max altitude deviation before bust?

I thought it was +/- 200 feet before you've violated if you are flying
IFR, but someone just told me it's a 100 feet, which seems a little
steep considering they use 1000 feet separations.

It's +/-100 feet, which is a total range for 200 ft.

Jose

--
(for Email, make the obvious changes in my address)

Why do you say "a little steep?" Clearly if you understand what is going on
there would not be a question. (assuming US/FAA)

vfr traffic 500 feet above/below
altimeter error allowed - 75 feet.
deviation of 100 feet
deviation of VFR traffic - 100 ft

Add up those errors and you have only 150 ft of separation



"Magnus" wrote in message
...
I thought it was +/- 200 feet before you've violated if you are flying
IFR, but someone just told me it's a 100 feet, which seems a little
steep considering they use 1000 feet separations.

"Teacherjh" wrote in message It's +/-100 feet, which is a total range for
200 ft.

I was taught that it was +/- 300 feet and you violated seperation standards
with another IFR target. What is your reference?

D.

Where can you read about the +/- 100 feet, I couldn't find it in the far-aim.


On 2004-03-20 21:44:58 -0500, "Richard Hertz"
said:

Why do you say "a little steep?" Clearly if you understand what is going on
there would not be a question. (assuming US/FAA)

vfr traffic 500 feet above/below
altimeter error allowed - 75 feet.
deviation of 100 feet
deviation of VFR traffic - 100 ft

Add up those errors and you have only 150 ft of separation

"Magnus" wrote in message
...

I thought it was +/- 200 feet before you've violated if you are flying
IFR, but someone just told me it's a 100 feet, which seems a little
steep considering they use 1000 feet separations.


Depends what you mean by "violated". If your Mode C altitude is within 200
feet of your reported altitude you're considered to be on altitude.

"Teacherjh" wrote in message
It's +/-100 feet, which is a total range for
200 ft. [for IFR flight tolerances]

I was taught that it was +/- 300 feet and you violated seperation standards
with another IFR target. What is your reference?


It's what I was taught. I think it's also in the PTS for instrument flight
(though I don't have one handy). I haven't found it in a printed reference.

Jose

--
(for Email, make the obvious changes in my address)

"Richard Hertz" wrote
Add up those errors and you have only 150 ft of separation

When is IFR traffic required to have separation from VFR?

Bob Moore

That's exactly what I'm talking about. My understanding was that if you
have been cleared to maintain 3000 feet, and you dip down for example
past 2800' then it's a violation. A friend heard that it's actually 100
feet, which would incur a violation passing 2900 feet going by my
previous example.

Is there some reliable source of information where this info can be found?

On 2004-03-20 22:16:00 -0500, "Steven P. McNicoll"
said:


Depends what you mean by "violated". If your Mode C altitude is within 200
feet of your reported altitude you're considered to be on altitude.

ATC radar's (at least they used to when I was working them) show you on
"assigned altitude" when you are within +/-200ft.. so if you are assigned
9000 it will say "90C"... if you are still climbing to that altitude it will
say 90 "up-arrow" 87, or 8700 climbing to 9000 assigned.

the "traffic alert" on the ATC system is geared to the 90C, if you are at
9300 it will show 90 "arrow" 93 and if there is a traffic conflict at 10,000
it will "alert" the controller.

Then he may "bust you", but if it's a momentary deviation and no other
traffic is involved, the controller may query and ask your altitude to
verify that his read out is correct. If you say, level 90, Then he may offer
up a new altimeter setting to you, or just tell you that he sees 9300, as a
hint that he is watching, or that you need to get it looked at. If your
altimeter setting is not set to "local", his computer radar will
misinterpret the altitude ModeC information from your aircraft.

All controllers verify altitude readouts on the radar display on initial
contact, whether you call in, "out of 8500 for 9000" or, "level 9000", he
compares to what he sees on his data. If you do not offer up an altitude, or
in the case of an "IFR pickup" in the air, he will ask altitude leaving or
verify alt so he can compare his data.

BT

"Magnus" wrote in message
...
I thought it was +/- 200 feet before you've violated if you are flying
IFR, but someone just told me it's a 100 feet, which seems a little
steep considering they use 1000 feet separations.