Throttle for speed, or stick for speed?
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Reading this post thread, I've begun to wonder how it is that gliders actually fly. Seems impossible, them having no power and all.
This thread suggests - once again - that the best way to train a pilot is to start him or her in gliders. Only when the basic aeronautic principles have become ingrained though practical experience in sailplanes is it likely that a pilot is truly ready to 'move on' to powered flight (inverted commas because I appreciate that powered flying is not really a step forward, it's just different).
MLS
P.S. to anyone who may be offended by the above: please note that I said "the best way to train a pilot is to start him or her in gliders", not "the best pilots invariably learned to fly in gliders". It is not my intention to denigrate anyone's background or skills. It is quite possible to become an extremely proficient and knowledgeable pilot without having any gliding experience, although that is not the most efficient way.
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I looked up the word "ukase", which I had supposed was a typographical error in the Collins' book. I was wrong (hardly the first time!). The Merriam-Webster Online Dictionary defines ukase as: "a proclamation by a Russian emperor or government having the force of law; edict".
That sounds about right, regarding theory imposed by the FAA!
That sounds about right, regarding theory imposed by the FAA!
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MLS,
If you're going to quote me, quote the whole sentence, and in context.
And yes, I first learnt to fly in gliders. And I would use the appropriate technique for gliders if in one, or if having to glide a powered aircraft (as I stated in my post!)
But I'm not in a glider! I'm on an approach angle less than the glide angle, so I need a combination of power and attitude to maintain it, and teach the simplest way of achieving that. "Muddling through" isn't good enough, so there is a point to the discussion.
Both of your quoted examples refer to handling in the stall regime which require different techniques. That's why they are taught separately and differently as non-normal situations.
As for you claiming I only have 0.1% the airmanship of Langewiesche senior - well, for one thing we're talking handling/instructional technique, not airmanship as I understand it, and for another sinking to personal slights merely undermines your argument.
But as you state, at least the FAA appears to agree with me!
Miserlou,
Your comments refer to the extreme condition of the approaching stall, for which see above.
If you're going to quote me, quote the whole sentence, and in context.
And yes, I first learnt to fly in gliders. And I would use the appropriate technique for gliders if in one, or if having to glide a powered aircraft (as I stated in my post!)
But I'm not in a glider! I'm on an approach angle less than the glide angle, so I need a combination of power and attitude to maintain it, and teach the simplest way of achieving that. "Muddling through" isn't good enough, so there is a point to the discussion.
Both of your quoted examples refer to handling in the stall regime which require different techniques. That's why they are taught separately and differently as non-normal situations.
As for you claiming I only have 0.1% the airmanship of Langewiesche senior - well, for one thing we're talking handling/instructional technique, not airmanship as I understand it, and for another sinking to personal slights merely undermines your argument.
But as you state, at least the FAA appears to agree with me!
Miserlou,
Your comments refer to the extreme condition of the approaching stall, for which see above.
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Hot damn, I have stirred up a hornets nest here! I thought this was just an innocent query!
Well it has been a very informative thread. Now I've actually finsihed reading the Thom IMC book, I can make a start on "Stick and Rudder".
Well it has been a very informative thread. Now I've actually finsihed reading the Thom IMC book, I can make a start on "Stick and Rudder".
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I think the discussion is getting too complicated. I think the basic point is that by teaching stick-speed gas-height the student learns three very important things: 1)The importance of trim, 2) What the attitude does to speed and 3) What the speed does to height.
Once you have grasped this, to me, it does not matter in what order for for what reason you use a specific control, but in your head it is still stick-speed gas-height. When you are on your glideslope and you push the nose down to change the height to stay on the glideslope, in your head you are thinking stick-speed. Because of this you are watching to correct an increase in speed with the throttle, when you reduce throttle to correct the rising speed you know to anticipate more back pressure and to re-trim. Therefore to me, nothing has changed because
how you deal with a specific situation is really down to the specific situation but the rules are unchanged; stick-speed throttle-height...trim trim trim
Once you have grasped this, to me, it does not matter in what order for for what reason you use a specific control, but in your head it is still stick-speed gas-height. When you are on your glideslope and you push the nose down to change the height to stay on the glideslope, in your head you are thinking stick-speed. Because of this you are watching to correct an increase in speed with the throttle, when you reduce throttle to correct the rising speed you know to anticipate more back pressure and to re-trim. Therefore to me, nothing has changed because
how you deal with a specific situation is really down to the specific situation but the rules are unchanged; stick-speed throttle-height...trim trim trim
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Drifter wrote:
I agree with that completely, (apart from thinking stick-speed: I think stick-rate of descent and then expect speed to increase as a secondary effect )but your words actually describe perfectly the stick-glidepath, power-speed technique!
I agree it doesn't matter what your thought process is but how you handle the aircraft. My point is: to teach flying the approach, it is easier to understand, and is reinforced by S+L techniques, to consider stick-glidepath, power-speed.
Since time immemorial the 'piece of string' idea has been taught. ie If you move the stick forward, the imaginary piece of string through your sleeves requires you to pull the stick back, and vice versa. If low and slow this works, the other technique doesn't.
If I sat next to someone who at 300' on the approach was 5kts below threshold speed and 100 feet low and they pushed the stick forward I would be inclined to take control off them!
When you are on your glideslope and you push the nose down to change the height to stay on the glideslope, in your head you are thinking stick-speed. Because of this you are watching to correct an increase in speed with the throttle, when you reduce throttle to correct the rising speed you know to anticipate more back pressure and to re-trim.
I agree it doesn't matter what your thought process is but how you handle the aircraft. My point is: to teach flying the approach, it is easier to understand, and is reinforced by S+L techniques, to consider stick-glidepath, power-speed.
Since time immemorial the 'piece of string' idea has been taught. ie If you move the stick forward, the imaginary piece of string through your sleeves requires you to pull the stick back, and vice versa. If low and slow this works, the other technique doesn't.
If I sat next to someone who at 300' on the approach was 5kts below threshold speed and 100 feet low and they pushed the stick forward I would be inclined to take control off them!
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Since time immemorial the 'piece of string' idea has been taught. ie If you move the stick forward, the imaginary piece of string through your sleeves requires you to pull the stick back, and vice versa.
So, it appears that we come down to this. There are two paths for the student pilot to follow:
(1) read, absorb, understand and apply the fundamental principles lucidly explained in Stick and Rudder; or
(2) attempt to master 'helpful' memory aids that are based upon "imaginary strings" and similar artificial concepts.
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It's all very well to sneer at people using 'artificial concepts,' but as anyone who's ever taught flying will know, sometimes they are the only way to communicate what you are trying to get across.
My definition of a 'good' student, is not somebody who does exactly what I say, but someone who can make sense of the gobble-de-gook and nonsense that is coming out of my mouth and does what I am thinking.
Not everybody is able to look at dry facts and understand them just like that. I have an engineering degree and an ATPL and I still use some of the silly rhymes and 'artifical concepts' for my own understanding, let alone what I'm trying to put across successfully.
To me the secret of instructing is taking a concept a student is familiar with (driving for instance) and then drawing parallels. Basically going from an area that the student already understands and just extending that knowledge rather than trying to batter in complex concepts straight from the off.
Some people find this unnecessary, but most need something like this or you'll just get the standard smile and nodding head answer when you ask if they understand something complete with glazed eyes.
Anyway, back to the point in hand. On the ILS, speed control with power, stick for rate of descent, bearing in mind that the two are inexorably linked. Oh and get the damn thing trimmed out for the speed you want, it'll make your life a whole lot easier. Get out and practise, it's the only way to get better!
My definition of a 'good' student, is not somebody who does exactly what I say, but someone who can make sense of the gobble-de-gook and nonsense that is coming out of my mouth and does what I am thinking.
Not everybody is able to look at dry facts and understand them just like that. I have an engineering degree and an ATPL and I still use some of the silly rhymes and 'artifical concepts' for my own understanding, let alone what I'm trying to put across successfully.
To me the secret of instructing is taking a concept a student is familiar with (driving for instance) and then drawing parallels. Basically going from an area that the student already understands and just extending that knowledge rather than trying to batter in complex concepts straight from the off.
Some people find this unnecessary, but most need something like this or you'll just get the standard smile and nodding head answer when you ask if they understand something complete with glazed eyes.
Anyway, back to the point in hand. On the ILS, speed control with power, stick for rate of descent, bearing in mind that the two are inexorably linked. Oh and get the damn thing trimmed out for the speed you want, it'll make your life a whole lot easier. Get out and practise, it's the only way to get better!
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I think this thread is confusing.....
The normal sequence of events (that I use) for flying an ILS is:
at the final approach fix, gear down, 1 stage of flap, set power, pitch and trim. Don't touch power again if I can help it. I'm aiming for 100kts, becasue 100kts will give me a particular time to the missed approach point. Too fast and I'll fly past it and possibly into a mountain, to slow then I may not get in when I could have done.
IF my trimming is a bit dodgey and I am a little low, my airspeed should be above 100 kts, so a bit of back pressure on the elevator will bring me back to the glide path and also slow me down. Now I'm established again, I re trim and get it right this time. I haven't touhed power either, and I'm comming down the GS just how I want to.
A little bit high, and a bit of forward elevator will bring me back to the GS and also increase my speed, which should be below 100 kts becasue I know that at this power setting in this configuration I'll get 100 kts out of her descending on the GS.
*Small* power adjustments can be made to take into account wind, after all my guestimations are based on Ground Speed and and not airspeed. Also I might by flying into somewhere like Van Nuys which has a steeper GS, which I have to take account of and obviously the same power setting and I'll be going too fast.
If you keep messing with the throttle when flying an ILS you will generate a nice Sine curve. Try it on a Sim and analyse your descent later on and you'll see what I mean
Cheers
The normal sequence of events (that I use) for flying an ILS is:
at the final approach fix, gear down, 1 stage of flap, set power, pitch and trim. Don't touch power again if I can help it. I'm aiming for 100kts, becasue 100kts will give me a particular time to the missed approach point. Too fast and I'll fly past it and possibly into a mountain, to slow then I may not get in when I could have done.
IF my trimming is a bit dodgey and I am a little low, my airspeed should be above 100 kts, so a bit of back pressure on the elevator will bring me back to the glide path and also slow me down. Now I'm established again, I re trim and get it right this time. I haven't touhed power either, and I'm comming down the GS just how I want to.
A little bit high, and a bit of forward elevator will bring me back to the GS and also increase my speed, which should be below 100 kts becasue I know that at this power setting in this configuration I'll get 100 kts out of her descending on the GS.
*Small* power adjustments can be made to take into account wind, after all my guestimations are based on Ground Speed and and not airspeed. Also I might by flying into somewhere like Van Nuys which has a steeper GS, which I have to take account of and obviously the same power setting and I'll be going too fast.
If you keep messing with the throttle when flying an ILS you will generate a nice Sine curve. Try it on a Sim and analyse your descent later on and you'll see what I mean
Cheers
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Englishal,
Some-one wrote don't fiddle with the power with which I agree-but it will require adjustment.
However, this is the only parameter which is going to need changing as you descend. Without going into density alltitudes, the wind is going to change strength and direction.
Once the aircraft is configured for landing and trimmed to the correct speed then all that remains is to find the correct power setting. You can fly down the glideslope with tiny adjustments of the stick but as soon as you have to maintain any force then you need to adjust the power. The speed range is -0/+10kts.
Some-one wrote don't fiddle with the power with which I agree-but it will require adjustment.
However, this is the only parameter which is going to need changing as you descend. Without going into density alltitudes, the wind is going to change strength and direction.
Once the aircraft is configured for landing and trimmed to the correct speed then all that remains is to find the correct power setting. You can fly down the glideslope with tiny adjustments of the stick but as soon as you have to maintain any force then you need to adjust the power. The speed range is -0/+10kts.
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It's all very well to sneer at people using 'artificial concepts,' but as anyone who's ever taught flying will know, sometimes they are the only way to communicate what you are trying to get across.
Imagine a piece of string tied to the bottom of the steering wheel with the other end tied to the throttle. As you turn the wheel the throttle comes up and you press the throttle the steering wheel straightens. The basic principle is that the car can only do 100% and everything is a proportion of it. I thought it was a supurb way of explaining it and it has stuck ever since. But like all the models it isn't rote, but really helps form an understanding of what generally works.
Just in case anybody is interested: http://www.amazon.co.uk/exec/obidos/...267851-7967013
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On a 3 degree glideslope rate of descent is groundspeed x 5.
100 knots groundspeed is 500ft per min.
Go fly around in practice area and find the power setting which gives you that rate of descent in that plane in the configuration you want to fly the ILS.
Set power setting at that level, intercept glideslope, if you need to then modify power to find rate of descent which will keep you on glideslope when miles out and needle not sensitive. Leave power there unless you have no choice.
Trim it up, use trim to maintain glideslope. Small adjustments, trim, trim, trim.
Don't f**k with anything until you have crossed the threshold, runways with ILS on the end of them are long and you won't run off the end (usually!)
This thread has confused the hell out of me!
100 knots groundspeed is 500ft per min.
Go fly around in practice area and find the power setting which gives you that rate of descent in that plane in the configuration you want to fly the ILS.
Set power setting at that level, intercept glideslope, if you need to then modify power to find rate of descent which will keep you on glideslope when miles out and needle not sensitive. Leave power there unless you have no choice.
Trim it up, use trim to maintain glideslope. Small adjustments, trim, trim, trim.
Don't f**k with anything until you have crossed the threshold, runways with ILS on the end of them are long and you won't run off the end (usually!)
This thread has confused the hell out of me!
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slim wrote:
Slim, can you tell me what aircraft type you fly an ILS like this on, and whether this was a technique you were taught for IF or whether it's a 'top tip' given by a fellow aviator.
Does it mean that if, say, you are drifting low on the glidepath you just make small pitch up trim inputs until back on the glidepath and then small pitch down trim inputs to maintain it?
I'm just curious as it's not something I've heard of before.
Trim it up, use trim to maintain glideslope. Small adjustments, trim, trim, trim.
Does it mean that if, say, you are drifting low on the glidepath you just make small pitch up trim inputs until back on the glidepath and then small pitch down trim inputs to maintain it?
I'm just curious as it's not something I've heard of before.
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It's all very well to sneer at people using 'artificial concepts,' but as anyone who's ever taught flying will know, sometimes they are the only way to communicate what you are trying to get across.
But - at the risk of repeating myself - all necessary information on the question posed at the start of this thread is spelt out, in crystal clear language and simple diagrams, without any fancy mathematical theory, in Stick and Rudder. Any student who can't understand that book would seem unsafe to be put in sole charge of an ice cream cone, let alone an aircraft.
I don't mean to insult anyone who has contributed to this thread. My point is simply that Langewiesche got it right the first time, so what's the point in re-inventing the wheel, particularly in a questionable manner?
If someone believes that Stick and Rudder is unreliable, please say so, and explain why you are of that opinion. I'm certainly willing to reconsider my faith in the book, if anyone has plausible criticisms to offer.
Thanks!
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Slim,
I too would like to know where this 'trim, trim, trim' bull(expletive deleted) comes from.
It really is one of the most ill-advised pieces of advice I've ever come across. If one has too little power applied and keeps trimming up you're going to stall eventually.
The required rate of descent to fly down the glidepath, whatever the angle, will vary according to the wind and there are plenty of conditions which will cause this to change, sea breezes, inversions, friction, coriolis, et al.
Power is the only variable.
MLS, 'Stick and Rudder' didn't get to be the classic it is by being factually incorrect.
I too would like to know where this 'trim, trim, trim' bull(expletive deleted) comes from.
It really is one of the most ill-advised pieces of advice I've ever come across. If one has too little power applied and keeps trimming up you're going to stall eventually.
The required rate of descent to fly down the glidepath, whatever the angle, will vary according to the wind and there are plenty of conditions which will cause this to change, sea breezes, inversions, friction, coriolis, et al.
Power is the only variable.
MLS, 'Stick and Rudder' didn't get to be the classic it is by being factually incorrect.
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Alright, here's the nice simple way to fly an ILS. That I've used about 700 times in the last 12 months.
1) Establish on the localiser at the lower step Height/Alt/whatever you've been cleared to establish at.
2) Start bringing the speed back whilst level, depending on the speed you are going to use on the approach, this can be gear limiting speed down to slightly above the approach speed. Get it trimmed.
3) One dot fly-up indication. Gear down.
4) Half a dot high, props to max, approach flap down. Trim it again. This should bring you down from your slightly higher speed, back to the approach speed you are using.
5) On the glide, bring power back to a nominated (lowish) setting. Down you go. If it's trimmed correctly you shouldn't have to do much.
6) Maintain the LOC and G/S with small corrections. Remember as you descend the wind often changes both in direction and strength. Also as you get closer to the field it all gets more sensitive. Halve any correction you are going to make. If you notice a trend away, stop it initially, then re-establish, don't try to do too much at once and certainly don't fiddle constantly with the trim.
Having said that however, as a very wise old pilot once said to me, Trim in VFR flying is important, in IFR it is essential.
Make all corrections small ones and if it all goes up the spout, go around and try again. It's happened to all of us at one time or another. I remember a controller at a certain large airfield offering to lose the tapes on one approach I made once. Ahem....
Getting bogged down in the semantics of point and power Vs. anything else is a waste of time, since there isn't really two different ways of doing it. Watch someone who knows what they are doing and they'll be manipulating the attitude and power at the same time without even thinking about it.
At the end of the day the aim is to get safely onto the ground, the minutae of how you got there is irrelevant.
What works for you?
7) get visual, stick it on the numbers. Go get a cup of tea.
As for the comment about only some topics needing idiots guides, not true at all. Every student is different, some find Nav difficult, others engine theory or aerodynamics. I personally have different explanations for virtually every topic we cover and at some time or other I've had to use all of them. I'm still trying to think of more since there are somethings I don't think I explain in easy enough terms.
The attitude that says untechnically minded people shouldn't be allowed near aircraft is rubbish. There are many things that 'convention' says we should understand otherwise we aren't safe. Again nonsense. Knowing exactly how some highly technical piece of kit works isn't the most important thing. Knowing how to cope if it fails or what the signs are of it's imminent failure is far more important than what some random widget does.
Flying is sometimes so far up it's own backside it's untrue, these barriers to entry are usually perpetuated by people who aren't exactly ace of the base themselves. Have a look in any flying club and the person holding court is usually the biggest muppet there. As you can probably tell, it's one of my pet hates!!
1) Establish on the localiser at the lower step Height/Alt/whatever you've been cleared to establish at.
2) Start bringing the speed back whilst level, depending on the speed you are going to use on the approach, this can be gear limiting speed down to slightly above the approach speed. Get it trimmed.
3) One dot fly-up indication. Gear down.
4) Half a dot high, props to max, approach flap down. Trim it again. This should bring you down from your slightly higher speed, back to the approach speed you are using.
5) On the glide, bring power back to a nominated (lowish) setting. Down you go. If it's trimmed correctly you shouldn't have to do much.
6) Maintain the LOC and G/S with small corrections. Remember as you descend the wind often changes both in direction and strength. Also as you get closer to the field it all gets more sensitive. Halve any correction you are going to make. If you notice a trend away, stop it initially, then re-establish, don't try to do too much at once and certainly don't fiddle constantly with the trim.
Having said that however, as a very wise old pilot once said to me, Trim in VFR flying is important, in IFR it is essential.
Make all corrections small ones and if it all goes up the spout, go around and try again. It's happened to all of us at one time or another. I remember a controller at a certain large airfield offering to lose the tapes on one approach I made once. Ahem....
Getting bogged down in the semantics of point and power Vs. anything else is a waste of time, since there isn't really two different ways of doing it. Watch someone who knows what they are doing and they'll be manipulating the attitude and power at the same time without even thinking about it.
At the end of the day the aim is to get safely onto the ground, the minutae of how you got there is irrelevant.
What works for you?
7) get visual, stick it on the numbers. Go get a cup of tea.
As for the comment about only some topics needing idiots guides, not true at all. Every student is different, some find Nav difficult, others engine theory or aerodynamics. I personally have different explanations for virtually every topic we cover and at some time or other I've had to use all of them. I'm still trying to think of more since there are somethings I don't think I explain in easy enough terms.
The attitude that says untechnically minded people shouldn't be allowed near aircraft is rubbish. There are many things that 'convention' says we should understand otherwise we aren't safe. Again nonsense. Knowing exactly how some highly technical piece of kit works isn't the most important thing. Knowing how to cope if it fails or what the signs are of it's imminent failure is far more important than what some random widget does.
Flying is sometimes so far up it's own backside it's untrue, these barriers to entry are usually perpetuated by people who aren't exactly ace of the base themselves. Have a look in any flying club and the person holding court is usually the biggest muppet there. As you can probably tell, it's one of my pet hates!!
Last edited by Say again s l o w l y; 17th Feb 2005 at 22:47.
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Miserlou, MLS-12D,
Reading this post thread, I've begun to wonder how it is that gliders actually fly. Seems impossible, them having no power and all
Well gliders can't "fly" they can only glide. A glider flying at a constant airspeed can not maintain level flight and it can not climb...........all it can do is glide - descend - convert potential energy.
Perhaps I should repeat a statement I made earlier - If one makes a glide approach at say 70Kt and next time one wants to make a more shallow approach but also at 70Kt - one will have to use power to maintain the airspeed at 70Kt..........similarly if one is descending with power at 70Kt and one wants to make the approach angle more shallow for whatever reason - one will have to increase power to maintain 70Kt on this more shallow approach...........if one wants to make a steeper approach at 70Kt, one will have to reduce the power to avoid having a higher speed.
Now tell me that the reason why we are maintaining 70Kt is because I am moving the stick?
Regards,
DFC
Reading this post thread, I've begun to wonder how it is that gliders actually fly. Seems impossible, them having no power and all
Well gliders can't "fly" they can only glide. A glider flying at a constant airspeed can not maintain level flight and it can not climb...........all it can do is glide - descend - convert potential energy.
Perhaps I should repeat a statement I made earlier - If one makes a glide approach at say 70Kt and next time one wants to make a more shallow approach but also at 70Kt - one will have to use power to maintain the airspeed at 70Kt..........similarly if one is descending with power at 70Kt and one wants to make the approach angle more shallow for whatever reason - one will have to increase power to maintain 70Kt on this more shallow approach...........if one wants to make a steeper approach at 70Kt, one will have to reduce the power to avoid having a higher speed.
Now tell me that the reason why we are maintaining 70Kt is because I am moving the stick?
Regards,
DFC
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No. If you move the stick, you'll change the speed.
If the aircraft is trimmed properly, then by slowly adding and reducing power, the a/c should climb and descend whilst maintaining roughly the same speed. Big changes in pwer setting will have an unsettling effect and the speed may change dramatically.
A glider can only maintain a constant airspeed and constant alt if in an updraught, basically the vertical movement of air is adding energy into the system. What we power pilots do by burning some fuel.
DFC, I do know it's a rhetorical question, but I couldn't help myself!
If the aircraft is trimmed properly, then by slowly adding and reducing power, the a/c should climb and descend whilst maintaining roughly the same speed. Big changes in pwer setting will have an unsettling effect and the speed may change dramatically.
A glider can only maintain a constant airspeed and constant alt if in an updraught, basically the vertical movement of air is adding energy into the system. What we power pilots do by burning some fuel.
DFC, I do know it's a rhetorical question, but I couldn't help myself!