Throttle for speed, or stick for speed?
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That's very interesting Whopity.
Why do the laws of aerodynamics change when you bank then?
I'd rather understood that if you have a constant bank angle, pitch attitude and speed but found yourself descending, you needed more power. If you already have full power then there is only one option left...lower the nose a little.
Why do the laws of aerodynamics change when you bank then?
I'd rather understood that if you have a constant bank angle, pitch attitude and speed but found yourself descending, you needed more power. If you already have full power then there is only one option left...lower the nose a little.
Miserlou,
they don't.
Whatever you do, Attitude + Power = Performance; if you change either attitude or power you will need to change the other inversely to maintain the performance. Which you do first, is a matter of choice however, instrument lag and aircraft inertia may determine that one way is more effective than the other in certain circumstances.
When climbing and descening at a fixed power then attitude is the only way to control airspeed, which of course should always be trimmed, if you instructor tells you otherwise change him for a better one.
The object on an approach is to fly a line of constant bearing from the point where you roll out on final to the touchdown point. Personally, I find it much easier to hold that bearing optically than fishing arround with the attitude and descending in a series of steps. If the attitude and power remain constant only the met will change things.
they don't.
Whatever you do, Attitude + Power = Performance; if you change either attitude or power you will need to change the other inversely to maintain the performance. Which you do first, is a matter of choice however, instrument lag and aircraft inertia may determine that one way is more effective than the other in certain circumstances.
When climbing and descening at a fixed power then attitude is the only way to control airspeed, which of course should always be trimmed, if you instructor tells you otherwise change him for a better one.
The object on an approach is to fly a line of constant bearing from the point where you roll out on final to the touchdown point. Personally, I find it much easier to hold that bearing optically than fishing arround with the attitude and descending in a series of steps. If the attitude and power remain constant only the met will change things.
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Greeners describes the way I was taught, and it works for me. "Use the force"! I don't really think about it in VFR - just look at the spot on the runway where I want to crash, and the aeroplane goes there.
For IFR, I had an outstanding instructor, and he taught me to fly "by the numbers". I know, for my aircraft, the power settings that will achieve S&L and the normal ROC and ROD. Set those, trim (trim) and the aeroplane does what you want. For minor adjustments, it's usually the yoke for me - the power stays in the right place.
I suppose it would be very different in an aircraft with widely varying weights, but with the standard load in the Arrow, that works fine.
For IFR, I had an outstanding instructor, and he taught me to fly "by the numbers". I know, for my aircraft, the power settings that will achieve S&L and the normal ROC and ROD. Set those, trim (trim) and the aeroplane does what you want. For minor adjustments, it's usually the yoke for me - the power stays in the right place.
I suppose it would be very different in an aircraft with widely varying weights, but with the standard load in the Arrow, that works fine.
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keef,
For minor adjustments, it's usually the yoke for me - the power stays in the right place.
Yes, fly the numbers, but for small adjustments (like what you should be doing on an ILS) have you tried just making very small adjustments to your pitch using the trim wheel to stay on the glideslope? That's small adjustments by the way. Its actually a lot easier and more sensitive than using the yoke. Did I mention only using this technique for small adjustments to pitch?
Use the rudder for small adjustments when flying the localiser. Apparently this heretic approach also works nicely on bigger turbine powered stuff, but that's only what I've been told by others
For minor adjustments, it's usually the yoke for me - the power stays in the right place.
Yes, fly the numbers, but for small adjustments (like what you should be doing on an ILS) have you tried just making very small adjustments to your pitch using the trim wheel to stay on the glideslope? That's small adjustments by the way. Its actually a lot easier and more sensitive than using the yoke. Did I mention only using this technique for small adjustments to pitch?
Use the rudder for small adjustments when flying the localiser. Apparently this heretic approach also works nicely on bigger turbine powered stuff, but that's only what I've been told by others
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Algirdas,
You could (and would) but maintaining the bank angle proves that Whopity's explanation is false.. Therefore, bank angle-constant, power-constant, speed constant. The only thing left to control the speed, which would be reducing if you maintain altitude, is adjust the attitude.
Whopity,
Attitude+power=performance is an old cliche. Please supply us with the correct mathematical equation showing the inverse proportionality.
In your wriggling you've just just introduced a fixed power setting where no fixed power setting belongs. The required constants for an approach are airspeed and flightpath. Manifold pressure or torque will change due to atmospherics and the required power because of the wind. You can maintain the glidepath with the stick, just as you would a constant height, but I reckon any more than a needle-width, as I said earlier, is more likely a trend or change in conditions requiring a power change.
If you want to discuss which one should do first then we'll have to come right back to perhaps one knot above the stall and apply full power, whilst holding everything else constant (and at a safe height). It's a good technique to get a clean entry into a spin or flick!
You could (and would) but maintaining the bank angle proves that Whopity's explanation is false.. Therefore, bank angle-constant, power-constant, speed constant. The only thing left to control the speed, which would be reducing if you maintain altitude, is adjust the attitude.
Whopity,
Attitude+power=performance is an old cliche. Please supply us with the correct mathematical equation showing the inverse proportionality.
In your wriggling you've just just introduced a fixed power setting where no fixed power setting belongs. The required constants for an approach are airspeed and flightpath. Manifold pressure or torque will change due to atmospherics and the required power because of the wind. You can maintain the glidepath with the stick, just as you would a constant height, but I reckon any more than a needle-width, as I said earlier, is more likely a trend or change in conditions requiring a power change.
If you want to discuss which one should do first then we'll have to come right back to perhaps one knot above the stall and apply full power, whilst holding everything else constant (and at a safe height). It's a good technique to get a clean entry into a spin or flick!
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If you want to discuss which one should do first then we'll have to come right back to perhaps one knot above the stall and apply full power, whilst holding everything else constant (and at a safe height). It's a good technique to get a clean entry into a spin or flick!
One can certainly understand the differences that may be required to handle heavies, or even just jets, given their mass and the spool up time etc however it seems there is no clear picture even for SEP GA.
1) Operating at or close to the bottom of the drag curve, it's not possible to make sustained corrections reliably with pitch. Whether you pull or push, your glideslope gets steeper. As you move away from the bottom of the drag curve, the trade off between speed between glideslope changes gearing. A substantial change in glideslope adjusted by pitch causes only a small speed variation.
2) At the same time, as speed increases, the phugoid period increases in proportion. When you add thrust at a constant AOA, the primary effect of the thrust increase is a speed increase -- equilibrium isn't instant, and it takes some time for that speed increase to get turned into a change in glideslope at the original speed. The time required for it to "sort itself out" is proportional to the phugoid period.
3) Faster aircraft tend to be powered by more complex powerplants. While the turbine with a substantial spool time is an extreme, turbocharging and even constant speed units cause short delays between throttle movement and response. That makes it harder to make fine adjustments with power.
All of those make this game horses-for-courses.
The technique that works best at visual approach speeds in a C152 and the technique that works best for a turbo-charged Bonanza flying an ILS approach may well be different.
FWIW, the best mnemonic I even learned for the ILS was DFWTP: Don't ...er... Fiddle With The Power.
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Think about it in energy terms.
If you are slow or below the glidepath or both, you need to ADD energy, ie add power and/or raise the nose attitude. Even in jets, the approach power is set to give sufficient responsiveness to power changes, so in the first instance I would always adjust power if slow.
Would those advocating the stick for speed method push the stick forward if low and slow? Of course not, so why confuse a student with that technique?
Use the same technique you would use S+L, why change it?
As for slim slag's idea of rudder to maintain the localiser, you'd fail an IRT for using that technique for several reasons: Associated roll, discomfort for pax, Flight Director problems, destabilising drag increase.....
If you are slow or below the glidepath or both, you need to ADD energy, ie add power and/or raise the nose attitude. Even in jets, the approach power is set to give sufficient responsiveness to power changes, so in the first instance I would always adjust power if slow.
Would those advocating the stick for speed method push the stick forward if low and slow? Of course not, so why confuse a student with that technique?
Use the same technique you would use S+L, why change it?
As for slim slag's idea of rudder to maintain the localiser, you'd fail an IRT for using that technique for several reasons: Associated roll, discomfort for pax, Flight Director problems, destabilising drag increase.....
Last edited by Classic; 15th Feb 2005 at 19:56.
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Atitude + Power = Performance.
Pitch up - speed decreases - lift decreases
Pitch down - speed increases - lift increases
Increase power - speed increases - lift increases - aircraft pitch moments change
Decrease power - speed decreases - lift decreases - aircraft pitch moments change
Everything is interlinked.
Point the aircraft where you want to go (attitude) and adjust the power to give the required speed (power) can provide very stable approaches thus making it easy to determine "impact point".
Making an approach that will hit the numbers can be done as a constant speed but a number of different power settings -
No power - a glide approach - this is the steepest approach you can do without gaining further speed above the chosen speed (ignoring side-slip etc)
Full power - this is where you hit the numbers in the climb from below (theoretical only)
Just less than cruise power (for that speed) - where the approach path is almost level. Nice for that carrier landing!
Taking the extremes -
If the glide approach is putting you long (beyond the numbers) you have no choice but to accept that if you lower the nose - the speed will increase and you will hit the numbers but for a real approach you have to wash off that extra speed.
If the (theroetical) full power climb is going to reach the level of the imaginary runway beyond the numbers - you have no choice but to accept that because raising the nose further will reduce the speed below the chosen speed.
So each approach will depending on how steep the desired approach path is, have an aiming point and a power setting.
Moving the aiming point will have an effect on the speed - changing the speed vector will simply get you to the aiming point faster.
Drag slows us down and works to oppose our efforts at travelling towards our aiming point - the force that prevents us slowing down is thrust.
If you want to make an approach at say 70Kt to a particular aiming point - you have two choices - make a glide approach at 70Kt or use power to maintain 70Kt while making a less steep approach..........the point where the aircraft will hit the runway has not changed and the aircraft is still travelling towards it - but to prevent the aircraft from slowing down on the more shallow approach power is used to maintain the speed.
How one pictures it makes litle difference - It is the total pefromance (Attitude + Power) that counts.
To see this for oneself - try the following flying with a trusted fellow pilot:
Set the aircraft up on a 3deg power approach in the desired configuration and speed and on the glideslope according to ILS or PAPI. Take a marker and mark the windscreen where the touchdown point (abeam the PAPI) is on the window.
Now take the aircraft round again and try various approaches above and below the 3deg but always aiming for that same point (abeam the PAPI). You keep that mark fixed on the aiming point using the stick and get your friend to use the throttle to maintain the speed. See how it works.
Next position the aircraft below the glide and again with your friend using the throttle to maintain speed - move the aim point up towards the horizon and hold it there until established on the 3 deg slope then lower it to the runway aim point. Then do the same from above by putting the aim point before the threshold (all while your friend uses power to maintain speed).
You will find that if you let things get too high, your friend will have the throttle closed because you have the aircraft in the glide attitude - any steeper and you have to accept a higher speed!
Don't try the flying it almost level with high power to the runway in this life!
Hope the above ramblings help!
Regards,
DFC
Pitch up - speed decreases - lift decreases
Pitch down - speed increases - lift increases
Increase power - speed increases - lift increases - aircraft pitch moments change
Decrease power - speed decreases - lift decreases - aircraft pitch moments change
Everything is interlinked.
Point the aircraft where you want to go (attitude) and adjust the power to give the required speed (power) can provide very stable approaches thus making it easy to determine "impact point".
Making an approach that will hit the numbers can be done as a constant speed but a number of different power settings -
No power - a glide approach - this is the steepest approach you can do without gaining further speed above the chosen speed (ignoring side-slip etc)
Full power - this is where you hit the numbers in the climb from below (theoretical only)
Just less than cruise power (for that speed) - where the approach path is almost level. Nice for that carrier landing!
Taking the extremes -
If the glide approach is putting you long (beyond the numbers) you have no choice but to accept that if you lower the nose - the speed will increase and you will hit the numbers but for a real approach you have to wash off that extra speed.
If the (theroetical) full power climb is going to reach the level of the imaginary runway beyond the numbers - you have no choice but to accept that because raising the nose further will reduce the speed below the chosen speed.
So each approach will depending on how steep the desired approach path is, have an aiming point and a power setting.
Moving the aiming point will have an effect on the speed - changing the speed vector will simply get you to the aiming point faster.
Drag slows us down and works to oppose our efforts at travelling towards our aiming point - the force that prevents us slowing down is thrust.
If you want to make an approach at say 70Kt to a particular aiming point - you have two choices - make a glide approach at 70Kt or use power to maintain 70Kt while making a less steep approach..........the point where the aircraft will hit the runway has not changed and the aircraft is still travelling towards it - but to prevent the aircraft from slowing down on the more shallow approach power is used to maintain the speed.
How one pictures it makes litle difference - It is the total pefromance (Attitude + Power) that counts.
To see this for oneself - try the following flying with a trusted fellow pilot:
Set the aircraft up on a 3deg power approach in the desired configuration and speed and on the glideslope according to ILS or PAPI. Take a marker and mark the windscreen where the touchdown point (abeam the PAPI) is on the window.
Now take the aircraft round again and try various approaches above and below the 3deg but always aiming for that same point (abeam the PAPI). You keep that mark fixed on the aiming point using the stick and get your friend to use the throttle to maintain the speed. See how it works.
Next position the aircraft below the glide and again with your friend using the throttle to maintain speed - move the aim point up towards the horizon and hold it there until established on the 3 deg slope then lower it to the runway aim point. Then do the same from above by putting the aim point before the threshold (all while your friend uses power to maintain speed).
You will find that if you let things get too high, your friend will have the throttle closed because you have the aircraft in the glide attitude - any steeper and you have to accept a higher speed!
Don't try the flying it almost level with high power to the runway in this life!
Hope the above ramblings help!
Regards,
DFC
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Classic,
Perhaps I could remind you of the procedure for recovery from the the stall.
1. Release back pressure on controls.
2. Apply power.
So would you push the stick forward if low and slow? Of course you would or maybe you end up in a hospital bed with a previously mentioned glider pilot.
Perhaps I could remind you of the procedure for recovery from the the stall.
1. Release back pressure on controls.
2. Apply power.
So would you push the stick forward if low and slow? Of course you would or maybe you end up in a hospital bed with a previously mentioned glider pilot.
Grandpa Aerotart
One very important part of this discussion that seems missing so far is this.
The thottle = speed dictum is related mostly to jets...particularly heavy jets. This is because they have such relatively high weight and therefore momentum that if you're slow and lower the nose you will just get a huge increase in ROD...long before you get any meaningfull increase in speed. It's fairly similar in very heavy prop aeroplanes too...but mostly jets...with prop aeroplanes, particularly big multi engined ones an increase in power brings about an increase in lift from the accelerated air travelling over the wings and then some acceleration....pour on the coals in a jet and the lift only increases as a buy product of the extra speed....jets are usually approaching to land on the back side of the drag curve which just exacerbates the effect...prop aircraft, particularly little ones are not...to anywhere near the same extent anyway.
So in a jet we trim for a specific attitude and hold speed constant with thrust....a little slow=more thrust...a little fast = less thrust...a little high = lower the nose...a little low = raise it. The very high momentum means that raising or lowering the nose has little effect on speed in the short term. In a jet if I am a little low and increase thrust I'll just go lower faster because I don't have the instant increase in lift you get from increasing power in a typical GA twin/single.
So many techniques filter down to GA from Airlines and are assumed to be better simply because that's the way the big boys do it.
That is just plane wrong...I don't fly my Bonanza the same way I fly the 767 I earn a living in...they are very different aircraft and require a slighty different technique.
In a light aircraft Power and Attitude = Performance....so too in a heavy jet....just the technique used to arrive at the required performance varies slightly.
The thottle = speed dictum is related mostly to jets...particularly heavy jets. This is because they have such relatively high weight and therefore momentum that if you're slow and lower the nose you will just get a huge increase in ROD...long before you get any meaningfull increase in speed. It's fairly similar in very heavy prop aeroplanes too...but mostly jets...with prop aeroplanes, particularly big multi engined ones an increase in power brings about an increase in lift from the accelerated air travelling over the wings and then some acceleration....pour on the coals in a jet and the lift only increases as a buy product of the extra speed....jets are usually approaching to land on the back side of the drag curve which just exacerbates the effect...prop aircraft, particularly little ones are not...to anywhere near the same extent anyway.
So in a jet we trim for a specific attitude and hold speed constant with thrust....a little slow=more thrust...a little fast = less thrust...a little high = lower the nose...a little low = raise it. The very high momentum means that raising or lowering the nose has little effect on speed in the short term. In a jet if I am a little low and increase thrust I'll just go lower faster because I don't have the instant increase in lift you get from increasing power in a typical GA twin/single.
So many techniques filter down to GA from Airlines and are assumed to be better simply because that's the way the big boys do it.
That is just plane wrong...I don't fly my Bonanza the same way I fly the 767 I earn a living in...they are very different aircraft and require a slighty different technique.
In a light aircraft Power and Attitude = Performance....so too in a heavy jet....just the technique used to arrive at the required performance varies slightly.
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So many techniques filter down to GA from Airlines and are assumed to be better simply because that's the way the big boys do it.
Would those advocating the stick for speed method push the stick forward if low and slow? Of course not, so why confuse a student with that technique?
If "low and slow", one is faced with two distinct problems; IMHO, the proper course is to lower the nose and add power (or close the divebrakes, if flying a sailplane).
See generally "Where Does Airspeed Come From?"
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Yes, of course you're quite correct. Releasing back pressure is usually quite sufficient to avoid a stall ... there is no need to stuff the stick all of the way forward, especially at low altitude.
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Who said anything about being at the stall? If low and slow, raising the nose brings you back to the desired glidepath, and simultaneously adding power brings you to your desired speed (and pitches the nose up to help you and reduces the stall speed in an SEP).
You can argue that by making each input simultaneously you would be advocating the same as the 'stick for speed' argument, by using that technique simultaneously too. My point is, why teach a student this non-intuitive way of flying an approach? If both techniques work (as they obviously must, reading this thread) why teach a different one for flying down a slope than for straight and level? Also you are then telling the student (someone with little feel for the aircraft and often still flying by numbers) to change the technique as they enter the flare - bleed the speed off with the throttle and adjust rate of descent with the stick.
It applies to a light aircraft as it does to a heavy.
And Miserlou, MLS, Slim Slag, if you were low and slow (small increments I'm talking about, not at the stall, different problem and different solution altogether) and you lowered the nose before adding power, you would all be down there with the aforementioned gliderpilot.
As DFC says, it's total performance that counts: attitude + power= desired performance and they need to be considered as 2 simultaneously managed parameters. But to teach that you have to teach one coherent technique in your mind which can work for all phases of flight: power for speed, stick for flightpath. (Excepting glide and full power climb, obviously).
Think about it, it too obviously works, and it's instinctive - ask your teenage kid what he/she thinks you should do if slow in an aeroplane!
Oh, and slim slag,
I should have said just a small amount wrong! 
You can argue that by making each input simultaneously you would be advocating the same as the 'stick for speed' argument, by using that technique simultaneously too. My point is, why teach a student this non-intuitive way of flying an approach? If both techniques work (as they obviously must, reading this thread) why teach a different one for flying down a slope than for straight and level? Also you are then telling the student (someone with little feel for the aircraft and often still flying by numbers) to change the technique as they enter the flare - bleed the speed off with the throttle and adjust rate of descent with the stick.
It applies to a light aircraft as it does to a heavy.
And Miserlou, MLS, Slim Slag, if you were low and slow (small increments I'm talking about, not at the stall, different problem and different solution altogether) and you lowered the nose before adding power, you would all be down there with the aforementioned gliderpilot.
As DFC says, it's total performance that counts: attitude + power= desired performance and they need to be considered as 2 simultaneously managed parameters. But to teach that you have to teach one coherent technique in your mind which can work for all phases of flight: power for speed, stick for flightpath. (Excepting glide and full power climb, obviously).
Think about it, it too obviously works, and it's instinctive - ask your teenage kid what he/she thinks you should do if slow in an aeroplane!
Oh, and slim slag,
small adjustments, classic. small adjustments. If you can feel it you have used too much
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Who said anything about being at the stall?
ask your teenage kid what he/she thinks you should do if slow in an aeroplane!
You know how the controls are labled on an alarm clock or on a kitchen stove. These are arrows marked "on" and "off", "slow" or "fast", "hot" or "cold", telling the customer exactly which way to move what control in order to get what result. Well – here is an idea for one of those unflyable days at the airport; how would you label an airplane’s elevator and throttle?
Your kid brother, knowing what every boy knows about flying, will call this one easy. He will label the throttle “fast” and “slow”. Does not the throttle do to the airplane’s motor exactly what the gas pedal does to an automobile motor? And he will label the stick “up” and “down”. Does not pulling back on the stick make the airplane go up and down? It is only common sense.
Unfortunately, though, the present conventional airplane is not a common-sense contraption; and this labeling of its controls is wrong. It is wrong not only “in theory”; it is wrong also in practice. It is dead wrong; if you really did try to use the controls that way, you would kill yourself. Most fatal airplane crashes happen precisely because the pilot has the controls so labelled in his mind and tries to "elevate" himself, or at least hold himself up, by pulling back desperately on the so-called "elevator". An airplane will not go up, nor will it stay up, simply because the pilot pulls the stick back. In fact, in all the more critical situations of flight, it is all too likely to do exactly the contrary! In the glide, for instance, the farther the stick is held back, the more steeply downward will the flight path be - even though the nose may not point down steeply. In a stall or spin, the ship is dropping precisely just because the stick is held too far back! As for the throttle's being a speed control, the fact is that you can stall with the throttle wide open! Most fatal stall or spin accidents do occur with the engine running nicely at cruising throttle! In fact, when the throttle is open and the propellor blast is hitting the tail, the average airplane actually wants to fly more slowly, and will stall more readily, then with power off! In short, the elevator does not make the airplane go up or down, and the throttle does not make it go fast or slow, and your kid brother is wrong.
Your kid brother, knowing what every boy knows about flying, will call this one easy. He will label the throttle “fast” and “slow”. Does not the throttle do to the airplane’s motor exactly what the gas pedal does to an automobile motor? And he will label the stick “up” and “down”. Does not pulling back on the stick make the airplane go up and down? It is only common sense.
Unfortunately, though, the present conventional airplane is not a common-sense contraption; and this labeling of its controls is wrong. It is wrong not only “in theory”; it is wrong also in practice. It is dead wrong; if you really did try to use the controls that way, you would kill yourself. Most fatal airplane crashes happen precisely because the pilot has the controls so labelled in his mind and tries to "elevate" himself, or at least hold himself up, by pulling back desperately on the so-called "elevator". An airplane will not go up, nor will it stay up, simply because the pilot pulls the stick back. In fact, in all the more critical situations of flight, it is all too likely to do exactly the contrary! In the glide, for instance, the farther the stick is held back, the more steeply downward will the flight path be - even though the nose may not point down steeply. In a stall or spin, the ship is dropping precisely just because the stick is held too far back! As for the throttle's being a speed control, the fact is that you can stall with the throttle wide open! Most fatal stall or spin accidents do occur with the engine running nicely at cruising throttle! In fact, when the throttle is open and the propellor blast is hitting the tail, the average airplane actually wants to fly more slowly, and will stall more readily, then with power off! In short, the elevator does not make the airplane go up or down, and the throttle does not make it go fast or slow, and your kid brother is wrong.
Elevator versus Throttle
As you know, in recent years there has been a lot of discussion about what controls airspeed and what controls altitude. By FAA ukase (sic) we are required to think, or at least to say on our writtens, that the elevator controls altitude and the throttle controls airspeed.
I think this is a horribly dangerous concept when the chips are down, because it can cause pilots to bull back on the stick to go up, or, after an engine failure, to stay up. It is instinctive for people to think in terms of pulling back on the stick to climb or maintain altitude, because it is so logical.
The best example I know of this universal impulse came a few years back. My friend, little Helen Langewiesche, had been given a spin demonstration before soloing a glider. One evening after dinner with Helen and her test-pilot/author, Wolfgang, I asked her what she would do with the stick if ever she found herself nose-down and starting to autoroate. Her answer: "Why dummy, I'd pull the stick back all the way, because if you don't get the nose pointed up instead of down, you're going to fly into the ground". Stick and Rudder, over on the other side of the fireplace, became rigid. I paled. In the ensuing silence, Helen added, "Oh, well, yes, first it is necessary to lower the nose to get some speed, and then you can get headed away from the ground." In short, she knew better, but her initial statement revealed a universal instinct that has to be trained out of people.
A proper concept of airspeed and altitude control is important in thinking about takesoffs and landings, because these are low-altitude operations, and virtually all stall/spin/mush accidents begin close to pattern altitude. And those who, ground-shy, instinctively pull the stick back to gain or maintain altitude, go down.
As you know, in recent years there has been a lot of discussion about what controls airspeed and what controls altitude. By FAA ukase (sic) we are required to think, or at least to say on our writtens, that the elevator controls altitude and the throttle controls airspeed.
I think this is a horribly dangerous concept when the chips are down, because it can cause pilots to bull back on the stick to go up, or, after an engine failure, to stay up. It is instinctive for people to think in terms of pulling back on the stick to climb or maintain altitude, because it is so logical.
The best example I know of this universal impulse came a few years back. My friend, little Helen Langewiesche, had been given a spin demonstration before soloing a glider. One evening after dinner with Helen and her test-pilot/author, Wolfgang, I asked her what she would do with the stick if ever she found herself nose-down and starting to autoroate. Her answer: "Why dummy, I'd pull the stick back all the way, because if you don't get the nose pointed up instead of down, you're going to fly into the ground". Stick and Rudder, over on the other side of the fireplace, became rigid. I paled. In the ensuing silence, Helen added, "Oh, well, yes, first it is necessary to lower the nose to get some speed, and then you can get headed away from the ground." In short, she knew better, but her initial statement revealed a universal instinct that has to be trained out of people.
A proper concept of airspeed and altitude control is important in thinking about takesoffs and landings, because these are low-altitude operations, and virtually all stall/spin/mush accidents begin close to pattern altitude. And those who, ground-shy, instinctively pull the stick back to gain or maintain altitude, go down.
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The reference to the stall was introduced to show how incorrect your statement was; by going to the extreme of low speed one can find out what the correct action should be.
Reading this post thread, I've begun to wonder how it is that gliders actually fly. Seems impossible, them having no power and all.
Landing an aircraft is achieved by juggling the primary and secondary effects of the elevators. Slowing the aircraft down and controlling the rate of descent. I do power on landings at work sometimes when asked to land long. Just takes longer that's all; attitudes and speeds remain the same and power reduced to idle at the actual point of touchdown instead of at the flare.
Forgive me but I prefer people to understand what actually happens rather than what appears to happen.
The reference to 'ground shy' reminds me of what some-one said once about finding yourself to low to pull out of some or other manouevre. "Aim as far away as you can and try to see how low you can go!"
The technique is to avoid mushing into the ground from a position which you could fly away from.
Reading this post thread, I've begun to wonder how it is that gliders actually fly. Seems impossible, them having no power and all.
Landing an aircraft is achieved by juggling the primary and secondary effects of the elevators. Slowing the aircraft down and controlling the rate of descent. I do power on landings at work sometimes when asked to land long. Just takes longer that's all; attitudes and speeds remain the same and power reduced to idle at the actual point of touchdown instead of at the flare.
Forgive me but I prefer people to understand what actually happens rather than what appears to happen.
The reference to 'ground shy' reminds me of what some-one said once about finding yourself to low to pull out of some or other manouevre. "Aim as far away as you can and try to see how low you can go!"
The technique is to avoid mushing into the ground from a position which you could fly away from.