Washer SF 23

Washer SF 23
Washer SF 23A
Type:
Design country:	BR Germany
Manufacturer:	Scheiben-Flugzeugbau GmbH
First flight:	August 8, 1955
Number of pieces:	30th

Washer SF23C

The Scheibe SF 23 Sperling is a two-seater, mixed construction motorized aircraft that was developed and manufactured by the Scheibe-Flugzeugbau GmbH as a commercial aircraft.

The SF 23 was a simple conventional shoulder- wing aircraft with wings made of wood and a tubular steel fuselage covered with fabric. The first example (D-EBIN still with a 48 kW Continental A65 engine) had its maiden flight on August 8, 1955, still without approval. Approval for the sparrow was granted in mid-1958. It is characterized by its versatile uses. For example, simple aerobatics are just as possible as towing gliders and advertising banners. Another advantage are the STOL properties of the tail-wheel aircraft, which, however, require a bit of tact on the part of the pilots, as the “sparrow” often acknowledged operating errors with “tipping over” and “spinning”. For example, on February 22, 1959, two pilots with the D-EBIN were killed in Pocking for this reason. Take-offs and landings on short airfields are, however, easily possible. The SF 23 is reminiscent of the well-known Piper Cub, although the pilots of the SF 23 sit next to each other. As with the Piper Cub, it is a braced shoulder-wing wing, with the horizontal stabilizer also braced. The first version, the SF 23 A, did not yet have landing flaps and had to be landed using a side glide flight. It was not until the SF 23 A1 that landing flaps were fitted, which enabled an approach speed of approx. 90–110 km / h. The motorization took place with the Continental C90 , which developed 92 hp and thus ensured acceptable flight performance and a payload of at least 260 kg. It was also possible to convert the aircraft to series B (from 1960) or with a Lycoming O 235 to series C (from 1961) by installing a Continental or RR-O-200A engine, which improved flight performance even more and provided more power reserves, especially with regard to aerobatics and aircraft towing. The price of the machine at that time was around 23,500 DM. A total of 30 sparrows, including four in version B and six in version C, were built. In 2010 there were still a few “sparrows” to be admired in the sky and one more specimen was even transferred to the “B” series in cooperation with the Federal Aviation Office using EMZ SA1426.

After the development company was closed, the prototype support was taken over by the Scheibe Aircraft GmbH in Heubach, a company of the aviation company Sammet, which was founded especially for the further production of the SF 25 'Falke' .

Technical data SF 23

Parameter	Data
crew	2
length	6.20 m
span	9.87 m
Empty mass	approx. 475 kg
Max. Takeoff mass	approx. 730 kg
Cruising speed	170 km / h
Maximum speed (v NE )	250 km / h
Service ceiling	17,000 ft / 5,600 m
Engines	a Continental C90 , 92 hp
consumption	approx. 18 l / h

See also

• List of aircraft types

literature

• Gerd Zipper: Falkenhorst. The history of the disk planes . Weishaupt, 1999, ISBN 3-7059-0059-5 .

Web links

Commons : Disk SF 23  - collection of images, videos and audio files

• Type certification of SF 23 - EASA-TCDS-A.579 (PDF; 81 kB)

Individual evidence

1. ↑ ^{a b} FliegerRevue November 2009, pp. 54–57, Dittmar, Winter and Scheibe