Established on the approach - Checkride question

If you're on the final approach course and inside the PT limits...
why not?

That's fine, but my point is that the 10 nm is given to you on the
profile view, not the 10 nm ring, which has nothing to do with the PT.

Trivial distinction?

I don't think so. We had an approach that had no PT, yet some
instructors were teaching that an a/c could descend within 10 nm of
our FAF, because of the 10 nm ring.

It's a little different here, because MSA is operational -- we have
an altitude we can descend to as soon as we're within 25 nm.

We're not talking about MSAs, we're talking about the 10 nm ring
around the approach that signifies that the included area is to scale.
There is no associated altitude with this ring, so some pilots assume
that it means the PT altitude. It doesn't.

The MSA is a 25 nm ring and it will provide obstacle protection; the
10 nm ring doesn't do that.

I don't know what Canadian charts look like.

(Note that you snipped out the part where I said I'd call and check
what they actually wanted.)

My point is that it doesn't matter what they wanted.

We had a local approach where we often got vectored to a point on the
extended centerline of the final approach course, but outside the
point where the approach started. The published altitude was 2,000
feet, but we were vectored at 2,500. ATC *wanted* us to descend
immediately on intercepting the localizer, but the approach simply did
not authorize that.

If ATC wanted us at 2,000, then it was their responsibility to assign
that altitude, because only then are they providing obstacle
protection. If a pilot allows himself to be intimidated down to an
unpublished altitude, then there is no obstacle protection being
provided by anyone, and the pilot is in violation of Part 97.

"David Megginson" wrote in message ...


It's a little different here, because MSA is operational -- we have an
altitude we can descend to as soon as we're within 25 nm.

The MSA is for emergency use only. You shouldn't be relying on it for normal
operations.

"Ron Natalie" wrote in message m...

"David Megginson" wrote in message ...


It's a little different here, because MSA is operational -- we have an
altitude we can descend to as soon as we're within 25 nm.

The MSA is for emergency use only. You shouldn't be relying on it for normal
operations.

Oops, didn't recognize you were talking about Canada first...

Canada, Ron, Dave is in Canada.

Bob Gardner

"Ron Natalie" wrote in message
m...

"David Megginson" wrote in message
...


It's a little different here, because MSA is operational -- we have an
altitude we can descend to as soon as we're within 25 nm.

The MSA is for emergency use only. You shouldn't be relying on it for
normal
operations.

"Greg Esres" wrote in message
...
Is it well-defined where the approach segment begins when you're
vectored for SHN NDB-A?

Yes, in theory. ;-) You're on the final approach segment where the
initial segment intersects the final approach course at (or within)
the 10 nm limit stated in the chart.

I see why it's a sensible practice to construe it that way, but is it
officially defined that way somewhere?

--Gary

So as a practical matter, assuming you are able to figure out the misleading
nature of the clearance, what would you do?

I'm thinking that the controller hasn't technically give me anything I can't
fly yet, it's just that I would like to be cleared lower outside of the FAF
(before established). So I would accept the clearance "123Foxtrot cleared
descend 2000". (I have never flown an NDB approach so bear with me here)
Once I had established myself on a course of 232 to the NDB, I would say
"123Foxtrot 2000 request descent 1400feet" The controller would either
reply "123Foxtrot cleared to descend 1400" or "123Foxtrot, radar contact
lost, maintain 2000 until established" I would respond with "123F
maintaining 2000, will report crossing the NDB".

I guess a third option would be "123F, you are cleared to descend once
established".....in which case, see last sentence above.

"Greg Esres" wrote in message
...
I'd guess that you were OK to descend as soon as you intercepted the
inbound course,

Argh! No! The PILOT must know when he's established and within the
protected area. All you've intercepted is a navaid, not a segment of
the approach, until you've reached the start of that segment.

they intend for me to follow any altitude instructions as soon as
I'm on the course, even if I won't be inside PT limits for another 10
minutes or more.

What ATC intends is irrelevant. If they want you at the published
altitude before you reached the point where that altitude applies,
then they're got to clear you down to it, using their MVAs.

Failure to understand this concept has killed some people in the past,
including at least 1 airliner, TWA 514.

See the AOPA article:

http://www.aopa.org/asf/asfarticles/sp9806.html

Ron Natalie wrote:

The MSA is for emergency use only. You shouldn't be relying on it for normal
operations.

True for the U.S. But, MSAs are operational altitudes for much of the world, which I believe
includes Canada.

"Gary L. Drescher" wrote:

"Greg Esres" wrote in message
...
Is it well-defined where the approach segment begins when you're
vectored for SHN NDB-A?

Yes, in theory. ;-) You're on the final approach segment where the
initial segment intersects the final approach course at (or within)
the 10 nm limit stated in the chart.

I see why it's a sensible practice to construe it that way, but is it
officially defined that way somewhere?



On the FAR Part 97 form for the approach. It says "remain within 10
miles." Where there is no segment prior to that, the procedure turn
initial approach segment begins at 10 miles from the PT fix. If normally
ends at that limit, but when vectored to "final" it begins at that
point. Same published-segment airspace boundary in either case.

Greg Esres writes:

I don't know what Canadian charts look like.

Pretty similar.

If ATC wanted us at 2,000, then it was their responsibility to
assign that altitude, because only then are they providing obstacle
protection. If a pilot allows himself to be intimidated down to an
unpublished altitude, then there is no obstacle protection being
provided by anyone, and the pilot is in violation of Part 97.

That's a good point. It looks like this might be a bit of a hornet's
nest of pilot/controller confusion. My instrument rating is still
fairly new, but when I'm being vectored far back (beyond PT limits),
the instruction I get is usually something like "on interception,
descend to ..." rather than "when established on the approach,
descend to ...". That's less ambiguous.


All the best,


David