Confusion about when it's my navigation, and when it's ATC

"Larry Dighera" wrote in message
...
On Wed, 03 Jan 2007 15:35:41 +0100, Mxsmanic
wrote in :

I fly [MS FlightSimulator] from KLAX to KLAS, using the FMC to handle
most of the flight.

Good morning ladies and gentlemen and welcome to Imaginary Airlines. Sorry
for the delay in departure, but we had some technical difficulties with the
PC and had to reboot from a "blue screen of death". Everything is normal
now and we should be departing as soon as I give myself clearance and hit
the bathroom. Oops, wait a minute, I think I hear the telephone ringing...
Sorry again for the delay - that was my ex-girlfriend and the conversation
got a little terse. I also took the opportunity to make a sandwich and pop
open a brewski. On climbout be sure to look down and notice the beautiful
parquee floor below us. Those of you fortunate enough to be seated on the
right side of the room will have a fantastic view of the door to the bath
room. As long as the power stays on and this #$&@# windows PC behaves we
should be arriving on time. Thanks again for flying Imaginary Airlines, we
hope to see you back again soon...

"BDS" wrote in message
et...
"Larry Dighera" wrote in message
...
On Wed, 03 Jan 2007 15:35:41 +0100, Mxsmanic
wrote in :

I fly [MS FlightSimulator] from KLAX to KLAS, using the FMC to handle
most of the flight.

Good morning ladies and gentlemen and welcome to Imaginary Airlines.
Sorry
for the delay in departure, but we had some technical difficulties with
the
PC and had to reboot from a "blue screen of death". Everything is normal
now and we should be departing as soon as I give myself clearance and hit
the bathroom. Oops, wait a minute, I think I hear the telephone
ringing...
Sorry again for the delay - that was my ex-girlfriend and the conversation
got a little terse. I also took the opportunity to make a sandwich and
pop
open a brewski. On climbout be sure to look down and notice the beautiful
parquee floor below us. Those of you fortunate enough to be seated on the
right side of the room will have a fantastic view of the door to the bath
room. As long as the power stays on and this #$&@# windows PC behaves we
should be arriving on time. Thanks again for flying Imaginary Airlines,
we
hope to see you back again soon...



Seems about right to me.

----------------------------------------
DW

Mxsmanic,

I fly from KLAX to KLAS


No, you don't. For the sake of those reading here that haven't
discovered your background, please state clearly that you are playing
MS FS.

--
Thomas Borchert (EDDH)

Thomas Borchert writes:

No, you don't.

I did so last night. Today, at least thus far, it was Chandler to
Sedona, and then back from Sedona to Phoenix.

For the sake of those reading here that haven't
discovered your background, please state clearly that you are playing
MS FS.

Why? Most people don't have a phobia of simulation, and for things
like instrument flight and ATC, simulation isn't different enough from
real life to matter for most of the major concepts of both. In
domains where I suspect there may be a discrepancy, I ask for
clarification, which is why I'm here.

--
Transpose mxsmanic and gmail to reach me by e-mail.

Mxsmanic,

Why? Most people don't have a phobia of simulation, and for things
like instrument flight and ATC, simulation isn't different enough from
real life to matter for most of the major concepts of both.


Jeeze, not always the same again.

Your description of your "flight" would never, ever happen in the real
world (which, BTW, means that you statement about the differences
between sim and RL is complete, utter BS). Thus, if you really want
people to react in a sensible way, you need to provide the context,
which is simming. If you don't, people won't understand your post in the
least bit.

Since you have been made aware of this problem in your posts several
times, the only logical conclusion is that you are not interested in
sensible reactions. That's why people conclude you're a troll, not
someone asking for clarification.

--

Thomas Borchert (EDDH)

Thomas Borchert writes:

Your description of your "flight" would never, ever happen in the real
world (which, BTW, means that you statement about the differences
between sim and RL is complete, utter BS).

Which aspect of the flight was unlike the real world?

As I recall, I started at gate 35 at KLAX, was cleared to KLAS with
LOOP4 DAG KEPEC1 at FL290, left on 24L (which is right behind the
gate), and proceeded more or less uneventually to KLAS, with a few
minor modifications to my route from ATC along the way. I did have to
fight with the autopilot and FMS on the way in to KLAS, but only
because I'm not that experienced with them yet. I'm getting better.
In particular, I'm slowly figuring out how to change things en route
so that I can adapt to instructions from ATC, instead of being
compelled to let the FMS fly the entire route as originally entered.
As I get used to it, I like the FMS more than I did at first.

Thus, if you really want people to react in a sensible way, you need
to provide the context, which is simming.

Which part of the above doesn't happen in real life?

If you don't, people won't understand your post in the least bit.

They seem to have understood it without any difficulty.

Since you have been made aware of this problem in your posts several
times, the only logical conclusion is that you are not interested in
sensible reactions.

No. Another, more probable possibility is that it's not a problem to
begin with, except in your own perception, which is not universal.

That's why people conclude you're a troll, not someone asking
for clarification.

Virtually no one has reached this conclusion, apart from a vocal
minority that finds me irritating. It's unfortunate that I end up
explaining this to that minority in almost every thread in which I
participate. If they would just stick to the topic, things would go
much better for all.

--
Transpose mxsmanic and gmail to reach me by e-mail.

Mxsmanic wrote:
Which aspect of the flight was unlike the real world?

You never left the ground?

"Mxsmanic" wrote in message
Now, my question is this: If the FMC has a programmed descent in its
route, do I let the FMC start the descent where it sees fit, or do I
force the aircraft to maintain FL290 until ATC explicitly clears me
for my own navigation or for a lower altitude?

The profile in the FMS is for efficiency and does not take other traffic
into account. You must wait until ATC explicitely clears you to another
altitude. If you are about to pass the FMS's descent point, politely prompt
ATC for a lower altitude. Going into LAS, you very well may get vectors off
the planned route so that ATC can adequately space the arrival traffic (in
the real world).

And if ATC's last
instruction had simply been "resume own navigation" or "proceed as
filed," would that mean that I'd be free to begin the descent whenever
the FMC (or I) decides it's best?

No. That would be for lateral navigation only unless explicitely cleared for
different altitudes. Here is an example that one of my colleagues recently
received counseling about. He was cleared via the KORRY 3 arrival into KLGA.
He started to descend according to the profile. ATC asked why he was
descending and to call a number after landing (not good). He was cleared via
the KORRY 3, not cleared to descend via the KORRY 3. Slight difference, but
very important for traffic seperation.

In situations where I can begin the descent at my discretion (assuming
that own navigation implies this), should I tell ATC that I'm leaving
my cruise altitude?

Yes, the Aeronautical Information Manual states that a pilot should advise
when leaving an altitude.

If the FMC has a continuously changing estimate
of lower altitudes in the descent profile, what should I give as my
target altitude? The next fix that has a specific altitude? (Such as
a fix in the arrival procedure)

Yes.

Climbing I think I understand. If I'm told to resume own navigation,
or cleared as filed in the first place, I climb per my flight plan/FMC
profile. If ATC says maintain X, I stay at X until ATC tells me to
resume own navigation or instructs me to change altitudes. But the
descent part still has me a bit confused.

Query ATC for the assigned altitude so that both of you are on the same
page. Climbs are the same as descents. 'resume own navigation' is for
lateral flight. Don't climb unless expicitely assigned a new altitude by
ATC.

D.

Capt.Doug writes:

The profile in the FMS is for efficiency and does not take other traffic
into account. You must wait until ATC explicitely clears you to another
altitude.

So it would probably be best to set the MCP to prevent any descent
until I'm cleared, then?

If you are about to pass the FMS's descent point, politely prompt
ATC for a lower altitude.

"Request descent," or something, I presume.

Going into LAS, you very well may get vectors off
the planned route so that ATC can adequately space the arrival traffic (in
the real world).

In simulation, too, even though traffic is sometimes too light to
justify it (the ATCs need practice as well). In fact, it seems that I
almost never follow the arrival procedure as published. Often just as
I'm beginning it, ATC gives me other instructions. I suppose it's a
bit of a relief as then all I have to do is follow their instructions,
rather than try to follow the arrival chart (but if the FMC is doing
it, it's easy).

No. That would be for lateral navigation only unless explicitely cleared for
different altitudes.

Is there a specific phrasing that means "you can do your own lateral
AND vertical navigation"? Or does ATC as a rule never let IFR flights
select their own altitudes?

Here is an example that one of my colleagues recently
received counseling about. He was cleared via the KORRY 3 arrival into KLGA.
He started to descend according to the profile. ATC asked why he was
descending and to call a number after landing (not good). He was cleared via
the KORRY 3, not cleared to descend via the KORRY 3. Slight difference, but
very important for traffic seperation.

Hmm. I just assumed that since the plates usually indicate altitudes,
"cleared via the KORRY 3" would necessarily mean following both the
course and altitude indications. What does ATC say if they want you
to follow everything on the plate, including the indicated altitudes?

Did your colleague get into significant trouble?

Yes, the Aeronautical Information Manual states that a pilot should advise
when leaving an altitude.

OK.

Yes.

OK, so should I say something like "leaving FL290 for 12000 at CLARR,"
assuming I'm already cleared to descend at my discretion?

Query ATC for the assigned altitude so that both of you are on the same
page. Climbs are the same as descents. 'resume own navigation' is for
lateral flight. Don't climb unless expicitely assigned a new altitude by
ATC.

So there is no equivalent of "resume own navigation" for altitude,
like "resume own altitude," or whatever?

If ATC regularly overrides the plates and (apparently) doesn't often
clear anyone to follow the altitude indications on the plates, why do
all the approach plates seem to mention altitudes? Just for radio
loss? (Except they often seem to have separate procedures for
communications loss.)

--
Transpose mxsmanic and gmail to reach me by e-mail.

"Mxsmanic" wrote in message
So it would probably be best to set the MCP to prevent any descent
until I'm cleared, then?

MCP = max continuous power? Sorry- not familiar with the term as used on an
FMS. The important thing is to not set the altitude hold for descent until
cleared by ATC.

In simulation, too, even though traffic is sometimes too light to
justify it (the ATCs need practice as well). In fact, it seems that I
almost never follow the arrival procedure as published. Often just as
I'm beginning it, ATC gives me other instructions. I suppose it's a
bit of a relief as then all I have to do is follow their instructions,
rather than try to follow the arrival chart (but if the FMC is doing
it, it's easy).

A good center controller will have all of the arrivals spaced like pearls
before everyone hits the arrival's gate. That way everyone can follow the
arrival as charted with ATC isssuing speed changes to maintain spacing.

Is there a specific phrasing that means "you can do your own lateral
AND vertical navigation"? Or does ATC as a rule never let IFR flights
select their own altitudes?

The most common is a clearance to cross a fix at an assigned altitude
(crossing restriction). Say for example you are cruising at FL290 and the
controller isues you a clearance to cross a fix at 12000'. It is your
perogative as to when to start your descent so long as you cross the fix at
the assigned altitude.

During the climb, ATC sees the final altitude we requested on our flight
plan. They try to get us up there, traffic permitting. After that we request
from ATC any altitude changes we want and they work us to that altitude,
traffic permitting.

What does ATC say if they want you
to follow everything on the plate, including the indicated altitudes?

"DESCEND via the Korry 3"

Did your colleague get into significant trouble?

No, because seperation wasn't lost.

OK, so should I say something like "leaving FL290 for 12000 at CLARR,"
assuming I'm already cleared to descend at my discretion?

Sounds professional.

So there is no equivalent of "resume own navigation" for altitude,
like "resume own altitude," or whatever?

In the IFR world, altitude is all important. There are crossing restrictions
and block altitudes, but most of the time we follow

If ATC regularly overrides the plates and (apparently) doesn't often
clear anyone to follow the altitude indications on the plates, why do
all the approach plates seem to mention altitudes? Just for radio
loss?

In the real world we usually follow the arrival procedures with the
altitudes as published. When flying the big jets, just remember that you
will need 3 miles for every 1000' you want to descend plus another 5 miles
to slow for the 250 knot speed restriction at 10000'.

D.