Allstar SZD-59

SZD 59 Acro
Role	Club Class and aerobatic glider
National origin	Poland
Manufacturer	Allstar PZL Glider Sp.z o.o.
Designer	Jan Knapik[1]
First flight	9 September 1991[1]
Number built	2 prototypes and 23 or more serial ones[1]
Developed from	PZL Bielsko SZD-48-3 Jantar 3

The SZD-59 Acro is a single-seat glass composite glider for aerobatics and cross-country flying by PZL Allstar of Bielsko-Biała, Poland.^[2][3][4]

The SZD-59 can be flown with a 13.2m span or a 15.0m span. Attaching or detaching the wing-tips takes only a few minutes.^[1][3] With 15m wing-tips it is a competitive Club Class glider, while it is a competitive aerobatic glider in the 13.2m configuration.^[4]

Design and certification

The SZD-59 Acro was derived from the SZD-48-3 Jantar Standard 3^[2] in 1990–91 mainly by Jan Knapik.^[1][4] The fuselage is only a slightly modified version of the one used in the Jantar Standard 3. However, the T-tail has been replaced by a cross-tail with larger rudder and the elevator of the SZD-42-2 Jantar 2.^[4]

The design life is 15,000 hours, though at present it is approved for only 4,000 hours of operation.^[2][3] In 15m configuration, the SZD-59 is approved in the utility category of JAR 22 (sailplanes) of the Joint Aviation Authorities, and in the 13.2m configuration it is approved according to the aerobatics category of JAR 22.^[1][5]

Manufacturer

The prototype was first demonstrated during the 1991 FAI World Glider Aerobatic Championships in Zielona Góra. Twelve Acros were built by PZL-Bielsko until the production stopped in 1996 due to economic problems.^[4] Allstar PZL Glider Sp. z o.o. in Bielsko-Biała (Poland)^[3] restarted production of the SZD-59 Acros in 2004.^[4] Currently, it is the only unlimited glider in serial production.^[4]

Soaring

With a handicap factor of 100, according to the 2008 handicap list of the Deutscher Aero Club e.V.,^[6] the SZD-59 in 15m-configuration is a typical Club Class glider. With 15m wing-tips with or without winglets glide performance can be enhanced by increasing its wing loading with up to 150 litres of water ballast,^[3] but water ballast is not allowed in the 13.2m configuration.^[7]

Aerobatics

In the 13.2m configuration, the SZD-59 is certified for unlimited aerobatics,^[3] whereas with the 15m wing-tips only basic aerobatic maneuvers (looping, turn, chandelle, spin) are permitted.^[7]

While international aerobatic championships in the unlimited category are dominated by Swift S-1 and MDM-1 Fox,^[8] pilots have competed successfully with SZD-59 Acros in national and regional championships.^[4] Recently, Wolfgang Kasper placed 4th in the German Nationals 2008.^[9]

Specifications in utility configuration

Data from ,^[3] maximum and maneuver speed according to ^[5]

General characteristics

• Crew: One
• Length: 6.85 m (22 ft 5.69 in)
• Wingspan: 15.00 m (49 ft 2.55 in)
• Height: 1.50 m (4 ft 11.06 in)
• Wing area: 10.66 m² (114.74 sq ft)
• Aspect ratio: 21.01
• Empty weight: 270 kg (595.24 lb)
• Gross weight: 540 kg (1,190.48 lb)

Performance

• Maximum speed: 265 km/h (164.67 mph, 143.09 kn)
• Stall speed: 82 km/h (50.95 mph, 44.27 kn) ^*
• g limits: +5.3 / -2.65^[10]
• Maximum glide ratio: 40 at 124 km/h^*
• Rate of sink: 0.77 m/s (151.57 ft/min) ^**
• Maneuver speed: 200 km/h
• Water ballast: 150l
• Wing loading range: 31.00-50.70 kg/m²

^* at 540 kg
^** at 97 km/h

Specifications in aerobatic configuration

SZD 59 Acro (prototype in 13.2m configuration)

Data from ,^[3] maximum and maneuver speed according to ^[5]

General characteristics

• Crew: One
• Length: 6.85 m (22 ft 5.69 in)
• Wingspan: 13.20 m (43 ft 3.69 in)
• Height: 1.50 m (4 ft 11.06 in)
• Wing area: 9.80 m² (105.49 sq ft)
• Aspect ratio: 17.80
• Empty weight: 265 kg (585.22 lb)
• Gross weight: 380 kg (837.75 lb)

Performance

• Maximum speed: 285 km/h (177.10 mph, 153.90 kn)
• Stall speed: 74 km/h (45.98 mph, 39.96 kn) ^*
• g limits: +7.00 / -5.00
• Maximum glide ratio: 36 at 115 km/h
• Rate of sink: 0.70 m/s (137.80 ft/min) ^**
• Maneuver speed: 200 km/h
• Water ballast: 0l
• Wing loading range: 33.7-38.8 kg/m^2[11]

^* at 380 kg
^** at 80 km/h

See also

Comparable aerobatic gliders

The aerobatic performance of the SZD-59 13.2m is comparable to:

• Celair GA-1 Celstar
• MDM-1 Fox and Solo-Fox
• Swift S-1
• Cirrus K
• Start & Flug H101 Salto
• Vogt Lo-100

Gliders with comparable cross-country performance

The soaring performance of the SZD-59 15m is comparable to Schleicher ASW 19, Glaser-Dirks DG-100, Rolladen-Schneider LS1f, Glasflügel H206 Hornet, PZL Bialsko Jantar Standard, Grob G102 Standard Astir, Bölkow Phöbus B3, Schempp-Hirth Cirrus/Cirrus VTC 17,74m, Schempp-Hirth Standard Cirrus 16m, Bölkow Phöbus C1, Akaflieg Darmstadt D37, Akaflieg Braunschweig SB 7, Neukom Elfe 17m, Standard Libelle 17m and the Delphin 1 by Fritz Mahrer.^[6][12]

References

1. Piotr Piechowski: SZD-59 Acro (German) – accessed 2008-02-23
2. Official SZD-59 Acro website – accessed 2008-02-23
3. Technical description of the SZD-59 Acro on SZD's website – accessed 2008-02-23; unavailable 2008-08-06, but equivalent to: Technical description of the SZD-59 Acro on the website of the German dealer (in German)^{[permanent dead link‍]} – accessed 2008-08-06
4. SAGA: SZD-59 Acro website (in German) – accessed 2008-02-23
5. British Gliding Association: Segelflugzeug-Kennblatt Nr.: 415 (German) by the Luftfahrt-Bundesamt – accessed 2008-08-05
6. 2008 DAeC Handicap list – accessed 2008-02-23
7. Flight handbook of the SZD-59 Acro
8. FAI World and European Glider Aerobatic Championships – accessed 2008-08-05
9. Results of the German Glider Aerobatic Championships 2008 (unlimited)^{[permanent dead link‍]} – accessed 2008-08-02
10. Allstar PZL Glider Sp website ^{[dead link‍]}
11. calculated from data in Datasheet of the SZD-59 Acro on the SZD-Website – accessed 2008-02-23 – assuming a pilot weight of 55kg and 10kg trim weight
12. Das Projekt "Delphin 1" (German) – accessed 2008-08-05