Speed control - pitch or power?
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There are no exemptions from the laws of nature. One way of putting it basically is : 'If sink-/climb-rate is controlled with the stick, why do we use engines for takeoff?'. This settles the pure physics for most students. 
In the 'real world' of course there are a lot more practical aspects to consider in addition. Say for instance in one extreme you fly some fuel-to-noise-converter with thrust/weight ratio > 1:1 (F-15, etc). Then of course you can control almost 'any way you want'.
Most small pistons are on the other extreme relatively slow and low-powered. One poster mentioned shortfield ops; if you're going to have a shot at SHORT shortfield ops, having the physics sorted out becomes essential. And as another poster already pointed out, in a low-altitude stall, it's no bad idea to have the reflexes right!
And then it is back to the 'power vs altitude and stick vs. speed/AoA' for the students.
(And, not least, to save their training day, the 'Any landing you can walk away from is ok. And if the next student actually can use the same plane, it was a good one')
cheers,
In the 'real world' of course there are a lot more practical aspects to consider in addition. Say for instance in one extreme you fly some fuel-to-noise-converter with thrust/weight ratio > 1:1 (F-15, etc). Then of course you can control almost 'any way you want'.
Most small pistons are on the other extreme relatively slow and low-powered. One poster mentioned shortfield ops; if you're going to have a shot at SHORT shortfield ops, having the physics sorted out becomes essential. And as another poster already pointed out, in a low-altitude stall, it's no bad idea to have the reflexes right!
And then it is back to the 'power vs altitude and stick vs. speed/AoA' for the students.
(And, not least, to save their training day, the 'Any landing you can walk away from is ok. And if the next student actually can use the same plane, it was a good one')
cheers,
I was having a bit of trouble with my landings about 18 months ago. When I had my last check flight I was told off for using power to increase speed on the approach. I realised that my problem was that I had started to use point and power without realising it. (Too much time wasted flying fast things on FS).
The instructor then demonstrated that, with the C152 trimmed for 70k, a big increase in power just made the nose come up which then destabilised the approach. He made the same point as Redbar.
Since then I have gone back to controlling speed with pitch(& trim) and rate of descent with power. My landings are now much better and confidence is restored.
I am not saying that point & power isn't a good way of doing it but, because you need to keep retrimming, I have found it much more difficult to maintain a stable approach.
The instructor then demonstrated that, with the C152 trimmed for 70k, a big increase in power just made the nose come up which then destabilised the approach. He made the same point as Redbar.
Since then I have gone back to controlling speed with pitch(& trim) and rate of descent with power. My landings are now much better and confidence is restored.
I am not saying that point & power isn't a good way of doing it but, because you need to keep retrimming, I have found it much more difficult to maintain a stable approach.
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Final 3 Greens,
First, please allow me to quote again:
All climbing consumes energy, just as all descending releases energy. I hope we agree on that! If I could control the input/output of energy with the stick, all I would have to do to take off was pull back.
Unfortunately, I have yet to see that happen; the stick contains darn little energy at start of take-off roll. We all have to use throttle to increase the energy availible, to take off. That's the physics. THEN we use the stick to obtain the wanted AoA, resulting in a particular airspeed. Sorry, but blame old Newton, not me!
Cheers, and happy landings (and take-offs)
First, please allow me to quote again:
'If sink-/climb-rate is controlled with the stick, why do we use engines for takeoff?'
Unfortunately, I have yet to see that happen; the stick contains darn little energy at start of take-off roll. We all have to use throttle to increase the energy availible, to take off. That's the physics. THEN we use the stick to obtain the wanted AoA, resulting in a particular airspeed. Sorry, but blame old Newton, not me!
Cheers, and happy landings (and take-offs)
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Join Date: Oct 1999
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No matter what method pilots develop later on, I'd recommend all students to use pitch for speed, power for rate of descent. You have to have a 'method' to learn the basics, and for light singles this one works.
I'd be surprised if PPL instructors taught anything different.
SSD
I'd be surprised if PPL instructors taught anything different.
SSD
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Redbar
I think you missed my point mate - I wasn't arguing physics, just playing around with words
Anyway, I'm pleased to have learned that airliners don't obey the known laws of physics. I'm off to flat earth lessons next.
SSD
Agree with you view. pitch for speed, power for sink is safe for students and works well in light singles.
I think you missed my point mate - I wasn't arguing physics, just playing around with words
Anyway, I'm pleased to have learned that airliners don't obey the known laws of physics. I'm off to flat earth lessons next.
SSD
Agree with you view. pitch for speed, power for sink is safe for students and works well in light singles.
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This is a really interesting thread, Ive been thinking about what I do myself, but Im afraid I just....erm...sort of .....do it naturally.......as needed for a smooth approach etc. and I cant remember what I was taught!!
No doubt the next time I fly I shall probably spend time trying to work it out
Is there by any chance a copy of Mr Farley's article available online? Flyer is a little hard to come by in France!!
Regards, SD.
No doubt the next time I fly I shall probably spend time trying to work it out
Is there by any chance a copy of Mr Farley's article available online? Flyer is a little hard to come by in France!!
Regards, SD.
