with 60 rounds, to provide a combined weight of fire of 290lb/min (131kg/min). At this juncture, no armour protection was provided for either pilot or fuel tank; these, as was also a bullet-proof windscreen, were features to be introduced in the light of operational experience.
In general, the handling characteristics of the DB 601A-engined Bf 109 were essentially similar to those of its Jumo 210A-engined predecessors, marked increases in loading notwithstanding. Admittedly, turning circle suffered somewhat and control was noticeably heavier at the upper end of the speed range. In other respects, the Bf 109E handled well. Take-off with flaps at 20 degrees was remarkably short and initial climb was excellent. Although the fighter stalled at quite high speeds, this phenomenon was gentle even under
g
, with no tendency to spin, and aileron vibration and buffeting afforded ample warning of the approach of the stall. At a normal take-off weight of 5,875lb (2,665kg), the Bf 109E achieved maximum speeds ranging from 290mph (466km/h) at sea level, through 322mph (518km/h) at 6,560ft (2,000m) to 348mph (560km/h) at
14,560ft (4,440m). A fuselage tank following the contours of the pilot's seat housed 88 Imp gal (400 litres) of fuel, but this was sufficient for only a 1.1-hour endurance at maximum continuous power at 19,685ft (6,000m), but at range cruise of 233mph (375km/h) at 22,965ft (7,000m) maximum range was 410 miles (660km). With weight reduced to 5,400lb (2,450kg), initial climb rate was 3,280ft/min (1,000m/min), and an altitude of 9,840ft (3,000m) could be attained in 3.6 min.
Whereas total Bf 109 production had barely exceeded 400 machines in 1938, no fewer than 1,091 examples of the E model were to leave the assembly lines between January 1 and September 1, 1939, representing an average monthly production tempo of 136.4 aircraft, and the spring and summer months saw the Jagdstaffeln feverishly engaged in conversion to the Bf 109E. When the codeword Ostmarkflug launched the assault on Poland, the Quartermaster-General's strength return to the Oberbefehlshaber listed 1,056 Bf 109s on Luftwaffe strength, of which 946 were serviceable.
Prior to Adler Tag, the lessons taught by the French campaign had hastily been incorporated in the Bf 109E. These included a cockpit canopy of revised design and embodying heavier framing, together with some protection for the pilot. This took the form of 8mm seat armour weighing 53lb (24kg) and a curved plate attached to the hinged canopy weighing a further 28.6lb (13kg). The fire rate of the MG FF cannon was being improved and the enhanced weapon was to be introduced by the Bf 109E-4 which rapidly replaced the E-3 during the summer and autumn of 1940.
By August 10, three days before Adler Tag, 934 Bf 109Es (against an establishment of 1,011) were available to Luftflotte 2 based in the Netherlands, Beigium and northern France, and Luftflotte 3 based in France, and of these 805 were serviceable. On Adler Tag, the Bf 109E-equipped element of the former Luftflotte was provided by the Stab and three Gruppen of each of Jagdgeschwadern 3, 26, 51 and 52, and the Stab and I Gruppe of JG 54, plus the Bf 109E-1/B and E-4/B fighter-bombers of 3/Erprobungsgruppe 210. Luftflotte 3 included the Stab and three Gruppen of each of Jagdgeschwadern 2, 27 and 53.
The Jagdflieger were aware that their Bf 109Es possessed sufficient endurance for a mere 20 minutes actual combat over Britain and that London represented the effective limit of their tactical radius. This embarrassing limitation had been foreseen and a jettisonable 66 Imp gal (300
litre) fuel tank had been developed, and, in fact, manufactured in some numbers. However, produced from moulded plywood, it was found to leak seriously after comparatively short exposure to the elements and its incendiary proclivity resulted in its rejection by Bf 109E units.
Influenced by the âStudie Blau', Hermann Goering and his staff seriously underrated the effectiveness of the British fighter opposition to be encountered. At the outset, the Bf 109Es were assigned the task of engaging the British fighters in open combat, a role for which the German fighters were ideally suited, but when the vulnerability of the twin-engined Bf 110 became obvious to the Luftwaffenführungsstab, it became necessary for the single-seaters also to provide close escort for the bombers. The fewer than 700 serviceable Bf 109Es available to Luftflotten 2 and 3 were to be found inadequate for the dual task.
Initially, the Bf 109E-equipped Jagdgruppen were able to take full advantage of the superior climbing and diving capabilities of their mounts, and the excellent tactics that had been evolved during the Spanish Civil War enabled them to play havoc with the outmoded tactics retained by RAF Fighter Command. During the first weeks of the Battle, the compact, but totally impracticable formations flown by the Hurricanes and Spitfires were frequently bounced by Bf 109Es with frightening results for the defending forces. The inflexible RAF fighter tactics were disastrous and, eventually, the defending fighters were forced to imitate their opponents.
There can be no doubt that the Bf 109E was highly effective and the master of both the Spitfire and the Hurricane in several performance respects, although it lacked certain qualities inherent in the British warplanes. The combination of cannon and machine guns provided the Messerschmitt fighter with a formidable armament and, although the MG FF cannon had a very much lower rate of fire than the Browning machine guns of the British fighters, their explosive shells could do infinitely more damage. Insofar as the Jagdgruppen were concerned, however, by September they had largely lost their freedom of action, being assigned to the close escort of bombers, and were severely handicapped in being no longer permitted to pursue the tactics best suited to the Bf 109E.
Unable by this time to use its speed to advantage, the fact that the Bf 109E could be out-turned by both Hurricane and Spitfire took on an importance that it had not previously possessed, the operational attrition of the Jagdgruppen steadily escalating. Infuriated by the losses sustained
by his bombers, Reichsmarschall Goering made matters worse by insisting that the Bf 109Es stay still closer to their charges. The Bf 109E-equipped Jagdgruppen were thus emasculated, continuing the struggle until October 31, when, the Luftwaffe having achieved little of strategic significance, the fighters were withdrawn from the assault.
Throughout the Battle, the RAF fighter pilots had treated their Bf 109E mounted opponents with the greatest respect. Indeed, most of the 1,172 aircraft lost by RAF Fighter Command during July-October 1940 had fallen to the guns of the Messemhmitt single-seater. In that period, 610 Bf 109Es had been lost on operations. During the course of the epic conflict, the Jagdflieger, who had considered themselves the hunters at the outset, had begun to see themselves as the hunted, not as the result of overwhelming qualities displayed by their opponents, but because of the strict limitations imposed on their tactics by their own Oberbefehlshaber. The Reichsmarschall had scored an âown goal', but for which the outcome of the Battle might have been different.
When committed to the Battle of Britain, the Messerschmitt Bf 110 enjoyed an awe-inspiring reputation, albeit one that owed more to German propagandists than to operational feats. Referred to as a Zerstörer, or âdestroyer â, a term borrowed from naval parlance, the Bf 110 was a product of the strategic fighter concept; a high-performance, twin-engined, multi-seat aircraft, the primary task of which was that of clearing a path through an enemy's defensive fighter screen for bombers following in its wake. Secondary roles included close escort of bomber formations and the free-ranging intruder mission within enemy airspace. The concept was particularly favoured by Goering, who saw his Bf 110-equipped Zerstörergruppen as the élite of the Luftwaffe.
Development of the Bf 110 had virtually paralleled that of the single-seat Bf 109, following the structural formula established by its stablemate and displaying much the same independence of spirit. Neither Dipl-Ing Willy Messerschmitt nor his Chief Engineer, Dipl-Ing Robert Lusser, had subscribed to the view that the requirement that the Bf 110 was intended to meet was practicable in the form envisaged by the Luftwaffenführungsstab. Accordingly, they had elected to ignore some parameters of the official specification and, as with the Bf 109, place the accent uncompromisingly on ultimate performance.
The result was an elegant and competent, indeed, outstanding combat aircraft. It was to be found supremely tractable, its basic design proving amenable to power plant changes and to accommodation of armament, avionics and other equipment far beyond anything envisaged at the time of its creation. But its designers never anticipated its deployment other than in conditions of local Luftwaffe superiority if not supremacy; a situation such as that in which the Bf 110 was to find itself over Southern England during the Battle was totally unforeseen.
No aircraft designer, however talented, had at that point in time come up with a formula enabling a large and heavy twin-engined long-range fighter to compete in terms of agility with a relatively lightly loaded short-range single-seater. Thus, the Bf 110 was to fall lamentably short of the expectations generated by the réclame of the Ministry of Propaganda in Berlin. This was to lead to a widespread belief that the Messerschmitt twin-engined fighter was an indifferent warplane. On the contrary, its lack of success in that summer of 1940 stemmed from an inadequate understanding of the intrinsic limitations of its concept rather than inherent weaknesses in the aircraft itself.
The first prototype, the Bf 110 V1, powered by two Daimler-Benz DB 600A engines each affording 910hp at rated altitude, was flown for the first time on May 25, 1936 at Augsburg-Haunstetten by Dr-Ing Hermann Wurster. During an early test phase a speed of 314mph (505km/h) was clocked in level flight at 10,830ft (3,300m) at a loaded weight of 11,025lb (5,000kg). For a relatively large, twin-engine aircraft it proved very agile and, in mock combat with a pre-series single-seat Me 109B flown by Ernst Udet, the newly-appointed Inspector of Fighter Pilots repeatedly failed to keep his larger opponent in his gun sight for sufficient time to render a hit likely, and experienced some difficulty in staying with the twin-engined fighter in steep turns.
In January 1937, as a result of evaluation of a second prototype, the Bf 110 V2, at the Rechlin Erprobungsstelle, instructions were given that Messerschmitt should commence preparations for a pre-production series of aircraft. The proposed series model, the Bf 110A, was to be powered by a pair of DB 600Aa carburettor-equipped engines affording 986hp for take-off. By the time that the pre-series Bf 110A airframes had attained an advanced stage in construction, however, the DB 600 engine was considered basically unsuited for fighter installation and was already being phased out of production in favour of the direct-fuel-injection DB 601.
The Reichsluftfahrtministerium confidently expected that the DB 601 would be available by the spring of 1938, when deliveries of the Bf 110 to the schweren (heavy) Jagdgruppen were expected to commence. Accordingly, instructions were issued to curtail the Bf 110A series, adapting the four airframes that had reached an advanced stage in assembly to take Junkers Jumo 210Da engines of 680hp for take-off.