Arado SI
Arado SI | |
---|---|
Type: | Trainer aircraft |
Design country: | |
Manufacturer: | |
First flight: |
January 1926 |
Production time: |
1925/1926 |
Number of pieces: |
3 |
The Arado SI is a German training aircraft from the 1920s and the first in-house development by the Arado Flugzeugwerke, founded in Warnemünde in 1925 .
development
In 1925, when Arado was founded, some samples were initially produced under license from Ernst Heinkel Flugzeugwerke , also based in Warnemünde . In the same year, the designer Walter Rethel switched from the Fokker plants to Arado and was the first to design the two-seater S I training aircraft. The prototype with the Lucifer engine and serial number 20 began testing in January 1926, the same as that for a training aircraft hoped for good-natured flight characteristics and visibility confirmed. During the construction, Rethel paid attention to simple repair and maintenance with easy access to the individual areas. The approval was granted the following July, the aircraft was acquired by the Reich Ministry of Transport and then handed over to the DVL in Berlin-Adlershof, where it was D–817
used for pilot training from February 1927 with the registration number . It was there that the Lucifer engine was replaced by a more powerful Sh-12 engine. After several changes of owner, the S I was D–ESEX
re-registered in 1934 .
The public presentation took place in 1927 during the sample fair in Milan .
The second model built and designated as S Ia (WNr. 21) received a Sh 12 from the start and was D–994
approved for the Staaken Aviation School in 1926 . It was only removed from the aircraft role ten years later. The third and last S I with the work number 22 found no buyers for a long time. Initially, it was supposed to be equipped with a 100 hp Mercedes engine, which, however, caused an unfavorable shift in the center of gravity and was therefore not used. Five years in the possession of Arado located it was finally in 1931 for only 850 ℛℳ to the Bachmann works sold part of Aero Sport GmbH, where their trail is lost.
construction
The S I is a cantilevered, unrestrained one -and-a-half-decker in a composite construction .
- hull
The fuselage consisted of a welded tubular steel frame with a rectangular cross-section, which was planked with sheet metal in the area of the engine and otherwise covered with fabric. The back of the fuselage behind the cabins was covered with a detachable, semicircular shell, which ensured easy access to the control mechanisms. The engine mount was designed to be pivotable downwards forwards, so that it was possible to change it without the aid of a pulley system when only two people were deployed. There was a fire bulkhead between the engine and the forward crew cabin. The S I was equipped with a double control system that could be deactivated by the flight instructor in the student cabin during the flight if necessary.
- Structure
The wings were made of wooden frames with two box spars, the front edges of which were made of birch plywood. The planking of the underside of the wing was also made of plywood, the upper surfaces were covered with fabric. While the upper wing was continuous, the lower wing consisted of two parts. The structure was connected to each other by V-supports and to the fuselage by two tensioning towers with N-struts in the canopy area. In the upper wing were the two brass fuel tanks with a total capacity of 150 l, suspended swinging on bands. Ailerons were only in the upper wing.
- Tail unit
The tail unit, supported by I-stems towards the fuselage, consisted of tubular steel frames covered with fabric. The horizontal stabilizer was adjustable in flight, the rudder not balanced.
- landing gear
The S I had a rigid, rubber-sprung main landing gear, the wheels of which were connected to one another by an axle. At the stern there was also a rubber-sprung grinding spur.
Technical specifications
Parameter | Data (SI) | Data (S Ia) |
---|---|---|
crew | 1-2 | |
span | above 11.50 m below 8.50 m |
|
length | 7.35 m | 7.44 m |
height | 2.85 m | |
Wing area | 26.5 m² | |
Empty mass | 600 kg | 615 kg |
Payload | approx. 300 kg | |
Takeoff mass | 915-920 kg | 935 kg |
drive | an air-cooled three-cylinder - four stroke - radial engine | an air-cooled nine-cylinder four-stroke radial engine |
Type | Bristol Lucifer | Siemens & Halske Sh 12 |
Starting power nominal power continuous power |
120 PS (88 kW) 100 PS (74 kW) close to the ground 80 PS (59 kW) close to the ground |
125 PS (92 kW) 112 PS (82 kW) close to the ground 108 PS (79 kW) close to the ground |
Fuel volume | 150 l | |
Top speed close to the ground |
140-147 km / h | 150 km / h |
Cruising speed | 120 km / h | |
Landing speed | 55 km / h | |
Rise time | 8 min at 1000 m altitude 19 min at 2000 m altitude |
k. A. |
Service ceiling | 4000 m | 4100 m |
Range | 500 km | |
Flight duration | 4 h | |
Take-off / landing runway | 55 m / 57 m |
literature
- Volker Koos: Arado Flugzeugwerke 1925–1945 . Heel, Königswinter 2007, ISBN 978-3-89880-728-9 , pp. 13/14 .
- Jörg Armin Kranzhoff: Arado. History of an aircraft factory . Aviatic, Oberhaching 1995, ISBN 3-925505-27-X , p. 15th ff .
- Helmut Stützer: The German military aircraft 1919–1934 . E. S. Mittler & Sohn, Herford 1984, ISBN 3-8132-0184-8 , p. 181 .