RNAV vectors

Stan Prevost wrote:


Roy, apparently VTF works much differently on the 480 than the 430 and
sounds correctly implemented. On the 430, VTF doesn't work properly on a
dogleg approach. It sets up for the dogleg intermediate segment rather than
the extended final course. Have you checked the 480 for a dogleg, such as

http://www.naco.faa.gov/d-tpp/0612/05924VDB.PDF
or
http://www.naco.faa.gov/d-tpp/0612/06712R23.PDF ?




The VTF on the 480 seems to work the same way. it extends the
dogleg (the R-250 off RQZ).

"Sam Spade" wrote in message
...
Stan Prevost wrote:


On the 430, VTF doesn't work properly on a
dogleg approach. It sets up for the dogleg intermediate segment rather
than the extended final course.


It seems to me to work correctly. Using your example of KEKX RNAV 23, if
I select VTF, as you say, I get a track line of 270 magnetic to JEXUD.
That would be the correct course to intercept for vectors to "final."

The issue is FAA terminology that is predicated on the ILS case.

It works the way that we pilots would usually prefer that it work, but the
problem is that the 7110.65 used in conjunction with the definitions in the
P/CG, doesn't allow for controllers issuing vectors to an approach other
than to the final approach course as defined in the P/CG, and this results
in some controllers doing it one way and others doing it another way, and
pilots never know (except through local experience) what a controller
intends if s/he says Vectors To Final. The manual should be revised to
allow vectors to an intermediate dogleg segment. Maybe an ASRS report will
get the concern into the system.

"Ron Natalie" wrote in message
...
Stan Prevost wrote:


Roy, apparently VTF works much differently on the 480 than the 430 and
sounds correctly implemented. On the 430, VTF doesn't work properly on a
dogleg approach. It sets up for the dogleg intermediate segment rather
than the extended final course. Have you checked the 480 for a dogleg,
such as

http://www.naco.faa.gov/d-tpp/0612/05924VDB.PDF
or
http://www.naco.faa.gov/d-tpp/0612/06712R23.PDF ?




The VTF on the 480 seems to work the same way. it extends the
dogleg (the R-250 off RQZ).

Thanks, Ron. I have been wondering how that worked in the 480.

Stan Prevost wrote:

It works the way that we pilots would usually prefer that it work, but the
problem is that the 7110.65 used in conjunction with the definitions in the
P/CG, doesn't allow for controllers issuing vectors to an approach other
than to the final approach course as defined in the P/CG, and this results
in some controllers doing it one way and others doing it another way, and
pilots never know (except through local experience) what a controller
intends if s/he says Vectors To Final. The manual should be revised to
allow vectors to an intermediate dogleg segment. Maybe an ASRS report will
get the concern into the system.


The only effective way to get it addressed is for a user group (such as
AOPA) to submit it to ATPAC (Air Traffic Control Advisory Committee).

But, according to the FAA ATO chiefs, vectors can be given to final only
where the final approach course is on the video map. And, they claim
that is done only with ILS approaches that are in an area with adequate
radar coverage. So, I presume those chiefs would say it is a non--issue
if submitted to ATPAC.

Sam Spade writes:

That is not the point. Direct-to on a GNS400/500 will not yield the
unpublished extension of the final approach course unless you happen to
be in the correct position when you activate direct-to.

Maybe that's why they call it Direct-To, and not
Reveal-Final-Approach-Course. It's a mode you use when you just want
a line pointing you to a specific spot.

I'm surprised by the amount of time people are willing to spend
twirling knobs and pressing buttons on the GPS, when they could just
look at the display and fly towards the fix that interests them. How
did people survive before GPS?

--
Transpose mxsmanic and gmail to reach me by e-mail.

Mxsmanic wrote:
Sam Spade writes:


I'm surprised by the amount of time people are willing to spend
twirling knobs and pressing buttons on the GPS, when they could just
look at the display and fly towards the fix that interests them.

If you're flying VFR no problem with that. If you're IFR that is not
very well provided for unless ATC is providing an off-route altitude.


How did people survive before GPS?


They didn't do direct very often except for radar vectors.

Sam Spade writes:

If you're flying VFR no problem with that. If you're IFR that is not
very well provided for unless ATC is providing an off-route altitude.

You can zoom a moving map display and carefully fly towards a
displayed fix. I don't see how it would be any less accurate than
flying towards needles or bars on a more traditional instrument. You
don't have to have a complicated system for steering the aircraft. As
long as you can determine where you are and where you are going
without external visibility, you can fly IFR.

Of course, if there are regulatory barriers that require you to use
some automated GPS function, that could be an issue, but it's a
political and administrative one rather than an operational one.

I worry that sometimes pilots may become so wrapped up in twiddling
with their GPS units that they forget where they are going and end up
half buried in a mountainside.

They didn't do direct very often except for radar vectors.

There are times when GPS seems like overkill. The solution should not
be more complex than the problem.

--
Transpose mxsmanic and gmail to reach me by e-mail.

"Sam Spade" wrote in message
...

Stan Prevost wrote:

It works the way that we pilots would usually prefer that it work, but
the problem is that the 7110.65 used in conjunction with the definitions
in the P/CG, doesn't allow for controllers issuing vectors to an approach
other than to the final approach course as defined in the P/CG, and this
results in some controllers doing it one way and others doing it another
way, and pilots never know (except through local experience) what a
controller intends if s/he says Vectors To Final. The manual should be
revised to allow vectors to an intermediate dogleg segment. Maybe an
ASRS report will get the concern into the system.

The only effective way to get it addressed is for a user group (such as
AOPA) to submit it to ATPAC (Air Traffic Control Advisory Committee).

But, according to the FAA ATO chiefs, vectors can be given to final only
where the final approach course is on the video map. And, they claim that
is done only with ILS approaches that are in an area with adequate radar
coverage. So, I presume those chiefs would say it is a non--issue if
submitted to ATPAC.


The full rule (almost) is given in 7110.65R, excerpted below. As to policy
for what goes on the scope, I have no idea. I have been told that it is
decided locally for each facility.

They can hide their heads in the sand and pretend that vectors are given
only to ILS approaches, but it is everyday practice for vectors to be given
to NPAs also.


5-9-1. VECTORS TO FINAL APPROACH COURSE

Except as provided in para 7-4-2, Vectors for Visual Approach, vector
arriving aircraft to intercept the final approach course:

a. At least 2 miles outside the approach gate unless one of the
following exists:

1. When the reported ceiling is at least 500 feet above the MVA/MIA
and the visibility is at least 3 miles (report may be a PIREP if no weather
is reported for the airport), aircraft may be vectored to intercept the
final approach course closer than 2 miles outside the approach gate but no
closer than the approach gate.

2. If specifically requested by the pilot, aircraft may be vectored to
intercept the final approach course inside the approach gate but no closer
than the final approach fix.

EXCEPTION. Conditions 1 and 2 above do not apply to RNAV aircraft
being vectored for a GPS or RNAV approach.

b. For a precision approach, at an altitude not above the
glideslope/glidepath or below the minimum glideslope intercept altitude
specified on the approach procedure chart.

c. For a nonprecision approach, at an altitude which will allow
descent in accordance with the published procedure.

NOTE-
A pilot request for an "evaluation approach," or a "coupled approach,"
or use of a similar term, indicates the pilot desires the application of
subparas a and b.

d. EN ROUTE. The following provisions are required before an aircraft
may be vectored to the final approach course:

1. The approach gate and a line (solid or broken), depicting the final
approach course starting at or passing through the approach gate and
extending away from the airport, be displayed on the radar scope; for a
precision approach, the line length shall extend at least the maximum range
of the localizer; for a nonprecision approach, the line length shall extend
at least 10NM outside the approach gate; and

2. The maximum range selected on the radar display is 150 NM; or

3. An adjacent radar display is set at 125 NM or less, configured for
the approach in use, and is utilized for the vector to the final approach
course.

4. If unable to comply with subparas 1, 2, or 3 above, issue the
clearance in accordance with para 4-8-1, Approach Clearance.

REFERENCE-
FAAO 7110.65, Approach Clearance, Para 4-8-1.
FAAO 7110.65, Final Approach Course Interception, Para 5-9-2.

"Roy Smith" wrote:

Anybody ever get vectors to final for RNAV approaches?

Sure. And what's so cool about the internet today is that not only can I
show you the chart for the approach
(http://204.108.4.16/d-tpp/0612/00286VDG24.PDF),

That's not exaactly what I was talking about. I wouldn't be surprised to get
vectors to that one, since it's a VOR/DME approach with GPS overlay. I'm
talking about RNAV approaches only.

--
Dan
C-172RG at BFM

Mxsmanic wrote:


Of course, if there are regulatory barriers that require you to use
some automated GPS function, that could be an issue, but it's a
political and administrative one rather than an operational one.

As the system moves to RNP, tracking the on-course becomes an absolute
requirement.

Also, the newer breed of autopilots for light aircraft are really good.
Having the autopilot track the course and fly the bird under IFR
unloads the pilot a whole lot so he/she can more effectively manage the
task at hand.


I worry that sometimes pilots may become so wrapped up in twiddling
with their GPS units that they forget where they are going and end up
half buried in a mountainside.


Not if you have a terrain database. ;-)