Heinkel HD 40

Heinkel HD 40
HD 40 / I (serial number 268, D – 1200 )
Type:	Newspaper and bomb plane
Design country:	German Empire
Manufacturer:	Heinkel
First flight:	1927
Production time:	1927/1928
Number of pieces:	3

The Heinkel HD 40 was a German cargo plane developed for the transport of newspapers in the 1920s by the Ernst Heinkel Flugzeugwerke in Warnemünde . The abbreviation "HD" stands for "Heinkel Doppeldecker".

development

After the positive experience with the operation of the HD 39 newspaper plane , Ullstein Verlag commissioned two more from Heinkel in 1927, but they should be able to carry more freight. The design of the HD 40 was therefore kept somewhat larger and the hull was given a tubular steel frame for reasons of strength, in contrast to its predecessor, which was constructed entirely of wood. A more powerful BMW VI engine was also used. The two models built with the serial numbers 267 and 268 were given the company's internal designation HD 40 / I. Like the HD 39, they were given a striking black and yellow color scheme and the BZ lettering, the magazine they were supposed to carry. But before they could start their service, the first aircraft was destroyed on May 19, 1927 during the acceptance flights at the DVL in Berlin-Adlershof in a crash landing caused by an engine failure. The second HD 40 received the registration number on June 10 of that year D–1200, but broke the following month on July 27, also due to engine problems in Stettin.

A third copy, designated as the HD 40 / II with the work number 274, was made, but it was not ordered by Ullstein, but by the DVL and thus by the state. It was officially declared as a commercial aircraft, but was planned as a makeshift night bomber in the course of the covert rearmament of the German Reich. To this end, it was to be brought to the Soviet Union and tested in the secret German bases established there. The D–1180HD 40 was badly damaged when it was transferred to the Tomka base on July 15, 1928 under unspecified circumstances and was then makeshift repaired at the Aviation School in Lipetsk. In further use it is said to have been used in Tomka for the experimental spraying of chemical warfare agents and also in Lipetsk for testing aiming devices and devices for bombing. In April 1931 it was scheduled for a major overhaul in Germany. Whether and when this took place can no longer be traced. Finally, in September 1933, it was deleted from the register.

construction

The HD 40 is a heavily staggered, single-handle, tensioned double - decker in a wood-metal composite construction . The fuselage is formed by a tubular steel frame with a square cross-section, arched back and ending in a vertical edge towards the stern. The cargo hold (dimensions 1.2 m × 1.4 m × 1.0 m) with an expandable drop device is located directly under the pilot's cockpit, which is equipped with two adjacent seats. Behind this is the passenger cabin with dimensions of 1.8 m × 1.2 m × 3.0 m, which can accommodate up to six people.

The structure is made of wood and made up of two box spars, spruce straps and plywood webs. The planking between the spars, as well as the leading edge of the wing, is made of plywood, the remaining part is covered with fabric. Upper and lower wings are connected to each other by N-legs. The lower wing has a slight V-position of 2 °. The fuel tank with a capacity of 700 liters is located in the upper wing. The tail unit consists of a tubular steel frame covered with fabric and has balanced rudders and a horizontal stabilizer that can be adjusted in flight.

The axleless, rigid main landing gear has a track width of 3.36 meters. A grinding spur is attached to the stern.

Technical specifications

Three-sided tear

Parameter	Data
crew	2
Passengers	4-6
length	11.9 m
span	above 17.6 m below 15.15 m
height	4.92 m
Wing area	75.4 m²
Empty mass	2250 kg
Payload	1600 kg
payload	1000 kg
Takeoff mass	3850 kg
drive	a liquid-cooled, twelve-cylinder - four stroke - V engine
Type	BMW VI 5.5
Starting power nominal power continuous power	630 PS (463 kW) 600 PS (441 kW) on the ground 500 PS (368 kW) on the ground
Fuel volume	700 l
Top speed	163 km / h
Landing speed	85 km / h
Rise time	9.5 min at 1000 m
Summit height	3500 m with maximum payload
Flight duration	4.0 h

literature

• Volker Koos: Ernst Heinkel Flugzeugwerke 1922–1932 . Heel, Königswinter 2006, ISBN 3-89880-502-6 , p. 97/98 .

Web links

Commons : Heinkel HD 40  - Collection of images, videos and audio files

Individual evidence

1. ↑ HD 40 / II in the Civil Aircraft Register. Retrieved July 5, 2018 .