Heinkel: монопланы серии HE

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   Самолет HE 6 разрабатывался как машина для доставки почты. Были собраны и варианты его как гидросамолета, на которые ставили двигатели BMW VI и Packard.
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Flight, November 1928

BERLIN AERO SHOW 1928

The Heinkel Machines

   Of the two machines exhibited by the Heinkel aircraft works of Warnemunde, the seaplane was, perhaps, the more interesting, as it represented Dr. Heinkel's solution of a long-distance machine intended for transoceanic flights. The H.E. 10 was, in fact, the type with which an unsuccessful attempt was made last summer to fly from Germany to America, via the Azores. In our issue of October 11 we published a photograph of the Heinkel stand, and to this photograph we would refer readers for an illustration of the Heinkel H.E. 10 seaplane.
   The H.E. 10 is a typical Heinkel machine in that it is a low-wing monoplane, with the wings braced by struts to the two floats. But little change has been made in the fuselage design to adapt the machine to long-distance work. The addition of a sort of "conservatory" roof over the cockpits is the most notable alteration. Otherwise the machine is of perfectly normal - some might even say old-fashioned - Heinkel design. It seems likely that the machine is very efficient aerodynamically, the wings being of fairly large span and the fuselage of relatively small cross-sectional area, and of fairly good form. The H.E. 10 is, in fact, a logical development on a larger scale of the types of Heinkel monoplanes produced by this German designer, both by his present firm and previously by the Hansa-Brandenburg Company.
   The H.E. 10 is of mixed construction, in that its fuselage is a welded steel tube structure in which no wires are employed, while the monoplane wing is of wood construction. The wing has two box spars of normal type, with spruce flanges and three-ply webs. The leading edge is plywood-covered, as is also the lower surface from strut attachments to fuselage. The latter is necessitated by the presence of fuel tanks in the wings.
   In the forward part of the fuselage the engine mounting is built in as a self-contained unit. Behind the fireproof bulkhead is the "cabin," in which the seats (normally three, but with a possible fourth) are arranged one behind the other along the port side. The machine can be turned into a four-seater, in which case the extra seat is to the right of the last of the regular seats.
   The engine is a B.M.W. VI with propeller reduction gear, and as the petrol tanks are mounted in the wing, engine-driven petrol pumps are used for forcing the fuel to the service tank.
   The floats are of wood construction, with a single step. The step itself is perfectly flat, but the bottom aft of the step gradually changes into a vee, and then narrows to a point on the heel of the float. Horizontal struts join the floats, and the supporting struts form a letter "M" as seen from in front. From the outer and lower ends of the limbs of the "M" struts run to the wings.
   The main characteristics of the Heinkel H.E.10 are: Length o.a., 13-10 m. (43 ft.); wing span, 18-40 m. (60-3 ft.); wing area, 60-93 sq. m. (656 sq. ft.). Tare weight, 2,490 kg. (5,475 lbs.); permissible load, 2,320 kg. (5,100 lbs.); total loaded weight, 4,810 kg. (10,575 lbs.). The machine being designed for long-distance flights, the normal load of 5,100 lbs. is made up as follows: Crew of four, 320 kg. (700 lbs.); petrol and oil for 15 hours at "normal" throttle, 1,800 kg. (3,960 lbs.); equipment, 50 kg. (110 lbs.); instruments, etc., 150 kg. (330 lbs.). Maximum speed near sea level, 185 km./h. (115 m.p.h.). Climb to 1,000 m. (3,280 ft.) in 12 mins.
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