airbrake position while tied outside

Ah, what would life be without a controversy? Here's some conflicting
information to digest.

Open spoilers are rain catchers. Closed spoilers are not completely
sealed. If it rains, water will dribble in. If it rains hard and long,
the spolier box will slowly fill and at some point begin to spill
through the control rod access hole into the wing.

Solution, leave the spoilers closed and tape the seams. Or better yet,
get a set of wing covers.

BTW, I'm not sure putting the spoilers up wins you any net advantage.
It reduces the lift the wing is producing a little, but at the cost of
more surface area presented to the wind. The only real advantage I see
is that it accuates the wheel brake on many models. The key to
securing an aircraft for weather is no slack in the ropes. I suspect
deploying the spoilers is part placebo, a convenient "extra" for those
who are content to stick a pair of stands under the wings for the
night and call the glider secure.

Those contributors mentioning birds, beasts, and bugs also have a good
point. Taken in whole, I'd vote to leave 'em closed.

"Chris OCallaghan" wrote in message
om...
Ah, what would life be without a controversy? Here's some conflicting
information to digest.

Open spoilers are rain catchers. Closed spoilers are not completely
sealed. If it rains, water will dribble in. If it rains hard and long,
the spolier box will slowly fill and at some point begin to spill
through the control rod access hole into the wing.

Solution, leave the spoilers closed and tape the seams. Or better yet,
get a set of wing covers.

It is possible to have it both ways. If you really want to spoil the
lift of your wing while parked, you can make your own strap on spoilers of
padded wood or aluminum. Here in Florida, we get afternoon thunderbumpers
with winds that can briefly reach hurricane force. Over the years, I have
seen more than one glider get unnecessarily trashed. In addition to good
tiedowns, I like to see a moderately raised tail, and an extra tiedown
anchor for the tow hook.

Another issue that nobody has yet mentioned is the possible lack of UV
protection inside the spoiler box, this might be a good reason to keep
spoilers closed while tied down outside.

Vaughn

Chris OCallaghan wrote:

Ah, what would life be without a controversy? Here's some conflicting
information to digest.

Open spoilers are rain catchers. Closed spoilers are not completely
sealed. If it rains, water will dribble in. If it rains hard and long,
the spolier box will slowly fill and at some point begin to spill
through the control rod access hole into the wing.

Solution, leave the spoilers closed and tape the seams. Or better yet,
get a set of wing covers.

Rain is the major disadvantage of tying down with the spoilers open. If
I think rain is likely, I use some 2" foam pipe insulation that is
split lengthwise, place it over the spoilers, then use a bungey on the
spoiler handle to pull the spoilers down against the foam. The foam
seals the gap.

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change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

I think rain is likely, I use some 2" foam pipe insulation that is
split lengthwise, place it over the spoilers, then use a bungey on the
spoiler handle to pull the spoilers down against the foam. The foam
seals the gap.

Someone mentioned boards with insulation or aluminum to spoil the
lift. I'm a bit worried about damage to the surfaces. I
was thinking that some foam "hollow column shape" wrapping,
cut in half and put along the leading edge, might work for
this. Has anyone tried any of these three (boards, aluminum,
leading edge)?

This thread has pretty much run out, but I thought I would state that, if you
must tie down outside and expect high winds, four tiedown points on the wings
(in addition to tow hook and tail) are better than two, and if the only inboard
location on the wing happens to be inside the spoiler box, use what you got. I
use this location on my ship when tying down overnight on wave days (it's
easier to tie down than derig in 20+kts wind!), but know that I must vacuum the
sand and gravel out of the bottom of the spoiler box in the morning. It's
amazing how large of a grit size the wind will make fly two or more feet off
the ground, especially considering it comes from beyond the edge of our paved
ramp 300 feet away where the dirt ends. The spoilers are only held open less
than 1/4 inch with my setup, which consists of a large metal hook that goes
around the chordwise pivot in the spoiler box, then a 2" wide strap to get over
the LE of the wing, then rope attached to the strap for ease of knot tying.
The spoiler cap closes on the strap and traps the hook in place even if the
rope becomes loose.
As an aside, if there is an insurance claim for wind related ground damage, the
insurance company will only want to know if the aircraft was "tied down" and
what it was tied down to, they are not likely to deny the claim if you used
three ropes where five was needed. But you might be unpopular with the owners
of the other aircraft that yours flipped over on top of!
Ropes with non-slip knots, tied up tight against the rings or cables at both
ends, beat ratchet or cam-lock straps for simplicity and durability, and if
they do loosen in the wind, there is no hardware to flap around and trash your
gelcoat or paint.
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Mark Navarre
ASW-20 OD
California, USA
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