The following is how I teach and describe the approach and height judgement for the flare and height judgement after the flare.
First the approach from two hundred feet above the landing to the flare point::
I use a definable point on the runway as the flare point, usually the first big hash marks and runway numbers. This is the aim point for the flare on final, during the last fifty feet the aim point will start to grow in size and also appear to spread out in your vision, at about twenty feet the picture will become quite clear that you are about to fly into the runway. It is at this point that I start the flare with most light aircraft.
Rather than describe to the student what I am seeing I have them memorise what they observe during the approach by what they see as I call out each different height above the surface.
By using this method the student will quickly imprint the picture that she / he is seeing as they get closer and closer to the point they are aiming for.
( The method I use is having them memorise the closing rate and height above the flare point and touch down as I verbally call the the height they are passing.
Starting at two hundred feet, I verbally say one hundred feet, then fifty feet, then twenty five feet then at twenty feet " start the flare ".
Once established in the flare the height call outs become more frequent - fifteen , ten feet and from that height I call the closure by the foot,,, ten, nine , eight, seven, six, five, four, three, two, one. )
Once the flare is started you then look straight ahead down the runway to the point where apparent movement of the runway markers towards you stops.
What is................... " Apparent movement of the runway towards you stops " ..........
There is a point ahead of the airplane where the apparent movement of the runway markers towards you will cease to move towards you, the closer to your position you look the faster the apparent movement becomes, the further away you look the slower this movement towards you becomes until it stops. This point will change with the speed of the airplane. This is what I describe as " The point at which apparent movement ceases. "
For small training airplanes that approach in the 50 to 70 knot speed envelope the point at which apparent movement of the runway marks towards you ceases will be approximately five hundred feet ahead of the airplane.
That is the distance ahead of the airplane that your centre of sight should be aimed at. This will give you the best picture that will allow you to best judge height looking to far ahead degrades your ability to judge height.
You can see the runway get closer in your peripheral vision as the runway movement close to the airplane changes. Also you can see the far end of the runway in the top of your peripheral vision, which is your attitude guide that allows you to change the attitude as speed and lift decays.
Ideally the airplane should contact the runway in the attitude that the stall occurs. ( Except wheel landings in taildraggers. )
If the nose blocks out your view ahead as you increase the nose up attitude during the hold off all you need do is move your head and sight line to the side and look along the side nose at the runway still using the same distance ahead that gives the picture you need.
Note as you slow down the runway movement picture moves progressively closer. ( About three to five hundred feet ahead is just about right at touch down.
I am willing to keep answering any and all questions about how I teach height and speed judgement, all I wish to do is make flying safer and easier for those who fly for the love of it.
This system works for me because I have been using it for many decades. I used to teach crop dusting where if you do not know how to accurately judge height and closure rate with the surface you can die in the crash into the ground.
By the way:::
I used a camcorder for all my advanced flight training, when the student starts to lose the picture during the training it is easy to review it right after the flight by stopping the video recording and asking the student where they nwere looking and what did they see at that exact time.
and explain where it started to go wrong and explain to them how to correct as soon as the picture changes.
(( The hardest thing about flying is knowing when to say no. ))