PZL Bielsko SZD-8

SZD-8 Jaskółka
SZD-8bis in the Brussels Army Museum
Type:	High performance glider
Design country:	Poland
Manufacturer:	PZL Bielsko
First flight:	September 21, 1951
Commissioning:	1952
Production time:	1952-1958
Number of pieces:	135

The PZL Bielsko SZD-8 Jaskółka ( German  Swallow ) is a Polish high-performance glider of the open class . The abbreviation SZD stands for the Bielsko-Biała- based manufacturer Szybowcowy Zakład Doświadczalny (glider development plant).

development

The SZD-8 was one of the first Polish high-performance gliders. The construction work was carried out under the direction of Tadeusz Kostia. The first prototype was completed in 1951 and, with the registration number SP-1222 , made its maiden flight with Adam Zientka on September 21. It was difficult to get out of the flat spin and was therefore revised. The fuselage was lengthened by around 70 cm and the tail unit area increased. The following tests were flown by Adam Dziurzynski, who carried out about 1000 spin tests with the prototype. In the meantime a second prototype had been built and flown on December 3, 1951 as the SZD-8-2 and the registration number SP-1223 . The further tests dragged on for a few months, but finally production started in 1952. Following the findings from the trials, the series models were given a slightly different hull line, a modified design of the main spar in the front area and different aileron mechanisms. They were also equipped with air brakes and some of them received retractable main landing gear wheels. On December 24, 1952, Adam Zientka again completed the maiden flight with the first production model ( SP – 1305 ), which was given the designation SZD-8bis and was built 30 times.

In the years that followed, a number of variants were created in which the shape of the bow section in particular was often designed differently. Among other things, Stanisław Wielgus developed the SZD-8bis III and SZD-8bis 0, tailored for export, with minor improvements. The highlight was the SZD-8ter Z, flown for the first time on May 2, 1958, and the SZD-8ter ZO with a modified fuselage-wing transition made of laminate and air brakes made of metal, 40 of which were made. With the latter, 15 world records could be flown between May 1954 and May 1960. Jaskółkas also took top places in the world gliding championships, with Marian Gorzelak in 3rd place in Saint-Yan in 1956 and Edward Makula in 5th place in 1958 in Leszno .

By the end of production in 1958, 135 SZD-8s of all versions had been built. 75 pieces were exported to 14 countries, 15 of them SZD-8bis from 1955 to 1957 to the GDR , where they were used by the GST . The last of these Jaskółkas was deleted from the register in 1973. China also received the model and developed it further into the X-10, which was built in Shenyang in large numbers from 1958 .

Other models and successors to the Jaskółka series were the SZD-14 Jaskółka M and the SZD-17 Jaskółka L , both with a V-tail . The fuselage of the SZD-8 formed the basis for the SZD-11 Albatros . As a high-performance sailor, the Jaskółka was replaced by the SZD-19 Zefir and the SZD-24 Foka .

Versions

• SZD-8 Jaskółka : first prototype
• SZD-8-2 Jaskółka : second, improved prototype
• SZD-8bis Jaskółka bis : first series from 1952, 30 pieces were built
• SZD-8bis E Jaskółka E : second series from 1954, 30 (49?) Pieces were built
• SZD-8bis W Jaskółka W : Execution of the experiment with a water ballast container that could be deflated in 2.5 minutes in flight. Only one copy was built in 1954
• SZD-8bis Z Jaskółka Z : Series version with modified body line, modified rudder linkage , different instrument panel and adjustable rudder pedal. 28 units were built in 1954/1955
• SZD-8bis III : Export version based on the SZD-8bis E and Z with spring-loaded main wheel, metal tail skid and ball bearing rudder joints. There was probably no series production
• SZD-8bis 0 Jaskółka 0 : Export version based on the SZD-8bis Z with modified instrument panel and KP-14 oxygen system. In 1955/1956 five were built
• SZD-8ter Z Jaskółka Z : Version with metal air brakes, laminate fuselage-wing transition, water ballast container and a new instrument panel. In 1958 ten copies were made
• SZD-8th ZO Jaskółka ZO : like SZD-8th Z, but without water ballast. 30 units were built in 1957/1958. Most powerful Jaskółka version, with which several records were flown

construction

The SZD-8 is a cantilevered middle decker made of wood. The fuselage, with an oval cross-section that tapers towards the rear, consists of a framework covered with plywood. The wings are single-spar and also plywood-clad. They are equipped with air brakes that extend up and down and are coupled to the main wheel, if it is designed to be retractable. The undercarriage consists of the rigid or retractable 300 × 130 mm main wheel, a front runner with different lengths, depending on the version, and a rear runner made of wood or metal. All oars consist of a wooden frame with a fabric covering.

Technical specifications

Parameter	SZD-8 Jaskółka	SZD-8bis Jaskółka bis	SZD-8bis Jaskółka E	SZD-8bis Jaskółka W	SZD-8th Jaskółka ZO
span	16.0 m
length	6.74 m	7.42 m
height	1.28 m	1.41 m	1.9 m	1.41 m
Wing area	13.6 m
Wing extension	18.8
Empty mass	275.5 kg	252 kg		267.5 kg	270 kg
Water ballast	No			95 kg	95 kg (only Jaskółka Z)
maximum take-off mass	365.5 kg	342 kg		357.5 kg	360 kg
maximum wing loading	26.8 kg / m²	25.2 kg / m²		26.4 kg / m²	26.5 kg / m²
Top speed	250 km / h
Minimum speed	50 km / h	55 km / h
Glide ratio	25.4 at 80 km / h	26.4 at 80 km / h			28.5 at 83 km / h
Slightest sinking	0.76 m / s at 65 km / h	0.76 m / s at 68 km / h		0.78 m / s at 70 km / h	0.75 m / s at 74 km / h
crew	1

SZD-8 in Germany

SZD-8bis at the Leipzig autumn fair in 1954. The SP-1596 was the first Jaskółka to be delivered to the GDR the following year

Below is a list of the SZD-8bis used in the GDR. Unless otherwise stated, it was used by GST.

Work number	Mark	Commissioning	Decommissioning	Remarks
150	(exDDR–) DM – 2014	April 07, 1955	2nd November 1970	exSP-1596
130	(exDDR–) DM – 2017	May 6, 1955	May 23, 1969	exSP-1534
123	(exDDR–) DM – 2018	1955	15th February 1971	exSP-1527
122	(exDDR–) DM – 2019	May 6, 1955	5th September 1972	exSP-1526
120	(exDDR–) DM – 2020	May 29, 1955	September 30, 1966	exSP-1524
140	(exDDR–) DM – 2021	1955	20th August 1971	exSP-1544
158	(exDDR–) DM – 2022	August 19, 1955	June 1965	exSP – 1604 deleted after severe damage
159	(exDDR–) DM – 2023	August 19, 1955	18th January 1968
160	(exDDR-) DM-2024	August 19, 1955	March 9, 1971
175	(exDDR-) DM-2026	May 5th 1956	September 25, 1967	Use at ASV
174	(exDDR-) DM-2027	1956	January 26, 1973
161	(exDDR-) DM-2028	March 22, 1956	2nd November 1970
162	(exDDR-) DM-2029	April 12, 1956	May 27, 1963
167	(exDDR-) DM-2030	April 22, 1956	May 14, 1971
169	(exDDR-) DM-2031	June 22, 1957	February 23, 1970

literature

• Kazimierz Wojciech Chudzinski: Polish gliders . Volume 1: 1945-1970. Verlag für Technik und Handwerk, Baden-Baden 2014, ISBN 978-3-88180-454-7 .
• SZD Jaskolka (VR Poland) . In: Central Board of GST (ed.): Fliegerrevue . No. 1/89 (431) . Military Publishing House of the GDR , Berlin 1988, p. 30 .

Web links

Commons : SZD-8 Jaskółka  - collection of pictures, videos and audio files

Remarks

1. ↑ Other data speak of up to 155 SZD-8s built (see Chudzinski, p. 284). This difference can mainly be explained by the different production figures of the second series from 1954, which are indicated with either 30 or 49 built SZD-8bis E.

Individual evidence

1. ^ ^{A b} Detlef Billig, Manfred Meyer: Airplanes of the GDR . III. Volume until 1990. 1st edition. TOM Modellbau, Friedland 2003, ISBN 3-613-02285-0 , p. 162 .
2. ↑ Glider construction . In: Central Board of GST (ed.): Fliegerrevue . No. 7/81 (341) . Military Publishing House of the GDR, Berlin 1981, p. 295 .