Before i start to work on the He-378, I built the He-274.
Heinkel He 274 A-3/R2
The story of the real He-274
Developed in substitution for the planned He-177 A-4 high-altitude bomber, the Heinkel He 274 might have been the perfect German WW2 Heavy bomber. Fitted with a pressure cabin, the aircraft was powered by four 1726Hp Daimler-Benz DB 603A-2 engines and featured a lengthened version of the He 177A-3 fuselage, with a new high-aspect-ratio wing and twin fins and rudders. Two prototypes were ordered in May 1943, together with four He 274A-0 pre-production examples, which were to have 1900Hp DB 603G engines. Despite an unsuccessful German attempt to destroy the almost-complete first prototype when they retreated from Paris in July 1944, the aircraft was finished by the French after the liberation and flown from Orleans-Bricy in December 1945 as the AAS 01 A. It was used later to test-fly models of such aircraft as the Aerocentre NC 270 and the Sud-Ouest SO 4000.
The significance of this design is that had this aircraft entered production and been used in operations over England it would have been impossible for Allied fighters to intercept over the target, owing to its extreme high altitude performance.
The model
What-if version: The He 274 A-3/R2
More images at:
http://www.flickr.com/photos/einon/http://www.brickshelf.com/cgi-bin/gallery.cgi?m=Einonhttp://www.mocpages.com/home.php/2564Development:
In 1941, with the EUA entering the war against Germany, the Germans soon found that they needed a long-range bomber to strike the American cities and then return to the occupied France. They needed the “Amerika Bomber”. Various companies were developing heavy bomber designs at this time, many of them were large four-engine aircraft proposals that showed promise as heavy bombers, like the Fw 300 from Focke Wulf, the He-274 from Heinkel, the Ju-290 from Junkers, and the Me-264 from Messerschmitt AG. Since four engines might not have been enough to reach New York, there were also some six engines proposals, like the Ju-390, the Ta 400 and the “Me-264B”, all of them capable of strike the American cities easily.
But all of these projects were expensive and would have taken lots of time to develop and build. But the Heinkel Company soon developed the He 274 A-2, a 12000km long-range bomber, using many components from the previous He 274 design and capable of becoming operational in just a few months.
The new version was soon entering production, with the first bomber squadron operational in May 1944, just before D-Day. In June of that year, 10 He-274 flew to New York, dropping less than 10 000kg of bombs over the city.
The mission eventually failed its ultimate goal, to scare the American population. 4 He-274 were shoot down during the return voyage and 3 crash in the Azores. The remaining 3 landed in France, being destroyed by the British air force on the next day.
The He 274 A-2 was therefore a high altitude long-range bomber, capable of flying at more than 15 000 meters, with a loaded range of 12 000km. It featured a pressurized compartment for a crew of four, a pressure equivalent to that at 2,500 m (8,200 ft) being maintained at high altitude.
Armament:
Normal defensive armament for bomber versions comprised a forward, remotely operated "chin turret" under the extreme nose with twin 20mm MG-151/20 cannons, one dorsal turret armed with a pair of MG-151/20 cannon, a ventral turret for lower rearwards defence with another pair of MG-151/20 cannon, and a remotely controlled HL 151V tail turret with a quartet of MG-151/20 heavy machine guns or four 13,2mm MG-131 heavy machine guns.
For anti-ship missions, the A4/R2 version carried guided missiles or guided bombs like the Hs-293 and the Fritz-X under the wings. Also, the forward pair of MG-151/20 was replaced with two MK 103 30mm cannons to attack enemy ships.
Later, for anti-tank missions, Luftwaffe forward maintenance units modified a small number of He 274s, fitting a 75 mm Bordkanone BK 7,5 cannon within the aircraft's undernose Bola gondola, with the long barrel protruding well forward, beyond the glazed "fishbowl" nose.
The plane had two internal bomb bays, which could be transformed into a giant single bay, capable of carrying the largest bombs available in Germany. The maximum bomb load was 10 000kg, 6 000 kg internal and the rest external in up to four hard points under the wings. Guided bombs, torpedos and missiles could be operated from the bombardier position, using an array of controls and guiding systems. However for long-range missions, a 2 000-3 000kg was more common.
Power:
Initially the plane would have had 4 Daimler Benz DB 406C propeller engines producing 3,500hp each, but the development of these engines had stopped in 1942 under orders by the RLM. Since a new engine was needed to power the bomber, it was decided to use the new Daimler Benz DB 109-021RT, a 4,000hp shaft turboprop version of the Heinkel-Hirth HeS 109-011 jet engine, which delivered 1,100kg additional thrust. The new engine had some initial problems, but they were soon solved, and became extremely reliable. Since the He 274 dispensed the coupled engines used on the He-177, more room was provided for the installation of DVL exhaust driven TK 11B turbo-superchargers, one per engine, for better power output at high altitude. A conventional, simple and stronger landing gear was used instead of the complicated landing gear used on the He-177. Two auxiliary Junkers Jumo 004 jet engines were installed under the wings in small pods. The jet pods greatly improved takeoff performance and dash speed over the target however, in normal cruising flight, these engines were shut down to conserve fuel.
To compare: B-29 x He-274
In some ways, the new bomber was comparable to the Boeing B-29 being developed at the same time in America. Both were designed to flight at extremely high altitudes away from the enemy fighters, drop their bombs, and then return to their bases. However, the B-29 was a heavier and eventually much slower plane, it carried a smaller bomb load (9 000kg vs. 10 000kg) and with a shorter range (9 000km vs. 12 000km).
The He-274 had therefore a far higher power to ratio than the B-29, being much more faster.
The B-29 was also a much more complicated plane, prone in its early service years to catastrophic engine fires, electrical failures, and other costly malfunctions, sharing many similar problems with the first versions of the He-177. On the other hand, the He-274 was much more simpler, it used lots of proven components and was much more reliable, thanks to its separate engines.
General characteristics
Type: High Altitude Strategic Heavy bomber.
Crew: 4 (pilot, second-pilot/navigator/gunner, bombardier and two gunners)
Length: 24,5 m;
Wingspan: 45,2 m;
Height: 5,7 m;
Empty weight: 24,200 kg;
Max takeoff weight: 43,000 kg;
Powerplant: 4 Daimler Benz DB 109-021RT turboprop engines (4,000hp + 1100kg additional thrust each) and 2 Junkers Jumo 004 jet engines.
Performance:
Maximum speed (with jet engines): 710 km/h at 12,000 m.
Crusing Speed (no jets): 600km/h at 12,000m.
Range: 12,440 km;
Service ceiling: 15,200 m;
Rate of climb: 242 m/min
Armament:
Bomber:
-> 12 20mm MG-151/20 cannons in 5 defensive turrets;
-> Up to 10,000 kg of disposable stores in two internal bomb bays and under the wings.
Hope you like it!
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http://www.flickr.com/photos/einon/http://www.brickshelf.com/cgi-bin/gallery.cgi?m=Einonhttp://www.mocpages.com/home.php/2564Eínon
