FLIGHT DESIGN S2 VT: Magical!
By Noël Bertrand
In "Vol libre", August 98, page 9-11
The most pleasant wings these days are just good ol regular wings. Nevertheless, they kick ass! The S2 VT is one of those.
And once again
Well, every year Flight Design comes up with a wing that sets the standard against
which other companies need to measure up! After the B4 VT, an advanced pilot wing, and the
A6 VT in 1997, a very accessible and very fast intermediate wing, here comes in 1998 a
beginners wing: it is rated, depending on the way the brakes are set (long range of
motion, vs. less range of motion), as a DHV 1-2 (first wing) or an AFNOR Standard. The
Germans refer to it as a "Sport Class Glider." Flight Design has always broken
new ground, and has been quite successful in building up its market share in the
paragliding world, then in the Ultra Light Motorized world with the CT, and now in the
world of rigid wings, with the famous Exxtacy. The stereotypical image of demanding
Germanic workmanship fits perfectly this inventive and very well managed company, that
re-invests a lot into the sport. Matthias Betsch is an enthusiast who loves to challenge
himself to excellence. He knows how to hire the best designers, the best marketers and the
best salesmen. To manufacture the wings, the best they hired used to be the Chinese loft,
Laminated Products. As reported by Christoph Blezinger, that company let go of its
paraglider manufacturing group: Flight Design then simply went to their neighbor, Aeroman,
who is also very well recognized in the industry (Paratech, Swing, etc.) Aeroman took over
the production unit from Laminated, and also hired a number of their seamstresses; this
way, they didn't loose the built-in know-how, and they managed to ensure a smooth
transition for their clients. Aeroman aims for zero-defect, and their quality control is
one the strictest in the paragliding industry. Nothing "average" slips through
their multiple checkpoints!
First impression
Flight Design kept their strong black bag, a no-nonsense thing that borders on the pedestrian. It is decorated with the logos that we, at Vol Libre, still find quite esoteric, but that the initiated see as mere nice geometric shapes . . . The volume is adequate for traditional gear with an airbag, but somewhat on the small side to comfortably swallow a big mousse-bag, because of its vertical orientation (as an offset, that shape makes it comfortable to hike with.) It offers a big front pocket, and the traditional top and side handles. No padding on the belt, nor on the back, so you must pack your wing carefully to keep the soft stuff against your tender back.
The wing is made of 48g/m2 Teijin polyester for the upper surface, and 38g/m2 for the lower surface. It comes with a strap and a stuff bag. All the cells are open, except those on the wing tips, and are hemstitched. The cells are wide, and doubled up. A system of diagonal reinforcements in a Y-shape, lined up on the As and the Bs, equalizes the efforts in traction between the cells that have lines attached to them and those that dont. The front part of the main cells are rigidified with a Dacron braid. The stitching for the cells that dont have lines attached to them is external both on the upper and the lower surfaces, so they need to be checked carefully when the wing is often used on abrasive surfaces, like sand, snow, rocks, The center of the wing is marked both at the leading and the trailing edges. The trailing edge is reinforced with a stitched Mylar braid. The five risers (the As are split to help pull in ears) sport the traditional Flight Design color markings: As are red, Bs are yellow, Cs and Ds are purple. The double-pulley speed system, with 21cm between the pulley axis, first pulls the As for 1 cm (less than 1/2 inch) and then the As and Bs together and pulls the Cs 50% of what the A's and B's are pulled . There are only three lower lines for each side of the glider. One line is attached to the outer A riser for Big Ears. The lines cascade upward with the traditional three trees. They are made of Aramide manufactured by Cousin, in 2.2 mm for the main ones, then 1.1 mm for the upper.
The straight trailing edge like in a B4 or A6 makes the S2 VT a true Flight Design wing! This typical "Dorner" shape was named "TNT" system (which stands for Tragflugel Neuer Technologie.) You cant miss the flashy neon color schemes. The wing is very well finished: for example, there are some very serious reinforcements where the lines attach to the wing, they glued some round patches to reinforce the points where the stitches start at the leading edge, the end of the lines are all melted and are well stitched to secure them, etc.
All this spells "p-l-e-a-s-u-r-e!"
I land and hand over the P7 to Jean-Gabriel Thillard, a pro pilot from Grenoble. He gives me back the S2 VT; judging from the mosquitoes stuck to his teeth (yuck!), he had a great time with it! The conditions for the test are strong. 7 to 8 m/s lift, with a North wind, at Courtet, in the Obiou mountains. Typical conditions for this launch. The lines are easy to straighten out. I grab both As at the quick links, sets my elbows on my sides and the wing scoops up the air and goes up very quickly. The S2 doesnt overfly its pilot. When the wind is light, there is very little pressure in the brakes, but the wing still goes up very quickly. The pilot must use some sensitivity and finesse to stay well centered under the wing if it didnt go up perfectly symmetrical. You get if just fine after doing it three times, but all the same that trait keeps the S2 VT from being a "mere school wing" -- Flight Design never claimed it was one anyway. The wing starts flying after three steps.
On our test wing (brakes set for the "Standard" rating), the setting of a turn is perfectly proportioned to the range and to the strength of the pull on the brakes. With the brakes down 15 cm (6 inches), the wing flies at 30 km/h. The whole range needed to pilot the wing covers 20 cm (less than 8 inches.) The wing responds instantaneously, with no inertia nor inverse yawing. Turns are very homogeneous, yaw and roll stay well in synch by themselves. The pilot can control the turn very precisely with the outside hand. It is a true pleasure to work a thermal or weak ridge lift with such a tool. The pilot doesnt need to weight-shift. Everything just comes together by itself! Exemplary and easy to handle behavior because, whatever the technique the pilot chooses to use, it works just fine. It feels like you only need to think about the turn and the wing cranks it for you, perfectly.
Roll is dampened progressively and very well, considering how easy the wing is to control and how smooth it is to turn. Pitch, handled with brakes in such strong conditions, is also well dampened. No tendency to surge when leaving a thermal. The wing speeds up very quickly, with a speed bar that requires two rungs (and long legs): 36 km/h, hands up, and 47 km/h with the speed bar full on (Flight Design claims 47 km/h, the AFNOR measured 49 km/h at the minimum wing load, and 54 km/h at the 105 kg maximum wing load on the 26 model!) This makes the S2 VT the fastest "beginner" wing that we ever tested all this while still staying well stable.
When testing the other end of the polar curve, hands under the seat, the wing stalls frankly at 22 km/h, and then recovers with a nice and easy surge. With the brakes set for the "Standard" rating, it is possible to stall the S2 VT with the brakes, which again doesnt make it suitable as a "school wing."
Ears stay pulled in and reopen with brake input. The sink rate is then 3.5 m/s, with a forward speed of 35 km/h. It is very easy to use weight-shift to pilot the wing in this configuration. Overall performance is in keeping with what weve seen so far: it performs extremely well in all respects, and it is very easy to find the best glide simply by flying with hands up. The pilot must let the S2 VT "fly by itself" without bridling it in. We still measured a 6.3 glide ratio when flying at 47 km/h: very impressive for such a wing, that only boasts of a 5.2 aspect ratio The glide measurements that Vol Libre collected correspond to those announced by Flight Design, although the manufacturer is a little bit optimistic re minimum sink rate.
Conclusion
This wing brought a consensus among all the pilots who were lucky enough to try it, whether as a paraglider, or with a motor (risers with trims are available for powered flying.)
The S2 VT, as a beginner wing, is a perfect flying machine, fast, precise, easy to control, quick to turn, lively and easy to master: perfect to become a demanding pilot, truly well trained!
It is reliably sturdy in rowdy air, and behaves with a healthy soundness. Of course, it is always wiser and safer to abstain from flying with the speed bar full on when the air is rough, but even there, the S2 VT handles itself remarkably well, with a solid leading edge that, if it does start fluttering, tends to open back up on its own.
With this wing, Flight Design came up with something as revolutionary as the Astral Swing was in its time, which will explain why we are so enthusiastic about it! Those are the types of wing that totally convert pilots to the joys of Free Flight and instill in them the desire to go further. And that is exactly what we like here, at Vol Libre!