Logistics of a Portkey

[justcarol67]

Saitaina asked:
> 
<snip>
> 
> > 1.  If one were traveling on a
> > broomstick and used a portkey that was
> > activated to touch, would he disappear
> > from that situation instantly (like
> > apparition) or fade away or what?
<snip>
4.  Do you have to be on tera firma to use it?  (or could you be airborne)

Dina responded:
> I'm under the impression motion is very limited--estimating that
breaking contact with an active portkey is considered impossible or
could cause 'splinching'.  Being on a broom while using a portkey
would be dangerous since you'd lose control before (i.e. during the
'pull') and after transport.
<snip>
 
> Being fairly still and on the ground would be the safest but I'd
think it possible, if not dangerous, to be on a broom while using a
portkey.

Carol notes:
While I can't provide any information regarding logistics, I agree
with Dina that using a portkey while riding on a broom would be very
dangerous. Moreover, it would be, IMO, unnecessary and illogical, like
apparating using Floo Powder. Brooms and portkeys are both forms of
transportation, the portkey being much faster, of course. I can't see
any reason to use both at the same time. If you had a portkey, you
wouldn't need a broom.

Carol