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Old 8th May 2012, 08:00   #21 (permalink)
 
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Firstly, we're not talking about a glideslope, we're talking about a student pilot on a visual approach.

Secondly, I think it's you thing. I reckon you are pushing or re-trimming to maintain speed in most light aeroplanes with a 300 rpm reduction.

G
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Old 8th May 2012, 08:42   #22 (permalink)
 
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Thing, there are some aircraft that will react as you describe, under certain circumstances. However, the overriding point is that if you change one of the controls, it is highly likely (nay, almost definite) that you must do something with another.

Looking at this another way, if you choose to fly 'point and power' and discover you are too slow, you will add power. In order to counter the subsequent change in attitude (dare I say AoA) you will need to change the pitch. In reality, you are actually reducing AoA to counter the increased speed you have given yourself. You could get exactly the same effect by firstly changing pitch (thus increasing airspeed) and then increasing power in order to retain/attain a particular rate of descent.

One final point. 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?
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Old 8th May 2012, 08:45   #23 (permalink)
 
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Thing

I go with Genghis on that. I am sure you have tried an exercise at altitude of flying an airspeed in the descent?
You cruise at 100 kts and push the nose over! To maintain that 100 kts you have to bring back power. Note descent rate.
Now push the nose over even further! again to maintain your 100 kts you will have to bring back power even further. Note descent rate now!!
Push the nose even further and you maybe back on the stops with power you can no longer maintain 100 kts clean without chucking out some drag as now the energy you are getting from the airframe exceeds the amount required to maintain the 100 kts.
You can no longer play the two energy sources as your powerplant is at idle and you cannot reduce that further.
To maintain the 100 kts all you can do is to reduce the power from the second energy source by reducing the descent.
Of course you could hang out drag but thats another subject.

Pace
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Old 8th May 2012, 08:47   #24 (permalink)
 
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Quote:
It's not arrogance at all, it's completely subjective, some methods work for some, some for others.

I'm not saying pitch doesn't control speed, it does. But to me everything is backwards, there's a reason why there's an elevator on the plane to control pitch, it worked for me perfectly on all approaches/landings so far except for today when I tried the opposite technique....

I'm not sure if they teach the same technique, I haven't landed with the other instructor, he was on my first lesson and I wasn't taking much no on the landing as to what he was doing.
EGKB What are you going to do then when you are short final and a little high and fast, pitch the nose down at the ground and pull the throttle to idle? In a Piper or Cessna you can be pretty sure that isn't going to get you down any time fast.

Conversly pitching up away from the runway ( yep its counter intuitive ) to get your speed under control, and reducing the throttle to idle to increase your rate of decent and you will start coming down pretty sharpish.
..Remember also that pitching up is also going to increase your AoA which is going to also create more drag and help slow you down. Pitching down is going to decrease your AoA.

My advise, don't presume that you know better than your instructor, and don't give up on this technique just because its counter intuitive...are you going to do this with all other elements in the syllabus as well? Pitching for speed will give you a much greater control of your approach speed and save you endless balloons / floats down the runway.



Your elevator is your AOA control not your pitch control.
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Old 8th May 2012, 09:11   #25 (permalink)
 
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EGKB, please don't take this the wrong way, this is friendly advice.

Questioning your instructor on PPRuNe at an early stage of your training and then declaring after 2 responses to the thread that you are never going to use the landing method taught does not in my view show an appropriate willingness to learn.

You cannot pass a PPL solely from advice on here. You need to develop trust in your instructor. Why not ask him/her to explain on the ground and then demonstrate in the air the reasons for the methods taught?
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Old 8th May 2012, 09:24   #26 (permalink)
 
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Well Mariner9 got there before me. Two bits of advice (both already mentioned) from me:
1. Ask your instructor to explain and demonstrate (he or she will respond well to such a request). Then do what you are told.
2. Get a copy of "Stick and Rudder" by Langeweische and read it several times.

Oh alright three bits of advice:
3. Don't confuse yourself by asking folk on the Internet to give you advice unless you know their credentials

Have fun

H
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Old 8th May 2012, 09:32   #27 (permalink)
 
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Quote:
Originally Posted by Heston View Post
Well Mariner9 got there before me. Two bits of advice (both already mentioned) from me:
1. Ask your instructor to explain and demonstrate (he or she will respond well to such a request). Then do what you are told.
Yes

Quote:
2. Get a copy of "Stick and Rudder" by Langeweische and read it several times.
No, for a student pilot at this stage in EGBK's training, use a current training book such as that by Jeremy Pratt. Stick and Rudder, which is old, and does not reflect latest thinking is well worth reading - for an experienced pilot who has a frame of reference to hang it on. It's the wrong thing for a student PPL.

Quote:
Oh alright three bits of advice:
3. Don't confuse yourself by asking folk on the Internet to give you advice unless you know their credentials

Have fun

H
I'm very happy to state mine (indeed I do in my profile, but can add 64 types as PiC and 4-figure hours if that helps), but I'd also comment that nobody's paying for my advice here, and therefore it's worth approximately what you paid for it.

The bit about having fun on the other hand I agree with utterly.

G
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Old 8th May 2012, 09:56   #28 (permalink)
 
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Mariner Heston

Please feel free to point out any incorrect information from whoever in the thread as in any forum discussion that is how we get to the truth.
I for one am happy to stand corrected?

Pace
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Old 8th May 2012, 10:23   #29 (permalink)
 
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GtE - yes of course you are right about reading current PPL training books as the main source of reference (I made the assumption that a PPL student would already be reading them, but on reflection I see that that may not be so). But I can't agree with steering clear of Langeweische because its the only book I know of that actually explains in sufficient detail most of the answers to questions that learning pilots ask that are phrased something like "Yes, but WHY does it do... ?" As L says somewhere in the the intro, its written for pilots to understand, with only enough aeronautical theory and no more.

Pace - its not about incorrect information: its perfectly possible to be confused by multiple explanations all of which are correct in their own way.

H
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Old 8th May 2012, 10:32   #30 (permalink)
 
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Quote:
Pitch does control speed.

Power does control rate of climb or descent.
So gliders cant fly?

So when you flare with the throttle closed you cannot control ROD by pitch?

So in a low level go around just above the runway after a large bounce you will pitch down to increase the speed?

So if the engine stops you cannot control ROD at all?

Thats the problem with making unqualified statements!

You need to understand what the PRIMARY method of controlling ROD/height and airspeed on finals is but also understand that a combination may need to be used, such as in the Go Around. You also need to understand that both can be used the other way round as a secondary method of controlling height and speed!
.
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Old 8th May 2012, 10:40   #31 (permalink)
 
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Quote:
Please feel free to point out any incorrect information from whoever in the thread as in any forum discussion that is how we get to the truth
I was not questioniong your (or indeed anyone's) responses Pace, I was questioning the OP's stated intention to use a PPRuNe thread to disregard his instructor.
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Old 8th May 2012, 10:44   #32 (permalink)
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Do this, and that happens....

At early stages of learning to operate any machine, you use your very modest judgement to figure out what you need it to do, then you use your even more modest skill to control the machine to do it. So you're figuring out what to make your hands and feet do to make the machine move. Two stages. This demands a simple understanding of "do this to make that happen". This is particularly true of aircraft, which are subject to more forces and variables than most machines. That's what instructors are taught to teach you, and you're paying for it, so you may as well listen.

When you reach the stage of hundreds of hours of flying skill, you'll find that you can control the plane with your mind directly, and thinking about what your hands and feet are doing is not necessary. These understanding aids will not be needed anymore, but you're not there yet.

When your instructor demonstrates slow flight, pay particular attention to these characteristics. (Really, landing is slow flight anyway, at its later stages). With the aircraft flying level with full flaps, lots of power, and very little of Pace's very important potential energy, the elevator control will control pitch attitude very nicely, because there'll be no energy to turn into a climb. Power changes will cause the aircraft to climb or descend with surprisingly little pitch attitude change. If you're really neat about doing this, the effects of P factor can be observed too.

When you're flying faster, the effects are more subtle, and likely to be seen to overlap each other. Follow your training......
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Old 8th May 2012, 10:52   #33 (permalink)
 
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Heston

But that is the whole point re these discussions is that we do dissect subjects ! Some information is wrong and is usually corrected at some point.
That is why it is important to look at the whole thread and postings and never take one opinion as Gospel. In the end there is usually a concensus
As for students of course their main contact is their instructor and they cannot fight the instructor by going off on their own tangent! That does not mean the student should not question or ask for more detailed explanation as to why??
I totally agree that with an inexperienced pilot in a low powered draggy aircraft pitch for speed has to be the safe way as that is the most secure way of keeping away from a high AOA high drag situation.
My only point is that the true picture is energy management and pitching for speed is not the full picture and neither is power for speed.

Pace

Last edited by Pace; 8th May 2012 at 11:08.
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Old 8th May 2012, 11:04   #34 (permalink)
 
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It is disappointing though that a student has to come onto a forum to discuss something that should be discussed with the instructor. If you cannot communicate with your instructor how can you learn to fly properly?
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Old 8th May 2012, 11:33   #35 (permalink)
 
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Originally Posted by Pull what View Post
It is disappointing though that a student has to come onto a forum to discuss something that should be discussed with the instructor. If you cannot communicate with your instructor how can you learn to fly properly?
A bit of a design characteristic of the OP I think. He has previously expressed strongly some rather incorrect views concerning, for example, how many landings are likely to be needed before solo. Not atypical behaviour of male homo-sapiens in the 16-25 bracket.

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Old 8th May 2012, 12:53   #36 (permalink)
 
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Negative Genesis,

I was simply shocked at how many T&G's one pilot needed, 118 I think it was. And I simply questioned why it was so high, and some people agreed that it's quite high...
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Old 8th May 2012, 13:02   #37 (permalink)
 
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Mariner9,

Thanks for the post, I disagree. I have a great willingness to learn. And I did speak to my instructor about the technique, he said it's the way he teaches it. And as others have said it's not a law, you don't HAVE to use that technique, each to their own, that makes things harder for me. For some it might make it easier, but it's not mandatory is it?

"You need to understand what the PRIMARY method of controlling ROD/height and airspeed on finals is but also understand that a combination may need to be used" - This is what I agree with, I know you guys are more experienced than me, and I guess I might sound a little arrogant, but I'm simply investigating a technique and stating my opinion on it.

I pulled the yoke back to go higher and forward to go lower, increased power to increase speed and visa versa. That has worked for me, instructor said my app was perfect, then I tried the opposite and everything was fine except my mind got clogged up thinking about opposites/doing things in the reverse order.
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Old 8th May 2012, 13:10   #38 (permalink)
 
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I pulled the yoke back to go higher and forward to go lower, increased power to increase speed and visa versa. That has worked for me, instructor said my app was perfect, then I tried the opposite and everything was fine except my mind got clogged up thinking about opposites/doing things in the reverse order.
Again I echo what I said before and when you find yourself high and fast on short final, the above technique is only going to cause you more problems!
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Old 8th May 2012, 13:37   #39 (permalink)
 
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I'm not an instructor but I've been trained various ways and fly jet transport aircraft now.

Like the original poster, I found that concept utterly confusing in the early days, to the point that I would sit and think about what needed to be done given what I was seeing out the window and confirmed with the ASI. It left me massively behind the aircraft and as such, I haven't entertained the concept since.

The easiest way I found to fly an approach that works in your C150 to your heavy jets is use pitch and power in unison. Imagine a piece of string connects your hand on the throttle to the hand on the yoke. If you move one, you move the other in the opposite direction. A bit like when you swing your arms when you run; when one arm goes forward, the other goes back. Of course, in this case, those movements can be as minimal as a squeeze of pressure or a 2mm move in throttle.

If you're high, you lower the nose slightly and simultaneously reduce the power slightly. Once you're on the correct path, you'll raise the nose slightly, not forgetting that you'll need an increase in power to maintain the speed. The same goes for being too fast or too slow. If you alter one, alter the other.

Two caveats to that. One is that you'll find, as you get more experienced, that you can work combinations of that technique to be more efficient and effective but it's a good process to hang your hat on to start with. Particularly, you'll find that a small change in power on an approach that is spot on in pitch requires, in some cases, no change in pitch if you were looking to alter your approach speed by a few knots.

The second is that you should be wary of bringing your own techniques, and those of people on an anonymous forum, to your training regime. It can in some circumstances do more harm than good, especially if you haven't consulted your instructor or the school. That said, it's a recognised technique that works for most but can be fairly dependent on experience.

Good luck!
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Old 8th May 2012, 13:38   #40 (permalink)
 
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each to their own, that makes things harder for me. For some it might make it easier, but it's not mandatory is it?
When you've got a few hundred hours is the time to start deciding what technique suits you best. When you have a few tens and haven't soloed yet, the person best equipped to make that decision is the instructor.

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