Schempp-Hirth Ventus

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Schempp-Hirth Ventus
A Ventus in the winch launch
Type: Glider the m- 15-and 18-m class
Design country:

Germany Federal RepublicFederal Republic of Germany BR Germany

Manufacturer:

Schempp-Hirth

First flight:

1980

Production time:

1980 to today (Ventus 3)

The Schempp-Hirth Ventus (from Latin ventus for wind ) is a single-seat high-performance glider with parts made of carbon fiber reinforced plastic . It was designed by Schempp-Hirth in Kirchheim (Teck) in 1980 for the 15 m class and brought onto the market as the successor to the Mini-Nimbus .

history

Ventus 3 at Lasham Airfield, England

The achievements of the "FAI racing class " at the time such as B. Glass wing Mosquito or Schempp-Hirth Mini-Nimbus , Eiri Avion Pik 20 , roller shutter Schneider LS3 , Grob Speed-Astir , were specially designed with the introduction of the roller shutter Schneider LS4 in spite of their unchangeable wing profile z. In some cases it was exceeded, which made it urgently necessary to rethink the constructions for the racing class and the necessary flap profiles. Overall, at that time the discussion was already going to replace the 15 m class with a somewhat larger 17–18 m class, to which the excellent design of the Kestrel glass wing contributed a lot. Thus, in the "racing class", the introduction of attachable wing tips for pure performance flights became common. But it wasn't until 2001 that the 18-meter class was officially introduced.

Versions

Ventus A and B

The fuselage of the Ventus was available in two versions: the narrow Ventus-A and the Ventus-B for larger pilots. Several world championships were won with this aircraft in the 1980s. The span could be increased from 15 m to 16.6 m by attaching surfaces. As with the predecessor, rear-edge rotary brake flaps were used.

Ventus C

Ventus C with patch surfaces

The Ventus C is a stand-alone version , which has a new, spacious fuselage that is almost identical to the Discus CS and whose wingspan can be increased from 15 m to 17.6 m for performance flights by means of clip-on wings. There are again motorized versions with homecoming aid (Ventus cT) or as a self-starter (Ventus cM) .

From an aerodynamic point of view, the wing is swept slightly forward, only the clip-on wings of the 17.6 m version are swept back slightly. For use in the 15 m racing class, there are various wing tips with winglets of different sizes, but there are also simple edge caps. The 17.6 m version has small spring-loaded flaps on the attachment surfaces, which are automatically taken upwards by the continuous flaperons , but remain in the neutral position when they are deflected downwards. This system was also adopted for the later Duo-Discus. In contrast to its predecessors, the Ventus C has normal Schempp-Hirth brake flaps.

The flaperons can be locked in positions −2, −1, 0, +1, +2 and L (landing position), whereby the contouring of the torso corresponds to position −1. Only the two negative positions are permitted in high-speed flight from 140 km / h. The response of the flaperons in flight is harmonious and far better than that of the related Discus CS with rigid profile. The extremely low control pressure is also noticeable.

However, when landing, the flaperons must be brought to the zero position or a negative position as quickly as possible after they have touched down safely, as the aileron effect decreases disproportionately with the positive flap positions when the speed on the ground decreases. For this reason, positive flap positions are not recommended in the roll-up phase at the start. Although this increases the pilot's workload during take-off and landing compared to other models, it is due to the design with the continuous flaperons. Rolladen Schneider therefore abandoned the concept of continuous flaperons for the LS3a and again used separate rudder flaps.

Ventus 2

The successor Ventus-2 is also available with a narrow (-2a) and a wider body (-2b).

Ventus 2

Similar to the original Ventus, the majority of the built specimens are B-versions, since the A-fuselage is already extremely narrow for normally built Central Europeans and is therefore only of interest to competition pilots who consciously accept the lack of comfort due to its lower air resistance .

Characteristic of the Ventus-2 is the wing with the multiple swept leading edge known from the Discus . A number of victories at European and World Championships were also flown with the Ventus-2.

The Ventus-2cx model got a new outer wing and a tail unit that was also adapted for the 18 m class. Furthermore, the maximum take-off weight has been increased to up to 600 kg. All Ventus-2c models are available with a 15 m or 18 m span as well as with a homecoming aid or as a self-starter with an 18 m span.

The gliding index of the different versions ranges from 110 to 119.

Ventus 3

The Ventus 3 is a new design that takes into account the latest findings in sailplane construction. In the "Sport Edition", installation and retrofitting options for a homecoming aid are provided as standard. In addition, there is a “Performance Edition” analogous to the previous Ventus and Ventus 2 models. The wing swept back in several segments with large winglets is striking.

Technical specifications

Ventus a
Ventus b
Ventus bT
Ventus c
Ventus cT
Ventus cM Ventus 2a
Ventus 2ax
Ventus 2b
Ventus 2bx
Ventus 2bxR
Ventus 2c
Ventus 2cT
Ventus 2cx
Ventus 2cxa
Ventus 2cxT
Ventus 2cxR
Ventus 2cM
Ventus 2cxM
Ventus 3
Ventus 3T
span 15 m 17.6 m 15 m 18 m
Wing area 9.51 m² 10.15 m² 9.67 m² 11.03 m² 10.84 m²
Wing extension 23.7 30.2 23.3 29.5 29.9
Hull length 6.58 m 6.35 m 6.81 m 6.76 m
Empty mass ~ 250 kg ~ 253 kg ~ 310 kg ~ 240 kg ~ 310 kg ~ 380 kg (2cM)

~ 400 kg (2cxM)

~ 300 kg 360 kg
Max. Takeoff mass 525 kg 500 kg 430 kg 525 kg 525 kg / 600 kg (x variants) 600 kg
Wing loading 31.5-55.2 kg / m² 31.5-49.3 kg / m² 37.9-42.3 kg / m² 30.5-54.3 kg / m² 30.5-47.7 kg / m²

30.5-54.4 kg / m² (x variants)

43-47.7 kg / m² (2cM)

45–54.4 kg / m² (2cxM)

34-55 kg / m² 38-55 kg / m²
Water ballast 168 l - 200 l 180 l
Top speed 250 km / h 270 km / h 285 km / h 280 km / h ?
Maneuver speed 200 km / h 180 km / h 200 km / h
Slightest sinking 0.58 m / s 0.51 m / s 0.55 m / s
Glide ratio ~ 43 ~ 48 ~ 46 ~ 50 ? ?
Engine - SOLO 2350 C; 20.0 kW

(27.2 HP)

- SOLO 2350; 15.3 kW

(20.5 HP)

SOLO 2625; 38 kW

(51 HP)

SOLO 2350; 15.3 kW

(20.5 HP)

See also

Web links

Commons : Schempp-Hirth Ventus  - collection of images, videos and audio files

Individual evidence

  1. ^ [Flight manual Ventus cM, March 1989]