John, always appreciate your answers!
but one had better have a very good reason not to have done so if it all turns to custard ... noting that there is no requirement to achieve the landing within that distance .. only that the factor should be present .. the actual landing is expected to end up somewhere within the pad section of the scheduled distance.
So, if I understand correctly, the pad you mention is that, in line operations (and not a prescribed factor) we should use some distance that is between the 60% and the runway end?
As for misd-agin, perhaps I wasn't clear in not putting a question mark.
My question is, do we as pilots have to cross the runway threshold at Vref? Is that mandatory?
I mean, I've just read safetypee links on certification and what john said makes sense, even though they always mention crossing the threshold at Vref, period.
What I know it's common practice about the wind correction for the Vap, is a minimum of 5kts, so Vref + 5kts = Vap, always, unless the headwind component is greater than 10kts.
The speed correction should be half the headwind component, and also we should add the gust factor. But the Vap should not be more than Vref + 20kts.
With these in mind, and these corrections with at least + 5kts, should we reduce from Vap from Vref somewhere before crossing the threshold, or just use this wind correction, for a good performance's sake.
And yes, ducking under is a concern, which is one of the reasons of this post.
I've seen a video where I assume it's a test pilot landing, because of the abrupt flare very near the ground. I begin to question if the certification is just so that the manufacturer is demonstrating that the airplane can perform adequately, but as there is almost no margins involved, real world landings would never perform as the certification landing requirement.
I'm gonna look for more of these videos.
I just wanted to clear that. I was assuming that all pilots should perform exactly, or better, as the requirement dictates.
It seems to be just the opposite?
Maybe landing performance requirements are not minimum limits, but maximum conservative limits that it's difficult to duplicate, but since there is 40% of a runway to be used, actual operations don't neet to do it? If so, it would be the opposite of takeoff performance where everything's assumed to fail in a worst case scenario, but normally everything performs much better than the requirements.