Demonstrated X wind a pointless figure ?
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To taxi back, you have to turn around and taxi with a tailwind.
Some taildraggers, really, really do not like to taxi in strong tailwinds.
Some taildraggers, really, really do not like to taxi in strong tailwinds.
Consider the position of the elevators and think what is going to happen in
a good tailwind. The instinctive reaction when the tail lifts is to haul back
harder. BAD MOVE.
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Many pilots hold the stick back while taxing to keep the tail on the ground
Consider the position of the elevators and think what is going to happen in
a good tailwind. The instinctive reaction when the tail lifts is to haul back
harder. BAD MOVE.
Consider the position of the elevators and think what is going to happen in
a good tailwind. The instinctive reaction when the tail lifts is to haul back
harder. BAD MOVE.
The real problem comes when you taxi a taildragger that has no brakes, in a strong tailwind that overcomes the slipstream you put left rudder on, what happens?
One solution is a burst of power, but remembering that you are being pushed along by the tailwind anyway this might not be such a great idea, this is why you will often find aircraft such as the Moths with wing walkers in strong winds.
Last edited by foxmoth; 8th Feb 2016 at 08:09.
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Stick back in a headwind, and stick forward in a tailwind is not the main problem.
On older aircraft, even with some of the tailwheel Jodels, it is directional control that becomes an issue.
Most have a flying rudder, and the mainwheels are rather close together, so you can not count all that much on the brakes either. (Certainly when they still have the old style drum brakes.)
On older aircraft, even with some of the tailwheel Jodels, it is directional control that becomes an issue.
Most have a flying rudder, and the mainwheels are rather close together, so you can not count all that much on the brakes either. (Certainly when they still have the old style drum brakes.)
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I would agree that there are a few older "certified" taildraggers out there for which ground control in strong winds would be a challenge. I would think that none of these aircraft were manufactured recently enough to be provided with a flight manual stating a demonstrated crosswind value. Other non certified types are on their own, so to speak, as they would not have an approved flight manual at all.
Those aircraft are from an era which predated the design requirements that explicitly stated directional control.
My certified taildragger can be landed in a direct crosswind of 19 knots, which exceeds the approved flight manual value of 12 knots, but experience has shown me that taxiing in that strong a wind will be difficult, and on ice, impossible. During my crosswind experimentation on a frozen lake, I found that the rudder became ineffective at speeds slower than around 10 knots with power off, so if there was no tailwheel friction to the surface, I was going to be blown around.
Those aircraft are from an era which predated the design requirements that explicitly stated directional control.
My certified taildragger can be landed in a direct crosswind of 19 knots, which exceeds the approved flight manual value of 12 knots, but experience has shown me that taxiing in that strong a wind will be difficult, and on ice, impossible. During my crosswind experimentation on a frozen lake, I found that the rudder became ineffective at speeds slower than around 10 knots with power off, so if there was no tailwheel friction to the surface, I was going to be blown around.
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To taxi back you have to turn around?
No you don't.
If it is really hairy, just sit there, and ask the tower to send a couple of blokes to push you backwards to the apron or other safe place! Works for me.
If it is really hairy, just sit there, and ask the tower to send a couple of blokes to push you backwards to the apron or other safe place! Works for me.
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Thanks for that flybymike.
Therefore, we have a visual/tactile indication of crosswind strength with both approaches. Are there any numerical rules-of-thumb that can be applied/derived w.r.t. amount of 'crab' and/or 'slip' required to hold the centreline? ie x deg drift = y kts crosswind.
(I realise as I'm writing this that this is simple wind-drift stuff or 'geometry' as Genghis pointed out! Apologies if i've learnt it for exams and forgotten it subsequently).
But couldn't the cross-controlling forces required to hold steady? at varying bank angles simulate a crosswind and therefore measure rudder authority or is that too simplistic?
Have I got this wrapped round my neck- could somebody unravel it for me please?
Thanks in advance
....if it was not possible to maintain the extended centreline whilst making an unbalanced wing down approach (I.e. not a balanced crabbed approach) without being blown off to one side, then unless the crosswind component diminishes in the flare and hold off (as is often the case) then the final outcome is unlikely to be a success.
(I realise as I'm writing this that this is simple wind-drift stuff or 'geometry' as Genghis pointed out! Apologies if i've learnt it for exams and forgotten it subsequently).
But couldn't the cross-controlling forces required to hold steady? at varying bank angles simulate a crosswind and therefore measure rudder authority or is that too simplistic?
Have I got this wrapped round my neck- could somebody unravel it for me please?
Thanks in advance
Last edited by jjoe; 8th Feb 2016 at 18:08. Reason: poor diction
[
If it is really hairy, just sit there, and ask the tower to send a couple of blokes to push you backwards to the apron or other safe place! Works for me. ][/QUOTE]
If I did that after INVERNESS ATC had slotted me in between scheduled traffic, I'd create havoc.
My suspicion is that castoring main wheels would be like the situation described on ice. Did they have a locking mechanism after landing?
If it is really hairy, just sit there, and ask the tower to send a couple of blokes to push you backwards to the apron or other safe place! Works for me. ][/QUOTE]
If I did that after INVERNESS ATC had slotted me in between scheduled traffic, I'd create havoc.
My suspicion is that castoring main wheels would be like the situation described on ice. Did they have a locking mechanism after landing?
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Don't worry, Maoraigh, I've only done it twice. The first time at the home gliding club...most landings are followed by pushing the aircraft out of the way!
The other time, Haverfordwest wasn't busy at all, the wind was so strong, we had just ridden it back from Ireland, this was just after I had made a prat of myself at Kerry, and didn't dare risk a repetition!
The other time, Haverfordwest wasn't busy at all, the wind was so strong, we had just ridden it back from Ireland, this was just after I had made a prat of myself at Kerry, and didn't dare risk a repetition!
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Jjoe, just fly your body down the extended centreline using either wing down or crabbed dependent on your preference or however you are taught. Rules of thumb are not really possible since drift, bank angle and rudder authority will depend on wind, airspeed and individual aircraft design. If you are looking at the runway out of a side window on a crabbed approach, or looking straight ahead with one wing scraping the tree tops on final then you can have some idea of the crosswind component and also expect an interesting arrival. An actual wind check from the ground would also be more than helpful of course.
If you carefully check the weather before flight and gradually build experience you will eventually figure out what you can and can't deal with and what might even require a diversion to an into wind runway.
We all get nasty frights from time to time. E.g in my case, a completely uneventful landing when it's blowing a hooley which you were well prepared and psyched up for, and virtual carnage because of a 6 knot crosswind which you considered irrelevant
If you carefully check the weather before flight and gradually build experience you will eventually figure out what you can and can't deal with and what might even require a diversion to an into wind runway.
We all get nasty frights from time to time. E.g in my case, a completely uneventful landing when it's blowing a hooley which you were well prepared and psyched up for, and virtual carnage because of a 6 knot crosswind which you considered irrelevant
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a completely uneventful landing when it's blowing a hooley which you were well prepared and psyched up for, and virtual carnage because of a 6 knot crosswind which you considered irrelevant
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When we were discussing rudder authority and holding the centreline I was purely clarifying that aircraft are flying a centreline tracking say a VOR at altitude with much stronger winds
Often far worse than the actual crosswind is the gusts and shear hence the comments about more speed equalling more control authority!
Once on the ground taxiing we have no control authority and are now driving a land machine with wings which are still prone to lift from the wind!
Some pilots I have known from the past have flown machines where the wind speed has equalled the takeoff speed and a sudden drop change could have disastrous results
We also talk here about tail draggers which will by their nature be far more prone on the ground
Pace
Often far worse than the actual crosswind is the gusts and shear hence the comments about more speed equalling more control authority!
Once on the ground taxiing we have no control authority and are now driving a land machine with wings which are still prone to lift from the wind!
Some pilots I have known from the past have flown machines where the wind speed has equalled the takeoff speed and a sudden drop change could have disastrous results
We also talk here about tail draggers which will by their nature be far more prone on the ground
Pace
