Primarily for general aviation discussion, but other aviation topics are also welcome.
By johnm
FLYER Club Member  FLYER Club Member
#1613010
Our TB 20 has been left sitting chocked on the apron at Alderney in 60 kt winds. As long as the control lock is properly fitted it's configured in nose down trim so it just nods down slightly in really strong gusts.
By Lefty
FLYER Club Member  FLYER Club Member
#1613019
johnm wrote:Our TB 20 has been left sitting chocked on the apron at Alderney in 60 kt winds. As long as the control lock is properly fitted it's configured in nose down trim so it just nods down slightly in really strong gusts.


It's satisfying to have one's opinion confirmed by an acknowledged expert on the type :D
#1613027
It's always a good idea to minimise the risk. You sleep better in your tent at night.
It might be a good idea to 'Google Earth' your destination and see where other aircraft are typically parked. If parking outside, I always try to put the aircraft in the lee of a building, or trees. On some aircraft (taildraggers), the Pilot's manual recommends parking tail into wind. So check the forecast and what the book says. If you are obliged to park on hard standing with no tie-down points, take along a two or three 20-litre folding water carriers (camping kit). On arrival, fill with water and wheelbarrow to your parking position. Tie to the aircraft. That will give you 60 kg weight, and sufficient for a brew of tea in the morning.
#1613042
If you do wish to have a bit of grass to bang the claw into then I can recommend Perigueux (up the road from Bergerac).

If you look at the airport in Google Earth you'll see that visitors park opposite the hangars but pushed back to overhang the grass. Last time I was there for a few days I tied down in such a fashion using the claw. Friendly place too. As previously stated fill up on arrival.
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By skydriller
FLYER Club Member  FLYER Club Member
#1613043
golfcharlie wrote:If you are obliged to park on hard standing with no tie-down points, take along a two or three 20-litre folding water carriers (camping kit). On arrival, fill with water and wheelbarrow to your parking position. Tie to the aircraft. That will give you 60 kg weight, and sufficient for a brew of tea in the morning.


Can you expand on how a 60kg weight attached to an aeroplane weighing significantly more and designed to carry significantly more than 60kgs into the air at a given airspeed is going to make any difference in the sorts of wind that might actually move an aeroplane?

The only thing that you might be able to carry with you to prevent an aeroplane moving in any really significant wind you would worry about is some kind of lift spoiler on the wings, or a proper tie down.

Regards SD..
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By foxmoth
FLYER Club Member  FLYER Club Member
#1613088
Can you expand on how a 60kg weight attached to an aeroplane weighing significantly more and designed to carry significantly more than 60kgs into the air at a given airspeed is going to make any difference in the sorts of wind that might actually move an aeroplane?


It is a question of moments, 60kgs in the cockpit will make little difference, at the tie down points, probably 2/3 outboard it will have a lot more influence, especially for wind getting under the wing, even better if they could put the tiedowns at the wingtip!
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By skydriller
FLYER Club Member  FLYER Club Member
#1613103
I'm afraid that many years in another field means my poor brain computes slower than it did when I studied Aero and I remain to be convinced that 30kg on each wing 2/3rds of the way out will prevent your aeroplane moving any more than doing nothing but chock and lock .... I doubt it makes things worse though I suspect that the real factor in whether your aeroplane does actually flip is the direction the wind hits it, and that is why tiedowns work.

Regards, SD..
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By flybymike
FLYER Club Member  FLYER Club Member
#1613111
Flyin'Dutch' wrote::?:

Shirley it males no difference where the mass is?


Think of it in terms of a lever Frank.

If you are trying to lift up one end of a see saw and a person is sitting in the dead centre of the see saw then it will make practically no difference to your ability to lift it, but if that person is sitting at the end you are trying to lift then you probably won’t be able to lift it at all.
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By flybymike
FLYER Club Member  FLYER Club Member
#1613134
For structural strength reasons.

Weights at the tips would theoretically be most effective, but if the aircraft “wants” to lift, then the mass on the wing tip (the weakest structural point) would threaten the integrity of the wing.

Just outboard of the centre of the span where struts would often be fixed is probably the best compromise point.
By cockney steve
FLYER Club Member  FLYER Club Member
#1613182
Like @johnm said, destroy the lift and you then only need to restrain horizontal movement. AIUI you can make or buy wing-covers that incorporate profiled foam strips to modify the profile. Racing-cars have long-used aerofoil "spoilers" to strongly push down and thus stick the vehicle very firmly to the deck. much better, safer and less strenuous than carting weights and/or spikes around. There have been cases of aircraft taxiing and taking-off, trailing their "tie-downs"

Not rocket-science to understand that an aircraft that will legally carry 2 people at ~10,000 feet (thin air, remember? ) and fuel., will actually carry a damned sight more (C150? AIUI, virtually all school-machines are operated overweight)

So, you need the weight of about 6 persons to have any hope of restraining even a small machine.
(around 1/2 a ton! )