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-   -   Attitude = speed control/power = pitch (https://www.pprune.org/private-flying/484771-attitude-speed-control-power-pitch.html)

EGKB 8th May 2012 15:35

I've landed myself 4 times successfuly, I know about flaring, maintaining speeds. This isn't about flying ability. All of this has stemmed from the fact I don't agree with a specific technique for ME.

The technique clearly works as most people use it, but it doesn't work for me. It makes me a worse and more unsafe pilot. So why make me do it still?

dublinpilot 8th May 2012 15:35

I think one of the reasons why attitude = speed and power=rate of climb is thought to new students, is because of the inerita of most aircraft.

The concern being that an inexperienced pilot finds themselves veryslow on final, and attempt to correct the situation simply by adding a bit of power. Even adding lots of power will be of no use in most aircraft, unless you fix the attitude of the aircraft.

If you get attitude=speed right in your head, then your first reaction will be to push the nose down which will be the quickest way of increasing your speed. (If you are experienced you'll also fix the power at the same time in anticipation of changes needed as a result of the pitch change.)

If you learn power=speed, then your first reaction might just be to increase power and it could end in disaster.

As you get more experienced you'll find yourself able to use both and thinking about both all the time (and eventually as PilorDAR says, eventually not thinking about either, but doing both by instinct).

Your instructor doesn't want you to do one item, then wait before doing the other. They want you to do both at the same time, but want you to get your instinct to be "if slow push the nose down" as it's the action that is likely to result in the fastest acceleration. Increasing power alone might be ineffectual if your nose is already too high.

Pilot DAR 8th May 2012 15:37


I don't like the technique and it makes lfie harder for me, if I HAVE to learn it I WILL, if not then I won't
So you HAVE to learn to fly then? (but only the techniques you like.....)

One day you'll be alone in an airplane, with things going wrong, and you'll be very very scared. You'll be trying to remember the wisdom offered you along the way, to help you out of the situation, but it will be muddled in the tangle of your vigorous retorts.....

Keep things clear, learn what you're taught, it's easier to remember fast and right, later...

EGKB 8th May 2012 15:39

" use both and thinking about both all the time "

Thanks for your post sir, I think confidently what I've quoted is what I'm doing already. What happened is I thought about it and it became more difficult.

"You are now breathing" - Weird how you notice yourself breathing and it's almost unnatural and forced...

Armchairflyer 8th May 2012 15:42

The somewhat simplified "pitch = airspeed, power = climb/descent rate"-idea might not appeal to you, but IMHO there are two good reasons for teaching it (besides the fact that it is largely correct).

First, in the usual low-performance PPL-training airplane, pitch has a more immediate effect on airspeed than power, so if you need speed quickly, pitching down will produce the desired result faster than adding power.

Secondly (and relatedly), it's a safety net. If you ever get too slow ("mushing regime" or "back side of the power curve", in case you want to search for more detailed explanations) on one of your first solo approaches (which is of course a purely theoretical assumption for an outstanding top gun in the making ;-)) and get too low, instinctively adding power to gain airspeed and pulling back on the yoke/stick to arrest the descent can turn out so bad as to produce a power-on stall and probably even a spin in adverse circumstances, almost certainly resulting in the loss of a low-performance airplane and a high-potential student. If you acquire the habit of countering a too-low airspeed by lowering the nose first and adding power later (and that is something you need to consciously train), you unload the wing and get out of the mushing regime, greatly reducing the risk of terminally damaging yourself and the airplane.

Torque Tonight 8th May 2012 15:51

In typical SEP aircraft, speed is much more easily controllable by pitch attitude than power. With draggy, often low powered light aircraft, speed response to throttle control may be laggy and ineffective, whereas changing the pitch attitude will instantaneously create an acceleration or deceleration as required. After that, the rate of climb or descent is related directly to the power setting. In a low / slow situation on an approach pulling up to correct the vertical profile and adding power for speed could result in a worsening situation by getting on the wrong side of the drag curve and even stalling on approach.

The pitch for speed technique is taught because it is far more appropriate for the handling properties of SEP aircraft than the alternative. These are the foundations of all your future flying, so it's a good idea to take onboard what the instructor teaches and not devise your own alternatives. After a short while you'll be moving the stick and throttle fairly instinctively anyway.

The thrust for speed technique is appropriate to certain other classes of aircraft that have rather different handling, performance and stability qualities compared to SEP. Don't overcomplicate things at your early stage.

And seriously, a top tip, be very wary of overconfidence and an I know best attitude. History has shown that it often leads to smoking craters.

dublinpilot 8th May 2012 15:52

EGKB,

It's about getting your instincts correct.

Someday you may find the stall warner go off unexpectedly. Perhaps you had your head down looking at the map, or trying to replan in nasty weather, or diagnose a problem. Doesn't matter really....you'll have fecked up and let the speed get too slow.

If you've got your instinct to be speed is set by attitude, then your first reaction will be to push the nose down...this will happen by instinct before you've even looked up and started to diagnose the problem.

If your instinct is to increase power it might not end well.

This is why your instructor wants you to try and get your instinct to be to push the nose down for speed.

As I said, they do not want you to change pitch, then wait for a change in rate of desent, then change power. They will be happy for you to change both at the same time provided you get your instinct right.

Instead of being confrontential about it and refusing to work on your instinct, why not have some fun with it?

Have a go with your instructor, where once you get onto final, you have to maintain your approach speed -2kt/+5 kts, but you are only allowed one throttle change before reducing power fully for the flare. This will help build your instinct to control your speed with pitch changes.

If you really want to you could try doing the same the other way around later. (but best not to until you are comfortable withthe first way). ie. Hold a constant pitch, and change power for speed. You'll see that you need large power changes to hold the speed within such a narrow band.

Genghis the Engineer 8th May 2012 15:54

I'm reminded of an accident I was involved in investigating a few years ago. Type was a Rans S6: smaller and lighter but basically the same shape and performance as a C150, pilot was a low hour PPL, maybe 100 hours. He got too slow on approach, and also somebody taxied onto the runway in front of him.

So he put on full power to go around. The aeroplane pitched up (due to pitch change from power) through the critical angle of attack, stalled and yawed, and hit the ground just to one side of the runway in what was probably an incipient spin. Fortunately he, his passenger, and the bystander he hit all lived - although the CAA sponsored prosecution for reckless endangerment was unpleasant.


I've landed myself 4 times successfuly, I know about flaring, maintaining speeds. This isn't about flying ability. All of this has stemmed from the fact I don't agree with a specific technique for ME.
Gosh! 4!

Look around PPrune and you'll find threads where people with several thousand landings each are arguing with each other about the best way to do it. And taking useful things from the discussion.

G

Weirdfish 8th May 2012 16:03


If I can run 100m in 11.5s using my own technique and can only do 13s using the trainers technique, which technique do I choose.

I can see your reasoning, however, that is as it stands now. It could be that by learning by the trainers technique you could eventually do it in under 11.

Just a thought. :)

EGKB 8th May 2012 16:07

Thanks guys, nope I'm all ears! Probably doesn't sound like I'm taking anything away, but I am! :)

Heston 8th May 2012 16:13

Well I hope for your sake that you are a troll.:rolleyes: you certainly don't understand how an aircraft flies - and the point is that techniques are developed by people who do understand how aircraft fly.:ugh:

Would you care to tell us what aircraft you are learning on, and what approach speed you were using?

H

EGKB 8th May 2012 16:18

I know how aircraft fly/what inputs do what and so on.....

Genghis the Engineer 8th May 2012 16:23


Originally Posted by EGKB (Post 7178153)
I know how aircraft fly/what inputs do what and so on.....

No, you don't.

You have been shown the very basics, and got a simple initial understanding which, if you show some intellectual humility and put in some hard work, you may build upon over the next few hundred hours to start to develop a reasonable understanding.

You do not know. Nobody at your stage of training and education "knows". Indeed, there are people with 10,000 hrs who still have stuff to learn about effects of controls - and would be very happy to admit it.

Just like the very simplistic schooling in subjects like maths and science you'll have seen at GCSE level, the early parts of flying training are massively dumbed down - and certain things are just taught "this way" to make early training survivable and efficient.

There are people posting on this thread with thousands of hours, commercial licences, and degrees in aeronautical engineering. At-least three people have all three. I'm willing to bet that none of them are prepared to post here claiming that they have as full an understanding of how aeroplanes fly as they would like to have, and that there are no gaps in their knowledge which could bite them.

G

Pilot DAR 8th May 2012 16:49


I know how aircraft fly/what inputs do what and so on....
EGKB, I'm going to call you on that, and challenge you:

What follows are charts of my flight test results of a modified Siai Marchetti 1019. They show why that aircraft could demand great piloting skill during a STOL takeoff (specified as to be done at flaps 30). What would the pilot of this aircraft experience right after liftoff flaps 30?

To help your understanding; "Tq" means engine torque, which equates to the engine power selected. "pounds" is the control force the pilot experiences in pitch.

http://i381.photobucket.com/albums/o...Flaps0_001.jpg

http://i381.photobucket.com/albums/o...laps30_001.jpg

http://i381.photobucket.com/albums/o...laps60_001.jpg

thing 8th May 2012 16:52


Firstly, we're not talking about a glideslope, we're talking about a student pilot on a visual approach.
Ah sorry, my mistake. By the way the thrust of my post was that I don't really understand the 'push forward for glideslope' point of view when it seems better to just reduce power and let the nose sink. However I bow to the collective experience of those far more experienced than me which of course is one of the benefits of this place for new PPLs like moi.


After a few hours you tend not to think about this and you just fly the aircraft as you would drive a car. You don't 'think' about gear changes, do you?
I don't think about it, it's just what I perceive I'm doing. Geng is probably right, I'm unconsciously doing all the other stuff as well.

Genghis the Engineer 8th May 2012 16:56

That's sporting DAR ! Once EGKB has given his opinions, I'd be interested in your role relation on that and where you placed it relative to 23.175

G

chipmeisterc 8th May 2012 16:59


What follows are charts of my flight test results of a modified Siai Marchetti 1019. They show why that aircraft could demand great piloting skill during a STOL takeoff (specified as to be done at flaps 30). What would the pilot of this aircraft experience right after liftoff flaps 30?
Pilot DAR too easy! Obviously if he had to flap the wings 30 times he's going to be pretty tired!!

Genghis the Engineer 8th May 2012 17:11


Originally Posted by Silvaire1 (Post 7178229)
It'd be interesting to retract 30 degrees of flaps quickly on that Turbo Bird Dog at 50 kts. Good thing the delta is only 6 lbs.

I suspect that taking flaps from 60 to 30 in a full power go-around would be considerably more than just "interesting"!

G

madlandrover 8th May 2012 17:22


when it seems better to just reduce power and let the nose sink.
And here we have the crux of this discussion - not aimed at you personally thing ;) just a convenient quote. That technique may have worked for you so far, but as a way to fly an ILS point & power works better across the board. Using power to control pitch attitude is fundamentally incorrect, since pitch attitude can only be controlled (as opposed to affected) by elevator. Imagine flying the approach in something with rather less pitch & power couple than you're used to, or on an excitingly unstable day - point & power would require far less work & be more accurate.


It makes me a worse and more unsafe pilot. So why make me do it still?
Next... Again, not a personal attack, but a fundamental misunderstanding. Your instructors are attempting to make sure that you can master several different techniques effectively, rather than being so bound into one technique that the idea of using anything else turns you into a shaking wreck. You will find point & power somewhat tricky during glide approaches, for example :E

thing 8th May 2012 17:50


And here we have the crux of this discussion - not aimed at you personally thing http://images.ibsrv.net/ibsrv/res/sr...lies/wink2.gif just a convenient quote. That technique may have worked for you so far, but as a way to fly an ILS point & power works better across the board. Using power to control pitch attitude is fundamentally incorrect, since pitch attitude can only be controlled (as opposed to affected) by elevator. Imagine flying the approach in something with rather less pitch & power couple than you're used to, or on an excitingly unstable day - point & power would require far less work & be more accurate.
I'll bring that up at the club, I'm sure you are probably right. Thing is I can't remember now what technique I was taught!! I just kind of fly down the glideslope and it all comes together. Not a very technical description I know but I don't have degrees in Complicated Things.

Edit: But having just thought about it, aren't I doing the same thing the other way around? Instead of point and power I'm doing power and point. I think.


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