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* Ron Rosenfeld :
Hm... interesting. "optimum rate consistent with the operating
characteristics of the aircraft". This is fuzzy.

Nothing wrong with giving the pilot discretion over the rate of descent.
However, there is a requirement to notify ATC if climb/descent rates will
be less than 500 fpm.

OK, that makes sense. Never heard of that requirement yet, thanks for
that. Will check our regulations here about comparable requirements.

You seem to be defining "optimum" as equivalent to "economic". I see no
such implication in the US.

Well, what other interpretations of "optimum rate of descend" would
you have in mind? If they didn't have anything specific in mind, they
could have written "any rate consistent with the operating
characteristics". Which would be kinda superfluous as you should never
climb/descend with a rate not being consistent with the operating
characteristics.

My definition of "optimum rate of descend" without further reference to
the parameters for determination of optimality would be something along
the lines of "the minimum rate of descend required to reach a destination
altitude complying to all altitude and speed restrictions as well as
maintaining target speed". This rate is of course a function of time,
with the result being roughly what FMS computes for VNAV as well. :-)

Well, Europe has to handle a lot fewer aircraft than does US ATC. So
maybe hat's why they need more regulations. But wait, you stated that
this is an "unwritten rule". So it's not a regulation, but merely an
expectation.

Yep. But compliance with that is quite universally as far as I'm told by
controllers. :-)

The AIM is available on line. Look at www.faa.gov for the publications.
It is not regulatory, but its procedures are generally followed.

Thanks!


Best regards,
Daniel

On Mon, 28 Nov 2005 06:35:53 +0000 (UTC), Daniel Roesen
wrote:

* Ron Rosenfeld :
Hm... interesting. "optimum rate consistent with the operating
characteristics of the aircraft". This is fuzzy.

Nothing wrong with giving the pilot discretion over the rate of descent.
However, there is a requirement to notify ATC if climb/descent rates will
be less than 500 fpm.

OK, that makes sense. Never heard of that requirement yet, thanks for
that. Will check our regulations here about comparable requirements.

You seem to be defining "optimum" as equivalent to "economic". I see no
such implication in the US.

Well, what other interpretations of "optimum rate of descend" would
you have in mind? If they didn't have anything specific in mind, they
could have written "any rate consistent with the operating
characteristics". Which would be kinda superfluous as you should never
climb/descend with a rate not being consistent with the operating
characteristics.


I typically climb in the neighborhood of a 1000 fpm and descend
between 800 and 1200 fpm.

If I have a descent to and cross at, I'll adjust the rate of descent
to get me down within a mile or two of the crossing point.
However if I'm kept "up there" too long, I'm not going to blow my, or
my passengers ear drums with too fast a descent.

If I'm at cruise, backing off on the throttle 5" will give me 500 fpm
while the speed stays constant. If need be I can slow down a *bit*
which will give me a steeper descent yet.

However I prefer to keep the descent to about 800 and calculate how
far out I need to start down. If I'm within a minute or two of my
limits I'll call ATC and request to start down.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
My definition of "optimum rate of descend" without further reference to
the parameters for determination of optimality would be something along
the lines of "the minimum rate of descend required to reach a destination
altitude complying to all altitude and speed restrictions as well as
maintaining target speed". This rate is of course a function of time,
with the result being roughly what FMS computes for VNAV as well. :-)

Well, Europe has to handle a lot fewer aircraft than does US ATC. So
maybe hat's why they need more regulations. But wait, you stated that
this is an "unwritten rule". So it's not a regulation, but merely an
expectation.

Yep. But compliance with that is quite universally as far as I'm told by
controllers. :-)

The AIM is available on line. Look at www.faa.gov for the publications.
It is not regulatory, but its procedures are generally followed.

Thanks!


Best regards,
Daniel

On Mon, 28 Nov 2005 06:35:53 +0000 (UTC), Daniel Roesen wrote:

Well, what other interpretations of "optimum rate of descend" would
you have in mind? I

I would take it to mean that you take into account all the factors
involved, not just how much money you're going to spend/save. That would
include, but not be limited to, operating characteristics of the aircraft,
passenger comfort, ATC expectations, expense, visibility at the required
angle of attack, etc.

For example, in my Mooney, I would typically use a cruise climb of 115-120
KIAS rather than a best rate of climb of about 90 KIAS because of improved
forward visibility at the lower AOA (unless ATC requested "best rate").




Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Well, what other interpretations of "optimum rate of descend" would
you have in mind?

Depends what one is trying to optimize. Money, turbulence, time
enroute, arrival time (to coincide with an open gate), dive currency,
there are many things that one can attempt to "optimize", though I'd
agree that ATC is not likely to think of them all.

Jose
--
You can choose whom to befriend, but you cannot choose whom to love.
for Email, make the obvious change in the address.

"Daniel Roesen" wrote in message
...
* Ron Rosenfeld :
Hm... interesting. "optimum rate consistent with the operating
characteristics of the aircraft". This is fuzzy.

Nothing wrong with giving the pilot discretion over the rate of descent.
However, there is a requirement to notify ATC if climb/descent rates
will
be less than 500 fpm.

OK, that makes sense. Never heard of that requirement yet, thanks for
that. Will check our regulations here about comparable requirements.

You seem to be defining "optimum" as equivalent to "economic". I see no
such implication in the US.

Well, what other interpretations of "optimum rate of descend" would
you have in mind? If they didn't have anything specific in mind, they
could have written "any rate consistent with the operating
characteristics". Which would be kinda superfluous as you should never
climb/descend with a rate not being consistent with the operating
characteristics.

I believe FAAO 7110.183 has all the performance expectations for various
aircraft from ATC's perspective. Good luck finding it.. I have a 6 year old
version and cant find it online right now.




--
Mike Teague - Vancouver WA, USA
-- Opie and Anthony - XM202 - O&A Party Rock!
-- Phil Hendrie = Radio Genius

"Mike Teague" wrote in message
news
"Daniel Roesen" wrote in message
...
* Ron Rosenfeld :
Hm... interesting. "optimum rate consistent with the operating
characteristics of the aircraft". This is fuzzy.

Nothing wrong with giving the pilot discretion over the rate of
descent.
However, there is a requirement to notify ATC if climb/descent rates
will
be less than 500 fpm.

OK, that makes sense. Never heard of that requirement yet, thanks for
that. Will check our regulations here about comparable requirements.

You seem to be defining "optimum" as equivalent to "economic". I see
no
such implication in the US.

Well, what other interpretations of "optimum rate of descend" would
you have in mind? If they didn't have anything specific in mind, they
could have written "any rate consistent with the operating
characteristics". Which would be kinda superfluous as you should never
climb/descend with a rate not being consistent with the operating
characteristics.

I believe FAAO 7110.183 has all the performance expectations for various
aircraft from ATC's perspective. Good luck finding it.. I have a 6 year
old
version and cant find it online right now.



Ahh, I found it, sorry, it's now appendix A in the 7110.65.

--
Mike Teague - Vancouver WA, USA
-- Opie and Anthony - XM202 - O&A Party Rock!
-- Phil Hendrie = Radio Genius

Mike Teague wrote:
"Mike Teague" wrote in message
news
"Daniel Roesen" wrote in message
...
* Ron Rosenfeld :
Hm... interesting. "optimum rate consistent with the operating
characteristics of the aircraft". This is fuzzy.

Nothing wrong with giving the pilot discretion over the rate of
descent.
However, there is a requirement to notify ATC if climb/descent rates
will
be less than 500 fpm.

OK, that makes sense. Never heard of that requirement yet, thanks for
that. Will check our regulations here about comparable requirements.

You seem to be defining "optimum" as equivalent to "economic". I see
no
such implication in the US.

Well, what other interpretations of "optimum rate of descend" would
you have in mind? If they didn't have anything specific in mind, they
could have written "any rate consistent with the operating
characteristics". Which would be kinda superfluous as you should never
climb/descend with a rate not being consistent with the operating
characteristics.

I believe FAAO 7110.183 has all the performance expectations for various
aircraft from ATC's perspective. Good luck finding it.. I have a 6 year
old
version and cant find it online right now.



Ahh, I found it, sorry, it's now appendix A in the 7110.65.

--
Mike Teague - Vancouver WA, USA
-- Opie and Anthony - XM202 - O&A Party Rock!
-- Phil Hendrie = Radio Genius
You like Phil Hendrie too?

"Herb Sewell" wrote in message
oups.com...

You like Phil Hendrie too?



obviously.. heard from walter bellhaven lately? I hear he is doing lectures
on botany in the day-room these days


--
Mike Teague - Vancouver WA, USA
-- Opie and Anthony - XM202 - O&A Party Rock!
-- Phil Hendrie = Radio Genius