The PRO-DESIGN Effect
Reviewed by Greg Hamerton - 25 April 2002

My prior experience with Pro-Design’s workmanship was the Compact (DHV2) with which I learned to fly xc, and the Pro-Feel (DHV2/3), with which I chased competition gaggles across thermic checkerboards. I enjoyed both gliders immensely. Then I reviewed the Target, and didn’t enjoy the overly-reassuring feel. The recent Pro-ject (DHV2/3) got me interested in Herbert Hofbauer’s range again. Now the Effect (DHV1/2 March-Aug 2000) has re-established my faith in Pro-Design. I wish I’d flown it sooner - this wing deserves attention.

Construction : One thing you can always notice in a Pro-Design wing is the attention to strength during construction. Triple-stitched seams, thick risers, thick centre lines, everything that goes into making Pro-Design the toughest kid in a rough neighbourhood. It’s what we like to see in South Africa, where everyone knows what UV means (that’s them harmful ultra-violet rays, you sheltered northern children ;-). All Pro-Design wings have an impressive 3year / 400hours warranty. The attractive undersurface swish used on the Pro-ject is now the standard pattern on the Effect.

The backpack is big enough and durable, but the crimping tension is unfortunately transferred to the zips. It was also a bit too flexible and unconfined for my liking.

Launching : The Effect has an easy, steady, light but fairly slow pull-up, showing no tendency to overshoot or lag behind.

Handling : Turns superbly. It is sensitive to small brake inputs, and yet it does not have a lot of retained energy in turns, a combination which is great for intermediate pilots, and is difficult to achieve. Turns are by default fairly flat and efficient. The Effect seems responsive to weight-shift, but without brake input the wing does not turn much, again a rare combination of sensitivity and roll stability which is lacking in many other wings. I found thermalling a pleasure, with easy smooth turns, and a precise feel. I knew exactly what the wing was going to do, and could direct it at will. Big brake inputs resulted in a turn tight enough to hook into narrow passing thermals.

Many of the intermediates I’ve flown have been either too rigid to generate good roll-overs, or they’d do good rolls but were too ‘loose’ and active for most pilots in the class. The Effect strikes a lovely balance. Acro is now within the reach of the ambitious apprentice, on a wing which will be reassuring for those who prefer the horizon to remain level.

The Effect is limited in the pitch axis, meaning that when flying through an active sky, there is little need to haul back on the brakes every time the wing recovers from sudden updraughts. If the Effect does pitch forward, it is self-limiting, dampened.

Although there is good feedback from the wing, it is not so much that you are upset in your harness or feel the need to have your ‘finger on the brake-trigger’ all the time. You are told what the air is doing in a gentle, reassuring voice, the wing doesn’t do much - it’s up to you what you do with the information.

Performance : Excellent glide. I caught an Apco Futura tandem glider ahead of me over five minutes without losing any glide relative to it. I was using 3/4 speedbar, they were at trim speed. Such performance is exceptional, when you consider that a wing is never at its best when accelerated. I have watched an Effect hold its own alongside my Magic (DHV2/3) for a long stretch during an xc flight. You don’t have to worry about performance – it is top notch. You might have believed that something released in 2000 can’t be competitive in 2002. I disagree - if anything, the Effect was ahead of its time.

Flying the wing very light (92kg) I found a 36km/h trim speed, which is comfortably high. The linear speedbar system took the Effect to 47km/h, although the last quarter of the bar is only advisable in smooth conditions as it deforms the nose slightly. Greater accelerated collapse resistance would probably be found by flying higher in the weight-range. The bar pressure is fairly high due to a 2:1 pulley effect on the A’s (total 16cm shortening), but the bar-travel is conveniently reduced so you don’t really need the second step on the speedbar.

Safety : You should not be having collapses. I know that might sound idealistic, but I believe it is possible to fly an entire summer thermic season and not have one major collapse on something like the Effect. But if you do nothing to help it actively (to ‘gather the slackness in the nose’ by reactive application of the brakes) then you will be relying solely on the DHV test behaviour. Rest assured, the Effect 36 has only one 1-2 score (for the accelerated front tuck) where recovery is spontaneous, delayed, with slight tendency to overshoot. So I would say the marketing campaign as a DHV1 (‘1-2 when accelerated’ written in small print) is fair. It’s as safe as you can get.

Most of the big asymmetric collapses which I induced reinflated spontaneously within one second, an impulsive, 'smack-out' inflation which resulted in a return-swing that brought me back to my original course. Although it is surprisingly quick, there is no doubt at all that the Effect opens. For those collapses which didn’t reinflate so suddenly, the wing seldom turned more than 90 degrees. Countersteering is simple, and although the wing slows noticeably, it did not try to stall.

Big front tucks open firstly in the centre of the wing, with the tips tucked. The wing passes through a mild stall phase, then regains airspeed and reinflates spontaneously. It is best to allow the Effect a few seconds to clear itself before pumping out any obstinate deflation.

Standard big-ears are easy to reach thanks to the bright yellow ‘extension lines’ which are secured about half-way down the risers. Although I couldn’t induce a stall while under banked large ‘big-ears’, the angle of attack felt high, and the wing did slow, so I would just mention some normal flying advice - extremely large ears should always be done with a touch of speedbar applied.

B-lines are simple to enter, but should be released quickly to avoid a slightly delayed recovery.

Stall point is at your seat level. Full stall drops far back, the wing reinflates simply, and surges ahead on recovery. It is possible to keep the wing in parachutal / deep stall with only a small amount of brake applied, so be sure to allow the wing time to regain full airspeed before turning after B-lines, front tucks or gust stalls.

Spin resistance is high, the Effect prefers to give a tight, banked turn instead.

Conclusion : The Effect replaces my long-time favourite, the Arcus, as the best intermediate wing to sell to the Basic-licence-graduate and cross-country enthusiast alike. It makes an ideal bivouac wing, ably proven by Chris Scammel (read about his 830km Alpine trek on the Pro-Design website). It is easy to launch, effortless to fly. It has the kind of performance which makes most DHV2 and 2/3’s look a little suspect. (It’s difficult to justify flying with less stability when the damn DHV1 is keeping up with you!) Combine that performance with Pro-Design’s meticulous manufacturing quality, and you have the recipe for something truly special.

TECHNICAL SPECIFICATIONS :
For more information visit the Pro-Design website http://www.pro-design.at
Many thanks to the Pro-Design importer for the wing :
Jo Chananie +27 (0)82 904 1020 or +27 (0)31 2665774
email aviotec@iafrica.com

* Note : Multiply by the correction factor to scale the results to a standardised condition of 1000m altitude, 15 deg.C air and a pilot at the maximum certified weight limit (assumed roughly 3% increase in speed per 500m, 2% increase per 5 deg. C and 2% increase per 5kg extra weight). Humidity and turbulence could cause further variations from the standard. I use a fifteen-second average to provide 'highest sustainable speed'.