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).
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. The
G1 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
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 109 G-10 model