Schempp-Hirth Ventus

The Schempp-Hirth Ventus is a sailplane produced during 1980–1994 by Schempp-Hirth, a German sailplane manufacturer.[1] It was designed by Klaus Holighaus and replaced the Schempp-Hirth Mini-Nimbus. Schempp-Hirth manufactured 613 Ventus sailplanes.

Ventus
Bielsko-Biała Air Show (2009), Schempp-Hirth Ventus 2cT
Role 15 metre-class sailplane
National origin Germany
Manufacturer Schempp-Hirth
Designer Klaus Holighaus
First flight 1980
Number built ca. 611
Variants Schempp-Hirth Ventus 2
External image
Schempp-Hirth Ventus approaching to land

Design and development

The decline in the cost of carbon fibre during the 1970s allowed sailplane designers to design large components from carbon-fibre reinforced plastic (CFRP). The use of carbon-fibre lay-ups, designed to reduce aero-elasticity of wings, has allowed CFRP gliders to be designed to cruise at much higher speeds than those with wings made from fibreglass (GFRP) or wood, as well as take advantage of thinner aerofoil sections. The Ventus has a 15-metre wingspan, using CFRP in its structure, complying with 15 m Racing Class specifications. Extended wingtips can be fitted to increase the span to 16.6 metres for competition in the Open Class. The fuselage was also produced in two sizes to suit pilots of different heights – the Ventus A for short pilots and Ventus B with a longer and wider cockpit. Both Ventus A and Ventus B have a complex flap/brake arrangement similar to that of the Glasflügel Mosquito and the Mini-Nimbus, but the Ventus C reverted to conventional upper-surface air-brakes that are separate from the trailing-edge flaps.

Wingtip extensions could be fitted to the Ventus A and B to increase the wingspan to 16.6 m. Longer extensions could be fitted to the Ventus C to increase the span to 17.6 m. Modified extensions with winglets are also available. Some Ventus Bs and Cs are equipped with a small sustaining engine ("turbo") and are designated with a T while some are equipped with a more powerful engine and are self-launching and are designated with an M.

The best measured glide ratio of a Ventus at 15 metres wingspan is 44:1, improving to 46:1 with the 16.6 metre tips, giving a creditable performance for the 1980s and 1990s. Ventus sailplanes won two World Gliding Championships, competing against the ASW 20 and later the LS6 in the 15 m class. Whilst the Ventus A and B acquired reputations for unparalleled high-speed glide performance, the Ventus C introduced improvements in handling.

About 613 Ventus sailplanes were built before being replaced by the Schempp-Hirth Ventus 2 in 1995.

The Ventus 1 remains a competitive glider winning national level competitions. The Ventus 1A is still being flown at the World Championship level in 2017.

Variants

data from:Schempp-Hirth Flugzeugbau GmbH website[2]

Ventus A (15m / 16.6m)
The production standard 15m class Ventus with shorter and narrower cockpit.
Ventus B (15m / 16.6m)
Production aircraft with larger cockpit for larger pilot.
Ventus BT (15m / 16.6m)
The Ventus B with a retractable sustainer motor.
Ventus C (15m / 17.6m)
Later model with improved handling and air brakes separate from the trailing-edge flaps.
Ventus CT (15m / 17.6m)
The Ventus C with a retractable sustainer motor.
Ventus CM (15m / 17.6m)
The Ventus C with a retractable motor for self-launching.

Specifications (Ventus c)

Data from Jane's All the World's Aircraft 1988–89[3]

General characteristics

  • Crew: 1
  • Length: 6.58 m (21 ft 7 in)
  • Wingspan: 17.6 m (57 ft 9 in) with extensions
  • Wing area: 10.15 m2 (109.3 sq ft) with extensions
  • Aspect ratio: 30.2 with extensions
  • Airfoil: Wortmann/Holighaus/Althaus section
  • Empty weight: 243 kg (536 lb)
  • Max takeoff weight: 430 kg (948 lb)
  • Water ballast: 160 l (42 US gal; 35 imp gal)

Performance

  • Stall speed: 58 km/h (36 mph, 31 kn)
  • Never exceed speed: 270 km/h (170 mph, 150 kn) in smooth air
200 km/h (110 kn; 120 mph) in rough air
180 km/h (97 kn; 110 mph) on aero-tow
150 km/h (81 kn; 93 mph) on winch launch
  • g limits: +5.3 -2.65
  • Maximum glide ratio: 49 at 100 km/h (54 kn; 62 mph) fuselage version "a"
  • Rate of sink: 0.54 m/s (106 ft/min) at 75 km/h (40 kn; 47 mph)
  • Wing loading: 33 kg/m2 (6.8 lb/sq ft)
abb/16.6bTccTcM
Wing span 15 m (49 ft) 15 m (49 ft) 15 m (49 ft) / 16.6 m (54 ft) 15 m (49 ft) / 16.6 m (54 ft) 15 m (49 ft) / 16.6 m (54 ft) / 17.6 m (58 ft) 15 m (49 ft) / 16.6 m (54 ft) / 17.6 m (58 ft) 15 m (49 ft) / 16.6 m (54 ft) / 17.6 m (58 ft)
Aspect ratio 23.7 23.7 23.7 / 27.7 23.7 / 27.7 23.7 / 27.7 / 30.2 23.7 / 27.7 / 30.2 23.7 / 27.7 / 30.2
Length 6.35 m (20.8 ft) 6.58 m (21.6 ft) 6.58 m (21.6 ft) 6.58 m (21.6 ft) 6.58 m (21.6 ft) 6.58 m (21.6 ft) 6.58 m (21.6 ft)
Wing area 9.51 m2 (102.4 sq ft) 9.51 m2 (102.4 sq ft) 9.51 m2 (102.4 sq ft) / 9.96 m2 (107.2 sq ft) 9.51 m2 (102.4 sq ft) / 9.96 m2 (107.2 sq ft) 9.51 m2 (102.4 sq ft) / 9.96 m2 (107.2 sq ft) / 10.15 m2 (109.3 sq ft) 9.51 m2 (102.4 sq ft) / 9.96 m2 (107.2 sq ft) / 10.15 m2 (109.3 sq ft) 9.51 m2 (102.4 sq ft) / 9.96 m2 (107.2 sq ft) / 10.15 m2 (109.3 sq ft)
Weight empty 240 kg (530 lb) approx. 240 kg (530 lb) approx. 243 kg (536 lb) approx. 240 kg (530 lb) approx. / 243 kg (536 lb) with sustainer removed 240 kg (530 lb) approx. / 243 kg (536 lb) 289 kg (637 lb) 300 kg (660 lb)
Max T/O weight 525 kg (1,157 lb) 525 kg (1,157 lb) 430 kg (950 lb) 525 kg (1,157 lb) / 500 kg (1,100 lb) with sustainer removed 525 kg (1,157 lb) / 500 kg (1,100 lb) 430 kg (950 lb) 430 kg (950 lb)
Max wing loading 55.2 kg/m2 (11.3 lb/sq ft) 55.2 kg/m2 (11.3 lb/sq ft) 43.2 kg/m2 (8.8 lb/sq ft) 55.2 kg/m2 (11.3 lb/sq ft) / 49.3 kg/m2 (10.1 lb/sq ft) with sustainer removed 55.2 kg/m2 (11.3 lb/sq ft) / 49.3 kg/m2 (10.1 lb/sq ft) 42.4 kg/m2 (8.7 lb/sq ft) 49.3 kg/m2 (10.1 lb/sq ft)
Max Power loading - - - - - 28.1 kg/kW (46.24 lb/hp) 9.62 kg/kW (15.8 lb/hp)
Best glide at 35 kg/m2 (7.2 lb/sq ft) 43.5 at 105 km/h (57 kn; 65 mph) 43.5 at 105 km/h (57 kn; 65 mph) 46.5 at 95 km/h (51 kn; 59 mph) - 43 / 49 at 105 km/h (57 kn; 65 mph) - 48–49 at 105 km/h (57 kn; 65 mph)
Min sink at 75 km/h (40 kn; 47 mph) 0.58 m/s (114 ft/min) 0.58 m/s (114 ft/min) 0.59 m/s (116 ft/min) - - - 0.62 m/s (122 ft/min) engine retracted
Stalling speed 65 km/h (35 kn; 40 mph) 65 km/h (35 kn; 40 mph) 64 km/h (35 kn; 40 mph) - - - 75 km/h (40 kn; 47 mph) (minimum speed)
Vne 250 km/h (130 kn; 160 mph) 250 km/h (130 kn; 160 mph) 250 km/h (130 kn; 160 mph) - 270 km/h (150 kn; 170 mph) - -180 km/h (97 kn; 110 mph) power on / 270 km/h (150 kn; 170 mph) engine retracted
Cruise - - - 130 km/h (70 kn; 81 mph) - - 140 km/h (76 kn; 87 mph)
Climb rate - - - 0.633–1.133 m/s (124.6–223.0 ft/min) - - 2 m/s (390 ft/min)
Take-off run - - - - - - 280 m (920 ft) / 420 m (1,380 ft) to 15 m (49 ft)
Range - - - 201 km (109 nmi; 125 mi) + (sawtooth) - - 500 km (270 nmi; 310 mi) (sawtooth) / 320 km (170 nmi; 200 mi) (level)
Endurance - - - - - - 2 hours

See also

Related lists

Notes
  1. "SCHEMPP-HIRTH FLUGZEUGBAU GmbH". sailplanedirectory.com. Retrieved 22 January 2015.
  2. "Ventus". schempp-hirth.com. Archived from the original on 22 January 2015. Retrieved 22 January 2015.
  3. John W.R. Taylor, ed. (1988). Jane's All the World's Aircraft 1988–89. London: Jane's Information Group. pp. 630–632. ISBN 0-7106-0867-5.

Further reading
  • Milgram, Fred Thomas; Judah; translator; contributor (1999). Fundamentals of sailplane design (3rd ed.). College Park, MD: College Park Press. ISBN 978-0966955309.
  • Simons, Martin (2005). Sailplanes 1965–2000 (2nd revised ed.). Königswinter: EQIP Werbung und Verlag G.m.b.H. ISBN 978-3-9808838-1-8.
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