Tying Aircraft Down in Strong Winds

[Phoenix09]

I have just received a telephone call from my flying club telling me that they are expecting severe winds tomorrow of 70 - 90mph. At present my aeroplane is tied down facing, roughly, west which is the direction that the wind is coming from.

Is there a best way to park her. Should I leave her nose into wind with, what I would imagine would be, a fair amount of lift being generated by the wings or should I turn her round so that she is tail into wind? The aeroplane is tied down to steel cables that run the length of the parking line at the airfield.

[Kingy]

I would turn it tail into wind, but make sure the control locks are on nice and secure - Good Luck..!

I'm just off to check my hangar roof..:ooh:

Kingy

[stillin1]

Nervous times ahead!

Into wind - try to tie-down the wing-tips, once the breeze gets under the wings you've had it. Tie down the tail too if you can. sand bags (weight) on the wings will help, as they would in the cockpit too. Fill it wiv fuel too.

Tail on - beware the wind blowing the control surfaces and causing backlash through the control runs = damage. Control surface locks could help but will need to be v good to cope with the likely loads. Great direction for a tail dragger though cos the breeze will force the ac down.

Get it away from other ac + Flaps = up, when they flip it's nice if they miss yours (in a hangar is nice but, I bet you've thought of that and just called me a very rude name!).

Drink heavily

Good luck :cool:

[Phoenix09]

No excuse needed for me to drink heavily!

I should have said that the aeroplane is a Cessna 172 so a nosewheel.

Just off to get some rope to try and tie down the tail as well. It is already raining very heavily here at the moment so I think I shall be getting slightly wet! :(

[fu 24 950]

C172,, into wind and dig a hole for the nose wheel, lower angle of attack. C180 or other tail draggers , lift the tail on to a 12 gallon drum and tie well down, easier than digging the main's in. never tail into wind as this will cause alot of damage. Also some thing on top of the wing, sand bag etc to break up the air flow and lift.

[Monocock]

fu 24 950, that's a good idea and makes a lot of sense.

A very good way of protecting the a/c is purely to park something big in front of it like a minibus, van etc. This removes all direct wind and I have seen it working successfully several times.

These winds are going to be VERY strong, the Met Office are talking about "risk to life" now on their warning!

[Say again s l o w l y]

Definately into wind, NEVER Tail first in a nose wheel machine.. I've seen control locks snapped in two and control stops totally trashed before we got a chance to turn the a/c. That is not an experience I want to do again. Trying to turn a C150 in 60 kts of breeze! Luckily we had two tractors to act as windshields and even then we nearly lost it a couple of times.

Good tip from fu 24 950.

Tie them down well (no Granny knots!) and hope for the best...

[Kolibear]

There was an article on tying down in strong winds in Pilot mag. a few months back. The only advice I can remember was to place length of wood, 25mm square would do fine, along the wing at max. chord and secure with bungees. They act as spoiler and completely destroy any lift.

Thinking about it, the wood might have been larger than 25 mm square, more like 3x1 inch stood on its edge.

[FlyingForFun]

Depending on how you lock your controls, you may or may not have the flexibility to think about where to lock the elevator. If you're pointing a nose-wheel aircraft into wind, then try to make sure the elevator is as full back as possible, so that the wind will try to take the weight off of the nose-wheel.

Seem to remember a very long, detailed thread on this subject a long long time ago, but can't find it now. Anyone else remember it?

FFF
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[Tinstaafl]

Definitely into wind. Remember the a/c is designed to operate into a 'headwind' up to whatever its Vne is. It's certainly not designed to have a tailwind of any great amount.

A tailwind will try to move the surfaces hard against their stops. Repeatedly, suddenly & with force.

For nosewheel types consider tying down the nosegear** as well as the wing & tail tie-down points. Ideally the wind would always be a direct headwind. Of course that's not really likely, leading to some amount of lateral force(s). You could think about using more than one line to each point eg two at 45deg angle to the tail point etc. Ditto multiple lines to the wings.

Digging in the mains to reduce AoA is a good idea. Acts as chocks too. If not dug in then use chocks.

Spoilers are beneficial. Almost anything appropriately shaped that is robust enough not to fall apart under the wind load when secured to the upper surface will do. Make sure there's something soft between the spoiler/securing straps & the wing otherwise you risk stuffing the paint job/scoring the Alclad when the spoiler inevitably shifts about.

Don't agree with full-up elevator (nose wheel type). Full-up will cause a nose up pitching force under wind. What is the a/c's Va? Also if there's any slack in the securing then a slight pitch up will increase AoA with a resulting increase in Lift = more load agains the tie down points. Neutral control is better.

Reasonable for a tailwheel perhaps since it would help pin the tail. Still have to consider Va if really strong winds forcecast. Mind you, if the wind is that strong I'd consider relocating the a/c in advance of the wind's arrival.

If you have external gust locks then use them.




**Cessna recommend this and with good reason. I saw the results of a line of nosewheel types in a strong, gusty & quartering headwind flying on their tethers. Each time the wind dropped they'd have slapped back onto the ground with quite some side load. The whole row ended up resting on their chins. I suspect that the tie down line didn't help. It was one of those long steel cable affairs that pass under embedded hoops every couple of a/c positions. Too much slack available, I think.

That was a hell of a storm. The end result was:

2x C172s flipped sideways to land inverted on a Grumman AA5 each. They'd pulled out their stakes.

1xC172 flipped over its tail

The line of Cessnas & pipers with the busted nosewheels

A C310 rolled across the field. How it missed the large drainage ditches is beyond me...

A hangar destroyed. Major damage to the Buccaneer inside.

Another hangare totalled. The 4 C152s & 1 C172 that only just fitted using a particular layout were shuffled together enough that another two a/c could be fitted comfortably. Lots of damaged bits resulted.

In general, low wing types faired better than high wing.

Various other damages. What a christmas eve that was... :sad:

[IO540]

Is there any good way of estimating the max wind an aircraft can taxi in (in any direction)?