https://en.wikipedia.org/wiki/Koolhoven_F.K.58
The Koolhoven F.K.58 was a single engine, interceptor-fighter aircraft designed
and mainly manufactured by N V Koolhoven in the Netherlands under contract by
Battle of France.
with fighters quickly enough. The Dutch manufacturer Koolhoven was contracted to
design a cheap, easily built, high-performance fighter, that could be built and
serviced with French-supplied engines and other components. According to some
sources, the Koolhoven fighter was intended primarily for fighter units based in
French colonies.
On 17 July 1938, the prototype Koolhoven Model 1166 (later renamed the F.K.58)
design: the Fokker D.21. The F.K.58 used the same composite materials as the
D.21: the structure of the fuselage consisted of welded steel tubing covered
with sheet metal (front part) and fabric (aft); the wings had wooden members
with a plywood and fabric skin.
l'Air. Production was transferred to Nevers, where the aircraft were re-built
with French components and the extraneous parts were returned to the
In July 1939, the Dutch government placed an order on behalf of the Luchtvaart
Afdeling (Netherlands Army Aviation Corps) for 36 F.K.58 variants, powered by
Bristol Taurus engines. As the British government restricted exports of
Tauruses, they were to be replaced by Dutch stocks of the Bristol Mercury VIII
(as used by the Dutch Fokker D.21 and Fokker G.1A). The lower output of the
Mercury, relative to the Taurus, would have allowed a top speed to some 480
km/h.
The F.K.58s comprising the Dutch order were in various stages of construction
when they were destroyed by a German air raid on the Koolhoven factory in May
1940.
Role
Fighter
Manufacturer
Koolhoven
Designer
Erich Schatzki
First flight
17 July 1938
Introduction
1940
Retired
1940
Primary users
French Air Force
Polish Air Force
Produced
1939-1940
Number built
20
The F.K.58 was originally ordered to serve with AdA units based in French
overseas territories. Following the outbreak of war with Germany, however, the
type was assigned to an ad hoc, Free Polish air force unit commanded by Captain
Walerian Jasionowski. Roughly equivalent to a French escadrille, or Polish
eskadra, it was often known by the unofficial name "Eskadra Koolhoven". The
that defended rear areas against long-range bombers and other enemy aircraft, as
unit operated from the Salon and Clermont-Aulnat air bases.
By May 1940, 13 aircraft were operational with Eskadra Koolhoven. As delivered,
however, the fighters were unarmed and the Poles had to acquire machine guns and
fit them. From 30 May 1940, they were in service, patrolling firstly in the
Avignon-Marseille area, and then over Clermont-Ferrand. At least 47 operational
sorties were recorded, but the Escadron did not encounter enemy aircraft.
The type's service life was short-lived, with ; the unit had no confirmed
victories, but at least one F.K.58 was lost. After the fall of France, all
surviving airframes were scrapped.
Specifications (F.K.58)
General characteristics
Crew: One
Length: 8.7 m (28 ft 6.75 in)
Wingspan: 11 m (36 ft 1.25 in)
Height: 3 m (9 ft 10 in)
Wing area: 17.3 m2 (186.2 ft2)
Empty weight: 1,930 kg (4,255 lb)
Loaded weight: 2,750 kg (6,063 lb)
Performance
Maximum speed: 505 km/h (314 mph)
Cruise speed: 450 km/h (280 mph)
Range: 750 km (466 mi)
Service ceiling: 10,000 m (32,810 ft)
Rate of climb: 11.6 m/s (1,130 ft/min)
Wing loading: 159 kg/m2 (32.6 lb/ft2)
Power/mass: 0.28kW/kg (0.17 hp/lb)
Armament
4 x 7.5 mm FN-Browning machine guns in underwing fairings
*
|
|