Oracle427 wrote: ↑14 Sep 2019, 22:54
I disagree that the pilot's groundspeed will dictate when and not where. A well trained and proficient pilot can rather precisely manage their touchdown point no matter the groundspeed.
Returning to the original condition, engine at idle (gliding flight)...if you chop the throttle on speed (proper approach air speed), and at some given altitude, what remains constant regardless of the steady wind (and hence ground speed) is the time you have remaining before you smack the wheels down, assuming similar control technique. What in turn depends on the wind, of course, is the remaining ground
distance covered during that flare maneuver. I think this is rather not debatable point, right? Of course, if you want to target a precise touchdown point, you need to take this into account in timing of your flare and cutting the power. So, you end up taking the wind speed (and hence again, the ground speed) into account. Right?
Oracle427 wrote: ↑14 Sep 2019, 22:48
If you are actually saying that the pilot should maintain the correct airspeed and not deviate from the correct airspeed on their approach regardless of what groundspeed they are making then I have no issue with what is being said here.
Are you saying that adding the wind corrections to the approach reference speeds they have been doing for decades is complete rubbish? They should stop doing that? Probably thousands of approaches and landings every day add half of the steady head wind component plus the full gust increment, cumulatively +5 knots minimum and +20 knots maximum, to the reference approach speed, which in turn is directly based on stall speed. Other similar "formulae" exist. You do know the reasoning behind wind corrections to final approach speeds, right? Only thing I'm stating perhaps unconventionally here is using word ground speed instead of wind speed.
Oracle427 wrote: ↑14 Sep 2019, 22:48
If the aircraft flies an approach at the proper airspeed (not any faster or slower) it doesn't matter what the winds are doing or what the groundspeed is. When the aircraft airspeed decreases below it's landing configuration 1G stall speed in a normal landing configuration. The aircraft *WILL* stall and it will not be able to bounce, skip or anything assuming the pilot maintains directional control and landed from at a normal height. The aircraft is simply is unable to generate sufficient lift to fly once it is stalled. If the pilot comes in with excess airspeed and touches down before bleeding off that airspeed, I can guarantee that they will bounce and skip or whatever else, because the aircraft has excess airspeed to lose before stalling.
What about aircraft that are not stall-landed? Such as some twins, many (most?) gliders, fast stuff, et cetera?
By saying it doesn't matter what the winds are doing, do you say that if you lose ten knots of headwind you
don't lose ten knots of (true) airspeed unless you make that back up again, either by increasing engine power (if installed), or by sinking slightly on the approach? I guess that's not what you're saying, no. Would it not be more efficient to anticipate,
if able, this loss, and carry those extra knots indicated with you to shed them off when penetrating the wind gradient?
If I'm flying very slow aircraft, with nominal approach speed of say 85 km/h, don't you think that a prompt loss of 10 knots, which is 22 % of my approach speed, at around treetops height would put me uncomfortably close to running out of luck for the day? Would it not be a good idea to make the approach speed like 95 km/h when I anticipate such conditions? Note, this is not to be kept as a threshold speed, so when you lose your extra knots to the wind gradient, you don't want to regain them anymore!
I'm talking about very conventional thinking here, after all. Nowhere have I said, not would I ever say, that ground speed as a number should be anyone's
primary flying reference for much anything except navigation and hovering a helicopter, hopefully for obvious reasons. What I'm simply saying is that its importance as a reference to airplane's inertial speed is often forgotten or not understood, and that it can and does provide the only cue available to the actual wind component at the airplane's current position.
Edit: I do appreciate you put strong emphasis on avoiding overruns on short runways. For my kind of real physical world flying I used to do, that was basically not a factor. Instead, landing short really was, and my home airfield sometimes was notorious for its difficult wind conditions. So, different people come from different backgrounds, have different educations and experiences - and hence different points-of-view, priorities and opinions!
-Esa