General convention is to plan on nil wind. However, the actual landing is predicated on the reported (or forecast) wind.
thats correct, but in this case i cannot follow you gents in regard to reduced margins adding 50% wind to the vref on actual condintions and planned with zero wind for a given runway.
to keep it simple : having an Vref of 100 kt IAS and zero wind gives you a GS of 100 kt on final ( neglegating the IAS-TAS on that small altitudes) . this will result on a given runway xx landing distance and xx margins to runway end.
having 10 kt headwind and adding 50% of it to the Vref will result in Vapp of 105 kt IAS and just 95 kt GS and this will reduce landing distance and improve the margins- the runway has the same lengtht with or without wind .
so you a ) go slower above the ground ab b) have bigger margins for landing on actual vs planned conditions since its common knowledge that headwind reduces landing distance.
what i am missing ?
best regards !