The Messerschmitt development department received a directive in 1942 to begin work on a Zerstörer (destroyer, or heavy fighter). An earlier RLM directive of 1941 had tried to limit the amount of new designs coming from the major aircraft companies (to not disrupt the production lines with new aircraft), so it was decided to couple two Bf 109 fuselages together, along with a new center wing and tailplane section, to come up with the Me 109Z (Zwilling, or twin).
The Me 109Z prototype incorporated two Bf 109F-4 fuselages, joined with a new constant chord wing center section and parallel chord tailplane. Included also was the 109F-4 powerplant, the Daimler Benz DB 601E-1 engine (12 cylinder, liquid-cooled, inverted V - 1750 horsepower on takeoff). The main landing gear attachment point were moved inboard to attach to a strengthened centerline keel in each fuselage. The outermost main landing gear retracted outboard; the inner legs retracted into the new center wing section. A single pilot sat in the port cockpit and the starboard cockpit was faired over. Armament on the projected production models varied (see below).
Several other Me 109Z designs were planned, developed around the 109G fuselages. The Me 109Z was to use around 90% of pre-existing 109 parts, with only the new main wing and tailplane, modified landing gear mountings, slightly larger wheels, extra fuel tanks in place of the starboard cockpit and a few other components needed to complete the aircraft. A prototype was completed in early 1943, but it was damaged in an Allied air attack on the Messerschmitt test center, and the damage was deemed too severe for repair. The development was abandoned in 1944, and by then, the Me 262 jet fighter had taken wing. One interesting note: the North American aircraft company followed the same design (independently) to produce the P-82 Twin Mustang, which was two P-51 fuselages joined in a similar manner as the Me 109Z.
Max speed: 462mph/cruise speed: 352mph
Z-0 (1943)
A single Z-0 airframe was built using two standard F-4 airframes. It was destroyed in an air raid just before its completion. After its destruction the entire Me-109Z program was terminated.
Z-1 (project)
The Z-1 was a projected production version similar to the Z-0 but based on the G-5 instead of the F-4. Armament was to be 5 x MK 108.
Z-2 (project)
This was a bomber version with only 3 x MK 108 and a bomb load of 1100lb.
Z-3 (project)
The Z-3 was to have been powered by the Jumo 213 engine.
Z-4 (project)
This was a bomber version of the Z-3, also powered by the Jumo 213.
What Willie Messerchmitt had envisiond however was to have: 2 MK-108, 4 MK-131, 4 MK-151, and 2 MK-108 arming each Me-109Z. I agree that the Zwilling could have been an effective bomber killer if it could get through the fighter cover. I dont know much about the handling of the Z though but I dont think it would have done much against allied fighters.
The Me-309:
Type: Single-seat fighter
Origin: Messerscmitt AG
Models: V1 and V2
First Flight: June 1942
Service Delivery: None
Final Delivery: None
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Engine:
Model: Daimler-Benz DB 605B
Type: Inverted V12 liquid-cooled
Horsepower: 1,475
Dimensions:
Wing span: 11.04m (36 ft. 2¾ in.)
Length: 9.46m (31 ft. ½ in.)
Height: 3.45m (11 ft. 3 in.)
Wing Surface Area: N/A
Weights: (V1)
Empty: 3530kg (7,783 lbs.)
Maximum: 4250kg (9,371 lbs.)
Performance:
Maximum Speed: 733km/h (455 mph)
Initial climb: NA
Range: N/A
Service Ceiling: N/A
Armament: (V4)
Four 13mm Machine Guns
Two 20mm Cannon
Two 30mm Cannon
Avionics:
N/A
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Comments:
The 309 was originally designed to be the definitive successor to the 109. Innovative features included a pressurized cockpit, tricycle landing gear, and a retractable radiator. However, the 309 could be out turned by the Bf 109G and was judged inferior to the Fw 190D and never reached production. The Me 609 was to be a twinned version similiar to the P-82.