The He-177, WWII Tactical and Technical Trends, No. 41, December 30, 1943 (Lone Sentry)

Although the He-177 bomber has been in the experimental stage for a considerable time, the first operational unit equipped with this type of aircraft has only recently been identified on the Western front. While some preliminary data were incorporated into a description of this plane published in Tactical and Technical Trends No. 6, p. 1, further details, based on additional material now available, appears pertinent at the present time.

The He-177 is an all-metal, cantilever midwing monoplane, about 64 feet long with a 103-foot wing span. The wings, which are set well back along the fuselage, have parallel inner sections and the outer sections taper in plan and thickness to elliptical tips. The metal stressed skin fuselage is rectangular in cross-section and the vertical tail unit comprises an angular single fin and rudder. The leading edge of the horizontal stabilizer is tapered and the tips are square. The wings are equipped with Fowler flaps and slotted type-dive brakes. The wheels of the double-wheel type landing gear diverge inboard and outboard of the engine nacelles to retract into wells in the wings. The tail wheel is also retractable.

While it gives the appearance of a twin-engine aircraft, the He-177 actually is powered with four motors. One version is equipped with two DB-606, 24-cylinder, liquid-cooled, inverted twin "V" engines. Each engine is made up of two inverted DB-601E units side by side, geared together with a clutch by which either unit can be cut out, driving one 4-bladed wooden propeller. This twin arrangement, if fully rated, generates 2,600 hp at 15,000 feet. Estimated maximum speed is 295 mph at 18,000 feet with DB-606's, and 300 mph with DB-610's. The service ceiling is estimated to be 21,000 feet with a normal load. Maximum ranges are believed to be 3,000 miles with a 2,200 lb-bomb load and 1,200 miles with 16,000 pounds. Eight wing tanks and one in the fuselage provide a total capacity of 3,711 U.S. gallons.

Calibers of the guns fitted have not been ascertained. Gun positions are observed in the nose, dorsal turret, lateral positions, base of nose, ventral position in gondola and the tail turret. One unconfirmed report indicates two 20-mm cannon in each wing, one M.K. 101 30-mm cannon centered in the nose, one 20-mm cannon in the ventral compartment and two 15-mm M. G. 151's in the tail turret.

The amount of armor plate carried is likewise in doubt, although the cockpit, engines and gun positions are probably protected.

The alternative bomb loads, which are stowed internally, vary considerably. They may consist of two 5,500-lb or four 3,960-1b, or two 3,960-lb and ten 550-lb or ninety six 110-lb bombs. In place of bombs, four to eight torpedoes may be carried and the number carried could be increased in the case of the 770-lb circling torpedo.

One version of the He-177 is believed to be fitted with a pressure cabin for long flights at high altitudes.

The aircraft carries a crew of seven or eight and is designed for long reconnaissance, long-range bombing, and torpedo attacks. It is particularly suitable for operations against convoys and has recently been used in such attacks both in the Mediterranean and Atlantic. This plane can carry the new radio-controlled glider bombs which are particularly designed for antishipping attacks. The length of time required for the development of this aircraft suggests structural or mechanical defects in the original design. Furthermore, the novel engine design may have necessitated considerable experimental work, both to reduce fire hazards and to produce a workable clutch arrangement which will permit one engine of each unit to be disengaged and restarted while the aircraft is in flight. Future employment of the He-177 should indicate to what extent these reported difficulties have been overcome.