Established on the approach - Checkride question

Greg Esres wrote:

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.

Your points are all right on. Having said that, this thread demonstrates
that, 29 years after TWA 514, both pilots and controllers do not fully
understand this stuff. The clearance for that NDB approach with "until
established" is a "setup" by ATC; albeit from lack of controller
understanding. Over the years since the TWA 514 crash the controller's
handbook has had many layers of "inner tube" patches on the area of radar
vectors to approach procedures. The only correct clearance for such a
vector to the PT area, would be for the controller to withhold approach
clearance, using MVAs, until the aircraft is within 10 miles of the PT
fix. But, this is simply not taught to controllers. The burden for this
one should be on ATC, not the pilot.

Greg Esres writes:

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.

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.

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


Thanks for the info,


David

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.

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

"Greg Esres" wrote in message
...

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.


What approach is that?

"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.

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.

"Ron Natalie" writes:

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.

As I mentioned in the bit you quoted, it's different up north -- in
Canada, MSA *is* operational. If you are cleared for an approach and
not given an explict altitude restriction, you are automatically
allowed to descend to the lowest of the following (see RAC 9.3 in the
Canadian AIP):

(a) MEA

(b) published transition or feeder altitude

(c) MSA

(d) 100 nm safe altitude

(e) if nothing else applies, 1000 ft above the highest obstacle within
5 nm (1500 ft or 2000 ft in mountainous areas)

Typically, when you're being vectored and then are cleared for an
approach before you're inside the protected area, MSA will be the
winner (assuming that you're within 25 nm of the IAF) -- descending to
MSA was a standard part of almost every practice approach during my
IFR training, especially the full-procedure ones.


All the best,


David