avia.wikisort.org - Glider

The SZD-14X Jaskółka M was a single-seat glider designed and built in Poland at Szybowcowy Zakład Doświadczalny - Glider Experimental Works in Bielsko-Biała in 1954. This was an experimental prototype, and only one unit was constructed.[1]

SZD-14x Jaskółka M
Role	Glider aircraft Type of aircraft
National origin	Poland
Manufacturer	SZD Władysław Okarmus
Designer	Tadeusz Kostia
First flight	23 July 1954
Number built	1
Developed from	SZD-8 Jaskółka

Development

The SZD-14X Jaskółka M was developed from the SZD-8bis Jaskółka (Swallow) for research into the construction, control and characteristics of 'V' or butterfly tail surfaces.[2] Using the airframe of the second prototype SZD-8 a 'V' tail was added to the rear fuselage, with arrangements for the balance of the surfaces and the angle between them to be adjusted as required.[1] The designer was Tadeusz Kostia, the constructor was Władysław Okarmus.[3]

First flown by Adam Zientek at Bielsko on 23 July 1954,[3] the SZD-14 was found to be easy to fly with no vices, giving no indication that the tail layout was unconventional.[1] During spinning tests the rear fuselage was almost torn off, but the pilot (Dziurzyński) managed to regain control and recovered the aircraft to land safely.[2]

Up to the time of the SZD-14's debut, the 'V' tail system was rare, with few aircraft using the system devised by Eng. Jerzy Rudlicki and demonstrated on a licence-built Hanriot HD.14 biplane in the early 1930s.[4]

Specifications (SZD-14x Jaskółka M)

Data from http://www.piotrp.de/SZYBOWCE/pszd14.htm

General characteristics

• Crew: 1
• Length: 6.48 m (21 ft 3 in)
• Wingspan: 16 m (52 ft 6 in)
• Height: 1.3 m (4 ft 3 in)
• Wing area: 13.6 m² (146 sq ft)
• Aspect ratio: 18.8
• Airfoil: NACA 23012A
• Empty weight: 288 kg (635 lb)
• Gross weight: 373 kg (822 lb)

Performance

• Maximum speed: 250 km/h (155 mph, 135 kn)
• Stall speed: 59 km/h (37 mph, 32 kn)
• Maximum glide ratio: 26.3 at 80 km/h (43 kts/50 mph)
• Rate of sink: 0.70 m/s (138 ft/min) at 69 km/h (43 mph/37 kts)

See also

Related development

• SZD-8 Jaskółka
• SZD-17X Jaskółka L

Aircraft of comparable role, configuration, and era

• Standard Austria

References

• Taylor, J. H. (ed) (1989) Jane's Encyclopedia of Aviation. Studio Editions: London. p. 29
• Cynk, Jerzy B.. “Polish Aircraft 1893–1939”. London, Putnam. 1971. ISBN 0-370-00085-4
• Simons, Martin. Sailplanes 1945-1965 2nd revised edition. EQIP Werbung und Verlag G.m.b.H.. Königswinter. 2006. ISBN 3-9807977-4-0
• (in Polish) Babiejczuk, Janusz and Grzegorzewski, Jerzy. Polski przemysł lotniczy 1945-1973 [Polish aerospace industry 1945-1973]. Warsaw: Wydawnictwo MON, 1974

External links

• http://www.piotrp.de/SZYBOWCE/pszd14.htm

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