On Sun, 5 Jun 2005 10:53:40 -0700, "Bob Gardner"
wrote:

Gotta wonder why the protected airspace on the non-PT side is 1.4 miles wide
all the way out to the maximum distance. If flying on the black line is a
regulatory requirement, why not just protect the turn area alone?

Maybe to take into account and give some protection for VOR, onboard
equipment, and operator error? At the far end of the maximum 10NM
circle for a standard procedure turn distance, if the VOR itself was
drifted say 4 degrees and then your aircraft was off 4 degrees and
then you didn't have the exact number dialed in and so were off 1
degree to begin with... So say there is a combined error of 9 degrees
off, you're already 1.1NM off the 'desired' track at about 7nm, right,
but still would have a centered needle. Even with a perfect needle
(say glass cockpit for the VOR OBS setting and autopilot handling
accuracy) the VOR approach to 6B6 puts you at/over (I forget the exact
number right now) around 1NM to the right of the airport at the MAP.
It was quite interesting doing it under the hood, having the needle
centered the whole time, and then playing 'find the airport' when I
pulled up the hood.