Judging height in the hold-off
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WOW, when I posted this question I never expected such FANTASTIC feedback and discussions ! Thanks everyone, this is surely a very, very informative discussion !
Chuck, I would be very interesting in your article
Chuck, I would be very interesting in your article
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during the landing including the flare and hold off is accomplished by what you see, not what you feel
Maybe "getting a feeling for judging the height accurately" would make you happier?
When you drive your car down a highway do you stay in the lane you are in by feel or by sight?
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I will try and describe how I teach correct height judgment for the flare and height judgment after the flare.
First the flare:
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 on final, during the last fifty feet in a small airplane 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.
Note:
Rather than describe to the student what I am seeing I count down the height from fifty feet to the flare and have them memorize what they observe up to and at the flare point, this avoids any misunderstanding of what I am trying to describe. By using this method the student will quickly imprint the picture that she / he is seeing.
Once the flare is started you then look straight ahead down the runway to the point where apparent movement of the runway markers stop.
What is................... " Apparent movement of the runway " ..........
There is a point ahead of the airplane where apparent movement of the runway towards you ceases. This point will change with the speed of the airplane and eye height above the runway.
For light aircraft that approach in the 50 to 70 knot speed envelope the apparent movement of the runway,,, runway marks, will be approximately five hundred feet ahead of the airplane.
That is the distance ahead of the airplane that your center of sight should be aimed at. This will give you the proper picture that will allow you to best judge height.
The reason that this works is 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, this 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 of the nose at the runway still using the same distance ahead that gives the picture that you need. Where apparent movement stops.
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 have an excellent movie that was taken at Airbus Industries during my A320 training and I use it when describing what to look for when determining where the apparent runway movement stops. The beauty of the movie is I can stop it and show the point on the runway where this occurs, then start it up again.
Also the movie is perfect for the flare picture, the A320 approaches at a higher speed than a light aircraft but the picture remains the same when looking at the flare point, it just happens faster. ( oh by the way you don't actually flare an A320 like you do a Bug Smasher but the height judgment is the same. ( aided by the computer voice giving you exact height.
I am willing to keep answering any and all questions about how I teach height and speed judgment, all I wish to do is make flying safer and easier for those who fly for the love of it.
My system works because I have been perfecting it for fifty years and I used to teach crop dusting where if you do not know how to accurately judge height and speed you die.
So if you all want me to keep explaining my method I am willing to type until everyone understands how I do it.
By the way:::
I use a camcorder for all my advanced flight training, when the student fu..s up it is easy to review it right after the flight and explain where it started to go wrong and how to prevent repeating the fu.. up
_________________
The hardest thing about flying is knowing when to say no.
First the flare:
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 on final, during the last fifty feet in a small airplane 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.
Note:
Rather than describe to the student what I am seeing I count down the height from fifty feet to the flare and have them memorize what they observe up to and at the flare point, this avoids any misunderstanding of what I am trying to describe. By using this method the student will quickly imprint the picture that she / he is seeing.
Once the flare is started you then look straight ahead down the runway to the point where apparent movement of the runway markers stop.
What is................... " Apparent movement of the runway " ..........
There is a point ahead of the airplane where apparent movement of the runway towards you ceases. This point will change with the speed of the airplane and eye height above the runway.
For light aircraft that approach in the 50 to 70 knot speed envelope the apparent movement of the runway,,, runway marks, will be approximately five hundred feet ahead of the airplane.
That is the distance ahead of the airplane that your center of sight should be aimed at. This will give you the proper picture that will allow you to best judge height.
The reason that this works is 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, this 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 of the nose at the runway still using the same distance ahead that gives the picture that you need. Where apparent movement stops.
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 have an excellent movie that was taken at Airbus Industries during my A320 training and I use it when describing what to look for when determining where the apparent runway movement stops. The beauty of the movie is I can stop it and show the point on the runway where this occurs, then start it up again.
Also the movie is perfect for the flare picture, the A320 approaches at a higher speed than a light aircraft but the picture remains the same when looking at the flare point, it just happens faster. ( oh by the way you don't actually flare an A320 like you do a Bug Smasher but the height judgment is the same. ( aided by the computer voice giving you exact height.
I am willing to keep answering any and all questions about how I teach height and speed judgment, all I wish to do is make flying safer and easier for those who fly for the love of it.
My system works because I have been perfecting it for fifty years and I used to teach crop dusting where if you do not know how to accurately judge height and speed you die.
So if you all want me to keep explaining my method I am willing to type until everyone understands how I do it.
By the way:::
I use a camcorder for all my advanced flight training, when the student fu..s up it is easy to review it right after the flight and explain where it started to go wrong and how to prevent repeating the fu.. up
_________________
The hardest thing about flying is knowing when to say no.
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Hi Chuck,
If your still out there could you help me a little more on your technique.
Is "the Point where Apparent Movement of the runway Stops " the same as the aim point in the earlier part of the landing ie the point the plane is actually flying to. If so how does that assist height perception ? Is it a "ground rush" perception your looking for? If the PAMS is the same as the aimpoint why does it only move to within 300'-500' and not almost directly under the tyres at touch down? Is the last movement of the PAMS to quick to percieve?
What is your view (no pun intended) on Stick and Rudders technique (the chapter appropriately enough on the landing !) where he talks about "eye level horizon" "relaxed eyes"(moving to take in all the visual information of perspective, masking, relative size etc). The latter being at odds with fixing the view on a point on the runway.
I think height judgement in the flare is crucial. I don't think I am very good at it (I was going to ask if you had any slots available this week but unfortunately realised the commute maybe a bit excessive although I'm sure Vancouver Island must be beautiful !!) I do think that natural ability can be augmented by good structured teaching. Something I think is often (but not always) missing when this area is taught in basic training.
TIM
(PS do you know if your Airbus video is accessible through the internet. Have searched in vain on YouTube.)
If your still out there could you help me a little more on your technique.
Is "the Point where Apparent Movement of the runway Stops " the same as the aim point in the earlier part of the landing ie the point the plane is actually flying to. If so how does that assist height perception ? Is it a "ground rush" perception your looking for? If the PAMS is the same as the aimpoint why does it only move to within 300'-500' and not almost directly under the tyres at touch down? Is the last movement of the PAMS to quick to percieve?
What is your view (no pun intended) on Stick and Rudders technique (the chapter appropriately enough on the landing !) where he talks about "eye level horizon" "relaxed eyes"(moving to take in all the visual information of perspective, masking, relative size etc). The latter being at odds with fixing the view on a point on the runway.
I think height judgement in the flare is crucial. I don't think I am very good at it (I was going to ask if you had any slots available this week but unfortunately realised the commute maybe a bit excessive although I'm sure Vancouver Island must be beautiful !!) I do think that natural ability can be augmented by good structured teaching. Something I think is often (but not always) missing when this area is taught in basic training.
TIM
(PS do you know if your Airbus video is accessible through the internet. Have searched in vain on YouTube.)
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I would like to pick-up on the T&G argument. My experience is that low-houred (or how about early Ex12/13?) student pilots get rather tense with landings, try to fly by numbers and have a tendency to rush. All too often do I sit with a student pilot who hasn't completed his landing before he commences his take-off. This leads to some interesting 'rollers' where the aircraft may be wrongly configured and almost certainly drifting off the centreline.
So, in the early sessions I'm concentrating (or getting the student pilot to concentrate) on landing the aircraft (to be precise, I'm getting him to expect to go-around or land if everything turns out fine). Once he is in the groove, I'll start to load him with more tasks, ultimately leading to T&Gs. But, the chap is now conditioned to alway prioritise with a G/A, Land or T&G in that particular order.
So, in the early sessions I'm concentrating (or getting the student pilot to concentrate) on landing the aircraft (to be precise, I'm getting him to expect to go-around or land if everything turns out fine). Once he is in the groove, I'll start to load him with more tasks, ultimately leading to T&Gs. But, the chap is now conditioned to alway prioritise with a G/A, Land or T&G in that particular order.
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I agree that touch and goes have a place in flight training, though perhaps a place which is more limited than commonly applied. New pilots cannot, and generally should not be expected to change "modes" so completley, so quickly, particularly when it is necessary to maintain control the entire time. As said, something's going to get missed. That's not good learning. It is not ideal to require the use of a checklist prior to takeoff, and then not allow the time required to concentrate on it. That sends a message that it is not important. That said, pilots do have to be aware, and prepared, should an overshoot after touchdown be necessary for some other safety reason. That is why we test to assure that an overshoot (takeoff) is possible in the worst case landing configuration, in case the pilot did not get the aircraft reconfigured, before getting airborne again.
In particular, touch and goes are not ideal for water flying training. Time on the step is important, but time learning how to get on and off the step is equally importnat, and should not be missed, because a touch and go was done instead.
I have seen too many aircraft touch down, only to see all of the flight controls apparently be forgotten as soon as the ground is contcted. In my opinion, if an aircraft is moving through the air, it should be being flown by its pilot. The fact that the aircraft is on the ground, does not absolve the pilot of the responsibility of assuring that it is moving through the air as intended. Again, a practice opportunity lost in touch and goes. Touch and goes should be stop and goes, where runway length and traffic permit, and otherwise scattered into training, rather than being a mainstay.
Just my opinion...
In particular, touch and goes are not ideal for water flying training. Time on the step is important, but time learning how to get on and off the step is equally importnat, and should not be missed, because a touch and go was done instead.
I have seen too many aircraft touch down, only to see all of the flight controls apparently be forgotten as soon as the ground is contcted. In my opinion, if an aircraft is moving through the air, it should be being flown by its pilot. The fact that the aircraft is on the ground, does not absolve the pilot of the responsibility of assuring that it is moving through the air as intended. Again, a practice opportunity lost in touch and goes. Touch and goes should be stop and goes, where runway length and traffic permit, and otherwise scattered into training, rather than being a mainstay.
Just my opinion...
Many good words said previously.
To answer the question: I know exactly how high I am when I hear the tailwheel brushing through the grass, then add a bit of spoiler to bring down the main. There can be years between such landings
Flying powered a/c, I prefer something steeper than the 3 degree ILS angle beloved of many flight schools. The impact point then becomes apparent and self preservation instincts generally lead to a flare at the right time: i.e. when the impact point blossoms, usually at a point when grass blades or hard surface details become visible.
Peripheral vision and transferring focus to the end of the runway has already been well discussed, but I find myself making sideways glances to the runway surface.
To answer the question: I know exactly how high I am when I hear the tailwheel brushing through the grass, then add a bit of spoiler to bring down the main. There can be years between such landings
Flying powered a/c, I prefer something steeper than the 3 degree ILS angle beloved of many flight schools. The impact point then becomes apparent and self preservation instincts generally lead to a flare at the right time: i.e. when the impact point blossoms, usually at a point when grass blades or hard surface details become visible.
Peripheral vision and transferring focus to the end of the runway has already been well discussed, but I find myself making sideways glances to the runway surface.
I have been flying for about 180 hours on Cessna 172 mostly and some hours on Piper Archer 181.
I am fairly confident that I land well on most occasions, consistently. The last circuit training flight I did, I tried to concentrate on those final few seconds in the hold-off, just before you touch the runway. I realised that I don't know exactly how high I am from the surface of the runway ... I can "feel" that I should be close, but I never really can tell EXACTLY how high I am and whether a touchdown is going to be a greaser or whether I am still going to be 1 foot or so above the runway when it stalls (lands).
So, I am curious. How many pilots (light aircraft) can tell EXACTLY how high they are from the runway surface those final moments before touchdown, or is it really a "feel" thing, like with me most of the time ?
And yes, I have been tought to look ahead of the aircraft, slightly to the left, to the point down the runway where it appears to be stationary. I still can never tell exactly how high I am, except for anticipating and "feeling" when it feels that I am about to touch down.
I am fairly confident that I land well on most occasions, consistently. The last circuit training flight I did, I tried to concentrate on those final few seconds in the hold-off, just before you touch the runway. I realised that I don't know exactly how high I am from the surface of the runway ... I can "feel" that I should be close, but I never really can tell EXACTLY how high I am and whether a touchdown is going to be a greaser or whether I am still going to be 1 foot or so above the runway when it stalls (lands).
So, I am curious. How many pilots (light aircraft) can tell EXACTLY how high they are from the runway surface those final moments before touchdown, or is it really a "feel" thing, like with me most of the time ?
And yes, I have been tought to look ahead of the aircraft, slightly to the left, to the point down the runway where it appears to be stationary. I still can never tell exactly how high I am, except for anticipating and "feeling" when it feels that I am about to touch down.
There is a myth that every landing is supposed to be a barely perceptable brush of the tyres on the runway. IMO "good" landings mean the touchdown is at the end of a stabilized approach (ie the nose is not nodding up and down) flown at a constant, correct for the conditions airspeed, with the touchdown occuring at the preselected point on the runway in a nose high attitude (nose gear aircraft).
Under many conditions a firm controlled touchdown is preferable to a "greaser" ( eg short fields or gusty winds) and IMO represents better airmanship.
In my experience instructing the old adage "good approaches = good landings" is very true. Low time pilots who have trouble judging the flare are invariably not flying consistant on speed constant flight path approaches and
fixing the approach to the runway will also fix problems judging the flare and having a smooth hold off ( ie no porposing in the flare or an excessively high hold off height) prior to touchdown
My advice is go do some circuits and work at flying the final as a constant flight path to the flare point with the aircraft in trim and the speed held to + - 2 knots. I bet your landings will instantly improve
