An acceptable landing...
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Joined: Feb 2000
Aviation Qualifications: CPL
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From: UK
What next: nothing personal (although I think that the theory I was spouting was pretty much from the JAR CPL/ATPL syllabi which I think are the same in the UK and Germany). You perhaps got me at a grumpy moment, but equally contradict me any time - nothing like a good aviation technical argument.
8282: whatever else you did, you got a great discussion going. My complements for that. I do agree with others about the flat approach, but a great many instructors do teach light aeroplane flying as if it was airliner flying so this is almost certainly their fault not yours. But get rid of the hi-viz!
Pace: I'm pretty certain that any experienced pilot, such as yourself, will use power and pitch (and possibly other services) holistically to control speed and flightpath. However, it used to be standard teaching to do RoD/ flightpath with power and speed with pitch; in recent years that has reversed, and if you're going to be regimented about it, certainly that works best on an instrument approach in a jet: it is much more debateable on a visual approach with (a) piston engine(s). I'd venture that anybody without a lot of hours both overall and on type, probably should stick to one or the other.
Everybody: I was taught some years ago that a landing is never over until ALL of the bits have stopped moving. It's an adage that's served me well so far.
Also, the use of flat powered approaches operating power against services should be regarded as more of a jet thing - in most turbine aeroplanes it is quicker to get rid of gear and flap than it is to spool an engine up from near-idle. In most piston engined aeroplanes, particularly anything with electric flaps, the converse is true.
G
8282: whatever else you did, you got a great discussion going. My complements for that. I do agree with others about the flat approach, but a great many instructors do teach light aeroplane flying as if it was airliner flying so this is almost certainly their fault not yours. But get rid of the hi-viz!
Pace: I'm pretty certain that any experienced pilot, such as yourself, will use power and pitch (and possibly other services) holistically to control speed and flightpath. However, it used to be standard teaching to do RoD/ flightpath with power and speed with pitch; in recent years that has reversed, and if you're going to be regimented about it, certainly that works best on an instrument approach in a jet: it is much more debateable on a visual approach with (a) piston engine(s). I'd venture that anybody without a lot of hours both overall and on type, probably should stick to one or the other.
Everybody: I was taught some years ago that a landing is never over until ALL of the bits have stopped moving. It's an adage that's served me well so far.
Also, the use of flat powered approaches operating power against services should be regarded as more of a jet thing - in most turbine aeroplanes it is quicker to get rid of gear and flap than it is to spool an engine up from near-idle. In most piston engined aeroplanes, particularly anything with electric flaps, the converse is true.
G
Joined: Jan 2001
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From: In the boot of my car!
Genghis
As you are aware the pitch for speed or power for speed arguement has raged for a long time.
I do not think either is correct! All that is correct is that both allow you to tap into potential energy.
Being conditioned to one or the other could in certain situations lead to problems but being open to tapping into both, playing both has to be the most effective way of extracting the maximum from the airframe and engine when needed.
Low powered aeroplanes with low experience pilots are better taught the pitch for speed as that will protect them from getting into high drag situations and away from the stall.
But with more experience I feel pilots should regard both as energy sources they can use and as such regard them as one.
Pace
As you are aware the pitch for speed or power for speed arguement has raged for a long time.
I do not think either is correct! All that is correct is that both allow you to tap into potential energy.
Being conditioned to one or the other could in certain situations lead to problems but being open to tapping into both, playing both has to be the most effective way of extracting the maximum from the airframe and engine when needed.
Low powered aeroplanes with low experience pilots are better taught the pitch for speed as that will protect them from getting into high drag situations and away from the stall.
But with more experience I feel pilots should regard both as energy sources they can use and as such regard them as one.
Pace
Joined: Oct 2004
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From: UK
What is meant by being behind the curve?
At a safe height, slow the aircraft down to about 80 Kts and maintain level, check the power setting.
Now slow it down to about 70Kts and maintain level, again check the power setting.
Repeat this until you find the point where you need more power to maintain level at the lower speed, than at the higher speed; you are now behind the drag curve.
Now apply full power, maintain level and see what happens - basically very little, until the aircraft accelerates slowly over and away from the drag curve. The reason why we use full power for a stall recovery.
Joined: Sep 2009
Aviation Qualifications: PPL
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From: N.YORKSHIRE
Some interesting comments. Here's one of my landings. Fairly typical, apart from the snow. Approach flown at around 7°. Full flap and no Hi-vis.
(Speed is pitch controlled). Stall warner inop. Comments welcomed.
(Speed is pitch controlled). Stall warner inop. Comments welcomed.
Joined: Jan 2009
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From: Oxford, UK
Well, flying mac, I'm glad you were able to stop before you taxied into the hangar!
Seems to me with all this discussion of the perfect approach, whether to touch down fully stalled or with flying speed, does not give sufficient emphasis to the weather conditions of the day. Maybe airlines can land happily with a 15 mph tailwind, but it don't half make a difference to a light aircraft, or a glider. And a 20 knot crosswind can be a zero headwind.
Still remember a nice single anxious to get down where his wife was waiting with the car, airfield unattended in lousy viz, everyone else had packed up flying for the day. We all watched him approach with an interesting tailwind, he didn't touch down untill at least half way along the runway, and then ended up in the hedge. Bent his airplane and his ego and he blamed it because nobody had told him over the radio what the wind strength and direction were.
Seems to me with all this discussion of the perfect approach, whether to touch down fully stalled or with flying speed, does not give sufficient emphasis to the weather conditions of the day. Maybe airlines can land happily with a 15 mph tailwind, but it don't half make a difference to a light aircraft, or a glider. And a 20 knot crosswind can be a zero headwind.
Still remember a nice single anxious to get down where his wife was waiting with the car, airfield unattended in lousy viz, everyone else had packed up flying for the day. We all watched him approach with an interesting tailwind, he didn't touch down untill at least half way along the runway, and then ended up in the hedge. Bent his airplane and his ego and he blamed it because nobody had told him over the radio what the wind strength and direction were.
Joined: Dec 2005
Aviation Qualifications: PPL
Posts: 491
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From: West Sussex, England
Could be the perspective, but looks like FlyingMac made a massive 'bomber' circuit and a rather low flat approach which didn't (apparently) improve/ shorten the landing roll ?
Hearing the stall warner (in a strip operated Jodel) was a neat aural guide to flare speed without having to look down at the panel.
The stall warner is just that, not the actual stall but some useful mph above the wing drop, so our tyro did rather well I thought, if it was while u/training !
Hearing the stall warner (in a strip operated Jodel) was a neat aural guide to flare speed without having to look down at the panel.
The stall warner is just that, not the actual stall but some useful mph above the wing drop, so our tyro did rather well I thought, if it was while u/training !
Last edited by mikehallam; 11th July 2011 at 10:51. Reason: English corrected.
Joined: May 2001
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From: UK
It is interesting for me both approaches look very flat. Watching aircraft come and go generally I think there is a tendency for more pilots to land flat, so perhaps teaching methods have changed? Personally I aim to be above the PAPIs on the approach until very late final and definitely look to stall the aircraft on (unless there is some good reason not to do so).
Each to there own.
Each to there own.
Joined: Oct 2004
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From: UK
The500man
I think you've missed the point! Power is used to minimise height loss, but what I was referring to is Why we use full power as opposed to any other power setting. In a typical light aircraft we demonstrate the use of Full Power to overcome the high initial drag associated with being on the wrong side of the drag curve, or we will not minimise the height loss.
...is to minimise height loss and is otherwise not required.
Joined: Mar 2006
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From: Kent UK
It is interesting for me both approaches look very flat. Watching aircraft come and go generally I think there is a tendency for more pilots to land flat, so perhaps teaching methods have changed?
There's something about "dragging it in" that I inherently dislike.
Joined: May 2001
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From: UK
Yes, I agree and something satisfying about the round out and gentle kiss with the ground 
.
In fact I often find myself driving twins the same way.
However to be fair steep approaches require a degree more confidence and cant be considered as stable as a constant aspect approach positioned firmly on the localiser.
Equally I have seen a fair few flying approaches that are really flat. Where does this tendency come from - do we for some reason feel inherently more comfortable flying flat approaches or does it come back to the way we were taught. If you send a newish PPL off to an unkonwn strip with out the benefit of PAPIs where is he most likely to position himself on the approach?
.In fact I often find myself driving twins the same way.
However to be fair steep approaches require a degree more confidence and cant be considered as stable as a constant aspect approach positioned firmly on the localiser.
Equally I have seen a fair few flying approaches that are really flat. Where does this tendency come from - do we for some reason feel inherently more comfortable flying flat approaches or does it come back to the way we were taught. If you send a newish PPL off to an unkonwn strip with out the benefit of PAPIs where is he most likely to position himself on the approach?
Joined: Jan 2001
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From: In the boot of my car!
I would love someone here to explain the theory and physics of pitching for speed ?
I can understand the benefits in protecting low time students by using pitch to keep well away from high drag/stall situations.
I can understand in V low powered high drag aircraft that pitching for speed becomes more important as they are power limited.
I would also like someone from the power for speed club to explain their theory and physics?
Ok I fly corporate business jets as a Captain but I also fly twin engined pistons and on occasions single engine pistons.
Lets get away from the jets and look at a piston twin also on autopilot locked on the ILS.
The graph of such an approach would show a fairly consistant descent profile ie the aircraft will be pitching to maintain that profile NOT for speed.
In that scenario speed will be controlled by adding drag ie the flaps and gear and power.
Obviously in that scenario pitching for speed has gone out the window! As on a set glidepath with a given amount of drag the only speed adjuster will be power. Has anyone designed an autopilot based on pitching for speed?
On the flip side of the coin and aircraft with a lot of drag and a high angle of attack may not have enough power in its own right to increase speed and in that situation pitching will recover speed.
The sooner we regard the elevator and the throttle as means of tapping into energy the more accurate we will become on realising that both camps are incorrect?
Someone prove me wrong?
As for the arguement against powered approaches re glide approaches?
In the glide approach with the engine throttled back you wont know you have a power problem until you need it.
Your stall speed will be higher than in a powered approach.
Your chances of missing your touchdown point will be greater.
Finally in the event of an engine failure never fixate on reaching a point as that is the surest way of hitting the houses on the approach.
Pace
I can understand the benefits in protecting low time students by using pitch to keep well away from high drag/stall situations.
I can understand in V low powered high drag aircraft that pitching for speed becomes more important as they are power limited.
I would also like someone from the power for speed club to explain their theory and physics?
Ok I fly corporate business jets as a Captain but I also fly twin engined pistons and on occasions single engine pistons.
Lets get away from the jets and look at a piston twin also on autopilot locked on the ILS.
The graph of such an approach would show a fairly consistant descent profile ie the aircraft will be pitching to maintain that profile NOT for speed.
In that scenario speed will be controlled by adding drag ie the flaps and gear and power.
Obviously in that scenario pitching for speed has gone out the window! As on a set glidepath with a given amount of drag the only speed adjuster will be power. Has anyone designed an autopilot based on pitching for speed?
On the flip side of the coin and aircraft with a lot of drag and a high angle of attack may not have enough power in its own right to increase speed and in that situation pitching will recover speed.
The sooner we regard the elevator and the throttle as means of tapping into energy the more accurate we will become on realising that both camps are incorrect?
Someone prove me wrong?
As for the arguement against powered approaches re glide approaches?
In the glide approach with the engine throttled back you wont know you have a power problem until you need it.
Your stall speed will be higher than in a powered approach.
Your chances of missing your touchdown point will be greater.
Finally in the event of an engine failure never fixate on reaching a point as that is the surest way of hitting the houses on the approach.
Pace
Joined: Aug 2000
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From: Near Stuttgart, Germany
Hello!
No, it hasen't! Because once you are fully configured (depending on what you have - gear, flaps, prop) it's back to pitch and power again. If only for the remaining two or three miles.
Mr. Cessna has, at least sort of. Try flying an approach in "FLC" mode on your Citation (FLC (=flight level change for the non-Citation-flyers) essentially is pitch for speed!) and you will realise why no manufacturer uses this mode for approaches. Zero passenger comfort and corporate pilots who have to clean the cabin after every landing...
In our FTO, we teach both methods nowadays. Pitch for speed to students who want to become private pilots (to reduce the likelihood of stalling during finals) and power for speed to the ones who want to become commercial pilots (over 90 percent). Starting from lesson one.
Obviously in that scenario pitching for speed has gone out the window!
Has anyone designed an autopilot based on pitching for speed?
In our FTO, we teach both methods nowadays. Pitch for speed to students who want to become private pilots (to reduce the likelihood of stalling during finals) and power for speed to the ones who want to become commercial pilots (over 90 percent). Starting from lesson one.
Joined: Jul 2009
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From: London
I think you've missed the point!
Going back to the low approaches; be honest are you going to make the runway from 1000 ft while on a 2 mile final if the engine quits? How close to the runway do you need to be downwind to glide with idle power onto it? I doubt anyone flies a steep enough final from sufficient height to make the runway without an engine. If you did the "ideal" approach would be the power-off glide final.
I think we're all taught to land as close to the numbers as possible, and for good reason if you fly into short strips. Much more runway gets used up rounding out from a steep final then dragging the thing in on a flatter approach. If you get too high on final you're either going to be too fast at the threshold (pitching down) or you'll have a higher AoA (reducing power). You likely don't want either.
On the pitch/ power thing, if you are flying at the right speed, regardless of whether you are high or low you will need to change power setting to get back on profile. I don't see the point in pitching for speed. If you are too fast and too high, pitching for speed is surely going to lead to a go-around unless you pull the power and accept the higher AoA.
I maybe missing the point again though!
Joined: May 2001
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From: 75N 16E
The pitch for speed thing comes presumably because if you get slow in a spamcan, then speed will react to pitch far faster than power. On an ILS I'd use the opposite because you are flying much faster at typically 100 kts in a single or piston twin. On an ILS you pitch for glide path and power for speed. Also heavier aeroplanes are easier to fly a stabilised approach as they are less reactive to gusts and thermals to some extent.
Flying a relatively flat approach with some power also means you are approaching slower so that when you touch down you stop flying ASAP. Our stall speed (dirty) is 54 kts, s/f approch is 72 kts and normal landing is 82 kts. If you land at 82 kts then obviously the gound roll is going to be longer so it is better to come in slower (on a short runway) and to give you a more stabilised slow approach, come in with a relatively high AoA and some power.
That's my theory anyway!
Flying a relatively flat approach with some power also means you are approaching slower so that when you touch down you stop flying ASAP. Our stall speed (dirty) is 54 kts, s/f approch is 72 kts and normal landing is 82 kts. If you land at 82 kts then obviously the gound roll is going to be longer so it is better to come in slower (on a short runway) and to give you a more stabilised slow approach, come in with a relatively high AoA and some power.
That's my theory anyway!