| 145 km/h|
| 12 m|
K + W
The Häfeli DH-3 was a 1910 Swiss two-seat reconnaissance aircraft, built by the aircraft department of the Federal Construction Works (Eidgenoessische Konstruktionswerkstaette, (K+W)) at Thun, Switzerland.
Häfeli DH-3 Wikipedia
Following the poor performance of the DH-2, August Häfeli designed an improved version the Häfeli DH-3. It was basically the same airframe as the DH-2, the upper wing had a cutout to give a greater field of fire for the pivoting machine gun. It was a two-bay aircraft of wood and fabric construction, powered by a 120 hp (89 kW) Argus As II water-cooled inline engine. Initial problems with the landing gear and the engine cooling system led to modifications. Further developments were the re-engined and improved DH-3a, and the DH-3b used for engine trials. Following successful trials with an installation of the Handley Page slats all surviving DH-3as were modified in 1932.
On 8 January 1919 a DH-3 inaugurated the first Swiss air mail service between Zurich and Berne. A DH-3 aircraft failed a structural test in 1923 which caused the DH-3 to be withdrawn from service. The DH-3a, following modification, remained in service until 1939.DH-3
Initial production version with Argus As II engine, 24 built.
Improved version with Hispano-Suiza HS-41 8Aa engines, four aircraft ordered in 1919. A second order for 30 aircraft was placed in 1919 with license-built engines, a third order for 49 aircraft being placed in 1925. Survivors were modified at Thun in 1932 with Handley Page slats and changes to allow crew to wear parachutes.
Three aircraft powered by the indigenous 150 hp (112 kW) LFW 0 engine developed by the Swiss Locomotive and Machine Works were built in 1918.
Swiss Air Force
Data from The Illustrated Encyclopedia of Aircraft (Part Work 1982–1985)
General characteristicsCrew: two
Length: 26 ft 1 in (7.95 m)
Wingspan: 41 ft 0 in (12.50 m)
Height: 10 ft 2 in (3.10 m)
Wing area: 409.04 m² (38 m²)
Empty weight: 1,587 lb (720 kg)
Max. takeoff weight: 2,447 lb (1110 kg)
Powerplant: 1 × Hispano-Suiza HS-41 8Aa 8-cylinder Vee piston engine, 150 hp (112 kW)
PerformanceMaximum speed: 90 mph (145 km/h)
Range: 249 miles (400 km)
Service ceiling: 14,765 ft (4500 m)
Armamentone pivoted machine-gun in the rear cockpit