Windtech Tempest SSS
(Translated by Carlo Borsattino)
The long awaited Quarx 2 replacement comes with more performance, and exceptional handling and speed capabilities.
It has inherited the floating double-layer reinforcements in the secondary cell-ribs of the leading edge which were developed for the Tactic, but without it's trapezoidal half-closed cell openings.
In reality, everything is new: profile, planform and cell structure, with the aerodynamic tension tuned for flying fast. The line layout is simplified to two levels to reduce parasitic drag.
It has open cells of variable width and a very solid leading edge. It's handling is very agile, easy to get to grips with and control with just a touch of brake (it has little tendency to surge forwards).
It thermals with the greatest of ease and the turn can be nicely flattened with a little outside brake. The speed system offers a net gain which is both substantial and usable without any drawbacks whatsoever up to half-bar, and you can push it all the way to full-bar without the leading edge creasing or fluttering.
Excellent speed, glide and handling are common qualities (according to their respective category) of all the current Windtech models: Tempus, Pulsar, Kinetik, Tempest, Tactic and Bantoo.
4 years with the Quarx (1 and 2), and it was time for a renewal. This time there has not been just small adjustments in the trim and line layout, they have made a completely new wing. Its planform, aspect ratio and the complexity of the leading edge suggest more of a high performance model than an intermediate.
A very simplified 2-stage line layout (in favour of increased performance), fully-opened cells and a rigid leading edge thanks to the 'S3' system of double layered inter-cell reinforcements. The front part of each rib is highly reinforced with stiff Dacron. The whole new wing profile has a level of definition which is quite remarkable, featuring a considerably rounded leading edge and the somewhat forward position of it's maximum depth.
|S.S.S. (Security Speed System): A system of floating reinforcements in the inter-cell ribs, with doubled-over material. They give rigidity to the leading edge, eliminate creases and improve the behaviour and performance of the wing in accelerated flight. On the downside, more load in inflation and a degree of complexity in manufacture.
The wingtips keep with the classic Windtech design (which gives a distinctiveness to all of their models, together with the tricolour-arrow pattern of the inverted 'W' motif).
To improve internal pressure, it has diagonal and transversal trapezoidal ribs, internal load-bearing cross-webbing straps to link up the line cascades, and a leading edge which is equipped with sufficient stiffening-reinforcements of the principal and secondary ribs, as well as the borders of the cell openings.
The trailing edge is protected with a stitched Mylar strip, and the brake lines are attached one and a half cell-widths apart.
The risers have an extensive speed-bar travel (which is light), with a double pulley system, and the A's are split - not just for pulling big-ears, but also so that the wing tips have a less-reduced angle of attack, compared to the centre when accelerated, making it more stable.
Turn as you wish
Take-off is easy, the cell-openings remain pre-inflated at all times because of the reinforcements and you just need to consider the extra loading with nil-wind reverse-launches.
The most remarkable thing in-flight is its handling, which is both swift and agile. The wing responds very well to the controls, which are neither too heavy nor too soft for the first third of the travel.
If you don’t flatten the turn with the outer brake, the wing swiftly increases it's angle of bank and if you keep pulling the inside brake it will start to enter a spiral without any sticking point in pitch. On the other hand if you counter-balance the turn with the outer brake, everything changes. This increases the angle of attack in turns and proves it to be an exceptional glider for thermalling, with enough feedback and resistance via the controls to void abusing the wing without realizing it, whilst at the same time not so much as to make it tiring.
In turbulence (for example, with winter thermals, with very dense, cold air), the centre of the wing may sometimes lose some tension and cause the wing-tips to curl in a little towards the middle. Instead of tucking from the front, it tends rather to cause a couple of cells to roll in from the tip. You just hear a rustling above your head, feel the wing move slightly but by the time you look up it has already popped back out.
|Extremely pronounced internal cell-structure. Open cells and high aspect ratio, streamlined for an advanced level 2 glider.
The speed system is light and it's effect very noticeable, with a clear net increase in speed even just in the first half of the travel, which then keeps on increasing without the leading edge feeling like it loses any solidity (with virtually zero creasing) so it seems that this [Security Speed] System which it's designer (Alvaro 'Waldo' Valdez) defends really works very well, although aesthetically speaking some of the reinforcements can be seen unloaded during normal flight.
The level of security is around the middle of the DHV 2 spectrum.
Inflation: Just right, doesn't overshoot or hang back.
Turn initiation: Immediate and direct.
Turn reversal: Responsive, agile banking.
Slow turn: Changes completely, docile.
Slow flight: Brake travel is long, firm at the end.
Normal flight: Fast and solid.
Fast flight: Marked acceleration.
Pitch: The centre of the wing may lose some tension.
Roll: Light or rapid depending on pilot input.
Turn: Responds well to the use of the outside brake.
Stall: Very low down, very unlikely to reach it accidentally.
Pressure: The wig tip occasionally tucks.
Dacron reinforcement in the leading edge.
Brake attachment point every 1.5 cells.
Floating secondary ribs.
Trapezoidal-shaped diagonal ribs.
Firm brake handle.
Two-level line layout.
Magnetic brake handle attachments.
Speed-system pulley travel: 16cm.
Plastic maillon line-tidies.
Speed-bar travel: 29cm.
Split A-risers for the speed system and big-ears.
Rectangular cell openings.
12 closed cells (at wing tips).
Central cell-opening: 24 x 11 cm.
Smallest cell-opening: 16 x 6 cm.
Cell widths: Reducing from 24 cm down to 16 cm.
Mylar webbing-tape reinforcement along the trailing edge.
Cloth: Nylon NCV Skytex E85A, E77A and E29A de 45 grs/m2.
Lines: Edelrid Aramide 1.1 - 1.3 - 1.5 - 1.7 and 2 mm.
Performance (Tempest 27)
||108 kg (3.99 kg/m2)
|speed at minimum sink-rate (50% brake)
|speed at maximum glide
||1.1 m/s at 32 Km/h
||approx. 8.8 at 38 Km/h
Test conditions: at 1300 m QNH and 2º C, (Skywatch Pro and Compeo).
|projected area (m2)
|projected span (m)
|projected aspect ratio
|max chord (m)
|med chord (m)
|min chord (m)
|line length (m)
|canopy weight (kg)
|all-up weight (kg)
Designer: Alvaro Valdés.
Manufacturer: Windtech (Gijón, Spain).