VOR approach- when to descend from the FAF

"Mark Hansen" wrote in message
...

I spend that minute or so making sure my heading and approach airspeed
are
under control, and then simply catch up to the descent afterward when the
needle comes back. It'll be interesting to see how other people do it,
but
that's the way I was trained.

I was taught to begin the descent at station passage (using the 5 'T's).
It's never taken more than just a very few seconds for the CDI to start
coming back in. A minute seems awfully long.

Yeah, I was just throwing that out as a ballpark figure. It shouldn't take
very long at all, which means it's even less of a problem to catch up to the
descent afterward.

I prefer to have the altitude under me rather than above me throughout the
approach, but, at that point it's not like you're going to fly into anything
if you're 50 feet lower immediately after crossing the station than if you
waited. Or, you have bigger issues.

If I were taking the IFR checkride, though, I'd definately hold the altitude
until I could demonstrate to the examiner that I had recaptured the CDI was
100% established. That's the kind of thing my examiner would have expected
and how I was taught to do it. (caveat: Since they almost always use the
examiner, they teach to his specific expectations, which may be a factor.)

-c
CP-ASEL-IA

On Thu, 21 Feb 2008 09:27:00 -0800, "gatt"
wrote:


"Terence Wilson" wrote in message
.. .
When flying a VOR approach in which the FAF is defined by the VOR, is
it appropriate to start the descent to the MAP, or next stepdown,
immediately after overflying the VOR or should I wait until I have
positive course guidance for the final approach segment?

I ask because it can sometimes take 1-2nm for the CDI to move, which
may require a rushed descent to the MAP on some approaches.

I spend that minute or so making sure my heading and approach airspeed are
under control, and then simply catch up to the descent afterward when the
needle comes back. It'll be interesting to see how other people do it, but
that's the way I was trained.

-c


Trained well, in my opinion.

That's exactly the way to do it, IMHO.

For you folks voting to go missed if the CDI remains fully deflected
when passing the FAF...

I hope you mean that you will proceed to the missed approach fix and
then go missed. Initiating a missed approach early is not advised
because
obstacle clearance is not guarenteed per the AIM:

"...Reasonable buffers are provided for normal maneuvers. However, no
consideration is given to an abnormally early turn. Therefore, when an
early missed approach is executed, pilots should, unless otherwise
cleared by ATC, fly the IAP as specified on the approach plate to the
missed approach point at or above the MDA or DH before executing a
turning maneuver."
(5.4.21b)


wrote:
On Feb 19, 2:53�pm, Les Izmore wrote:

This is being treated like some kind of academic
angels-on-the-head-of-a-pin question. �It is not.

It is academic.

Two choices, very simple. Either you are on the final approach
course, or not. If not, you go missed, nothing complicated.

They usually "try harder" �to reintercept the course while going still
lower. �This practially always ends up in a situation that could be
disastrous in actual conditions.

Then that pilot is behind the plane. See above for choices of
action. Really very academic. It may not be a training issue, but a
currency issue, thus the IMPORTANCE of staying current.

and I base that opinion on watching a lot of
pilots, many of them experienced and �instrument rated, screw
approaches up pretty badly, for any number of reasons.

At anytime a pilot "screws up" as you alleged, missed is always that
option. Very academic. I personally experience quite the opposite
for IA pilots when I was their safety pilot, they get it right and
never gone full deflection. I am not a CFI by any means for what this
is worth.

I don't care what the "book" says.

Book is very clear. If you are not on the final approach course
within the established tolerances, you go missed. What part of the
book is hard to understand?

The orignal question is a very elementary question for IA flying.

For what it's worth, in my 600 hours of instrument flying, it takes a
hell of a lot more then 1 or 2 miles for the CDI to start moving. If
that is happening to the original poster, or you experienced that,
then there is something wrong with that station signal or airplane
equipment and a missed approach is in order. KMBO has the VOR alpha
approach and I can pick up the VOR signal strong on both my NAV1 and
NAV2 within 20 miles.

When you are within 1 or 2 miles of a final approach fix (I.E. VOR) it
is normal to get a full deflection from that "zone of confusion" for
the CDI. The needles will recapture within a mile or two of station
passage.

But you do not descend before getting the from flag on your NAV1 or
NAV2 AND being on the final approach course. If you don't get a from
flag you go missed even if you are on the final approach course as
something is radically wrong equipment wise.. Note the word AND, both
being on the approach course AND from flag, BOTH must be present.
VERY SIMPLE!

The original question was so basic, that it sounded like an Mx
question..

Allen

I don't think anyone advocated going missed " if the CDI remains
fully deflected when passing the FAF..."

The debate was whether it was prudent to begin a descent while the
needle was fully deflected.




On Mon, 25 Feb 2008 11:54:58 -0800 (PST), wrote:

For you folks voting to go missed if the CDI remains fully deflected
when passing the FAF...

I hope you mean that you will proceed to the missed approach fix and
then go missed. Initiating a missed approach early is not advised
because
obstacle clearance is not guarenteed per the AIM:

"...Reasonable buffers are provided for normal maneuvers. However, no
consideration is given to an abnormally early turn. Therefore, when an
early missed approach is executed, pilots should, unless otherwise
cleared by ATC, fly the IAP as specified on the approach plate to the
missed approach point at or above the MDA or DH before executing a
turning maneuver."
(5.4.21b)


wrote:
On Feb 19, 2:53?pm, Les Izmore wrote:

This is being treated like some kind of academic
angels-on-the-head-of-a-pin question. ?It is not.

It is academic.

Two choices, very simple. Either you are on the final approach
course, or not. If not, you go missed, nothing complicated.

They usually "try harder" ?to reintercept the course while going still
lower. ?This practially always ends up in a situation that could be
disastrous in actual conditions.

Then that pilot is behind the plane. See above for choices of
action. Really very academic. It may not be a training issue, but a
currency issue, thus the IMPORTANCE of staying current.

and I base that opinion on watching a lot of
pilots, many of them experienced and ?instrument rated, screw
approaches up pretty badly, for any number of reasons.

At anytime a pilot "screws up" as you alleged, missed is always that
option. Very academic. I personally experience quite the opposite
for IA pilots when I was their safety pilot, they get it right and
never gone full deflection. I am not a CFI by any means for what this
is worth.

I don't care what the "book" says.

Book is very clear. If you are not on the final approach course
within the established tolerances, you go missed. What part of the
book is hard to understand?

The orignal question is a very elementary question for IA flying.

For what it's worth, in my 600 hours of instrument flying, it takes a
hell of a lot more then 1 or 2 miles for the CDI to start moving. If
that is happening to the original poster, or you experienced that,
then there is something wrong with that station signal or airplane
equipment and a missed approach is in order. KMBO has the VOR alpha
approach and I can pick up the VOR signal strong on both my NAV1 and
NAV2 within 20 miles.

When you are within 1 or 2 miles of a final approach fix (I.E. VOR) it
is normal to get a full deflection from that "zone of confusion" for
the CDI. The needles will recapture within a mile or two of station
passage.

But you do not descend before getting the from flag on your NAV1 or
NAV2 AND being on the final approach course. If you don't get a from
flag you go missed even if you are on the final approach course as
something is radically wrong equipment wise.. Note the word AND, both
being on the approach course AND from flag, BOTH must be present.
VERY SIMPLE!

The original question was so basic, that it sounded like an Mx
question..

Allen