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darn
11th Jun 2009, 20:25
Every student seems to struggle with circuits initially, but after a few lessons they've picked up the checks, the RT calls, and got the size and shape of the circuit about right.

Often they can even fly a stable approach, at the correct speed (or within 5kts) and at a sensible profile.

But its always, always the hold-off and the 'flare' that they struggle with - co-ordinating closing the throttle at the right moment, starting the hold-off at the correct height and using the rudder/aileron as necessary. All whilst trading airspeed for angle of attack to ensure a landing on the main wheels.

Basically I'm finding this the hardest part to teach, and as a relatively new FI I'd welcome any tips or advice from the more experianced FIs out there.

Thanks!

fireflybob
11th Jun 2009, 20:47
It's always worth doing another demonstration or two - they also learn by watching what you do (assuming it's correct of course!).

Also landing is about attitude - if they roundout at the right sort of height and select the correct landing attitude,close the throttle (and whilst doing so still maintaining the correct attitude and keeping straight with rudder) they shouldn't go too far wrong. Remember also at this stage we are not aiming for precision but a safe technique. Have you shown them how to go around from a misjudged flare/landing? I think this is important because they need to know how to get out of trouble if it starts going wrong. Hope this helps.

OneIn60rule
11th Jun 2009, 21:08
A factor.

Is your runway long enough to demonstrate things a bit slower?

I found one student could not get the hang of it unless he left some power on say the C-152. Things happen a bit slower that way and gives that person more time to react.

Basically, as soon as you get close enough to get on the runway, leave under 1400 RPM and just leave the power there. Things will happen but they will happen so that you have time to explain each phase.


I don't guarantee this working for everyone but it certainly helped one.

1/60

Cows getting bigger
12th Jun 2009, 06:10
Power. Too many people aggressively cut the power on final. When learning (as so eloquently put by oneinsixty) we're not aiming for precision at the beginning. Demonstrate how (and when) they should stop looking at the numbers/instruments and should now be focussed on the horizon. At this point they should commence pitching up gently to the level attitude (the one they have learnt for straight and level flight) and then arrest the inevitable sink with balanced application of more elevator together with reduction in residual power. Take the lesson to the extreme and demonstrate a landing maintaining the power setting you had on final approach.

If you try and get them to kill power on short final they will invariably get the timing wrong, the nose will drop (cows will get bigger ;) ), they will overreact with elevator and the aircraft will drop onto the ground. There is a place for glide approaches but this isn't at the early stages of Ex 13.

Tinstaafl
12th Jun 2009, 06:12
This type of questions pops up from time to time. Here's a link that might help:

http://www.pprune.org/flying-instructors-examiners/196364-what-do-you-use-trigger-roundout-flare.html

You could also use the search function for similar threads.

Tmbstory
12th Jun 2009, 07:23
At the flare height, keep looking out along the runway and back torwards the nose continually, then gently ' try not to land ' (without gaining any height) until the main wheels touch down .

Tmb

chrisN
12th Jun 2009, 17:17
After my last effort on this forum, I fear I am starting a hornets nest again, but here goes, from a glider pilot who did a PPL conversion.

I believe that landing is one of the hardest things to get right for an early ab-initio. Learning to fly straight and level myself, and later teaching other glider pilots to, was difficult enough. If they can only just manage that, how good can we expect them to be at doing a curved flight path with changing attitude and changing speed, and coping with the other things too as posted above, during flare and hold-off? Not only that, but for newbies, everything happens so fast that the brain is yards (miles?) behind the aeroplane.

A problem I had was that an instructor talked me through a landing on my fifth glider flight. He was so impressed at his own brilliant tuition and my luck in getting it right once, that he wrote up that I could do my own landings. After that, it took another 70 or so before I became consistent, because I had no mental image of what I was supposed to be doing and they all turned out different. Even after solo, it took years before my landings were still good when under pressure.

I think I would have been better off having to watch instructors do all the landings until I could remember what it was supposed to look like, as well as being sufficiently familiar with the handling to be able to reproduce it.

When I converted to power, I had the same personal problem at first too little sight of what good ones looked like until quite a lot of lessons, so they were all different at first.

(By the way, if you deal with glider pilot conversions, the change in attitude during flare, and how it looks from the relatively high seat of a Cessna 150/152, is enough different from a typical close to the ground glider seat, that it can take more getting used to than you might expect. Or maybe I was just a slow learner/converter.)

Just my 2pth.

Chris N.

Cows getting bigger
12th Jun 2009, 20:35
Chris you are right in that a glide landing, be it in a glider or a powered aircraft, is quite different. Combine this with your stated fact that in a glider your bum is far closer to the ground and the wing is far more 'sensitive', I can understand why it is not necessarily a simple task to convert from powered aircraft to glider.

PAPI-74
12th Jun 2009, 20:55
Once you are lined up just prior to take off, note the picture with the student (and even have a picture of it in the briefing) pionting out a feature, maybe a tree, to keep their focus on the horizon not the spinner. Tell them that the landing is just flying level, with a gentle sink towards the runway - whilst holding the picture burned into their memory.

Flying level - flare
Holding the picture - hold off.

It is then just upto them to suddenly 'get it'. The trick is to know when to say nothing and when to gently guide. The more relaxed you are, the better they will pick it up and enjoy the landing experience. I find this the best part of instructing - and I don't get the time to do alot these days - well that and wing-overs, dynamic stalling with full power and full flap, cloud dodging, ultra-low level, early turns into the circuit at 50'....you know the stuff.:ok:

BubbaMc
13th Jun 2009, 05:37
Just get them to fly level a metre or so above the runway. Then power off and hold off as required.

David Horn
19th Jun 2009, 17:42
The thing that helped it click for me was an instructor allowing me to do a low approach down the length of the runway, just holding the aeroplane in ground effect.

He did one first with me observing and getting a good mental picture of exactly what things should look like in the hold-off, then I tried it. Landings just made sense after that.

Of course, we did have a 13,000 ft runway to play with but I can't see why this technique wouldn't work anywhere.

darn
19th Jun 2009, 20:21
David - good idea. I might give that a go, we have a colossal runway where I'm at too, not sure what ATC will think of it though!

Thanks to all the other guys and gals for your tips, much appreciated!

LaoWei
20th Jun 2009, 01:39
What I teach my students is they need to be patient, let the airplane land when it is ready and not force it onto the runway. Also they have to work hard for a good landing, they just can't level off and let the airplane land flat. Their focal point is critical, they have to be looking about half way down the runway. After they roundout (or level off above the runway) they need to be patient and wait. If they start to flare before the airplane begins to descend, they will balloon (begin to climb). Once the aircraft begins to lose altitude, they need to stop the altitude loss by increasing pitch (flaring). Too much pitch they climb, not enough they continue to descend. They have to find the right amount of back pressure to use, by trial and error, to hold the current altitude. This process is repeated over and over until the airplane touches down.

I show them that their altitude profile looks like going down stairs. Level off, sink, stop the sink, sink, stop the sink.... The pitch gradually increases during this process. Once they can do this, everything else will just start to come naturally. Of course rudder and aileron application will have to be added as necessary. I'm only addressing the pitch aspect of landing here.

So it comes down to patience, timing, and determining how much back pressure to use. Some instructors will have the student "pump" the yoke or stick back and forth continually to teach the right amount of pressure to use for pitch control.

funfly
23rd Jun 2009, 08:24
The key to me was when I realised that the trick is to try not to land - keep slowly pulling back to keep it off the deck as long as you can.


Edited to comment that this does not work if you are 10 feet above the runway!!

Big Pistons Forever
23rd Jun 2009, 15:38
I found getting the student to roll in a little bit of up trim on very short final can be helpfull as it reduces the nose down pitching moment when the throttle is closed at the start of the flare.

Cows getting bigger
23rd Jun 2009, 19:41
How about teaching them not to close the throttle at the start of the flare?

TheChitterneFlyer
23rd Jun 2009, 21:57
Maybe everone should see it from an 'eye height' of 70 feet above the runway; when the mainwheels are actually 35 feet above touchdown! It's all about your 'aiming point' and being on the correct descent profile... for otherwise; it's a big ouch!

TCF

Big Pistons Forever
24th Jun 2009, 02:29
Cows getting bigger

Not sure what your point is.... Do you teach your student to land with approach power :confused:

ReverseFlight
24th Jun 2009, 04:17
Another often used method of persuading students to hold off landing during the flare is to get them to do some flapless approaches and make them fly in ground effect for as long as possible before the main wheels touchdown. Then go back to flapped approaches and it works a treat.

It is equally effective for night as well as day circuits.

Cows getting bigger
24th Jun 2009, 05:36
Big pistons, not quite but I don't teach them to close the throttle at the start of the flare. With your technique you have recognised that the nose will want to pitch down as you cut power - just at the point where you want to pitch the nose up. So, the pilot is having to not only change the picture but also react to a configuration change together with a change of elevator effectiveness (reduction in slipstream). If you're not constrained by having a very short runway, get the student to flare whilst maintaining the approach power setting. The laws of physics will apply and the aircraft will still decelerate and will still descend. Once the aircraft is in the 'level' attitude, then allow the student to gradually reduce power whilst still pitching up. Taking this to the extreme, you can try demonstrating a landing with approach power - it works. As the student becomes more familiar with the picture/technique he/she can modify it such that power is gradually reduced during the flare.

If you use this method you will present the student with more options. The cut power at/before flare takes away one of those options and relies, completely, upon the pilot pitching at the right time with the right rate of change of attitude whilst compensating for a configuration change. If you use the other, every so often the student will get it wrong, cut the power, let the nose drop, over-compensate, balloon ...........

Big Pistons Forever
24th Jun 2009, 16:32
Cow's getting bigger

I started instructing using your method but eventually had more success with having the student close the throttle before the flare. We want to have the aircraft touch down with a nose up attitude. The easiest way IMO to do this is to start the flare at the right speed in the power off condition which will result in a short hold off followed by a firm nose high touchdown. The longer the aircraft spends in the flare the more chance the stude is going to screw things up. I have also found that in the early stages the student is fully engaged managing the pitch attitude in the flare and to ask him/her to simulataneously manage a smooth power reduction is asking too much.

Tinstaafl
24th Jun 2009, 17:53
There's a lot happening - and changing - during the flare & hold-off, with a concomitant effect on the required control inputs. Not only is there a lot happening & changing but the rate that things are happening & changing is also....erm.....changing. To make matters worse the rate of change is also changing as is the effect of any control inputs.

No wonder it's difficult for the poor bloody student to perceive, interpret, decide & react to it all. I'm a firm advocate of limiting flying at this stage to calm or nearly calm weather conditions with a reasonable horizon *and* minimal turbulence. Think very early mornings.... :pukey:

Using as long a runway as you can find, you can help relieve the student's high workload by separating a lot of the tasks over time ie split the roundout, power reduction, hold off, landing & rollout into completely separate items. This will reduce many of the dynamically changing things that would otherwise occur.

First get the the student to transition to flying level over the runway. This will also help you judge his/her judgement about their flare heights & them to learn the control inputs needed to achieve level flight at the correct height over the runway.

Once they're able to fly stabilised S&L over the centreline have them (or even you, if necessary) *gradually* reduce power. Emphasise holding off & keeping straight while this is happening. Eventually the student will be able to get to idle power while still airborne & straight.

Get the student to continue doing more of the same while the speed reduces with the power at idle.

Then focus on control after touchdown etc

VNA Lotus
25th Jun 2009, 12:42
well, I have another technique that I apply, it works well.

During the final I tell my student to maintain a quite "high" speed, I mean above 1.3 Vstall, for example if 60 knots is the 1.3Vs, I tell my student to fly at 70-75 knots. of course if the runway is not limited...

During the briefing I warn my students it is just for training! after that they will maintain the correct speed of course and I explain them why I do that:

My point: In fact if they fly a little bit faster, they will need to control the nose very smoothly, if not the case, the a/c will start climbing right away.
So they learn to make fractions corrections of the attitude before the touch.

after some landings, I tell them to maintain the correct speed, and they always find the flare easier lol Because the learned how to raise the slowly before.

Other advices I add for the flare:

just raise the nose slowly a little bit below the horizon (natural).

an Important point: NEVER raise the nose too high and being unable to see the runway!! too dangerous, I always tell them, you must to see the runway, the centerline. If you raise too high the nose, you will not know if you are aligned properly or if there is an obstacle on the runway (vehicle, animal etc)...

Tmbstory
27th Jun 2009, 06:36
There is lots of good information in the above posts. Try and keep it simple.

Please refer to my post # no:6 in this thread.

Tmb

boltz
28th Jun 2009, 05:29
There are two methods that I use:
#1: Demonstrate the correct hold-off height/attitude and hold it there without touching down for the whole runway. Then get the student to do it. I used this when the student is inconsistent with his/her hold-off height/attitude.
#2: On final, get the student to use the flight controls as you to control the power. This way the whole approach/landing will be more stable/smoother because the student doesn't have to worry about power or speed. I also teach attitude = aiming point, power = speed. Do a couple of approaches like this and they'll land the aircraft with ease. Try it next time your in the aircraft and you'll be surprised.

And like other people have said, make sure the student is looking at the end of the runway not the threshold as he/she flares.