I think I got a "preliminary conclusion " ( susceptible of debating, of course ) :
Thank you NZScion for the link. It confirms the one sent by ShoreGuy ( I guess it is all ICAOīs )
For as to VASIS, it is clear that it DOES contemplate a solution for the higher-lower cockpits ref. pt. of view, and the theory of the PARALLEL glideslopes I was talking about before seems to be demonstrated in fig. 5-12 of such doc.
As for our topic, the PAPI, ( according to the same doc. ) it DOES seem to work ONLY for the type of aircrafts the aerodrome has decided is going to operate with.
The recommendation is to place the lights at a DISTANCE where the wheel clearance over the threshold of THE MOST DEMANDING A/C and MOST REGULARLY using the RWY is ensured.
Nevertheless, when this height is not met, then a "
reduced wheel clearance is accepted".( table 5-2 on pg. 100 ).
Looking out for my A/Cīs eye-to-wheel dist. ( 34ī), I come up suddenly with another info I wasnīt looking for : I have a Minimum wheel clearance at the threshold!! and Guess what. Itīs 20ī !!!
20ī= 6 m.
Now take a look to the 5-2 table again, and there you got it; I find myself in the reduced wheel clr. height column 3 !
Therefore, airports who donīt consider a widebody as a regular traffic MAY NOT have placed the PAPI lights where they need it to ovfly the threshold at 50ī, but, I guess we oughta think they have ALWAYS placed them in such position that AT LEAST the min. WCH is ensured.
CONCLUDING :
On a PAPI,
FLY THE 2W-2R glideslope no matter what a/c youīre coming in with, You have minnimum ( although sometimes reduced ) wheel clearance with a widebody.
Any rebates ?....
( Man, come to think all these years I have been flying close to 50' HAT, and have thought all the calcīs. were done taking
that into account, and I realize now that every time I make a visual, I might be crossing the thr. below half the dist. I thought I was at some smaller airports ).
Thanx all of you for the valuable help.
