Heinkel HD 20

Heinkel HD 20
Type:	Photo reconnaissance
Design country:	German Empire
Manufacturer:	Heinkel
First flight:	1926
Production time:	1926
Number of pieces:	1

The Heinkel HD 20 is a German aircraft from the 1920s, developed and built by the Heinkel works in Warnemünde .

development

The HD 20 still without registration on the Heinkel factory premises in Warnemünde (1926)

In 1926 the Reich Ministry of Transport commissioned Heinkel to produce a test photo reconnaissance aircraft for long distances, officially declared as an aerial photo and FT aircraft (FT for radio telegraphy ). The aircraft designated as HD 20 with serial number 251 was completed in the same year and approved as D-1157 , the registered owner was Albatros Flugzeugwerke . The aircraft was then transferred to the German Aviation Research Institute (DVL) in Adlershof . There is no further evidence to support this statement for a test mentioned in the literature and use for observer training at the flying school and test site in Lipetsk, Russia.

On a ferry flight from Warnemünde to Rechlin on 21 November 1929, the HD 20 had at because of problems with the left engine Reppentin emergency landing , taking on the bow came to stand and was heavily damaged. The pilot Hoppe was unharmed, but the HD 20 had to be written off.

construction

The HD 20 is a braced, untensioned and heavily staggered one and a half decker in a composite construction . The fuselage consists of welded steel tube with four longitudinal spars that form a rectangular cross-section, fabric covering, and ends in a cutting edge. In the bow there is the open observer's stand, behind it a cabin for the photo equipment and a floor hatch, to which the pilot's cockpit is connected. The back of the trunk is strongly arched.

The supporting structure is formed by the two-part, strongly offset wings of different spans . They consist of wooden frames with two box spars and ribs. The wing nose and the underside between the spars are clad in plywood, the remaining part is covered with fabric. The wings have a slight V-position, 1 ° at the top and 2 ° at the bottom. The upper wing is connected to the fuselage by a tombstone and a V-strut on each side with the lower wing, which in turn is connected to the fuselage by an N-strut. The engines and oil coolers are located on tubular steel struts above the lower wing in streamlined cladding made of removable aluminum plates. The fuel tank with a capacity of 450 l is housed in the upper wing.

The tail unit consists of a fabric-covered tubular steel frame. Rudder and elevator are aerodynamically balanced and adjustable in flight so that flight with only one running engine is possible. The undercarriage with a larger track width is not connected to one another and is attached to the fuselage by V-struts. The main wheels have internal suspension. A grinding spur is attached to the stern.

Technical specifications

Three-sided view

Parameter	Data
crew	2-3
span	above 12.80 below 8.80 m
length	9.45 m
height	3.52 m
Wing area	39.8 m²
Empty mass	1300 kg
Payload	655 kg
Takeoff mass	1955 kg
drive	two air-cooled nine-cylinder - four stroke - radial engines
Type	Wright Whirlwind with Aeron Reed two-bladed propellers made of metal with light metal hub covers
Take-off performance Combat and climb performance Nominal performance max. Continuous output	230 PS (169 kW) 210 PS (154 kW) close to the ground 200 PS (147 kW) close to the ground 170 PS (125 kW) close to the ground
Fuel volume	450 l
Top speed	191 km / h near the ground
Landing speed	83 km / h
Rate of climb	4.0 m / s
Rise time	4.2 min at 1000 m altitude 9.7 min at 2000 m altitude 15.36 min at 3000 m altitude
Summit height	4700 m with maximum payload
Use radius	570 km
Flight duration	3 h

literature

• Volker Koos: Ernst Heinkel Flugzeugwerke 1922–1932 . Heel, Königswinter 2006, ISBN 3-89880-502-6 , p. 53 .
• Volker Koos: Aviation between the Baltic Sea and Breitling . Warnemünde sea and land airfield 1914–1945. Transpress, Berlin 1990, ISBN 3-344-00480-8 , pp. 76 .
• Helmut Stützer: The German military aircraft 1919–1934 . E. S. Mittler & Sohn, Herford 1984, ISBN 3-8132-0184-8 , p. 37, 137 and 186 .

Web links

Commons : Heinkel HD 20  - collection of pictures, videos and audio files

Individual evidence

1. ^ Civil Aircraft Register - Germany. Retrieved August 23, 2018 . 
2. ↑ Stützer, page 137