Rudder Control
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Was it the Wright Bros who caused us pilots to have to learn to operate aircraft rudders in reverse? Did it come about because of the difficulty in crossing over the rudder control wires?
Three explanations for this .....
(1) You've been out in the sun too long mate
(2) The trauma of losing the RUWCF to the Poms has sent you temporarily insane
(3) Its the effect of a reversed Coriolis effect thru living on the other side of the world
Try this for size .... you want to hand signal a left turn on a bike ... you stick your left hand out... vice versa for right.
In a plane, you want left yaw etc etc....
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From: 58-33N. 00-18W. Peterborough UK
Final 3 Greens, Don’t be so dismissive! It is a fact of record that early aircraft, as a matter of course, had the rudder control reversed from today’s arrangement. Milt has simply noticed that today’s arrangement isn’t ‘natural’ – and I agree with him. You’ve simply got used to what you started with, and consider this the one and only way.
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Forget
I imagine that the sense of humour lobotomy that you experienced was a total success
If you wish to follow your logic, why don't we go back to propeller equipped trans atlantic airliners, using the telex instead of email and sacrificing virgins at the winter solstice to ensure that the days start to get longer after Xmas?????
It's called progress and the Luddites never liked it .............
BTW, what about differential braking? May be early aircraft didn't have that feature?
Milt and you would have us flying aircraft where we would have to apply rudder on one side and brakes on the other to get the same effect during ground handling - that should be a right larf in a gusty x-wind
Or would you arrange the brakes so that the right pedal worked the left wheel and vice versa?? Sounds pretty mad to me
I imagine that the sense of humour lobotomy that you experienced was a total success
If you wish to follow your logic, why don't we go back to propeller equipped trans atlantic airliners, using the telex instead of email and sacrificing virgins at the winter solstice to ensure that the days start to get longer after Xmas?????
It's called progress and the Luddites never liked it .............
BTW, what about differential braking? May be early aircraft didn't have that feature?
Milt and you would have us flying aircraft where we would have to apply rudder on one side and brakes on the other to get the same effect during ground handling - that should be a right larf in a gusty x-wind
Or would you arrange the brakes so that the right pedal worked the left wheel and vice versa?? Sounds pretty mad to me
Last edited by Final 3 Greens; 27th November 2003 at 06:49.
Joined: Sep 2001
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From: UK
Returning to the original thread.........
It is interesting to consider the sense in which the rudder should work in the context of aileron-rudder co-ordination (let us ignore aircraft where you never use the rudder in the air).
In the case of an aircraft with adverse aileron yaw, you apply left pedal with left aileron and vice versa, and most pilots will agree that this feels natural. If you have an aircraft that exhibits proverse yaw (it does occur in some aircraft that use spoilers for roll control), you apply right rudder with left lateral control, and for most pilots this feels very unnatural.
If we now consider a crosswind landing using the "crab and kick-off drift" technique, you generally need left aileron to hold wings level when using right rudder (i.e. with the wind from the left) and again most pilots find this co-ordination natural. Note that if an aircraft possesses lateral static instability (anhedral effect) then you would need rudder and aileron inputs in the same sense, which feels very unnatural.
So, the "natural" sense for aileron-rudder co-ordination varies according to the manoeuvre being flown. Basically, it is all down to a conditioned response, or what we have become used to as the norm. There is really no right or wrong. But thank goodness that we have standardised on one system for the sense of operation of cockpit controls (except for the nosewheel steering on weightshift microlights!).
My comments above on what most pilots (in fact all with whom I have flown) consider as the natural sense is not just hypothesis but is based on many hours of instructing in variable stability aircraft where such flying qualities can be evaluated.
I have heard an apocryphal tale that one of Messrs. Rolls or Royce once made a Ł1000 bet that he could drive a car 1000 miles with the steering wheel working in the "wrong" sense. Allegedly, he won the bet, jumped into his own car and slammed it into a wall! Can anyone confirm this?
It is interesting to consider the sense in which the rudder should work in the context of aileron-rudder co-ordination (let us ignore aircraft where you never use the rudder in the air).
In the case of an aircraft with adverse aileron yaw, you apply left pedal with left aileron and vice versa, and most pilots will agree that this feels natural. If you have an aircraft that exhibits proverse yaw (it does occur in some aircraft that use spoilers for roll control), you apply right rudder with left lateral control, and for most pilots this feels very unnatural.
If we now consider a crosswind landing using the "crab and kick-off drift" technique, you generally need left aileron to hold wings level when using right rudder (i.e. with the wind from the left) and again most pilots find this co-ordination natural. Note that if an aircraft possesses lateral static instability (anhedral effect) then you would need rudder and aileron inputs in the same sense, which feels very unnatural.
So, the "natural" sense for aileron-rudder co-ordination varies according to the manoeuvre being flown. Basically, it is all down to a conditioned response, or what we have become used to as the norm. There is really no right or wrong. But thank goodness that we have standardised on one system for the sense of operation of cockpit controls (except for the nosewheel steering on weightshift microlights!).
My comments above on what most pilots (in fact all with whom I have flown) consider as the natural sense is not just hypothesis but is based on many hours of instructing in variable stability aircraft where such flying qualities can be evaluated.
I have heard an apocryphal tale that one of Messrs. Rolls or Royce once made a Ł1000 bet that he could drive a car 1000 miles with the steering wheel working in the "wrong" sense. Allegedly, he won the bet, jumped into his own car and slammed it into a wall! Can anyone confirm this?
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From: UK
(except for the nosewheel steering on weightshift microlights!).
My argument about this earlier was that with everything working in the same sense, you condition to it naturally - problems may lay with opposing controls. This might be weightshift-style pedals with a conventional stick (as I mentioned with the Weedhopper), or for that matter push-left-roll-right-stick with conventional rudder pedals. Indeed, I know from experience that I can jump routinely between a conventional light aircraft and a conventional flexwing with no trouble at-all (having, I hasten to add, been properly trained and remained current in both).
I've been worked exceptionally hard by two aircraft which break those two "rules" - one was the American Weedhopper (stick and pedals in opposite directions, nosewheel), the other a French flying flea (no pedals - stick drives rudder - taildragger; so directional control in the flare is with the stick, opposing again all my conditioning about how to land a taildragger). However, both of these are types with excellent safety records (perhaps in the case of the flea I should say RECENT safety record), which suggests that neither control system is inherently bad.
So, (as I think Lomcevak is suggesting) are we all really making statements about our conditioning, and is the question really one of standardisation, or at-least any pilot being properly trained and remaining current on a particular control system combination?
But please, nobody try and put "conventional" nosewheel steering on a flexwing, that I'm really not sure that I want to try.
Incidentally I recently got the opportunity to fly the Rutan Starship 1 simulator, which I'd class as one of the most unnatural things I've ever flown. Not because of any particular characteristic, but because as you passed between modes of flight the control laws kept changing - which makes me think that perhaps the most "natural" aeroplane is the one which keeps behaving in the same way regardless of mode of flight?
G
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LOMCEVAK
The 'conditioning' you refer to is algorithmic learning - gained from demonstration by an instructor and reinforced by lots of practice.
It is a very powerful method of learning and the inevitable downside is that it is difficult to 'unlearn' at a later date, meaning that regression to prior learning, under stress, is a highly probable outcome when using a new system that requires different algorithmic responses.
David Beatty talks (in the Naked Pilot) about the transition issues experienced when BOAC moved from the Comet to the 707 (different landing techniques) and this is a perfect example of the syndrome.
In the most extreme of circumstances, regression can be fatal - so thank goodness that the control systems are mainly standardised as you say.
The 'conditioning' you refer to is algorithmic learning - gained from demonstration by an instructor and reinforced by lots of practice.
It is a very powerful method of learning and the inevitable downside is that it is difficult to 'unlearn' at a later date, meaning that regression to prior learning, under stress, is a highly probable outcome when using a new system that requires different algorithmic responses.
David Beatty talks (in the Naked Pilot) about the transition issues experienced when BOAC moved from the Comet to the 707 (different landing techniques) and this is a perfect example of the syndrome.
In the most extreme of circumstances, regression can be fatal - so thank goodness that the control systems are mainly standardised as you say.
Joined: Jan 2003
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From: Kelowna Wine Country
I was playing with a remote control video camera belonging to a friend the other day.
To pan left you push the stick to the left, Right for right, forward to pan UP, and Back to pan DOWN. I started with the control pod on my lap but I just could not get used to the up and down sense. It was a bit easier if I put the pod up against the face of the desk in front of me but I thought it would be much, much easier if it worked in the sense of a control column, forward to pan down etc.
Looked at in that way either the elevators or the rudder are indeed connected in reverse, it's just that is the way we are conditioned.
Interestingly the owner is a long time pro pilot but he could not even understand the point I was trying to make, that if we reversed the vert. control connection it would work the same as his plane!
I had no trouble at all chaging from a tiller to a wheel. When I steer with a tiller I sit side on to the forward motion. When I use a wheel I face the direction of motion. Like my pilot friend, for that at least, I have a separation of skills.
To pan left you push the stick to the left, Right for right, forward to pan UP, and Back to pan DOWN. I started with the control pod on my lap but I just could not get used to the up and down sense. It was a bit easier if I put the pod up against the face of the desk in front of me but I thought it would be much, much easier if it worked in the sense of a control column, forward to pan down etc.
Looked at in that way either the elevators or the rudder are indeed connected in reverse, it's just that is the way we are conditioned.
Interestingly the owner is a long time pro pilot but he could not even understand the point I was trying to make, that if we reversed the vert. control connection it would work the same as his plane!
I had no trouble at all chaging from a tiller to a wheel. When I steer with a tiller I sit side on to the forward motion. When I use a wheel I face the direction of motion. Like my pilot friend, for that at least, I have a separation of skills.
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From: Cambridge, England, EU
To pan left you push the stick to the left, Right for right, forward to pan UP, and Back to pan DOWN.
When I steer with a tiller I sit side on to the forward motion.
Joined: Sep 2001
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From: UK
Final 3 Greens,
Thanks for the detail on my comments. The psychology of flying fascinates me.
Genghis,
I have done only a few hours in weightshift microlights, many years ago now, but still after several thousand hours in "conventional" 3-axis control aircraft of various sizes. I found that there were conceptual differences between operating the nosewheel steering pedals and moving the 'A' frame. The pedals appeared to me to be philosophically the same inceptor as in a 3-axis machine, albeit working in the opposite sense. However, the 'A' frame was a totally different concept to a stick or yoke type of control column in that a. the pivot point was above you and b. your body moved with respect to the wing, which was rigidly attached to the inceptor (rather than your body being "rigidly attached" to the whole airframe, and the inceptor moving relative to both). As a result, I had no tendency to make pitch or roll inputs in the wrong sense, but had monstrous problems with regression when high gain yaw inputs were required. Interesting stuff.
Rgds
L
Thanks for the detail on my comments. The psychology of flying fascinates me.
Genghis,
I have done only a few hours in weightshift microlights, many years ago now, but still after several thousand hours in "conventional" 3-axis control aircraft of various sizes. I found that there were conceptual differences between operating the nosewheel steering pedals and moving the 'A' frame. The pedals appeared to me to be philosophically the same inceptor as in a 3-axis machine, albeit working in the opposite sense. However, the 'A' frame was a totally different concept to a stick or yoke type of control column in that a. the pivot point was above you and b. your body moved with respect to the wing, which was rigidly attached to the inceptor (rather than your body being "rigidly attached" to the whole airframe, and the inceptor moving relative to both). As a result, I had no tendency to make pitch or roll inputs in the wrong sense, but had monstrous problems with regression when high gain yaw inputs were required. Interesting stuff.
Rgds
L
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From: UK
b. your body moved with respect to the wing, which was rigidly attached to the inceptor
Considering the number of things I've flown since, it's perhaps surprising that this fundamental difference hasn't subsequently given me trouble. My best explanation for this is that the environment becomes totally different and my "learned response" when presented with a flexwing seat, panel and basebar acts consistently in a particular manner - whilst if strapped in with a stick in front of me and a high instrument panel I'm "conditioned" to behave in another.
G
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Joined: Oct 2003
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From: Canberra Australia
Control Standardisation
Now that many of you have been through ab-initio on rudder control and many other interesting aspects re instinctive control, consider :-
The wing sweep control for the F-111 is a fore and aft slider on the left side of the crew module. Should you slide the control forward to sweep wings back, for higher speed, or the other way round to correspond to to wing movement?
GD had it one way to start with and then changed their mind.
Then an interesting aspect on the use of elevator trim tabs.
Friend was SO close to being caught out with an unintentional beyond aft limit cg. On take off nose pitched up and was hardly held with full forward stick and trim. Increasing speed regained enough elevator power to overcome pitching up. But reflect on this as it might save your skin someday.
He had enough strength to hold stick forward to the stop. Then he should have wound on nose UP trim providing him with increased elevator.
The wing sweep control for the F-111 is a fore and aft slider on the left side of the crew module. Should you slide the control forward to sweep wings back, for higher speed, or the other way round to correspond to to wing movement?
GD had it one way to start with and then changed their mind.
Then an interesting aspect on the use of elevator trim tabs.
Friend was SO close to being caught out with an unintentional beyond aft limit cg. On take off nose pitched up and was hardly held with full forward stick and trim. Increasing speed regained enough elevator power to overcome pitching up. But reflect on this as it might save your skin someday.
He had enough strength to hold stick forward to the stop. Then he should have wound on nose UP trim providing him with increased elevator.
