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Old June 4th 05, 09:34 AM
Peter Duniho
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"Yossarian" wrote in message
7.142...
AIM 5-4-9 a. The procedure turn or hold in lieu of procedure turn is a
required maneuver.


I'm going to have to equivocate on the phrase "is a required maneuver".
You'll note that the very first sentence reads (in part) "A procedure turn
is the maneuver prescribed when it is necessary to perform a course
reversal..."

The AIM is, of course, not regulatory. So if it claims that the procedure
turn is a required maneuver, it must be referring to some other regulation
somewhere. Of course, the AIM doesn't actually provide a cross-reference,
so we don't know what regulation they have in mind.

I'm going to go out on a limb here and suggest that the "is a required
maneuver" phrase applies only when "it is necessary to perform a course
reversal". IMHO, any other interpretation is absurd. They are specifically
telling you the procedure turn exists for the sole purpose of reversing
course; why would it be required to fly the procedure turn when you don't
need to reverse course?

Executing a procedure turn in the example you give requires more
maneuvering, more time, and provides no real safety improvement (and in
fact, could lead to a pilot inadvertently leaving the protected airspace,
and/or flying below minimum safe altitudes for the approach and surrounding
area).

Now, all that said, I think I've already implied I'm not an expert in this
area. I certainly don't KNOW that I'm right. But I'm definitely not
convinced I'm wrong either.

[...] I'm betting not many
people fly the procedure turn coming in from WILMA.


true on that last sentence, but it's because you always get vectors.


I will further bet that's not the ENTIRE reason.

Where's Wally when you need him?

Actually, he might not be as helpful (at least, to me) as I might have
thought. Here's an interesting article that supports your interpretation of
the rules:
http://cf.alpa.org/internet/alp/2000/jansafety.htm
However, IMHO it's an obviously absurd way to interpret the rules. It
doesn't address your example directly, since the inbound course is nearly
aligned with the final approach course. But it seems patently obvious to me
that flying the entire procedure turn in this case is just plain wrong; it
achieves nothing except to waste time and put the airplane farther away from
a proper approach course.

Roberts is, as the article shows, a firm believer that without radar vectors
and/or other criteria mentioned in the AIM, the procedure turn is mandatory.
The justification appears to be that no matter how closely aligned with the
final approach course you are, if you're not EXACTLY aligned with it, you
have to turn around and "try again".

My understanding is that, if ever there was an expert, Roberts is it. But
it's still unclear to me where his interpretation comes from. It also still
seems to fly in the face of sensibility.

Another well-respected aviation educator and writer, Gene Whitt, suggests
that it is the pilot's discretion to fly the procedure turn or not (though,
he also has no references). From his web page:
http://www.whittsflying.com/Page7.38...Procedures.htm

If ATC does not specifically state that you will be given
radar vectors, you as PIC can decide if a procedure turn
is required.

Note that I am not suggesting that straight-in always implies no need to fly
the procedure turn. As Jose noted, there may also be an altitude issue.
I'm simply talking about the example you provided, in which the transition
altitude is already low enough to allow for entry over the FAF at a normal
approach inbound altitude, and where the maneuvering required in order to
complete the procedure turn is at least as complex (and thus potentially
dangerous) as that required to simply proceed inbound on the approach from
the transition route.

Pete