For more on wings, see
Chapter 26: Choosing A Wing | and
of Reflex Wings |
Pylon Race Collapse Accident
All wings are more dangerous with
the speedbar fully engaged. Reflex wings, however, are only dangerous in
that configuration if you use their regular brakes, then all bets are
off. Even standard wings suffer this same problem; enough that
competition free flyers on full speedbar will frequently use rear risers
instead of the brakes for small turns.
All wings should be flown according to their owner manuals but this
article was inspired by the common use of reflex wings in competition --
a use that drives pilots to push outside the envelope. Those who like to
fly fast, which reflex wings do brilliantly, must be paid even more
attention to. If you're a new pilot wanting to get into flying fast and
maneuvering, team up with an experienced pilot who knows these wings and
To reiterate, one of the most important things to remember
about reflex wings is this: if you're fully accelerated and on
speedbar, using the regular trailing edge brakes is destabilizing
and makes a front tuck dramatically more likely.
Read that again. Every reflex wing designer or representative I've
ever talked to has told me this. While they may "allow" brake use with
some speedbar they acknowledge that risk goes up. And most of them put
that fact clearly in their user manuals. Also realize that sand in a
wing is like pulling some amount of brake. Plus it can cause a flutter
that has undetermined affects, especially at high speed.
I'll admit to an experience I had while reviewing the Dudek Hadron,
for which I had not read the full manual. I assumed that I could use the
trailing edge tip steering while trimmed fast and fully accelerated.
When I went up to fly it, that resulted in an immediate tip collapse. I
did it several times with the same result. Nothing dangerous, actually,
but certainly not what I expected and no way to turn the glider. So I
landed and asked an owner. His response: "oh yeah, that's stated in the
manual, you have to use the stabilo steering (they call it "ALC") when
fully accelerated." Ahhh. This glider has regular brakes, stabilo
steering AND trailing edge tip steering . The tip steering goes out to
the outer brake lines but you can't use it at full speed like you can
with some other reflex gliders.
I flew the wing again a few weeks later and solved the problem. Just
like the manual says, don't go all out with trims and full speedbar;
rather experiment to see how much trim you can let out and use full
speedbar. For me, about 2/3 fast trim allowed full speed although I
would occasionally take small tip collapses when going through my own
wake or slipping a bit while turning.
Pascal Valee, a world champion competitor who flies this wing, says
that he primarily uses the stabilo steering (ALC) when fully accelerated
to minimize his collapse risk. I have recently purchased an Ozone Viper
18 which has tip steering lines that go to the outer two brake line
attachments and it's OK to use when flying full speed and on other Dudek
models it's OK to use the trailing edge tip steering when fully
accelerated. Know the difference.
The most important point is to fly within the guidance of
your wing's manual and, if you don't have a manual, consider
yourself a test pilot. Go up high, with a reserve, preferably over water
with floatation, a coach and a boat nearby, and wring it out. If it's a
reflex wing, recognize that using brakes while fully accelerated is
putting you closer to collapse by some amount.
Secondly, know that just because you got away with it in practice
doesn't mean it's safe. You may have been within a hair of catastrophe
but never knew it. That's a finger I point right at myself since I did
just what Michael did although I did it up high and it wasn't as
Flying fast and maneuvering is indeed risky. Build up
to it slowly. Learn the gear, learn its limits, learn your own
limits and help us keep each other around for many years of bigList
debates and fly-ins.