GPS approaches with Center

At least "there is a Victor airway running through the TAA
somewhere" and "the IAF is anchored on a Victor airway" are statements
with different meaning to me.

I agree with your criticisms of the method of attachment and the lack
of information available to the pilot.

I believe the statement you quoted above was sorta "high level." Even
non-GPS approaches often are connected to the enroute segment via
feeder routes, rather than having an IAF on the airway.

"Steven P. McNicoll" wrote:

wrote in message
...

A few centers accept them without much heartburn. Most centers, though,
fight them. Where they are needed the most; i.e., out in the
intermountain west with no radar coverage at TAA altitudes, ATC claims
that FAA controllers don't have the training to provide non-radar
separation in TAA areas.


Can you cite that claim?

Why don't you contact Brad W. Rush, Deputy Manager of AVN-100. He can tell
you all you want to know about centers and TAAs.

Considered by AFS-420 and AVN-100, not to mention common sense.

"Steven P. McNicoll" wrote:

"Greg Esres" wrote in message
...

Any airway that passes through one of the TAA sectors is considered
connected, but it's difficult to tell when looking at an approach
plate.


Considered by whom? A Victor airway passing through a TAA is not the same
as "IAFs anchored
on Victor airways unless there are no IAFS (I.e., radar required)."


Still, even considering that, what you say may be true.


One need only examine the TPPs to see that it's true.

"Steven P. McNicoll" wrote:

"Greg Esres" wrote in message
...

Flight Procedures.


Citation?

FAA Order 8260.45A, "Terminal Arrival Area (TAA) Design Criteria, specifically,
the following paragraph:

8.5 CONNECTION TO EN ROUTE STRUCTURE.
Normally, a portion of the TAA will overlie an airway. If this is not the case,

construct at least one feeder route from an airway fix or NAVAID to the TAA
boundary aligned along a direct course from the en route fix/NAVAID to the
appropriate IF(IAF) and/or T IAF(s) (see figure 5F). Multiple feeder routes may
be established if the procedure specialist deems necessary.

I thought you had all these orders in hand, Steve.

Snowbird wrote:

Greg Esres wrote in message . ..
chart the GPS approaches completely independently of the
ground-based navaid and airway system on which ATC currently still
relies.

I bet if you check, you'll see that an airway runs through one of the
TAA sectors. That's the case with our local TAAs.

I'll check. In at least one case, I know you're right (though
it only runs through two of the three TAAs) but ....

....whether or not this is true, it
A. doesn't help the pilot understand how the approach fits into
the ground based navaid/Victor airway system because the airways
aren't charted on the IAP and the TAAs/IAFs aren't charted on the
low altitude enroute
B. doesn't help the controller understand the position of the
various RNAV approach fixes if they aren't in their host
computer database
C. it differs substantively IMO from the original statement, which
was IIRC that all GPS approaches developed in the last three years
have their IAFs anchored on Victor airways unless they are radar-
required and have no IAFs.

That statement excluded TAA approaches, and was subsequently corrected to either feeder fixes or IAFs.

Considered by AFS-420 and AVN-100, not to mention common sense.

I agree that it's common sense.

One thing about TAA's that bothers me is the definition of the
sectors. The distance is to the IAF in the right or left base, but
the bearings are to the IF. GPSs don't display the bearing to the IF,
when you're headed to one of the "T" IAFs. (But you can get it on the
KLN-94 by scrolling through the fixes in the active flight plan.)

Greg Esres wrote:

Considered by AFS-420 and AVN-100, not to mention common sense.

I agree that it's common sense.

One thing about TAA's that bothers me is the definition of the
sectors. The distance is to the IAF in the right or left base, but
the bearings are to the IF. GPSs don't display the bearing to the IF,
when you're headed to one of the "T" IAFs. (But you can get it on the
KLN-94 by scrolling through the fixes in the active flight plan.)

I'm not sure I follow you. If I am going to a right or left base IAF,
that is my active waypoint, with bearing and distance appropriate to the
TAA area. If I am in the straight-in area, then the IF is my active
waypoint.

Am I missing something?

Having said that, If TAAs ever really fly (no pun intended) the TAAs
would likely be part of a moving map at some point. Then, it would be
pretty straight forward.

that is my active waypoint, with bearing and distance appropriate to
the TAA area.

The way the TAA's are charted, the bearings that define the sectors
are not to the active waypoint (except for the straight-in), they're
defined to the IF. (This is a bit clearer on the NACO charts.)

And the AIM says
----------snip-------------
TAA area lateral boundaries are identified by magnetic course to the
IF(IAF).
----------snip-------------

Greg Esres wrote:

that is my active waypoint, with bearing and distance appropriate to
the TAA area.

The way the TAA's are charted, the bearings that define the sectors
are not to the active waypoint (except for the straight-in), they're
defined to the IF. (This is a bit clearer on the NACO charts.)

And the AIM says
----------snip-------------
TAA area lateral boundaries are identified by magnetic course to the
IF(IAF).
----------snip-------------

I had missed that. I've only flown a couple of these and it was in the
straight-in area both times. Without a moving map display of the areas
that could be a trap using either base leg area.

wrote in message ...

That statement excluded TAA approaches, and was subsequently corrected to either feeder fixes or IAFs.

Um, no, not in the original post to which I was responding. It
didn't exclude anything, nor did the subsequent correction state
that a Victor airway running *through* the TAA was considered
a feeder route or being "anchored" or whatever you consider it as.

I *think* it's still not true, but as qualified, it does apply
to several approaches I had in mind -- they do have TAAs and
at least one V airway running through a TAA. Or, they have
a feeder fix from an intersection, even if it might be an
intersection no sane pilot or ATCs would use as a feeder (while
others which would make sense are not charted). Hopefully I'll
have a little time to do some checking this weekend.

Cheers,
Sydney