Crossing a stepdown fix high

David Megginson wrote:

Greg Esres writes:

To comment that "if they fly the approach as published, they won't hit
anything" is a very shallow analysis. Not every CFIT deviated
intentionally from the published approach.

The other question is what "as published" means for an NPA -- do you
make a vertical descent at every stepdown fix? The whole point of an
NPA is that there is no vertical profile published, only a series of
minimum altitudes.

Very well stated.

I was not advocating "dive and drive", whatever that means. The point I was
trying to make was that why stay above the published heights intentionally.
My comment about "get down as fast as possible" is perhaps overzealous and
was not meant to advocate go down really fast, but rather I meant get down
to the published altitude, and not stay above it purposely.

The protection is the same. If pilots can't stop a descent whether going
1000' per minute of 300' per minute is the real issue. Something else is
wrong if the "safer" rate of descent is going to save you. Correcting the
real problem is the solution, not making up rules for hiding the problem or
adding a safety net.

Busting the stepdown fixes is the problem - not the descent rate.

I will concede that the net effect of slower descent rates would be less
accidents, however I am more concerned that pilots use that as a crutch
rather than ensuring they execute approaches appropriately (not descending
below minimums).


wrote in message
...


Tim J wrote:

So what are you saying? The approach chart is/was wrong or the pilots
made
an error?

The pilots made an error under lots of pressure and adverse weather
conditions.
The list of fatal accident reports where stepdown fixes are busted in G/A
during
IMC is a very long list indeed.

The protection offerred by dive-and-drive is substantially less than with
a
constant angle or even a constant rate descent.

I guess this word hasn't gotten very far in the light aircraft world.

Again, I am not advocating "dive and drive" - my point was that staying
above the published altitudes was questionable.

wrote in message
...


Tim J wrote:

I was just trying to point out the obstacle clearances that the approach
charts provide.

I would like to see an accident report that found that the approach
chart
was incorrect and caused a crash. Does anyone have an example?

I think rather it is the (improper) execution of the approach that is
the
cause of the supposed huge set of examples of crashes. If you all find
it
easier to make up your own descent profiles, go right ahead. I will not
try
to convince you otherwise. I will continue to fly them as published.

What makes you think "as published" means dive and drive any more than it
means
constant angle or constant rate?

It really does not matter if the CFIT deviated intentionally or not. Most
likely if CFIT implies that they descended below the minimum published
altitudes for that segment.

Perhaps I am wrong (as so many of you are pointing out)
but if I make a descent rate to arrive at a step down higher than published,
it seems as though my descent rate has a good chance to not get me to the
MDA when the time is up (or distance) and I have to go missed. So
eventually I would have to do the dreaded "dive and drive" later anyway.

wrote in message
...


David Megginson wrote:

Greg Esres writes:

To comment that "if they fly the approach as published, they won't hit
anything" is a very shallow analysis. Not every CFIT deviated
intentionally from the published approach.

The other question is what "as published" means for an NPA -- do you
make a vertical descent at every stepdown fix? The whole point of an
NPA is that there is no vertical profile published, only a series of
minimum altitudes.

Very well stated.

Do restrict your altitude to the MEAs enroute too? The stepdowns depict the
minimum altitudes for each segment of the approach. There is nothing regulatory
about flying at those minimums. What you are advocating is what others have
called 'dive and drive', ie decending quickly at each crossing then leveling at
the mda for that segment until hitting the next stepdown fix. This certainly
does increase the workload (you have less time to react to the altitude if it is
decreasing at 1000 fpm instead of 3-500 fpm), as well as the consequences for
being a little bit behind the airplane. It also gives you fewer options
(altitude) should the engine start coughing. Just from the ergonomics
standpoint, it is more stressful to you and your passengers, not to mention to
the engine (shock cooling) and airframe. Most of the time, you've got plenty of
room between the fixes to do a gentle descent and still get you at the final MDA
in plenty of time to find the airport.




--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930 Fax 401/884-7950
email
http://www.andraka.com

"They that give up essential liberty to obtain a little
temporary safety deserve neither liberty nor safety."
-Benjamin Franklin, 1759

It's probably about time for someone to bring up the Aspen approach =
again.
Be a little high and/or fast there, and you won't get down in time to =
land.
---JRC---

"Ray Andraka" wrote in message =
...
Do restrict your altitude to the MEAs enroute too? The stepdowns =
depict the
minimum altitudes for each segment of the approach. There is nothing =
regulatory
about flying at those minimums. What you are advocating is what =
others have
called 'dive and drive', ie decending quickly at each crossing then =
leveling at
the mda for that segment until hitting the next stepdown fix. This =
certainly
does increase the workload (you have less time to react to the =
altitude if it is
decreasing at 1000 fpm instead of 3-500 fpm), as well as the =
consequences for
being a little bit behind the airplane. It also gives you fewer =
options
(altitude) should the engine start coughing. Just from the ergonomics
standpoint, it is more stressful to you and your passengers, not to =
mention to
the engine (shock cooling) and airframe. Most of the time, you've got =
plenty of
room between the fixes to do a gentle descent and still get you at the =
final MDA
in plenty of time to find the airport.
--
--Ray Andraka, P.E.

"Tim J" wrote in
. net:

Again, I am not advocating "dive and drive" - my point was
that staying above the published altitudes was
questionable.

I'm beginning to think your judgment is questionable. The
stepdown fixes give only minimum altitudes, no maximum. That
means you can't go below, but can safely and legally be above,
the altitude. There is no requirement at all to be at a
stepdown altitude immediately, unless there is a line *above*
the altitude.

--
Regards,

Stan

"John R. Copeland" wrote in
:

It's probably about time for someone to bring up the Aspen
approach again. Be a little high and/or fast there, and you
won't get down in time to land. ---JRC---

I haven't flown that approach, but I've studied the approach
plate. The stepdown fixes aren't that much - you don't have to
hurry, because there isn't that much altitude change. The big
change is the final descent, after the stepdown fixes, and if
you get too low or a little off course, you'll land much more
quickly than you intended.

--
Regards,

Stan

"Stan Gosnell" me@work wrote in message =
...
"John R. Copeland" wrote in
:=20
=20
It's probably about time for someone to bring up the Aspen
approach again. Be a little high and/or fast there, and you
won't get down in time to land. ---JRC---
=20
I haven't flown that approach, but I've studied the approach=20
plate. The stepdown fixes aren't that much - you don't have to=20
hurry, because there isn't that much altitude change. The big=20
change is the final descent, after the stepdown fixes, and if=20
you get too low or a little off course, you'll land much more=20
quickly than you intended.
=20
--=20
Regards,
=20
Stan

Roger that, too, Stan! My wife dislikes that valley.
BTW, Aspen approach is pretty understanding if you tell them
you need to make a 360 to lose some altitude after you get the field in =
sight.
(Of course, we're talking fixed-wing performance here.)
---JRC---

"Tim J" wrote in message
. net...
I was not advocating "dive and drive", whatever that means. The point I
was
trying to make was that why stay above the published heights
intentionally.
My comment about "get down as fast as possible" is perhaps overzealous and
was not meant to advocate go down really fast, but rather I meant get down
to the published altitude, and not stay above it purposely.

The protection is the same. If pilots can't stop a descent whether going
1000' per minute of 300' per minute is the real issue. Something else is
wrong if the "safer" rate of descent is going to save you. Correcting the
real problem is the solution, not making up rules for hiding the problem
or
adding a safety net.

Busting the stepdown fixes is the problem - not the descent rate.

I will concede that the net effect of slower descent rates would be less
accidents, however I am more concerned that pilots use that as a crutch
rather than ensuring they execute approaches appropriately (not descending
below minimums).


Whoa! I had to get in here on this one... A crutch? Using something that
will result in less accidents is a crutch? I think NOT! A stabilized
approach will always be safer than step-downs.

Just my 2cents. I'll sit back down now.

Harvey