tag alias: vapor trail -> contrail

tag alias: vapor trail -> contrail

reason: pretty much the same. and maybe if the alias pushes through, we can delete the vapor trail wiki. it appears there's some sort of vandal(?)

EDIT: bump.

To me, a vapor trail comes from engine exhaust condensing, while a contrail comes from the wing surface or tip due to air condensation during a stall. Though I see Wikipedia combines the two.

I've always thought of them as synonymous, but I'm no expert in this area.

Contrail is short for condensation trail, which can come either from the wings or the engines. So I'd argue both tags should be aliased to condensation_trail.

Vapor trail is a misnomer since you can't actually see the vapor, you only see it after it has condensed (i.e. when it's not vapor anymore but an aerosol of liquid water droplets).

Aliased both to condensation_trail

i think these were unintentionally left out (is the first removal step necessary btw?):

remove alias contrails -> contrail
create alias contrails -> condensation_trail
create alias contrail -> condensation_trail

I guess once again the aliases didn't take because a contradictory one was already in place. Fixed.

ok, thanks!