Akaflieg Berlin B4 F.F.

B4 F.F.
Role	Light aircraft
National origin	Germany
Manufacturer	Akaflieg Berlin
Designer	Walter Stender, dr. Martin Schrenk and Gerald Klein
First flight	December 1931
Number built	1

The Akaflieg Berlin B4 F.F. was a single-seat aircraft built in Germany in the early 1930s. It was a high-wing monoplane of all-wood construction with fabric-covered foldable wings ^[1]

Design and development

In 1931 the Deutsche Luftfahrt-Verband e.V. (DLV) opened a competition for an inexpensive light aircraft. Two entries were put forward; Akaflieg Berlin's B4 F.F. (D-2229) and Dipl.-Ing. Hermann Mayer's MM-1 (D-2230), with both aircraft exhibited at the 1932 Deutschen Luftsport-Ausstellung (DELA) in Berlin. ^[2]

Like the Mayer MM-1 the B4 F.F. was constructed at the DLV workshops in Adlershof. Design took eight months and construction a further nine. ^[2]

Specifications (B4 F.F.)

Data from ^[2]

General characteristics

• Length: 5.7 m (18 ft 8 in)
• Wingspan: 9 m (29 ft 6 in)
• Height: 2.4 m (7 ft 10 in)
• Wing area: 10 m² (110 sq ft)
• Aspect ratio: 8
• Empty weight: 185 kg (408 lb)
• Gross weight: 285 kg (628 lb)
• Powerplant: 1 × Daimler F7502 , 15 kW (20 hp)
• Propellers: 2-bladed fixed-pitch propeller

Performance

• Maximum speed: 125 km/h (78 mph, 67 kn)
• Service ceiling: 3,500 m (11,500 ft)
• g limits: +8 (ultimate load factor)
• Wing loading: 28.5 kg/m² (5.8 lb/sq ft)
• Power/mass: 19.18 kg/kW (31.53 lb/hp)

References

1. Stender, Walter (April 1932). ""FF" Kleinflugzeug der Akaflieg Berlin". Flugsport (in German) (8): 149–151.
2. Wefeld, Hans Joachim (1995). 75 Jahre AKAFLIEG BERLIN 1920–1995 (in German). Akademische Fliegergruppe Berlin e.V. pp. 35–39.