Originally Posted by
Check Airman
Well my point is that you do know which one is correct. The PFD Vls is correct
------
Devil's advocate. What if today's one of the days when it's -3?
Now me playing Robin to devil's advocate: If on a given day, the displayed Vapp is Vls +5 AND at the same time the FAC is under-reading by 3 knots: should we not add +3 to cover the eventuality, making it VLS+8 at least at all times?
Will you also acknowledge that Airbus went to certain lengths and already adopted a modification for PFD, where the VLS is displayed based on FMS&LDS data, so the habit of fiddling with Vapp is eradicated systematically?
Are we really smarter here than the OEM engineers and standards technical pilots,
as well as the financial controller who signed for the investment needed to develop the mod?
We didn't have any short/long landing technique.
Post a picture / coordinates of your next (MLG) touchdown, dare? Or at least your most frequented landing runway.
As I stated before, if the runway length is limiting, I'm happy to let the Vapp sit on top of Vls.
That awfully sounds lot like a different technique for a short LDA, pardon my french.
Here's the point: if you are willing to fly closer to displayed Vls on a limiting rwy (please do say what lenght is limiting for you - I mean what distance), why get all excited with Vls +4 on a long runway? Why not get a practice of flaring from Vls +3: at least we'd train a bit and stand lesser chances of screwing up when shooting into a limiting LDA with Vapp sitting atop VLS, hm?
There are some seriously good points in the thread.
- measure with a micrometre, cut with an axe - what's the point (my language's own version: a precise calculation of inaccurate values)
- if suspect of the weight, work the work and brief it with S-speed data, do not start playing smart only after landing flaps is gets extended.
- the debate is academic for a day's flight, but at a grass-root systematic level quite relevant
- the certified approach speed is Vref. The additions go on top for a reason.
- sloppy flying and lazy thinking is not the target state for a professional