When to descend

On 10/9/2007 1:20 PM, Steven P. McNicoll wrote the following:
>>
>
> He doesn't say whether this is an actual clearance received or a
> hypothetical scenario. The book phraseology would be, "Cleared to UDUZI,
> maintain four thousand until entering the TAA, cleared RNAV runway niner
> left approach." If he's already crossed the TAA boundary the clearance
> would be just, "Cleared RNAV runway niner left approach."
>
>
"Cleared direct UDUZI, maintain 4000' until established, cleared RNAV 9L
approach." sounds like a lot of clearances I have received. Possibly not by the
book verbiage, but real world IMHO.

Why would you read anything into it? I'm not being argumentative; I just don't
understand why you would not "maintain 4000' until established" and at that
point begin to descend. Or, if you didn't like the profile, get back to ATC and
"request lower."

It could be that ATC had crossing traffic at 3000' -- no?

>don't have to request lower from ATC, clearance for the approach
>authorizes me to descend to 2700 at the TAA boundary.


I'm with Mitty on this one. AIM Section 5-4-5.d.4(b) Says:

"Pilots entering the TAA and cleared by air traffic control, are
expected to proceed directly to the IAF associated with that area of
the TAA at the altitude depicted, unless otherwise cleared by air
traffic control."

If the clearance was indeed "...maintain 4000 until established" that
would fit the "..unless otherwise cleared by air traffic control"
clause.

To put this to a test, ask yourself when would you report established
on the approach if asked by ATC to ".. report established on the
approach"? My answer would be when I'm on one of the depicted
portions of the approach and not the TAA.

I guess one could argue that the TAA is a depicted portion of the
approach but I can't find any official publication pointing to that
fact.

"Dane Spearing" <dane@rescomp.stanford.edu> wrote in message
news:feh21s$t1v$1@news.Stanford.EDU...
>
> Hmmmmm....I'm not sure I buy this. The clearance stated "...maintain
> 4000'
> *until established*..." which to me says that I'm to remain at 4000' until
> I am on a *charted* section of the approach. Simply being in the TAA
> does not mean I'm on a charted section of the approach. For this
> clearance,
> I would say I'm on a charted section of the approach after crossing the
> IAF
> (UDUZI). I would not descend below 4000' until after crossing UDUZI, and
> then I would descent to 2000' as depicted. Or am I being too conservative
> here?
>

TAAs are published portions of the approach, when you cross the TAA boundary
you're *established* on the approach.

Mitty wrote:

>
>
> On 10/9/2007 1:20 PM, Steven P. McNicoll wrote the following:
>
>>>
>>
>> He doesn't say whether this is an actual clearance received or a
>> hypothetical scenario. The book phraseology would be, "Cleared to UDUZI,
>> maintain four thousand until entering the TAA, cleared RNAV runway niner
>> left approach." If he's already crossed the TAA boundary the clearance
>> would be just, "Cleared RNAV runway niner left approach."
>>
>>
> "Cleared direct UDUZI, maintain 4000' until established, cleared RNAV 9L
> approach." sounds like a lot of clearances I have received. Possibly
> not by the book verbiage, but real world IMHO.
>
> Why would you read anything into it? I'm not being argumentative; I
> just don't understand why you would not "maintain 4000' until
> established" and at that point begin to descend. Or, if you didn't like
> the profile, get back to ATC and "request lower."
>
> It could be that ATC had crossing traffic at 3000' -- no?
You are established when you enter the TAA.

gman wrote:

>>don't have to request lower from ATC, clearance for the approach
>>authorizes me to descend to 2700 at the TAA boundary.
>
>
>
> I'm with Mitty on this one. AIM Section 5-4-5.d.4(b) Says:
>
> "Pilots entering the TAA and cleared by air traffic control, are
> expected to proceed directly to the IAF associated with that area of
> the TAA at the altitude depicted, unless otherwise cleared by air
> traffic control."
>
> If the clearance was indeed "...maintain 4000 until established" that
> would fit the "..unless otherwise cleared by air traffic control"
> clause.
>
> To put this to a test, ask yourself when would you report established
> on the approach if asked by ATC to ".. report established on the
> approach"? My answer would be when I'm on one of the depicted
> portions of the approach and not the TAA.
>
> I guess one could argue that the TAA is a depicted portion of the
> approach but I can't find any official publication pointing to that
> fact.
>
>
The TAAs have published altitudes; i.e., with underscores as opposed to
MSA altitudes, which are not operational.

"bsalai" <bsalai@rochester.> wrote in message
news:470cab01$0$26364$4c368faf@roadrunner.com...
>
> I'm the least expert of anyone in this discussion, but doesn't the box
> around the 2700 mean that you should maintain 2700, that they expect you
> at that altitude once inside the TAA
>

I believe you're thinking of a Mandatory Altitude, which is indicated by
both underlining and overlining the altitude figure.

bsalai wrote:
>
> I'm the least expert of anyone in this discussion, but doesn't the box
> around the 2700 mean that you should maintain 2700, that they expect you
> at that altitude once inside the TAA

Those are MSA's.

Bee wrote:

> Great cite. Too bad most of the folks here cannot figure out how to
> find this stuff.

Great cite of a pretty good site.

True enough, but if everyone just looked everything up and found the
answers and interpreted everything correctly, we wouldn't have much to
talk about here.

Anyway, I certainly wouldn't fault the OP for raising the question here.
It provoked an interesting discussion and I learned from it.

Dave

"Dave Butler" <asdf@asdf.net> wrote in message
news:1192108987.284178@sj-nntpcache-2.cisco.com...
> Bee wrote:
>
>> Great cite. Too bad most of the folks here cannot figure out how to find
>> this stuff.
>
> Great cite of a pretty good site.
>
> True enough, but if everyone just looked everything up and found the
> answers and interpreted everything correctly, we wouldn't have much to
> talk about here.
>
> Anyway, I certainly wouldn't fault the OP for raising the question here.
> It provoked an interesting discussion and I learned from it.
>
> Dave

Me too.

Al G

Ron Rosenfeld wrote:
> On Wed, 10 Oct 2007 18:26:42 -0700, Bee <Bee@Bmail.com> wrote:
>
>
>>Great cite. Too bad most of the folks here cannot figure out how to
>>find this stuff.
>
>
> At least the question is asked and, in the various answers, these sorts of
> things become known.
> Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

It didn't help that NACO chose to use the MSA box for the TAA area
minimum altitudes rather than the underscore as they have always used
for all other minimum alitudes and as illustrated in the AIM.

They also claim that the TAA area minimum altitudes replace MSAs for
these IAPs. That is incorrect. They make MSAs unnecessay but they do
not replace them. MSAs are not IFR altitudes in this country.