Jilles Smits SZD-8 Jaskółka

SZD-8 Jaskółka

The SZD-8 Jaskółka was a single-seat glider aircraft that was designed and built-in Poland at Szybowcowy Zakład Doświadczalny (Glider Experimental Works) in Bielsko-Biała from 1951.

Jaskółka (Swallow)Development

With prototypes rolled out in September and December 1951, the SZD-8 Jaskółka (Swallow) was a high-performance glider for its day, introducing several innovations to glider design such as a sliding moulded Plexiglas canopy, recessed handle in the rear fuselage for ground handling and a semi-retractable main wheel. The all-wood wings were covered with plywood and fabric incorporating Fowler flaps on the trailing edges, which could be lowered to 12° or 25°, and Schempp-Hirth style air brakes aft of the main spars. The main designer was Tadeusz Kostia. The first prototype was flown on 21 September 1951 (test pilot Adam Zientek), but it revealed faults. After reconstruction, with longer fuselage and enlarged rudder (designated SZD-8-2), it appeared successful and was ordered into production, becoming the most popular competition glider in Poland from 1953 to 1957. Many of the 135 production aircraft were exported, garnering at least fifteen world records from May 1954 to May 1960. Licensed production was also carried out in the DDR (Deutsche Demokratische Republik – German Democratic Republic) and the PRC (People’s Republic of China). Several variants were produced which introduced various improvements and modifications.

Variants

SZD-8
two prototypes, first flown 21 September 1951
SZD 8-2
first prototype after reconstruction, first flown 16 March 1952
SZD-8bis Jaskółka
initial production variant (first flown 24 December 1952; 30 built)
SZD-8bisE Jaskółka E
improved variant of 1954 (30 built)
variant with water ballast (1 built, later converted to SZD-8bisZ)
SZD-8bisZ Jaskółka Z
one prototype
SZD-8bisO Jaskółka O
export variant
SZD 8terZ Jaskółka Z
variant with water ballast, introduced in May 1958
SZD 8terZO Jaskółka ZO
variant without water ballast, introduced in 1958
a licensed version of the SZD-8/14 Jaskółka, with modifications, built in the People’s Republic of China at the Shenyang aviation factory.

Specifications (SZD-8bis Jaskółka Z)

General characteristics

Crew: 1
Length: 7.42 m (24 ft 4 in)
Wingspan: 16 m (52 ft 6 in)
Height: 1.41 m (4 ft 8 in)
Wing area: 13.6 m2 (146 sq ft)
Aspect ratio: 15
Airfoil: NACA 43 012A
Empty weight: 270 kg (595 lb) equipped
Gross weight: 337 kg (743 lb)
Max takeoff weight: 455 kg (1,003 lb)

Performance

Never exceed speed: 250 km/h (160 mph, 130 kn)
Aerotow speed: 150 km/h (81.0 kn; 93.2 mph)
Winch launch speed: 120 km/h (64.8 kn; 74.6 mph)
g limits: +3.5 -1.75 at 250 km/h (135.0 kn; 155.3 mph)
Maximum glide ratio: 28.5 at 82 km/h (44.3 kn; 51.0 mph)
Rate of sink: 0.75 m/s (148 ft/min) at 75 km/h (40.5 kn; 46.6 mph)
Wing loading: 7.34 kg/m2 (1.50 lb/sq ft)