Messerschmitt Me 109T
Luftwaffe for the Kriegsmarine - Naval Fighter, 17 built (1941-42)
The Messerschmitt Me 109 was one of the two attempts of the Luftwaffe to design a naval fighter, the after the Arado Ar 197. They were part of the Kriegsmarine Plan Z approved by Hitler in 1936, which planned the construction of four fleet aircraft carriers. Of these, only one was nearly-completed,
KMS Graf Zeppelin. Construction dragged on because of a walz of priority and Goering's Luftwaffe not in best terms with the Kriegsmarine. The naval fighter programme was eventually relaunched in 1941 on the basis of a heavily modified Mersserchmitt Bf.109 with navalized features. Only 17 were built and evaluated in the end, never used for their intended purpose.
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⚠ Note: This post is in writing. Completion expected in 2024.
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The never was aircraft carrier
Flugzeugträger “A” keel just laid in Kiel AG, 28.12.1936
Graf Zeppelin, designed in 1935 as "A" and awarded by contract on 16 November 1935 to Deutsche Werke shipyard in Kiel. However the latter was still busy constructing
KMS Gneisenau and thus, she had to wait, with the blueprints being further refined. Meanwhile, the specifications for a full naval aviation park were setup. It planned a trio comprising at first the fight Arado 197, Fi 167 torpedo bomber and Junkers 87C dive bomber. While construction dragged on, despite a launch on 8 December 1938, when the war broke out the next September 1939, construction was again suspended.
This led to a redesign of her air park, mostly swapping the Messerschmitt 109T for the Arado 197, a modern monoplane for a biplane.
Predecessor: Arado 197
Developed from the successful early Arado 68, well tested with the legion condor over Spain, the Ar 197 had its origin in the requirement for a fighter opeating on KMS Graf Zeppelin and Peter Strasser in 1936. The Ar 68H was the most modern sub-version with a fully enclosed cockpit, selected as a base for "navalization" for a new model denominated Arado Ar 197, designed by Walter Blume.
The first prototype V1 had a Daimler-Benz DB 600A inline engine coupled with with a three-blade propeller, but had no navalized features: Still straight, non folding wings no hook, not reinforcement of its fixed undercarriage. It first flew in the Spring of 1937.
The second prototype V2 had a more powerful radial BMW 132Dc and was properly navalized, testing an arrester hook, catapult spools, but still non-folding wings. By the summer of 1937 V3 had a more powerful BMW radial 132Dc 9-cyl. air-cooled rated for 656 kW (880 hp) at take-off. It was also the first armed, with two 7.92 mm (.312 in) forward wing machine guns and an engine shaft axle 20 mm Rheinmetall cannon, but also belly racks to carry four 50 kg (110 lb) bombs and an auxiliary fuel tank plus a smoke-laying canister for naval concealement.
The Ar 197 V3 was selected for a full evaluation in 1938 but not chosen for production as indeed construction of the Zeppeling dragging on, when the time the carrier would enter service, the Arado 197 would have hopelessly outclassed by new monoplanes. In 1939 it was decided to swap it for the new Bf 109T, navalized version of the now standard (and secret) Bf 109, itself later replaced by the Me 155.
Development of the Messerschmitt 109
The Messerschmitt me 109 was cutting-edge in 1939, not devoid of defaults, but efficient, easy to built. It became eventually the #1 fighter of the Luftwaffe. This fampus model, built in around 20,000 units until 1945 fought on all fronts, declined into hundreds of variants, and despite the arrival of new fighters, never replaced.
Early History
1933 Technisches Amt report
During 1933, the Technisches Amt (C-Amt), the technical department of the Reichsluftfahrtministerium (RLM) ("Reich Aviation Ministry"), concluded a series of research projects into the future of air combat. The result of the studies was four broad outlines for future aircraft:
- Rüstungsflugzeug I for a multi-seat medium bomber
- Rüstungsflugzeug II for a tactical bomber
- Rüstungsflugzeug III for a single-seat fighter
- Rüstungsflugzeug IV for a two-seat heavy fighter
The Rüstungsflugzeug III was to be short range, replacing Arado 64 and Heinkel He 51 biplanes. Late March 1933, the RLM published tactical requirements for a single-seat fighter (L.A. 1432/33)
1934 RLM specifications
Specifications included a top speed of 400 km/h (250 mph) at 6,000 m (19,690 ft), (at least for 20 minutes), and total flight duration of 90 minutes. Operational ceiling was to be 6,000 metres, reachable in 17 minutes. Maximal ceiling was to be over 10,000 metres. The new Junkers Jumo 210 engine was designated to be its engine. It developed 522 kW (700 hp).
Planned armament combinations :
-1x 20 mm MG C/30 engine-mounted cannon firing through the propeller hub as a Motorkanone
-2x engine cowl-mounted 7.92 mm (.312 in) MG 17s
-1x lightweight engine-mounted 20 mm MG FF cannon + 2x 7.92 mm MG 17s.
The MG C/30 was an airborne adaption of the 2 cm FlaK 30 anti-aircraft gun, firing the very powerful "Long Solothurn" ammunition. But the gun was heavy and cumbersome and had a low rate of fire. For wings armaments, choices were limited as wing loading should be kept below 100 kg/m2. Tests would be level speed, rate of climb, and maneuverability.
Me 109V-1
1934-35 V Prototypes
Design work on P.1034 began in March 1934 (3 weeks after the signed development contract). The basic mock-up was completed by May. A second, more detailed was shown by January 1935. The RLM designated it the "Bf 109," after the next available block of numbers (by BFW).
V1 prototype (1935)
The Versuchsflugzeug 1 completed by May 1935 had civilian registration D-IABI. But the new German engines were not yet ready therefore ironically the RLM acquired four Rolls-Royce Kestrel VI engines by trading Rolls-Royce a Heinkel He 70 Blitz for used as an engine test-bed. Messerschmitt received two of these, quickly adapted to the V1. Maiden flight occurred at the end of May 1935 south of Haunstetten, piloted by Hans-Dietrich "Bubi" Knoetzsch. After four months of testings, the aircraft was delivered in September 1935 to the Luftwaffe's central test centre at the Erprobungsstelle Rechlin, soon to be part of the design competition.
V2, V3 prototypes (1936)
The V2 was completed in October with the planned 449 kW (600 hp) Jumo 210A engine. The V3 followed, this time armed with guns, had to wait until May 1936 to receive another Jumo 210 engine.
Competition (1936)
After Luftwaffe acceptance's trials has been completed at E-Stelle, the RLM's military aviation test and development facility at Rechlin, prototypes were sent to E-Stelle Baltic, on the seacoast facility at Travemünde for the manufacturers competition. The other contenders were the
Arado Ar 80 V3,
Focke-Wulf Fw 159 V3,
Heinkel He 112 V4 and
Bf 109 V2. The He 112 arrived as early as February 1936 followed by the others the end of the month.
Me 109V-13
First impressions, first critics
Because most fighter pilots were used to biplanes with open cockpits and low wing loading, light g-forces and easy handling, they were at first very critical of the Bf 109. But it emerged as one of the frontrunners in the contest. Indeed the Arado and Focke-Wulf, which intended as "backup" programs and were completely outclassed. The Arado Ar 80 indeed had gull wings (later straight on the V3), a fixed spatted undercarriage and the design was soon abandoned.
Me 109V-1 - 3 Views Tech drawing
The Fw 159 was a parasol, potentially inspired by the earlier Focke-Wulf Fw 56, and considered by the E-Stelle like a technical compromise. It used a brand new retractable main undercarriage which was unreliable.
Bf 109 tests showed other shortcomings for the pilots like a steep ground angle (poor forward visibility when taxiing) a cockpit canopy that could not be opened in flight, trigger-happy automatic leading edge slats on the wings (later the design proved to be right). Also leading edge slats and ailerons would flutter rapidly in hard turns, possibly leading into a stall condition, and the high wing loading because of their relatively small size.
Me 109V-6 B1
The initial winner: He 112
The Heinkel He 112, was a scaled-down Blitz, a record plane and favorite by Luftwaffe leaders, included Goering. It was also cheaper than the Me 109, looked more gracious and less cramped. Moreover it had wide track and robust undercarriage opened outwards from mid wing. The Me109 at the contrary was famously plagued by inwards opening undercarriage that rendered landings and taxiing somewhat more hazardous.
The He 112 had better visibility from the cockpit, and lower wing loading, therefore landing more safely and slowly than its rival. The V4 had a single-piece, clear-view sliding cockpit canopy that was not cluttered and could be opened in flight, and its Jumo 210Da with a modified exhaust system was more powerful. In the end, Heinkel always has been the favorite in the industry, while Messerschmitt was somewhat of an underdog, producing its first fighter and somewhat ugly duck of the competition...
But the situation changed as the He 112 was structurally complicated, was 18% heavier than the Bf 109 and its thick wing, was a disadvantage for a fast fighter, as it makes it more stable and therefore decreased the aircraft's rate of roll and maneuverability. The He 112 V4 was therefore given new shorter wings. But improvements had not been fully tested and the V4 could not be demonstrated in time to the Acceptance Commission.
The Messerschmitt V4 wins
As a smaller, lighter fighter, the Bf 109 was 30 km/h (20 mph) faster in level flight, superior in climbing and diving. The Commission therefore ultimately ruled in favour of the Bf 109, notably after a convincing display from Messerschmitt test pilot's in a series of spins, dives, flick rolls and tight turns.
In March, the RLM wasinformed that the British Supermarine Spitfire had been ordered into production. Therefore a quick decision was needed to get the winning design into production asap. On March, 12 March, the RLM announced the results in the Bf 109 Priority Procurement, with a firm production order.
Me 109V-7 (wikipedia)
The Heinkel 112 is exported
At the same time, Heinkel was ordered to radically re-design the He 112, leaving hope for the company it can stay as a backup fighter. The Me 109 V1 made its public debut during the 1936 Berlin Olympics. But paradoxically, doubts were left as it was a new fighter or an acrobatic plane. In fact 54 B-0 and B-1 were to be built only, 17 included in the Legion Condor and later left to the Nationalist, 12 were given to the Japanese, 24 to Romania, wile a single one stayed in the Luftwaffe. The He 112 led to a completely revised He 100.
The Heinkel 100 as part of a deception plan
Not loosing any hope, Heinkel came back with a completely revised design, somewhat influenced by the Me 109 as it was much smaller, had reduced straight wings, a more powerful engine, the DB-601 inverted V12 (1175 hp), and a simplifed airframe. It was way faster also, reaching 670 kph on flight trials. The prototype flew on January, 22, 1938, already taking the world record at 638 kph with Udet. In March 1939, the V3 would reached a whooping 746 kph with Hans Dieterle. But the RLM don't see the necessity of a second fighter and the development is topped. Six prototypes V1 to V8 would be sent to USSR, three to Japan while the 12 He-100D-1 were included in the Heinkel own's defense unit at Rostock. They were abundantly filmed, and photographed to participate in a deception plan, making the allies believe it was the main Luftawffe's fighter by German Propaganda.
Other Me 190 Variants
Genesis of Prewar Messerschmitt Me 109s
Setting Records
Although production was approved by the RML, the new fighter made an name for itself. In July 1937 already, three Bf 109Bs took part in the Flugmeeting airshow in Zürich (under the command of Major Seidemann), winning the First prize in a 202 km speed race and class A category in the international Alpenrundflug for military aircraft, and the international Patrouillenflug category. On 11 November 1937, the V13 flown by Messerschmitt's chief pilot Dr. Hermann Wurster set a new world air speed record. Thanks to a 1,230 kW (1,650 hp) DB 601R racing engine, it reached 610.95 km/h (379.62 mph). The V13 was a Bf 109D conversion.
Heinkel, eventually gave up the He 112 and turned to the He 100, and on 6 June 1938 the V3 (Ernst Udet) broke the record at 634.7 km/h (394.4 mph). Hans Dieterle reached 746.61 km/h (463.92 mph) with the V8 on 30 March 1939, but Willy Messerschmitt regained the lead on 26 April 1939 with Flugkapitän Fritz Wendel. This time flying the 209 V1 (planned replacement for the Me 109 and called 109R for propaganda purposes) at 755.14 km/h (469.22 mph). It was powered by the DB 601ARJ (1,156 kW or 1,550 hp with a supercharger to reach 1,715 kW (2,300 hp). This world record for piston-engines stood until 1969 (Grumman F8F Bearcat Conquest I at 777 km/h (483 mph))
The Me 109A
Despite these racing trophies, Willy Messerschmitt and Robert Lusser designed initial production models of the A, B, C and D series with relatively low-powered, 670–700 PS (660-690 HP) Junkers Jumo 210 series engines. Later some prototypes were converted to use the more powerful DB 600.
The Bf 109A was the very first version of the Bf 109. It was considered as a pre-serie. Armament initially planned of only two cowl-mounted 7.92 mm (.312 in) MG 17 machine guns but with intelligence about the Hurricane and Spitfire, experiments were carried out with a third machine gun firing through the propeller shaft. The prototype V4 and some A-0 were also given the 640 PS (631 hp, 471 kW) Junkers Jumo 210B engine. The propelled was a two-blade fixed-pitch one, later changed to a 670 PS (661 hp, 493 kW) Jumo 210D when available.
The A-0 serie got production changes on the flow and diverged in their appearance. Outside the engine, cockpit and machine gun ventilation holes/slats were revised, and location of the oil cooler. These Bf 109 A-0 served with the Legion Condor, assimilated by B-series aircrafts (tactical markings 6-1 to 6–16). The 6–15 ran out of fuel and was forced to land behind enemy line, captured by Republicans on 11 November 1937 and transferred to the Soviet Union. It incorporated several improvements from the Bf 109B production program included a planned variable-pitch propeller. According to RLM archives only 22 aircraft were delivered A-series prototypes.
The Me 109B
The Bf 109 B-1 was the first large-scale production fighter, fitted with the 670 PS (661 hp, 493 kW) Jumo 210D engine, and still two-bladed fixed-pitch propeller. A more modern variable-pitch propeller was later introduced and retrofitted, these modied planes being unofficially known as B-2s. The Bf 109B saw combat with the Legion Condor during the Spanish Civil War. They only had two machines guns, but tests with an engine-mounted machine gun failed because of engine vibrations and overheating. Therefore fitting of two more machine guns in the wings followed showing they needed strengthening. The V9 prototype tested wing 20 mm MG FF cannons. 341 Bf 109 B-1s were built by Messerschmitt, Fieseler, and the Erla Maschinenwerke total.
The Me 109C
The Bf 109C arrive in the production lines in the spring of 1938. It was powered by a 700 PS (690 hp, 515 kW) Jumo 210G engine, with direct fuel injection. The wings were strengthened to carrying two machine guns, for a total of four 7.92 mm (.312 in) MG 17s. C-0s were pre-production models, C-1s were production models, and the C-2 was a prototype to test yet another engine-mounted machine gun. The C-3 had 20 mm MG FF wings cannons but either production or conversions to this model remains unknown. The planned C-4 had tested an engine-mounted Motorkanone MG FF and remained as a prototype. 58 Bf 109Cs according to the RLM (versions) has been delivered to the Luftwaffe.
The Me 109D "Dora"
The "Dora" was the second production batch of the early series, twice as much being delivered than Mark Bs. The V10 prototype, differed little from the V8, except for its Jumo 210G engine. The following V10, V11, V12 and V13 prototypes used Bf 109B airframes but with the DB 600A engine, with performances in mind. The DB 600A was quickly replaced by the DB601A with direct fuel injection. Developed from the V10 and V13 prototypes, the Bf 109D became the standard Bf 109 in service with the Luftwaffe, just before the start of World War II.
The type saw limited service as all of the 235 Bf 109Ds available at the beginning of the Poland Campaign were replaced by the Bf 109E, for a few night fighter units that kept these into early 1940. Variants of the D-series included the D-0 and D-1 models, both fitted with a Junkers Jumo 210D engine, armed with two wing-mounted and two nose-mounted 7.92 mm MG 17s. The D-2 experimented an engine-mounted machine gun agains, but without much success. In addition the next D-3 received 20 mm MG FFs in the wings.
A total of 647 Bf 109Ds of all versions were built by Focke-Wulf, Erla, Fieseler, Arado and AGO. While only four Bf 109Ds, possibly D-0 preproduction series has been originally manufactured by Messerschmitt, the others being licenced. Some Bf 109Ds were sold to Hungary, and 10 to Switzerland (built by Arado-Flugzeugwerke GmbH, Warnemünde).
Messerschmitt Me 109E ("Emil")
Studies began of the E early on in 1937. Meanwhile a total of 647 Bf 109Ds (Dora) of all sub-versions were turned by Focke-Wulf, Erla, Fieseler, Arado and AGO. Almost none were manufactured by Messerschmitt, but licenced instead, leaving the master company free to concentrate on the Emil. At that time the only engine available was the 441–515 kW (600–700 PS) Jumo 210. It was reliable, but still lacked power to allow more payloads on the Me 109 cell.
In fact, the Daimler-Benz DB 601A engine was procured. This heavier and longer power unit (181 kg (400 lb) more) packed indeed an impressive extra 223 kW (300 PS). This forced to design a quite larger cooling area, and forced the adoption of a brand new airframe, riddled with massive air intakes. In all, about 3546 Messerschmitt me 109 E or "Emil" were built, and about 12 variants and sub-variants were made, with many retrofits of surviving planes in summer of 1940.
Design specifics
Decision to modify the wings rather than simply enlarging the engine nose mounted radiator was dictated by considerations of drag and top speed only. These new radiators were placed in between the wing root and wing panels. This need to modify the trailing edges inner ends and confine the oil cooler under the nose inside a smaller streamlined duct. The counterbalancing effect of these radiator had another advantage, which was to allow the fitting of a larger three-bladed propeller made by Vereinigte Deutsche Metallwerke (VDM).
The wings has been reinforced, integrating several inboard ribs and large radiator ducting. Another inducted effect was that the radiators ends met the trailing edge of the wing's camber. Therefore the airflow was faster and the overall cooling more efficient, although with the trade-off of additional, fragile extra ducting and piping. Also, when landing, the deployed undercarriage could deflect mud and debris right into the radiators.
Me 110 E-4 "Trop"
Me109 Emil Variants
10 Me109 V14 and V15
The serie was tried by the protoypes V14 and V15. Both flew proficiently with the 1,100 PS (1,085 hp, 809 kW) DB 601A engine to test all the new plane's flight perimeter. Both prototypes were armed with 1,100 PS (1,085 hp, 809 kW) DB 601A engine two 7.92 mm (.312 in) MG 17s above the engine but V14 in addition had two 20 mm MG FF in the wings. The latter proved the new airframe cell could well carry this weight, and it was adopted later for production by the RLM, that ordered first ten E-0 to be delivered in 1938 for further evaluations, with 4 × 7.92 mm/.312 in MG 17.
1,183 Me109 E-1
Transitional production models, armed with two 7.92 mm (.312 in) MG 17s above the engine and two more in the wings. Many would be later modified to the E3 standard. In all, 1,183 E-1 would be delivered by Messerschmitt, and 110 E-1/B. The latter were the first fighter-bombers, later identified by the prefix "Bf" for Jagdbomber , or simply "Jabo". The belly and underwings were modified to carry either a central ETC 500 bomb rack (single 250 kg (550 lb) bomb) or four 50 kg (110 lb) bombs under the wings. In addition they received an improved Reflexvisier "Revi" gunsight and FuG 7 Funkgerät 7 short-range radio set.
ca 30 Me109 E-2
A few E-2 were cranked up, closely based on the V20 prototype. The Me109 E had one Motorkanone MG FF cannon in the nose and two in the wings. However the latter gave considerable trouble in service. The two synchronized MG 17s cowl machine guns also proved unreliable. The only E-2 produced were in service in August 1940 with the II./JG 27 squadron.
1276 Me109 E-3
The E-3 could be summed up as an upgrade in performance with two prototypes V16 and V17 constructed to tests structural improvements and a more powerful armament. They served as a basis for the Bf 109 E-3, armed with the hood-mounted MG 17s above the engine, and a single MG FF cannon in each wing. Total production: 1,276 E-3 including 83 E-3a export versions, which made it the most common of all Emil types.
561 Me109 E-4
The E-4 marked a new era, with many more E-3 airframes upgraded to this new standards at the start of the Battle of Britain in the summer of 1940. The Me 109 E-4 only differed in some details like the modified 20 mm MG-FF/M wing cannon, and improved neck armour above the pilot's seat. The MG FF/M could fire an improved explosive shell called Minengeschoß using drawn steel (like brass cartridges) rather than cast as usual. This resulted in a thin, light but strong cartridge able to store more explosive charge, enhancing muzzle velocity quite a bit.
This shell imposed a revision of the MG FF's mechanism due to the recoil, hence the FF/M. The cockpit canopy was simplified for production, squared-off, also improving the pilot's vision. It was later retrofitted to E-1s and E-3s, and remained in production until the introduction of the welded heavy model of the new G type in mid to late 1942. Some E-4 would received an improved DB601N high-altitude engine rated at 1,175 PS (1,159 hp, 864 kW). This E-4/N was given to just one fighter gruppe from July 1940. Me109 E-4s were also abundantly used as fighter-bombers, under the designation of E-4/B. They were fitted with the DB 601Aa engine and E-4/BN engine. Total production: 561 (496 E-4s, 250 E-4, 211 E-4/B, 15 E-4/N, 20 E-4/BN).
48 Me109 E-5/6
Both E-5 and E-6 were reconnaissance planes. A camera was installed behind the cockpit, and they were based respectively on the E-3 and E-4/N, with 29 E-5s and 9 E-6s ordered and delivered by Messerschmitt.
438 Me109 E-7
The Messerschmitt Bf 109 E-7 entered service and saw combat at the end of August 1940, and was marked by a net improvement in range: It was previously 660 km (410 mi) together with limited cruises performances. With the E-7 carrying a drop tank, standardized Luftwaffe 300 L (80 US gal) model mounted on a centre-line rack under the fuselage, it was now up to 1,325 km (820 mi). The same rack could also mount a bomb for Jabo fighter-bomber squadron operations. Retrofits of previous types were made with this belly fittings from October 1940. Standard engine was the 1,100 PS DB 601A or in alternative the 1,175 PS DB 601Aa engine. Late-production engines were 1,175 PS DB 601N with better in high altitude. This second serie was designated as E-7/N.
Battle honors
The Me 109 Emil was introduced before the war started and made the bulk of the Luftwaffe at the eve of the summer of 1940. So this was the most common version of the Me 109 throughout the western campaign, duelling with Dutch, Belgian, French planes and the RAF, from May to September 1940 at the end of the air war over Britain (The battle of Britain), where its only true rival was the Spitfire, which unfortunately was armed with a rather light -if numerous- array of standard 3 inch machine-guns. Performances of both planes has been extensively detailed during the battle and abundantly debated ever since.
The "Spit" was slightly slower in some areas, but also more agile, while the "brutish little hun" was not the fastest, but perhaps the deadliest when close enough to deliver the punch of its combined machine guns and cannon, better suite to very fast engagements rather than the British "spray and prey". It should be remembered however that statistically the main opponent of the me-109 (also credited with most victories) was the Hawker Hurricane. In raw engine power, the Merlin proved superior to the DB, with room to spare, still around 800 hp at 24,000 m while the Me 109 could climb higher but only developed 700 hp passed 25,000m. In terms if agility, the Me 109 roll rate proved superior, but was similar about 300 mph at 45°. According to Olivier Lefebvre (a noted authority on the Me 109), only a few E-4 received the DB601N (as E-4/N), considered quite troublesome. The bulk of the production and licences went to the DB601A.
Me 109F "Friedrich": The Luftwaffe workhorse in Africa and Russia.
Background of the Messerschmitt Me 109F
Development of a new airframe began in 1939 and from February 1940, an improved engine called the Daimler-Benz DB 601E was also developed to be coupled with this airframe. Messerschmitt engineers used both the engine and airframe on Bf 109 E-1 cells, the first two prototypes being named V21 (W.Nr 5602) and V22 (W.Nr 1800). They kept the trapeziform wing shape but with a reduced span (61 cm or 2 ft shorter). They in essence "clipped" the tips, which were no longer rounded and the most preeminent feature of the F-type. Also these wings incorporated a modified cooling system. V22 was thoroughly tested and became the testbed for the pre-production DB 601E serie. At first, the clipped wings had negative effect on the handling. So a third prototype, the V23 (W.Nr 5603), used reworked semi-elliptical wingtips.
This soon became the new standard for all future Bf 109 airframes. The fourth prototype V24 (W.Nr 5604) still had the clipped wings but with a new "elbow"-like supercharger air-intake. This too, went into production. There was also a deeper oil cooler bath beneath the cowling while aerodynamic studies led the fuselage to be cleaned up and the engine cowling modified.
About the nickname: "Friedrich" was not widely used, to say the least not recognized officially in any documentation. It seemed to have been used "by default". Only "Dora" saw wide use for the "langnase" version of the FW-190, the D-9. The Bf 109D never stick enough to gain it. it was a very different story with the Emil and Gustav, perhaps due to their wide use. The former was also much more popular than the latter, considered too heavy and lacking many amenities of the former ones. Albert Speer came in between and "total war" imposed drastic change in production with simplifications of design and widespread omissions.
Bf 109 F modifications, in detail
The Bf 109 F had many aerodynamic improvements, like the engine cowling smoother and more rounded, enlarged propeller spinner (borrowed from the Me-210) well-blended in the cowling. Underneath the nose was a more streamlined oil cooler radiator, and surrounding fairing, plus a new ejector exhaust arrangement. Late production models would have a metal shield placed over the left hand banks helping chase the fumes away from the supercharger air-intake. The latter was well-rounded, "elbow"-shaped. It helped it protruding in fact more out to gush more cold air for the more powerful engine.
The three-blade VDM propeller made in light alloy had an overall reduced diameter (3 m or 9 ft 8.5 in) and the pitch was now electrically set, regulated by a constant-speed unit, but with a manual override backup. In addition the standard 300 liter drop tank made its apparition. For all these changes, the Bf 109 F overall range was now set to 1,700 km (1,060 mi) (previously 660 km (410 miles) and 1,325 km (820 mi) with the drop tank).
The canopy had its forward lower triangular panel replaced by a metal panel, fitted with a port to fire signal flares, well needed in case of a crash. Nevertheless this was a gradual introduction and the F-1s and F-2s essentially never had this modification. Also, the pilot head was better protected b the addition of a two-piece armour plate (same as E-4). It was placed on the hinged portion of the canopy, and on top of that, a bullet-resistant windscreen was optional. More so, from 1942 onwards, pilots had retrofitted on these models a layered light-alloy plate aft of the pilot and fuel tank. To further enhance the pilot's safety, the fuel tank was self-sealing. These were cosmetic changes hardly seen from the exterior.
The tail section was redesigned, the rudder slightly reduced and the fin section took an airfoil shape, creating a sideways lift force swinging the tail slightly to the left, helping its effectiveness, and making the right rudder use on takeoff less useful to counteract torque effects from the engine. The old bracing struts were relocated below and forward, but not removed. The tail-wheel was now retractable and the main undercarriage legs were raked forward by six degrees, which helped greatly ground handling, for the pilot's great relief. It seems at the beginning the wing and tail section broke easily, so much so that JG 2 "Richthofen", Wilhelm Balthasar, was killed when trying the new fighter when his wings broke away.
Improvements following during production, with thicker wing skins, reinforced spars and for the tails failure it was shown they occurred because of high-frequency oscillations added to by vibrations from the engine, they resonated incrementally enough to cause a structural failure on the attachment point. Stiffening plates were added both sides, but the entire structure was soon reinforced, and later the entire wing was redesigned. Quasi-elliptical wingtips were adopted with a slight aerodynamic area reduction, but also new leading edge slats, shorter with an increased chord. Removable wingtips also slightly increased the span. They recovered also the plain ailerons of the previous models, for a 2R1 profile with a 14.2% ratio down to 11.35% and a dihedral 6.53°.
Always on the wings, radiators became shallower and moved back on the wing and in general cooling was redesigned, regulated by a thermostat making use of inlet and outlet flaps to procure the most efficient cooling depending on the speed. The new radiator was shallower and wider and fitted with a boundary layer duct for a better airflow. A link was established between the central flap to the lower split flap while the upper one lip position was regulated by an automated thermostatic valve (these valves were delivered as kits to the front). In additions, cutoff valves permitted the the pilot to shut down the wing radiator in case of damage, preserving the remaining coolant. They would eventually became standard on the Bf 109 G and K.
Armament modifications
On the Bf 109 F there were two synchronized 7.92 mm (.312 in) MG 17s capable of a rate of fire up to 500 rpg blended inside the engine cowling and the mandatory 20 mm Motorkanone cannon which fired through the propeller hub, probably its most deadly bite. However Adolf Galland criticized it as too light and Major Walter Oesau preferred his Bf 109 E, but on the same time, Werner Mölders saw the 20 mm centerline centerline Motorkanone as a real improvement, and the end, with its teething tail problems fixed, pilots started to lean more favorably towards the F series. For many it appeared as the best-handling so far, Mölders (plane SG+GW) flying one of the first operational Bf 109 F-1 in early October 1940 over UK possibly shoot down no less than eight Hurricanes and four Spitfires in about a week and clearly showed its potential if well-used.
Me109 F Variants
Me109 F-0/F-1/F-2 (?+208+1230=1448)
The pre-production F-0 were recognizable for their rectangular supercharger intake and had the 1,175 PS (1,159 hp, 864 kW) DB 601N engine, mated to a VDM 9-11207 propeller for a top speed of 615 km/h (382 mph). F-0, F-1, F-2 shared this early engine. The first had a centerline 20 mm MG FF/M Motorkanone with 60 rounds and flew in October 1940 (JG 51) over UK. Production of the F1 started in August 1940 and ended in February 1941. They had the same cannon and two 7.92 mm/.312 in MG 17 nose machine guns. The F-2 was armed with the 15 mm Mauser MG 151 cannon (200 rounds) and same nose MGs but some were retrofitted later with the new 20 mm cannon in the field. Production was 1,230 F-2s until August 1941. None were tropicalized although some F-2s received sand filters in the field later (F-2 trop). Another variant (canceled) was the F-2/Z high-altitude fighter fitted with a GM-1 boost, adopted for the F-4.
Me Bf-109F replica in Germany.
Me109 F-3 (15)
On the F-3 and F-4 the engine was now the planned 1,350 PS (1,332 hp, 993 kW) DB 601 E mated with a VDM 9-12010 propeller with broader blades for altitude, the engine being initially restricted but later cleared for service use from February 1942 onwards. This engine oddly used the 87 octane "B-4" aviation fuel while the previous F0/F1/F2 ran on more effective 100 octane "C-3" fuel, perhaps a signe of Germany's dwindling reserves already. The F-3 armament was the same centerline 20 mm cannon of the F-2 and usual pair of 7.92 mm (.312 in) MG 17s on the nose, but only 15 were ever produced. The sereie quickly swapped to the much more successful F-4.
Me109 F-4 (1941)
In addition to the new engine, the F-4 (Frontline June 1941) used the new Motorkanone 20 mm Mauser MG 151/20 (200 rounds), with a total production spanning just a year, between May 1941 and May 1942, and several sub-variants, some using additional 20 mm MG 151/20 wing cannons in faired gondolas. This option became available in field kits as the war progressed for the Me-190G and K in frontline service. These f-4 incorporated many of the above described wngs and tails, cooling later modifications. This was the last production version of the F-type, the rather less known of the whole serie. Indeed, the F-5, F-6 and F-8 were planned but never built as production swapped onto a much better G-type. Variants built were as follows:
Bf-109F evaluated by the South African Air Force
- F-4/R1 (240) with additional 20 mm wings gondola cannons
- F-4/R2 (5) recon version
- F-4/R3 (35) recon version
- F-4/Z (544)high altitude fighter with GM-1 boost
- F-4/Trop (576) Tropicalized version used by the Afrika Korps until 1943.
Me 109G "Gustav": The Messer strikes Back.
Design of the Messerschmitt Me 109G
The Bf 109 G series was in a nutshell, an F-serie keeping the same airframebut varying in detail with reinforced wing structure, a bullet-proof windscreen, coskpit canopy welded framing, and light armour on the fuel tank. Engineers at one point wanted to add small doors for the wheel wells (outer portion) and the bays were squared off. Also tne engine cowling received two small inlet scoops on spark plugs. Also, barely noticeable, the boundary layer bypass outlets on the upper radiator flaps. The new G-type or "Gustav" could be converted as a long range fighter bomber of reconnaissance plane ("Rüststand" or -R) in kits of pre-packaged parts (Umrüst-Bausätze) or (-U) and Field kits (Rüstsätze). Perhaps the less standard version was the special high-altitude interceptor using GM-1 nitrous oxide injection boost, pressurized cockpits and other modifications like the DB 605AS or D-series engine.
Perhaps the most important change in this G-Type was the new Daimler-Benz DB 605A engine. it was derived from the previous F-type DB 601E but with augmented compression ratio and many mass production simplification. So it was more powerful with a max output of 1,475 PS (1,455 hp, 1,085 kW) at 2,800 rpm when taking off. However the new engine had recurring teething issues by 1942, and the output was artificially capped by the bureau to 1,310 PS (1,292 hp, 964 kW) at 2,600 rpm only to emerge again on 8 June 1943 uncapped by a factory directive when all these problems were solved. This power unit was mated to a pre-1944 three-blade VDM 9-12087A variable-pitch propeller, 3 m (9.8 ft) large. It had broader blades and an electro-mechanical or manual-electric pitch. When 1944 began, a new propeller with even broader blades was introduced, fit for high-altitude interceptions, called VDM 9-12159.
There was quite an evolution during production, stepped up until 1944:
Early versions: Bf 109 F-4 with modified airframe
Spring 1943 (also nicknamed "The Bulge") production: Bulges in the cowling fitting of 13 mm (.51 in) MG 131 machine guns and on wings (larger tyres).
Late 1943: New clear-view cockpit, 30 mm (1.18 in) MK 108 cannon, new larger supercharger (DB 605AS) vertical stabilizer (G-5)
The G5 introduced also an enlarged wooden tail unit, and morticed balance tab, which required a counterweight at the front but improved ground handling a lot.
Early 1944: MW 50 engine power boost.
When introduced in numbers, the "Gustav" made quite an impression. Erich Hartmann, the 352 victories ace of aces only flew Bf 109G.
"It was very maneuverable, and it was easy to handle. It speeded up very fast, if you dived a little. And in the acrobatics manoeuver, you could spin with the 109, and go very easy out of the spin. The only problems occurred during takeoff. It had a strong engine, and a small, narrow-tread undercarriage. If you took off too fast it would roll ninety degrees away. We lost a lot of pilots in takeoffs"
Specific versions were:
-Long-range fighter-reconnaissance plane
-High-altitude interceptor. Both carried two jettisonable 300 L (80 US gal) drop tanks under the wing, pressurized cockpits and GM-1 nitrous oxide "boost" which raised the output by 223 kW (300 hp).
Gustav Variants
G1 February-June 1942 (167):
The first batch arrived in February 1942, already with a pressurized cockpit, and had a small, horn-shaped air intake above the supercharger intake, pilot's neck angled armour plate and small triangular armour-glass panels. Silica was added also to absorb moisture. TheG1 February-June 1942 (167):
last G1 batch of 80 G-1s were lightweight G-1/R2 with the GM-1 nitrous oxide 'boost' no neck armour and drop tanks fittings.
Me 109 G2 profile
G2 May 1942 - February 1943 (1,586)
The production started in May 1942. No cabin pressurization or GM-1 boost. Canopy back to the F-4 canopy armour. Top speed 660 km/h (410 mph) at 7,000 m (22,970 ft). Two Rüstsätze kits available, assigned at the factory, the G-2/R1 Long-range fighter-bomber (500 kg (1,100 lb) bely bomb) and jettisonable auxiliary undercarriage, modified fuel system and 300 L (80 US gal) drop tank. The G-2/R1 Long-range Fighter-bomber or JaboRei, was apparently only a prototype. The second, G-2/R2 reconnaissance aircraft with GM-1 and camera equipment, capable of 12,000 m (39,370 ft), and a ceiling of 13,800 m (45,275 ft).
Late production of the G2 included:
-Modified rack and internal fuel lines for 300 L (80 US gal) drop-tank
-Underwing 20 mm MG 151/20 cannon gondolas.
-ETC 500 bomb rack (250 kg (550 lb) bomb)
The African version called G-2 trop had a sand-filter forward of the supercharger intake and small fuselage metal brackets below the cockpit sill used as mounts for... sun umbrellas to shade the cockpit.
G3 September 1942 (50)
This was a pressurized version, similar to the G-1 but fitted with the same G-4 FuG 16 VHF radio set
G4 January - February 1943 (1242)
This model inaugurated the new FuG 16 VHF radio set (better clarity, three times the range), fuselage antenna lead-in moved further aft, larger 660 × 160 mm (26 × 6.3 in) mainwheels, more fuselage frames, altered fuselage legs nearly upright on the wheeltrain, new teardrop-shaped fairings over the wheel-wells, larger 350 × 135 mm (14 × 5 in) tailwheel with no recess. Sub-variants included the G-4/R2 Reconnaissance fighter, G-4/R3 Long-range reconnaissance fighter, G-4 trop Tropicalized fighter, G-4/U3 Reconnaissance fighter and the rare G-4y Command fighter.
Me 109 G6 profile
G6 February 1943 - ??mid 1944 (12,000)
The G-6 was fitted with nose 13 mm (.51 in) MG 131s, making the famous "Beule" or gun breeches bulges. The drag costed about 9 km/h (6 mph). Armament tests and modifications included the Werfer-Granate 21 BR 21 (Bordrakete 21 cm) heavy calibre rocket system, consisting of a jettisonable tube under each wing firing a 40.8 kg (90 lbs) warhead rocket coupled with the Revi reflector sights, spin-stabilized, 1,200 meters range, used against Allied bomber formations. The G-6/U4 used the 30 mm (1.18 in) MK 108 Motorkanone. Many armament kits were also available, underwing gondolas fo MGs, or fittings for bombs, drop tank, rockets.
Sub-variants included the G-6/R2 Reconnaissance fighter, with MW 50, G-6/R3 Long-range reconnaissance fighter (tow 300 L underwing droptanks), G-6 trop, G-6/U2 (GM-1 booster), G-6/U3 Reconnaissance fighter, G-6/U4 with the 30 mm/1.18 in MK 108 Motorkanone cannon, G-6y Command fighter, G-6/AS High-altitude fighter with the DB 605AS engine, G-6/ASy high-altitude command fighter, G-6N night fighter (Rüstsatz VI: 2x underwing MG 151/20 cannons, optional FuG 350Z Naxos, G-6/U4 N with the 30 mm/1.18 in MK 108 Motorkanone.
G5 May 1943 - August 1944 (476)
This was a pressurized cockpit variant of the G-6. Its AS sub-variant was the high-altitude boosted DB 605AS engine with GM-1 fitted version being called "/U2" and aerodynamically cleaner engine cowl.
G14 July 1944 (5,500)
The very late G-6 had a taller wooden tail unit, redesigned rudder with an inset improving stability, WGr. 21 cm (8 in) under-wing rockets and 30 mm (1.18 in) MK 108 cannon. Aileron Flettner tabs radio-navigation Y-Verführung (Y-Guidance) associated with the FuG 16ZY also made an apparition. By early in 1944 engines like the DB 605AS had superchargers or the MW-50 water injection with the DB 605AM which combined both features.
Top speed jump from 530 km/h (320 mph), sea level to 640 km/h (391 mph) at 6,600 m (21,650 ft) at high altitude. When the Normandy Landings occurred in June 1944, the G14 arrived as an attempt to design a standard with all modifications brought up since the introduction of the G-6, together with a variants fest also complicated by decentralized mass production as organized by Albert Speer. Metal was replaced by plywood wherever possible however.
Standardization did not worked (it as realized fully with the K type) but this Me 109 offered a whole range of improvements from the MW 50 power boosting water injection, Erla Haube 665 km/h (413 mph) high-altitude speed. The G-14/AS which had the DB 605ASM went even further with a 680 km/h (422 mph) at 7.5 km (24,600 ft) top speed high up. This model was also declined into the G-14y command fighter and U4 featuring the new 30 mm/1.18 in MK 108 Motorkanone.
Me 109 G-14 profile
G10 December 1944 (2,600)
Also nicknamed the "Erla Bastard", this decentralized Me 109G combined a regular G-type airframe with the DB 605 D-2 engine just to maintain production until the K-series kicked out of factories in numbers. Therefore airframes had to follow. The G10 apparently made its debuts in November 1944, right from Erla, WNF and Messerschmitt Regensburg factories. But their airframes could be traced thanks to two data plates, as G-14s diverted to a G-10 assembly line.
Modifications included the three-panel Erla-Haube, a new clear-view canopy eliminating the older rear fixed canopy section. Outside a 2,000 W generator, DB 605 D-2 power unit of the 109K, there was a standardised streamlined engine cowlings as well as standard MW-50 booster, larger Fo 987 oil cooler sunk unto a deeper fairing, enlarged crankcase, modified oil lines, small exhaust blister fairings (lower engine cowlings). Erla-built planes however had still the little bulges cowling, most distinguishing feature between G-10 factory planes. Also the radio antenna mast gave way to a swept-forward antenna (from the Me 163B Komet). Variants included the R2 Reconnaissance fighter, R6 Bad-weather fighter (PKS 12 autopilot), and U4 with the 30 mm/1.18 in MK 108 Motorkanone.
G-8/G-12 December 1944 (400?)
The G-8 was a special reconnaissance version was armed with the sole Motorkanone or alternatively the cowling machine guns to save weight, and was degraded further into short and long-range versions and several sets of cameras and radios depending on the mission. The G-12 was a small production two-seat trainer, a late conversion of wear out G-4/G-6 airframes, and by reducing the internal fuel capacity to 240 L with a drop tank in standard to save a seat. Two cowling machine guns, some times only one were the norm and the rear cockpit canopy was bulging out to leverage the instructor's seat behind the student pilot, both having the same basic instrument panel and all flight controls.
Rüstsatz Kits & Umrüst-Bausatz
Next, there are the Rüstsatz Kits like the R I which had an underbelly ETC 501/IX b bomb capable of carrying a SC 250 or SD 250 type 250 kg (550 lb) bomb. The R II or ETC 50/VIII d bomb rack was capble of handling four SC 50 type 50 kg (110 lb) bombs while the R III (Schloß 503A-1 rack) hold a belly drop tank of 300 L. Next the R IV had two 30 mm (1.18 in) Rheinmetall-Borsig MK 108 underwing gunpods and the R VI 20 mm Mauser MG 151/20 pods.
The Umrüst-Bausatz (Umbau) numbers included the U1 prototypes featuring a reversible-pitch propeller air brake, coversions to the U2 standard with a GM-1 boost and MW-50 boost, U3 Reconnaissance conversion giving later the G-8 production variant and the U4 featuring a 30 mm (1.18 in) MK 108 Motorkanone.
Me 109 G10 profile
Operational History
The G was probably the most famous and prolific version of all, with about 24,000 made in all (although RLM exact figure stays ellusive to say the least on these series) and cumulated more aerial kills than any other aircraft of World War II or in history so far. The bulk of these occurred against poorly trained, organized and equipped Soviet Air forces in 1941, with 21,200 kills in the span of the summer with E and F types, half in the air, the others on the ground.
In the latter part of the war, daily bombing raids supplied the G with many easy targets for the Luftwaffe, driving the move towards high altitude capabilities. And losses accumulated steadily until the USAAF deployed the P51 Mustang and found the right tactics. Thirteen pilots scored more than 200 kills altogether and the same group was credited with a total of nearly 15,000 kills during the war, all aces head and shoulders well above all allied or axis equivalents. In fact some aces that became aces during the Spanish civil war managed to survive the war, like Adolf Galland, which had quite a nice career with NATO.
No official "ace" status existed in the Luftwaffe but rather "Experte" for veterans and more than 2,500 Luftwaffe fighter pilots were aces according to the classic ww1 definition, more than 5 confirmed kills. The Finnish Bf 109Gs victory ratio rose as high as 25:1. The Italians too flown the Bf 109 with success, as well as Romania, Hungary, Bulgaria. The huge availability of the plane made them suitable for all sorts of combat mission, from regular patrols at mid-altitude to high altitude bomber interception, ground attacks or reconnaissance. The G version was probably the most preferred among pilots, flying it until the very last day of the war, as the new Type K sacrificed a lot to mass production and was less refined, also with often more inexperienced pilots.
Me 109K "Kürfurst"
The last Me 109.
Specifics of the Bf 109K
The type K was the last version of the Me-109. Indeed, postwar models like the Avia S199 and Spanish Buchon were so different that they are in no way related to the M109 line, with band new engines and tons of modifications.
The Bf 109K was multiplication of kits and sub-variants of past F and G series, factory and field conversions which eventually made production and maintenance not only overly complicated but also costly, a real problem for production management Germany ill-afford late in the war. The RLM, under Alber Speer orders, summoned Messerschmitt to rationalise its production and take all improvements to produce a standard model interchangeable parts and equipments, making the production cheaper and faster.
Messerschmitt Me-109 G-10 Eskorte
The RLM also pointed out the flaws in the airframe design and ordered these to be fixed for good. This process started in the spring of 1943, the prototype bing ready by autumn. Production started in August 1944, from the K-4 model (only mass production version, until the end of the war), the former pre-series nit equipped yet with the new Mercedes DB 605D engine. Deliveries from October 1944 reached 534 planes by main Messerschmitt A.G. plant at Regensburg (November), 856 in the end of 1944, for a total of 1,593 by the end of March 1945. This was a high rate of production despite allied bombings and continuous fighting. In fact only 314 K-4s were listed on active duty by the end of January 1945. Not all units would receive the Bf 109K.
Modifications of the Bf 109 "Kürfurst"
Externally, there were changes on the fuselage:
-Radio equipment hatch, moved forward and higher and D/F loop moved aft of the frames three and four.
-The filler point for the fuselage fuel tank replaced between frames two and three.
-Small circular plate above the footstep deleted
-Rudder fitted with the Flettner tab and fixed tabs.
-Long retractable tail wheel with two small clamshell doors was added.
Also there were changes in the airframe:
-Large rectangular fairings for the new larger main wheels.
-Small wheel well doors (outer ends of the wheel bays
-Radio equipment FuG 16ZY and relocated main swept-forward radio antenna
-FuG 25a Erstling IFF system
-FuG 125 Hermine D/F equipment
-Oxygen bottles relocated from the rear fuselage to the right wing.
-Flettner tabs for the ailerons (for some)
Messerschmitt Me-109K-4 blueprint
Armament
The K-4 had the now accepted 30 mm (1.2 in) MK 108 Motorkanone (MG 151/20 as the Motorkanone for some), fed by 65 rounds. Unfortunately it often jammed while manoeuvring in battle. There were still however the use of the two 13 mm (0.51 in) MG 131s (nose) rated for 300 rpg. The coscpit was fitted with Revi 16C reflector sight. The EZ 42 Gyro gunsight planned was never installed. Also, additional Rüstsätze or kits still existed:
-300 L (80 US gal) drop tank rack RIII
-500 kg (1,100 lb) bomb rack RI
-BSK 16 gun-camera, left wing. RIV
-Underwing 20 mm Mauser MG 151/20 cannon gondola pods RVI
-21 cm (8.3 in) Wfr.Gr. 21 rockets (mostly used by III./JG 26)
Powerplant
The Daimler-Benz DB 605 DB/DC engine was introduced with the K-4, although the very first batch was still given the the earlier DM. This new engine had an adjusting screw, for using either B4 + MW 50 Methanol Water injection equipment or C3 fuel (DB 605 DB) with an optional MW 50 (DB 605 DC) booster. By combining the moderately high-octane B4 fuel with the MW 50, an emergency power rat of 1,600 PS at 6,000 m was reached, also traduced by a take-off power of 1,850 PS. The DB could run on higher octane C3 fuel but in that case, without the MW 50 booster. With that C3 fuel and booster however the engine can potentially rate as high as 2,000 PS, but it was restricted or forbidden.
Nevertheless, using the MW 50 at maximum boost power, the Bf 109 K-4 became the fastest of the serie, reaching 710 km/h (440 mph) at 7,500 m (24,600 ft).
Messerschmitt Me-109K squadron in 1945 (Bundesarchiv)
Standard speed was 670 km/h (416 mph) at 9,000 m (30,000 ft) with an initial Rate of climb of 850 m/min without MW 50. This engine was mated to a wide-chord, three-bladed 3 m (9.8 ft) wide VDM 9-12159A propeller, the same as the previous G-6/AS, G-14/AS and G-10. Despite its excellent performances however, the 109 K-4 did not fare as well as previous G types which still had the privilege of veteran pilots, a rare occurrence in 1944-45. But the excellent performances of the 19 K did compensated a little for thes inexperienced rookies that were the former Hitler's youth that were trained on gliders and came of age. This was this abundance of novice, pitted against now largely allied veterans that caused such losses, just like for Japan.
Sub-variants
Most stayed as paper projects, up to experimentation is subjected to debate. The K-6 had on paper a completely revised armament, two 13 mm (.51 in) MG 131 above the engine hood, 30 mm (1.18 in) MK 108 Motorkanone but also an wings-mounted MK 108, substituted by 20 mm MG 151/20s. Armour weight was also increased to 90 kg (200 lb). Apparently prototypes tested at the Erprobungstelle Tarnewitz centre (Baltic coast). Perhaps the most advanced was the K-14, high-altitude heavy fighter with reinforced airframes (some delivered to II./JG52, Major Wilhelm Batz, late spring 1945). They only retained their 30 mm (1.18 in) motorkanon was to be fitted with a two-stage supercharged DB 605L engine and a four-bladed propeller. Top speed was to be 760 km/h (470 mph) at 12,000 m (39,000 ft).
- K-0 Pre-production, with the DB 605DM engine
- K-2 proposed with no pressurized cockpit version
- K-4: Serial production version - Pressurized cockpit, DB 605DM/DB/DC engine
- K-6 proposed heavy fighter version: reinforced wings,2x 30 mm MK 108 cannons, armour
- K-8 proposed reconnaissance version (like G-8)
- K-10 proposed version as K-6 but with MK 103M motorkannone
- K-12 proposed version, two-seat trainer
- K-14 proposed version, K-6, powered by a DB 605L engine