Engineering:Letov Š-39

Š-39
Letov Š-239
Role	Sport aircraft
National origin	Czechoslovakia
Manufacturer	Letov
First flight	1931

The Letov Š-39 was a sport aircraft produced in Czechoslovakia during the 1930s. It was a conventional, parasol-wing monoplane with fixed tailskid undercarriage, and seating for the pilot and passenger in tandem, open cockpits. Because the cabane struts were very short, and the wing therefore placed very close to the top of the fuselage, the cockpits had the unusual arrangement of the passenger's being in front of the wing while the pilot's was behind it. The outer half of each wing was fitted with fixed slats along the leading edge. An initial batch of 23 machines was built for use by Czech aeroclubs. These were followed by batches of aircraft with alternative powerplants.

Variants

Letov Š-39 (OK-WAN) with Walter Polaris II engine

Š-39

Prototype with Orion LL-50 engine followed by production batch with Walter Polaris engines

Š-139

Production model with Pobjoy R engine and Townend ring

Š-239

Production model with Walter Minor 4 engine

Specifications (Š-39)

Three-view drawing, Letov Š-239

General characteristics

• Crew: One pilot
• Capacity: 1 passenger
• Length: 6.14 m (20 ft 2 in)
• Wingspan: 10.00 m (32 ft 10 in)
• Wing area: 14.0 m² (151 sq ft)
• Empty weight: 315 kg (693 lb)
• Gross weight: 515 kg (1,133 lb)
• Powerplant: 1 × Walter Polaris , 41 kW (55 hp)

Performance

• Maximum speed: 150 km/h (94 mph, 82 kn)
• Range: 480 km (300 mi, 260 nmi)
• Service ceiling: 3,300 m (10,800 ft)
• Rate of climb: 2.1 m/s (410 ft/min)

References

• Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. pp. 573. 
• Němeček, Václav (1968). Československá letadla. Prague: Naše Vojsko.