Question of aborted landing after instrument approach

I quickly studied a few ILS charts for airports for which I know there
are tall antennas nearby. I can't find any examples where a turn before
MAP can cause a problem. The turn always seem to be away from the
antennas, and when there are antennas in the direction of the turn, the
procedure calls for a straight-ahead climb before turning to avoid
those antennas. I am not disputing the TERPS criteria, but the best way
to illustrate these lurking dangers is through real examples instead of
hypothetical ones.





Bob Noel wrote:
In article ,
Newps wrote:

From a well known instrument instructor and writer:


I don't believe this is true. Follow the instructions WHEREVER you
start the miss, and there is no need to fly to the MAP, UNLESS specified.

Standard challenge of mine for many decades: Find me an approach
anywhere where executing the miss as stated will get you in trouble
if you miss "early" inside the FAF.

Well, I don't know of any that actually would have a problem, however, I do
know for a fact that (at least in the 2001 timeframe) the TERPS does NOT
provide for any terrain protection if a missed approach procedure is started
early.

So that well known instrument instructor and writer might want to read up
on the TERPS.

--
Bob Noel
Looking for a sig the
lawyers will hate

In article . com,
"Andrew Sarangan" wrote:

I quickly studied a few ILS charts for airports for which I know there
are tall antennas nearby. I can't find any examples where a turn before
MAP can cause a problem. The turn always seem to be away from the
antennas, and when there are antennas in the direction of the turn, the
procedure calls for a straight-ahead climb before turning to avoid
those antennas. I am not disputing the TERPS criteria, but the best way
to illustrate these lurking dangers is through real examples instead of
hypothetical ones.

Just because a danger doesn't exist right now does not mean it can't
occur in the future.

--
Bob Noel
Looking for a sig the
lawyers will hate

Andrew Sarangan wrote:
Why is ODP an emergency procedure?

Because it is not in accordance with your air traffic clearance. See
AIM 5-5-5.

Jose wrote:

Why is ODP an emergency procedure?


It isn't. However, a go-around started in IMC far enough past the MAP
at an airport where the missed approach procedure does not provide
obstacle clearance if it's started past the MAP could certainly qualify
as an emergency for purposes of choosing a course of action.

Read AIM 5.5.5

The ODP would be a reasonable course of action in that circumstance, at
least until a point at which the missed approach could be joined.

Jose

That would be your argument if any enforcement action resulted in the
event of a loss of separation.

Bob Noel wrote:

In article , Sam Spade wrote:


His respone is 100% correct.


not quite.

Just as starting a missed approach procedure too early, flying
the missed too late can put you into unprotected airspace.


No doubt about it. Nonetheless, his answer is still correct. The moral
of the story is that you better know what you are doing and have
adequate climb performance to overcome the balked landing problem when
you depart MDA on a high HAT/HAA instrument approach procedure.

One of the best assurances against getting into this bind is to have
landing assured when leaving MDA; i.e., a clear view of the runway.

Newps wrote:



Jim Macklin wrote:

On a missed approach begun early, prior to reaching the MAP, climb to
the missed approach altitude but do not turn until reaching the MAP or
that point indicated on the chart. If a turn is indicated, perform
that turn as charted, but not prior to the expected position past the
MAP.




From a well known instrument instructor and writer:


I don't believe this is true. Follow the instructions WHEREVER you
start the miss, and there is no need to fly to the MAP, UNLESS specified.

Standard challenge of mine for many decades: Find me an approach
anywhere where executing the miss as stated will get you in trouble
if you miss "early" inside the FAF.

I've no objection if you DO it to feel good, but I don't believe it
is a REQUIREMENT, built into the system.


Best...
John

John obviously doesn't know TERPs criteria.

Jim Macklin wrote:

The instrument approach provides terrain clearance along and
to a limited area either side of the final and missed
approach path charted. A climb along the approach path is
safe, but if you begin a turn prior to the charted location,
you run the risk of hitting an obstruction.
Consider a fictional IAP with a missed approach that calls
for a right turn and going direct to a fix. If it is an
ILS, the miss will start at 200 feet or lower from over the
runway. But if you miss on the three mile final and start
the turn (and climb) early, you would be about 700 at the
start, but could also be abeam a TV tower.

Perhaps most missed approaches can be flown differently, but
flown to the design, on the track that was flight tested, it
will work on any approach.

The only time an early turn will assure obstacle clearance is where the
missed approach track returns to the final approach fix or facility,
such as the LOM or where a VOR station is the FAF.

Bob Noel wrote:

In article ,
Newps wrote:


From a well known instrument instructor and writer:


I don't believe this is true. Follow the instructions WHEREVER you
start the miss, and there is no need to fly to the MAP, UNLESS specified.

Standard challenge of mine for many decades: Find me an approach
anywhere where executing the miss as stated will get you in trouble
if you miss "early" inside the FAF.


Well, I don't know of any that actually would have a problem, however, I do
know for a fact that (at least in the 2001 timeframe) the TERPS does NOT
provide for any terrain protection if a missed approach procedure is started
early.

So that well known instrument instructor and writer might want to read up
on the TERPS.


TERPs is the same today as it was in 2001 or, for that mater, 1971, when
it comes to turning missed approach criteria. The well known writer
doesn't know what he is talking about.

AIM 5-4-21 b:

"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."

jbskies wrote:

Dave S wrote:

wrote:
On the garden variety Cat 1 ILS you are at 200 feet AGL and over the
approach lights when you reach DH (decision height). How would it be
"too late" to fly the missed approach? If you are genuinely concerned,
pitch for VX instead of VY for any percieved obstacle clearance, but VY
should suffice nicely.



For many Cat1 aircrafts (especially B747/B744), a miss executed by the
auto-land system is commonly for the aircraft to actually tough down
the runway before it spoof up and flying the miss.

You have that wrong. That is the situation for CAT III autoland. With
CAT III approaches the missed approach protection begins at the runway
surface.

To add top the answer, a procedure must be designed and
flown so that the same procedure will be safe anywhere.
Having to remember that an early turn is OK at airport
a,b,c... ..., but not at airport u, and v, and OK again at
x,y,z will be dangerous.



"Bob Noel" wrote in
message
...
| In article
. com,
| "Andrew Sarangan" wrote:
|
| I quickly studied a few ILS charts for airports for
which I know there
| are tall antennas nearby. I can't find any examples
where a turn before
| MAP can cause a problem. The turn always seem to be
away from the
| antennas, and when there are antennas in the direction
of the turn, the
| procedure calls for a straight-ahead climb before
turning to avoid
| those antennas. I am not disputing the TERPS criteria,
but the best way
| to illustrate these lurking dangers is through real
examples instead of
| hypothetical ones.
|
| Just because a danger doesn't exist right now does not
mean it can't
| occur in the future.
|
| --
| Bob Noel
| Looking for a sig the
| lawyers will hate
|