Heinkel He 274

infobox Aircraft
name =He 274
type =High altitude heavy bomber
manufacturer =Heinkel


caption =
designer =
first flight =December 1945
introduction =
retired =
status =
primary user =Luftwaffe
more users =Armée de l'Air
produced =
number built =2
unit cost =
developed from =Heinkel He 177
variants with their own articles =Heinkel He 277

The Heinkel He 274 was a four-engined bomber aircraft designed during World War 2 as a high altitude variant of the Heinkel He 177 for the German Luftwaffe. Normally a major new version would be numbered by adding 100 to the original model number, but the Heinkel He 277 was yet another different version of the He 177. The main difference between the He 274 and the He 177 was the abandoning of the twin coupled engine arrangement in favor of four independent turbocharged units, an extended fuselage with a modified wingspan, and twin fins and rudders.

Originally designated He 177A-4 in 1941, the He 274 was a high-altitude development of the He 177A-3. The He 274 dispensed with coupled engines in order to provide room for the installation of DVL exhaust driven TK 11B turbo-superchargers. The He 274 featured a pressurized compartment for a crew of four, this employing double walls of heavy gauge alloy, hollow sandwich-type glazing and inflatable rubber seals, a pressure equivalent to that at 2,500 m (8,200 ft) being maintained at high altitude. Defensive armament was restricted to a single forward firing 13 mm MG 131 machine gun and remotely controlled dorsal and ventral gun turrets each containing a pair of 13 mm MG 131 machine guns and directed from a blister in the roof of the flight deck or the rear of the ventral gondola. While originally considered a version of the He 177A bomber, the growing incompatibility of parts led to the redesignation to He 274. By 1941, Heinkel was engrossed by other urgent projects that left the company seriously short of detail design capacity. The He 274 project was therefor reassigned to SAUF at Suresnes, France.

Construction of the two prototypes, the He 274 V1 and V2 did not commence until 1943. They were to have been built in France by SAUF at Suresnes, France, but the prototypes were never completed in time. The He 274 V1 was being readied for flight testing at Suresnes in July 1944 when the approach of Allied forces necessitated the evacuation of Heinkel personnel working on the project. Minor difficulties had delayed the flight testing and transfer of the aircraft to Germany, and orders were therefore given to destroy the virtually completed prototype. Only minor damage was actually done to the airframe of the He 274 V1, and repairs were begun after the Allied occupation. The He 274 V1 was repaired by Ateliers Aéronautiques de Suresnes and used by the Armée de l'Air for several years as a high-altitude research plane. It was renamed the AAS 01A. Proposals to finish the uncompleted He 274 V2 were not to see fruition. The AAS 01A was eventually broken up in late 1953.

Operators

*
** French Air Force
*
** Luftwaffe

pecifications (He 274 V1)

aircraft specifications/switch
plane or copter?=plane
jet or prop?=prop
ref=
crew=4
capacity=
length alt=23.80 m
length main=78 ft 1¼ in
span alt=44.19 m
span main=145 ft 0 in
height alt=5.50 m
height main=18 ft 0½ in
area alt=170.00 m²
area main=1,829.86 ft²
airfoil=
empty weight alt=21,300 kg
empty weight main=46,958 lb
loaded weight alt=
loaded weight main=
useful load alt=
useful load main=
max takeoff weight alt=38,000 kg
max takeoff weight main=83,776 lb
more general=
engine (prop)=Daimler-Benz DB 603A
type of prop=12-cylinder inverted-vee engine with turbocharger
number of props=4
power alt=1,305 kW
power main=1,750 hp
power original=
max speed alt=580 km/h at 11,000 m
max speed main=360 mph at 36,090 ft
cruise speed alt=
cruise speed main=
never exceed speed alt=
never exceed speed main=
stall speed alt=
stall speed main=
range alt=3,440 km
range main=2,137 miles
ceiling alt=14,300 m
ceiling main=46,920 ft
climb rate alt=237 m/min
climb rate main=780 ft/min
loading alt=
loading main=
thrust/weight=
power/mass alt=
power/mass main=
more performance=
armament=
* 5 × 13 mm MG 131 machine guns in nose, dorsal, and ventral barbettes
* up to 4,000 kg (8,818 lb) of disposable stores in two internal bomb bays
avionics=

ee also

aircontent
related=
* Heinkel He 177
similar aircraft=
* Heinkel He 277
sequence=
lists=
* List of World War II military aircraft of Germany
* List of military aircraft of Germany
* List of WW2 Luftwaffe aircraft prototype projects
see also=

References

;Notes;Bibliography
*"Jane's fighting aircraft of World War II". Studio Books, 1989.
* Green, William. "Warplanes of the Third Reich". London: Macdonald and Jane's Publishers Ltd., 1970 (4th Impression 1979). ISBN 0-356-02382-6.
* Gunston, Bill & Wood, Tony. "Hitler's Luftwaffe". London: Salamander Books Ltd., 1977. ISBN 0-86101-005-1.