non-vectored NDB IAF

"Bob Gardner" wrote in message
...
Let me join the fray. There is no need whatsoever to intercept the 207
bearing from the NDB and track it outbound, so how about (either heading
090
or 90 degrees to the FAC) turning to 207 plus/minus a wind guess at
station
passage, timing a couple of minutes or more, depending on the
wind...making
an extended holding pattern, IOW, and turning back to an intercept heading
somewhere between 340 and 000? Makes sense to me. Only those pilots who
are
wedded to the 45-180 course reversal would do that much maneuvering.

Is an "extended holding pattern" a permitted course reversal for any
approach, or does the hold have to be charted (as it is at PQF, presumably
for the missed approach)?

Julin Scarfe

On Thu, 09 Sep 2004 06:24:25 GMT, "Julian Scarfe"
wrote:

Is an "extended holding pattern" a permitted course reversal for any
approach, or does the hold have to be charted (as it is at PQF, presumably
for the missed approach)?

In the US, on NACO charts, unless the hold is depicted by a procedure
track, the pilot can fly it any which way (AIM5-4-9 a 1).

On Jepp charts the principal is the same, although the conventions are a
bit different.

On the approach in question, the PT is depicted by a 'barb'. The type of
turn would be considered a 'racetrack'.

==================
AIM 5-4-9
a ...
1. On U.S. Government charts, a barbed arrow indicates the
direction or side of the outbound course on which the procedure turn is
made. Headings are provided for course reversal using the 45 degree type
procedure turn. However, the point at which the turn may be commenced and
the type and rate of turn is left to the discretion of the pilot. Some of
the options are the 45 degree procedure turn, the racetrack pattern, the
tear-drop procedure turn, or the 80 degree « 260 degree course reversal.
Some procedure turns are specified by procedural track. These turns must be
flown exactly as depicted.
====================
--ron

On Thu, 09 Sep 2004 06:24:25 GMT, "Julian Scarfe"
wrote:

Is an "extended holding pattern" a permitted course reversal for any
approach, or does the hold have to be charted (as it is at PQF,
presumably
for the missed approach)?

"Ron Rosenfeld" wrote in message
...

In the US, on NACO charts, unless the hold is depicted by a procedure
track, the pilot can fly it any which way (AIM5-4-9 a 1).

Thanks Ron.

In the UK (and in general under ICAO PANS-OPS rules), course reversals must
be flown as depicted, and they're usually base turns. In particular, in
PANS-OPS there's an admonition that the airspace protected where procedure
turns and base turns are depicted may not be sufficient for racetracks and
holding patterns, though in the UK it is rare for terrain to be an issue at
IAF altitudes.

Julian Scarfe

On Thu, 09 Sep 2004 12:25:15 GMT, "Julian Scarfe"
wrote:

In the UK (and in general under ICAO PANS-OPS rules), course reversals must
be flown as depicted, and they're usually base turns.

In the US, we usually call those "tear drops". If a tear drop is depicted,
either on the NACO or on the Jepp charts, then it must be flown as
depicted, also.

In particular, in
PANS-OPS there's an admonition that the airspace protected where procedure
turns and base turns are depicted may not be sufficient for racetracks and
holding patterns, though in the UK it is rare for terrain to be an issue at
IAF altitudes.

That's true in the US, also. And the "depicted" turns, whether they be
base turns or other depictions are generally used when limited space is
available. This could be due either to terrain or to traffic.

But the majority of our procedure turns are not depicted in this manner.
The limitation for the non-depicted type course reversals is that they be
carried out on the proper side of the final course, and that they be
accomplished within some defined mileage of the point at which one can
begin the PT -- usually ten miles, but if only Category A a/c are using the
field, it could be five miles. And if larger a/c have to be accomodated,
it could be fifteen miles.


--ron

Only those pilots who are wedded to the 45-180 course reversal would
do that much maneuvering.

Or those who are wedded to positive course guidance on the outbound,
as opposed to ded reckoning. ;-)

Greg Esres wrote in message . ..
Only those pilots who are wedded to the 45-180 course reversal would
do that much maneuvering.

Or those who are wedded to positive course guidance on the outbound,
as opposed to ded reckoning. ;-)

You can't be serious

I think you're just being cheeky but in any case here's a detailed
breakdown of the two procedures.

This is no more ded reckoning than you do on *every* published holding
pattern.

Your only needs navigationally are to (i) keep the course to your
right and (ii) to not get too far away from it. If the needle stays on
the right side of your tail and doesn't start moving forward (as in
towards the nose; ideally it will fall back a little as you head
outbound) both of these are totally assured.

Except for pedantry's sake I do not see any benefit to being dead-on
the 207 magnetic bearing on the outbound segment. If it were unsafe
the procedure would not be allowed.

Further, let's look at the turns each procedure requires:

"Hold-style" PT:
1. upon station passage turn right to outbound heading, 90-207 =
117deg
2. after a minute or so outbound as needed, turn right to intercept
the bearing, 207-342 =~ 140deg
3. turn to 027 upon bearing intercept, 342-027 = 45deg

3 turns totaling 300 degrees, all in the same direction too. Pretty
simple and hard to screw up.

"Pedantic" PT:
1. upon station passage turn right to intercept the 207 magnetic
bearing from the beacon. Don't be too fast though or you'll fly right
through it. 90-240 = 150deg
2. Upon bearing intercept turn left 30 deg to establish
3. after appropriate amount of time turn left 45 for the procedure
turn
4. thence right 180 degrees to re-intercept the inbound 027 bearing to
the beacon
5. upon intercept right 45 degrees to establish yourself on the 027
bearing to the beacon

Total 5 turns, two changes of direction, total 450 degrees. Plus,
depending on how much you goof around intercepting the outbound
bearing in steps 1 and 2, you have a great opportunity to leave the
beacon and its protected airspace well behind you.

Now add a 090@20 wind to this and tell me which one of these offers a
better guarantee of not screwing the pooch completely.

Cheers,
-cwk.

Turn outbound for the procedure turn in what seems to be the shortest
turn. There is a whole lot of protected airspace for the procedure
turn. Sometimes there will be a note to not descend to the procedure
turn altitude until established outbound. If there is no such note you
can begin descent to the procedure turn altitude as you begin the turn
outbound.

Nicholas Kliewer wrote:
I was practicing the following NDB-A approach
at F46 (Rockwall -- East of Dallas, TX)

http://204.108.4.16/d-tpp/0409/06323NA.PDF

And asked for the full approach.

Without GPS or vectors what's the best way to get
turned around outbound if I am on a heading of 090
to intercept the NDB IAF? How about if I am
approaching the IAF at a 90 degree intercept angle?

Thanks all,
-Nick

(C Kingsbury) wrote
This is no more ded reckoning than you do on *every* published holding
pattern.

True enough, but most of the time your only purpose in the hold is to
stay in one place for a while. Here, you're about to shoot an NDB
approach. The outbound segment, if flown with positive course
guidance, gives you a chance to establish the crosswind component.
Fly it by DR, and you miss the chance.

Except for pedantry's sake I do not see any benefit to being dead-on
the 207 magnetic bearing on the outbound segment.

Well, if you're confident enough of your skills to not want the extra
chance to establish the crosswind component, and confident enough that
wou will roll out established inbound - go for it.

If it were unsafe
the procedure would not be allowed.

You truly need to disabuse yourself of that notion before it kills
you. Check out the VOR-B for LVJ sometime - a perfect example of how
you can fly an approach with equipment well within allowable
tolerances, to well within PTS standards, and still die.

Michael

This is no more ded reckoning than you do on *every* published
holding pattern.

Bob suggested flying outbound for two minutes or more, so there is
over twice as much ded reckoning as on a standard hold.

A late turn, with a wicked crosswind component could push you
uncomfortably close to the edge of the protected area.

The standard PT keeps you right in the middle of the protected area
most of the time.

Greg Esres wrote in message . ..
This is no more ded reckoning than you do on *every* published
holding pattern.

Bob suggested flying outbound for two minutes or more, so there is
over twice as much ded reckoning as on a standard hold.

Actually my point is that neither this form of PT or an NDB hold are
in fact "ded reckoning." You have positive indication of ground track
based on needle position, direction of movement, and rate of movement.

A late turn, with a wicked crosswind component could push you
uncomfortably close to the edge of the protected area.

The needle will tell you what's going on during the outbound leg.
Plus, you still run this risk with the procedure you've described,
when you go out and do the 45-180 PT.

I will grant that there is a slight advantage to your procedure in
this one area, but I still think it's outweighed by the significantly
increased opportunities it offers to screw up in other ways.

The standard PT keeps you right in the middle of the protected area
most of the time.

Try flying this with a handheld GPS ground track turned on, fly it
twice each way. I'll bet you five bucks the difference is minimal.

Best,
-cwk.