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The LWD Żak was a Polish touring and trainer aircraft of the late 1940s, designed in the LWD and built in a short series.

LWD Żak
Role	Touring and trainer aircraft Type of aircraft
Manufacturer	LWD
Designer	Tadeusz Sołtyk
First flight	23 March 1947
Introduction	1947
Retired	1955
Primary user	Polish civilian aviation
Produced	1947-1948
Number built	13

Design and development

The Żak (old-fashioned "student") was designed in the Lotnicze Warsztaty Doświadczalne (LWD, Aviation Experimental Workshops) in Łódź, directed by Tadeusz Sołtyk in 1946, as one of the first Polish post-war aircraft. It was a light low-wing cantilever monoplane of a mixed construction, with a crew of two, sitting side by side, and fixed conventional landing gear. The first prototype Żak-1 was first flown on March 23, 1947. It was powered by the Czechoslovak 65 hp straight engine Walter Mikron III and carried markings SP-AAC. The second prototype Żak-2 was powered by the 65 hp flat engine Continental A-65 and had an open cockpit. It was flown on November 27, 1947, and carried markings SP-AAE.

The design appeared successful and the Ministry of Communication ordered a series of 10 aircraft. They were to be powered by licence-built A-65 engines, but since plans of engine production were abandoned, it was decided to fit them with Walter Mikron engines. They were also fitted with a closed canopy, sliding rearwards, and named Żak-3. Ten planes were built by the LWD in the end of 1948, the first of them was flown on November 8, 1948. They had markings: SP-AAS to SP-AAZ, and SP-BAA to SP-BAC. At least one (SP-AAX) had engine replaced later with 85 hp (63 kW) Cirrus F.III. They were used in the Polish regional aero clubs until 1955.

On October 20, 1948, there was flown a prototype of the last variant, Żak-4, meant for a glider towing. It had stronger 105 hp Walter engine and an open canopy. Since it showed unsuitable for glider towing, and old Polikarpov Po-2 appeared the better plane for this purpose, Żak-4 was not built in series, and the prototype was re-fitted with a closed canopy and used as a touring plane in aero club (markings SP-BAE).

Variants

Żak-1 (SP-AAC)

The first prototype powered by Walter Mikron III engine.

Żak-2 (SP-AAE)

The second prototype without canopy and powered by Continental A-65 engine.

Żak-3

Main production version with closed canopy and powered by Walter Mikron III engine, 10 built.

Żak-4 (SP-BAE)

Prototype of the glider towing version with open canopy (later refitted with a closed one) and powered by Walter engine.

Operators

 Poland

• Aeroklub Polski

Survivors

Żak-3 SP-AAX is preserved in the Polish Aviation Museum in Kraków (disassembled as for 2007)

Specifications (Żak-3)

Data from Jane's All The World's Aircraft 1953-54 [1]

General characteristics

• Crew: 2
• Length: 7.60 m (24 ft 11 in)
• Wingspan: 11.80 m (38 ft 9 in)
• Height: 1.95 m (6 ft 5 in)
• Wing area: 17.0 m² (183 sq ft)
• Empty weight: 400 kg (882 lb)
• Gross weight: 620 kg (1,367 lb)
• Powerplant: 1 × Walter Mikron III air-cooled 4-cylinder straight engine, 48 kW (65 hp)

Performance

• Maximum speed: 160 km/h (99 mph, 86 kn)
• Cruise speed: 130 km/h (81 mph, 70 kn)
• Stall speed: 62 km/h (39 mph, 33 kn)
• Range: 400 km (250 mi, 220 nmi)
• Service ceiling: 3,500 m (11,500 ft)
• Rate of climb: 2.7 m/s (530 ft/min)

See also

Aircraft of comparable role, configuration, and era

• Bücker Bü 181
• RWD-21
• Zlin Z-22 Junak

References

• Babiejczuk, Janusz and Grzegorzewski, Jerzy: Polski przemysł lotniczy 1945-1973 (Polish aviation industry...), Wydawnictwo MON, Warsaw 1974 (in Polish)
• Bridgman, Leonard. Jane's All The World's Aircraft 1953-54. London:Jane's,1953.
• Krzyżan, Marian: Samoloty w muzeach polskich, Warsaw 1983, ISBN 978-83-206-0432-0 (in Polish)
• Photo and description at Poser page (in Polish)

External links

Wikimedia Commons has media related to LWD Żak.

• Photos at Ugolok Neba page

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