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EDR
January 8th 04, 09:46 PM
When filling IFR, there are two boxes you put numbers in, AIRSPEED and
TIME ENROUTE.

These go back to the old days, but are still applicable today.
AIRSPEED, as the name implies, tells ATC how fast your airplane is
going through the air.
TIME ENROUTE tells ATC when to expect you at your destination.

One of the regs says that you have to advice ATC of any airspeed
deviations of +/- 10% (someone correct me if I am wrong, I do not have
the AIM in front of me).
However, the TIME ENROUTE should take into account headwinds and/or
tailwinds. This is important in the event of loss of comm.

Here is the question:
When you fill in the AIRSPEED box, do you give the actual indicated
airspeed for your cruise power setting?
Or, do you use the "groundspeed", based on winds aloft?

If you use the actual indicated airspeed, the math is not correct for
the time enroute.

If you use the actual airspeed and the calculated no-wind time enroute,
you mess up the system in the event of loss of comm, since you will not
be where they expect you in the elapsed time.

Further, in these days of RADAR, LORAN and GPS, do you advice ATC of
the groundspeed deviation from the airspeed?

Bob Gardner
January 8th 04, 09:52 PM
From the AIM: "Block 4: Enter your true airspeed (TAS)"

Don't sweat the details.

Bob Gardner

"EDR" > wrote in message
...
>
> When filling IFR, there are two boxes you put numbers in, AIRSPEED and
> TIME ENROUTE.
>
> These go back to the old days, but are still applicable today.
> AIRSPEED, as the name implies, tells ATC how fast your airplane is
> going through the air.
> TIME ENROUTE tells ATC when to expect you at your destination.
>
> One of the regs says that you have to advice ATC of any airspeed
> deviations of +/- 10% (someone correct me if I am wrong, I do not have
> the AIM in front of me).
> However, the TIME ENROUTE should take into account headwinds and/or
> tailwinds. This is important in the event of loss of comm.
>
> Here is the question:
> When you fill in the AIRSPEED box, do you give the actual indicated
> airspeed for your cruise power setting?
> Or, do you use the "groundspeed", based on winds aloft?
>
> If you use the actual indicated airspeed, the math is not correct for
> the time enroute.
>
> If you use the actual airspeed and the calculated no-wind time enroute,
> you mess up the system in the event of loss of comm, since you will not
> be where they expect you in the elapsed time.
>
> Further, in these days of RADAR, LORAN and GPS, do you advice ATC of
> the groundspeed deviation from the airspeed?

Jim
January 8th 04, 10:46 PM
TAS.
I always tell myself they need to know it for spaceing me between the big
boys.... just so I don't run them over. :))
--
Jim Burns III

Remove "nospam" to reply

Paul Tomblin
January 8th 04, 10:46 PM
In a previous article, EDR > said:
>Here is the question:
>When you fill in the AIRSPEED box, do you give the actual indicated
>airspeed for your cruise power setting?
>Or, do you use the "groundspeed", based on winds aloft?
>
>If you use the actual indicated airspeed, the math is not correct for
>the time enroute.

They don't want the AIRSPEED so they can check your math, they want it for
separation purposes.


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Robert Moore
January 8th 04, 10:51 PM
EDR > wrote

Gee...EDR, you really disappoint me. :-)

> One of the regs says that you have to advice ATC of any airspeed
> deviations of +/- 10% (someone correct me if I am wrong,

Well, you asked for it! Advice is a noun. The word that you wanted
to use is advise, the verb.

> When you fill in the AIRSPEED box, do you give the actual indicated
> airspeed for your cruise power setting?

Nope! You use TAS, which is CAS corrected for pressure altitude and
temperature. Hmmm....how do you get from IAS to CAS???? :-)

> If you use the actual indicated airspeed, the math is not correct for
> the time enroute.

Of course, if you are using indicated airspeed, the math isn't correct
anyway.

> If you use the actual airspeed and the calculated no-wind time enroute,
> you mess up the system in the event of loss of comm, since you will not
> be where they expect you in the elapsed time.

If you have "advised" ATC of a change in TAS, they recompute your ETA.


> Further, in these days of RADAR, LORAN and GPS, do you advice ATC of
> the groundspeed deviation from the airspeed?

EDR....you really aren't a pilot are you?

Bob Moore
ATP CFI

Newps
January 9th 04, 01:25 AM
Robert Moore wrote:

>
> If you have "advised" ATC of a change in TAS, they recompute your ETA.

ATC does no such thing. You tell a controller that you are going 20
knots slower/faster than you put on your flight plan the controller
could not possibly care less. In one ear and out the other.

Newps
January 9th 04, 01:29 AM
Paul Tomblin wrote:


> They don't want the AIRSPEED so they can check your math, they want it for
> separation purposes.

That's what they tell you. If you lose comm but your transponder still
works life is golden for the controller. Lose the transponder too and
we'll use primary radar, although that makes the workload for the
controller go up significantly. Lose radar and ATC will essentially
clear a route for you. But no way, no how will the controllers call
AFSS, get your filed airspeed and/or ETE and simply wait for that time
to pass before resuming normal operations. Normal ops will not commence
until we know where you are.

john smith
January 9th 04, 02:01 AM
Robert Moore wrote:
> Gee...EDR, you really disappoint me. :-)

Stuff happens!

> > One of the regs says that you have to advice ATC of any airspeed
> > deviations of +/- 10% (someone correct me if I am wrong,
>
> Well, you asked for it! Advice is a noun. The word that you wanted
> to use is advise, the verb.

I knew that! I didn't catch it, but I see the online service did.

> > When you fill in the AIRSPEED box, do you give the actual indicated
> > airspeed for your cruise power setting?
>
> Nope! You use TAS, which is CAS corrected for pressure altitude and
> temperature. Hmmm....how do you get from IAS to CAS???? :-)

Nice catch! All these years I never noticed it was TRUE airspeed in
block 4. I have always used indicated. Oh well, that's what the whiz
wheel is for, isn't it?

> EDR....you really aren't a pilot are you?

I prefer to think of myself as an "aviator". I chalk it up to a 15 year
layoff of IFR flying. 1200 hours, 400 in a 1945 Champ, doesn't give me
much practice.

Craig Prouse
January 9th 04, 02:11 AM
In article <aqnLb.1278$na.1288@attbi_s04>, Newps >
wrote:

> Robert Moore wrote:
>
> >
> > If you have "advised" ATC of a change in TAS, they recompute your ETA.
>
> ATC does no such thing. You tell a controller that you are going 20
> knots slower/faster than you put on your flight plan the controller
> could not possibly care less. In one ear and out the other.


Don Brown, according to his column today, seems to pay attention to such
details.

http://www.avweb.com/news/columns/186442-1.html

David Brooks
January 9th 04, 02:12 AM
"Newps" > wrote in message
news:aqnLb.1278$na.1288@attbi_s04...
>
>
> Robert Moore wrote:
>
> >
> > If you have "advised" ATC of a change in TAS, they recompute your ETA.
>
> ATC does no such thing. You tell a controller that you are going 20
> knots slower/faster than you put on your flight plan the controller
> could not possibly care less. In one ear and out the other.

Probably the only person who will care if you don't announce it is the DE on
your instrument checkride. And I don't think they will care very much. (I
did it on my checkride because I slowed to Va (not Vb) for turbulence).

-- David Brooks

Steven P. McNicoll
January 9th 04, 04:46 AM
"EDR" > wrote in message
...
>
> Here is the question:
> When you fill in the AIRSPEED box, do you give the actual indicated
> airspeed for your cruise power setting?
> Or, do you use the "groundspeed", based on winds aloft?
>

Neither, you use true airspeed.


>
> Further, in these days of RADAR, LORAN and GPS, do you advice ATC of
> the groundspeed deviation from the airspeed?
>

No, you advise of changes in your filed true airspeed.

C J Campbell
January 9th 04, 05:46 AM
"Craig Prouse" > wrote in message
...
| In article <aqnLb.1278$na.1288@attbi_s04>, Newps >
| wrote:
|
| > Robert Moore wrote:
| >
| > >
| > > If you have "advised" ATC of a change in TAS, they recompute your ETA.
| >
| > ATC does no such thing. You tell a controller that you are going 20
| > knots slower/faster than you put on your flight plan the controller
| > could not possibly care less. In one ear and out the other.
|
|
| Don Brown, according to his column today, seems to pay attention to such
| details.
|
| http://www.avweb.com/news/columns/186442-1.html

Don Brown's gripe appears to be about what he was handed from other sectors,
not about what airspeed the pilot reported.

Correct me if I am wrong, but I thought you only reported a change in
airspeed or ETA if you were in a non-radar environment?

Stan Gosnell
January 9th 04, 08:51 AM
Newps > wrote in
news:OtnLb.2313$xy6.6588@attbi_s02:

> That's what they tell you. If you lose comm but your
> transponder still works life is golden for the controller.
> Lose the transponder too and we'll use primary radar,
> although that makes the workload for the controller go up
> significantly. Lose radar and ATC will essentially clear a
> route for you.

Radar doesn't cover everywhere, so the old non-radar separation
still has to be used. Where I fly, I'm lucky to get radar
contact for the last 40 miles back in. So how does ZHU provide
the separation, when there are 8 or 10 aircraft on the same
route, inbound and outbound, if they don't have the filed
airspeed? Ouija board? Or just a WAG? Or don't they care? I
don't think it's the last one.

--
Regards,

Stan

ross watson
January 9th 04, 11:06 AM
My instructor told me I had to report change in airspeed regardless. I
found this in the AIM:

Section 3. En Route Procedures

5-3-1. ARTCC Communications

<snip>

5-3-3. Additional Reports

a. The following reports should be made to ATC or FSS facilities
without a specific ATC request:

1. At all times.

(a) When vacating any previously assigned altitude or flight
level for a newly assigned altitude or flight level.

(b) When an altitude change will be made if operating on a
clearance specifying VFR-on-top.

(c) When unable to climb/descend at a rate of a least 500 feet
per minute.

(d) When approach has been missed. (Request clearance for
specific action; i.e., to alternative airport, another approach, etc.)

(e) Change in the average true airspeed (at cruising altitude)
when it varies by 5 percent or 10 knots (whichever is greater) from that
filed in the flight plan.



FWIW

----------------------------------------------------------


"C J Campbell" > wrote in message
...
>
> "Craig Prouse" > wrote in message
> ...
> | In article <aqnLb.1278$na.1288@attbi_s04>, Newps >
> | wrote:
> |
> | > Robert Moore wrote:
> | >
> | > >
> | > > If you have "advised" ATC of a change in TAS, they recompute your
ETA.
> | >
> | > ATC does no such thing. You tell a controller that you are going 20
> | > knots slower/faster than you put on your flight plan the controller
> | > could not possibly care less. In one ear and out the other.
> |
> |
> | Don Brown, according to his column today, seems to pay attention to such
> | details.
> |
> | http://www.avweb.com/news/columns/186442-1.html
>
> Don Brown's gripe appears to be about what he was handed from other
sectors,
> not about what airspeed the pilot reported.
>
> Correct me if I am wrong, but I thought you only reported a change in
> airspeed or ETA if you were in a non-radar environment?
>
>

Steven P. McNicoll
January 9th 04, 12:28 PM
"C J Campbell" > wrote in message
...
>
> Correct me if I am wrong, but I thought you only reported a change in
> airspeed or ETA if you were in a non-radar environment?
>

The AIM says to report at all times a change in the average true airspeed
(at cruising altitude) when it varies by 5 percent or 10 knots (whichever is
greater) from that filed in the flight plan.

Newps
January 9th 04, 03:05 PM
Stan Gosnell wrote:
> Newps > wrote in
> news:OtnLb.2313$xy6.6588@attbi_s02:
>
>
>>That's what they tell you. If you lose comm but your
>>transponder still works life is golden for the controller.
>>Lose the transponder too and we'll use primary radar,
>>although that makes the workload for the controller go up
>>significantly. Lose radar and ATC will essentially clear a
>>route for you.
>
>
> Radar doesn't cover everywhere, so the old non-radar separation
> still has to be used. Where I fly, I'm lucky to get radar
> contact for the last 40 miles back in. So how does ZHU provide
> the separation, when there are 8 or 10 aircraft on the same
> route, inbound and outbound, if they don't have the filed
> airspeed? Ouija board? Or just a WAG? Or don't they care? I
> don't think it's the last one.

The computer spits out strips just like for any flight. These strips are
updated by the controller. Since you are only flying anout 50 miles
nonradar that's probably the same controller, so there's no updating to
do. You are still talking to him and separation is easiest using vertical.

Steven P. McNicoll
January 9th 04, 04:21 PM
"Newps" > wrote in message
news:zqzLb.5797$Rc4.25147@attbi_s54...
>
> The computer spits out strips just like for any flight. These strips are
> updated by the controller. Since you are only flying anout 50 miles
> nonradar that's probably the same controller, so there's no updating to
> do. You are still talking to him and separation is easiest using
vertical.
>

Hmmm..... There are 8 or 10 aircraft on the same route, inbound and
outbound, and you're going to use vertical separation. How are you going to
get the arrivals through the departures?

Mike Rapoport
January 10th 04, 04:14 AM
Since the box says TRUE AIRSPEED, I put true airspeed in the box.

Mike
MU-2

"EDR" > wrote in message
...
>
> When filling IFR, there are two boxes you put numbers in, AIRSPEED and
> TIME ENROUTE.
>
> These go back to the old days, but are still applicable today.
> AIRSPEED, as the name implies, tells ATC how fast your airplane is
> going through the air.
> TIME ENROUTE tells ATC when to expect you at your destination.
>
> One of the regs says that you have to advice ATC of any airspeed
> deviations of +/- 10% (someone correct me if I am wrong, I do not have
> the AIM in front of me).
> However, the TIME ENROUTE should take into account headwinds and/or
> tailwinds. This is important in the event of loss of comm.
>
> Here is the question:
> When you fill in the AIRSPEED box, do you give the actual indicated
> airspeed for your cruise power setting?
> Or, do you use the "groundspeed", based on winds aloft?
>
> If you use the actual indicated airspeed, the math is not correct for
> the time enroute.
>
> If you use the actual airspeed and the calculated no-wind time enroute,
> you mess up the system in the event of loss of comm, since you will not
> be where they expect you in the elapsed time.
>
> Further, in these days of RADAR, LORAN and GPS, do you advice ATC of
> the groundspeed deviation from the airspeed?

Stan Gosnell
January 10th 04, 06:36 AM
Newps > wrote in
news:zqzLb.5797$Rc4.25147@attbi_s54:

> The computer spits out strips just like for any flight.
> These strips are updated by the controller. Since you are
> only flying anout 50 miles nonradar that's probably the
> same controller, so there's no updating to do. You are
> still talking to him and separation is easiest using
> vertical.

It's often more like 200NM nonradar, but it's still often the
same controller. But if he doesn't know the airspeed of any of
the aircraft, how does he insure separation? Running into
another aircraft out there isn't something I want to have to
worry about.

--
Regards,

Stan

Newps
January 11th 04, 10:41 PM
Stan Gosnell wrote:


> It's often more like 200NM nonradar, but it's still often the
> same controller. But if he doesn't know the airspeed of any of
> the aircraft, how does he insure separation?

First off we all know the airspeed of virtually every aircraft we work.
You don't have to know it exactly. Being able to ballpark it is good
enough. Secondly, you are separated vertically if you are close to
someone else.

Steven P. McNicoll
January 12th 04, 03:08 AM
"Newps" > wrote in message
news:FikMb.27443$8H.64079@attbi_s03...
>
> First off we all know the airspeed of virtually every aircraft we work.
> You don't have to know it exactly. Being able to ballpark it is good
> enough. Secondly, you are separated vertically if you are close to
> someone else.
>

I want to land. How are you going to get me through that aircraft below me?

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