Barometer Setting in Europe question...

Here in the US, the barometer setting used is either the local setting when below 18,000'
MSL or 29.92 when at or above 18,000' MSL. This is according to FAR 91.81.

My question is on understanding how this works in Europe (and other airspaces
besides the US). My current hazy knowledge is that the 18000 feet may be different
either by country or some other boundary. Could someone familiar with this crossover
in Europe or elsewhere advise me on how it works?

Thanks in Advance!

is that in Europe

[Stefan]

wrote:

> My question is on understanding how this works in Europe (and other airspaces

It differs vastly from country to country. As airspace structure does, BTW.

Basically, there are three settings: QNE, QNH and QFE. Yes, those
Q-codes are used in radio communications (as well as in printed material).

QNE means 1013.2 (i.e. 29.92). You set it above a certain altitude,
which differs from county to country, or above the transition altitude
at controlled airports, in which case the transition altitude is
published. On some airports it stays the same all the time, on other
airports it varies.

Below this altitude, you set either QNH (altitude above MSL) or QFE
(altitude above airport level). Again, this varies from one place to
another.

Sounds confusing? You get used to it.

Stefan

[john smith]

Thanks Stefan.
That's the simplest explanation I have yet to hear.

Stefan wrote:
> QNE means 1013.2 (i.e. 29.92). You set it above a certain altitude,
> which differs from county to country, or above the transition altitude
> at controlled airports, in which case the transition altitude is
> published. On some airports it stays the same all the time, on other
> airports it varies.
>
> Below this altitude, you set either QNH (altitude above MSL) or QFE
> (altitude above airport level). Again, this varies from one place to
> another.

[Ron McKinnon]

> wrote in message
k.net...
> Here in the US, the barometer setting used is either the local setting
> when below 18,000'
> MSL or 29.92 when at or above 18,000' MSL. This is according to FAR 91.81.
>
> My question is on understanding how this works in Europe (and other
> airspaces
> besides the US).

Canada has a 'Standard Pressure Region', and an 'Altimeter Setting Region'.

The 'Standard Pressure Region' is all airspace over Canada at or above 18000
feet, and all low level airspace that is outside of the lateral limit of the
'altimeter setting region'. (The 'low level airspace that is outside of
the lateral limit of the altimeter setting region' is essentially the arctic
and high arctic.)

While operating in the 'Standard Pressure Region', the altimeter is set to
standard pressure, which is 20.92 In.Hg, or 1013.2 mbs. (Except that for
departures and arrivals the airport altimeter setting is used, when
available, or, for departures with no altimeter setting available, the
elevation of the given airport)

While operating in the low-level airspace in the Altimeter Setting Region,
the altimeter is set to the altimeter setting (if known) of the given
airport for departures and arrivals, and otherwise the nearest station, and
otherwise the station nearest to the route of flight.

[Jackal24]

"Ron McKinnon" > wrote in
news:Q9J2e.858461$8l.285987@pd7tw1no:

> While operating in the 'Standard Pressure Region', the altimeter is
> set to standard pressure, which is 20.92 In.Hg, or 1013.2 mbs.

20.92? Are you inside the eye of a hurricane or something? :)

[Ron McKinnon]

"Jackal24" > wrote in message
...
> "Ron McKinnon" > wrote in
> news:Q9J2e.858461$8l.285987@pd7tw1no:
>
>> While operating in the 'Standard Pressure Region', the altimeter is
>> set to standard pressure, which is 20.92 In.Hg, or 1013.2 mbs.
>
> 20.92? Are you inside the eye of a hurricane or something? :)

Oops! Typo.

[G Farris]

In article >, says...

>
>Sounds confusing? You get used to it.
>

Good post, Stefan.
Sounds confusing? It IS confusing, even when you get used to it.
Having flown both systems, the European system is really a nuisance!
It is (at least theoretically) justified because in Europe, the "general"
18000' altitude would not be sufficient to provide terrain clearance in all
locations, as it is in the US. Therefore, rather than create a special
airspace for the 10 sq-mi area concerned, the entire continent is subjected to
arcane usage rules, with transition altitudes and levels (they are different
when climbing and descending) that vary from day to day, depending on the
barometric pressure, and are different according to whether or not one is in a
TMA or other terminal procedure controlled airspace.

Generally speaking, however, these transitions almost always occur at or below
5500', so it is common to hear aircraft - even VFR - reporting FL5500, for
example.

Fortunately, the use of QFE - once dear to VFR-only pilots - is going by the
wayside. Time was, pilots would set their altimiters to "0" before takeoff,
then "at some point" transition to the local altimeter setting. On VFR
approach, they would set their altimeter to the field elevation, so they could
execute their pattern with the same reference altitudes displayed on their
altimeter, regardless of the actual field elevation. Good idea, I suppose, but
in reality it only added "one more" reference setting to the already thick
soup. This practice appears to be disappearing with the institution of
pan-European flight crew training.

G Faris

[Julian Scarfe]

> wrote in message
k.net...
> Here in the US, the barometer setting used is either the local setting
> when below 18,000'
> MSL or 29.92 when at or above 18,000' MSL. This is according to FAR 91.81.
>
> My question is on understanding how this works in Europe (and other
> airspaces
> besides the US). My current hazy knowledge is that the 18000 feet may be
> different
> either by country or some other boundary. Could someone familiar with this
> crossover
> in Europe or elsewhere advise me on how it works?

That's just about it. Different states set different thresholds (called the
"transition altitude") that are similar in effect to the 18,000 ft. At and
below that altitude a "local setting" is used and the vertical coordinate is
referred to as "altitude". Above that level 1013.25 hPa (= 29.92 inHg) is
used and the vertical coordinate is referred to as "flight level".

In some cases, different areas within states have different transition
altitudes for ATC purposes. For example in the UK, the general transition
altitude is 3000 ft, but within the horizontal extent of the London TMA it
becomes 6000 ft.

Julian Scarfe

[Julian Scarfe]

"Stefan" > wrote in message
...
> wrote:

> QNE means 1013.2 (i.e. 29.92).

This is actually a misconception, though a very commonly held one. When QNE
was used in RT, it represented the *elevation* that would be measured on an
altimeter set to 1013.2 at a reference station (usually an airport). Thus a
sea level airport with QNH 1010 hPa would report a QNE of approx 90 ft.

Q-codes generally represented questions and answers. "What is the standard
atmospheric pressure?" is a question with a predictable answer. ;-)

QNE no longer appears on the ICAO list of abbreviations and codes, so I
guess the distinction is of academic interest only.

Julian Scarfe

[Stefan]

Julian Scarfe wrote:

> This is actually a misconception, though a very commonly held one. When QNE
> was used in RT, it represented the *elevation* that would be measured on an

I suspect you'll find even more inaccuracies in my post if you really go
for it. (The omission to point out the difference between transition
altitude and transition level jumps to my mind.) I tried to keep it simple.

A good list of the exact definitions of all Q-codes is here:
http://www.kloth.net/radio/qcodes.php

Of allthose codes, the ones I think a pilot should (must) know are
QNE, QNH, QFE (in Europe, at least)
QFU (you'll find that on french approach plates, for example)
QDR, QDM, QTE (not good if you're lost and then confuse QDR and QDM)

Stefan

[Stefan]

G Farris wrote:

> Sounds confusing? It IS confusing, even when you get used to it.

Frankly, I think street traffic rules are more comlicated. But you
really must do your homework before you o to a place (or even a country)
you've never been before.

> Having flown both systems, the European system is really a nuisance!
> It is (at least theoretically) justified because in Europe, the "general"
> 18000' altitude would not be sufficient to provide terrain clearance in all

I don't think this is the main reason. The real reason is that there are
many independant countries here, each with its own regulation. Of
course, each country has its own idea what a good regulation should look
like. Simple (or comlicated) as that.

Stefan

[[email protected]]

Stefan wrote:
>> QDR, QDM, QTE (not good if you're lost and then confuse QDR and QDM)
>
Not if you have enough fuel, you get there after a while ;-)
-Kees

[Markus Voget]

wrote:
> Stefan wrote:
>>> QDR, QDM, QTE (not good if you're lost and then confuse QDR and QDM)
> Not if you have enough fuel, you get there after a while ;-)

Not a problem, as long as you are Steve Fossett... :-)


Greetings,
Markus

[Dylan Smith]

In article >, Julian Scarfe wrote:
> In some cases, different areas within states have different transition
> altitudes for ATC purposes. For example in the UK, the general transition
> altitude is 3000 ft, but within the horizontal extent of the London TMA it
> becomes 6000 ft.

And, if I remember correctly, for VFR in most instances you can fly
altitude rather than flight level (but when you talk to ATC it's
important to make the distinction). For example, going home the other
day, I was flying altitude 4000 over the Pennines, but didn't change to
flight levels once over the Irish Sea now I was over 3000' AGL - I just
told Ronaldsway I was 'altitude 4000' when I checked in with them.

--
Dylan Smith, Castletown, Isle of Man
Flying: http://www.dylansmith.net
Frontier Elite Universe: http://www.alioth.net
"Maintain thine airspeed, lest the ground come up and smite thee"

[Julian Scarfe]

"Dylan Smith" > wrote in message
...
>
> And, if I remember correctly, for VFR in most instances you can fly
> altitude rather than flight level (but when you talk to ATC it's
> important to make the distinction). For example, going home the other
> day, I was flying altitude 4000 over the Pennines, but didn't change to
> flight levels once over the Irish Sea now I was over 3000' AGL - I just
> told Ronaldsway I was 'altitude 4000' when I checked in with them.

That's correct, for the UK at least. There's no requirement for VFR flights
to cruise at particular levels, so there's not much point in insisting that
VFR flights use a particular altimeter setting, outside controlled airspace.
However they are "encouraged" to set 1013 above the TA and use quadrantal
levels.

Julian Scarfe

[ShawnD2112]

Not disappearing at all in the UK. QFE is still taught and the numbers are
given every time a pilot calls up an airfield for landing information.

Having trained in the US, I thought QFE/QNH was just the most absurd thing
I'd ever heard. But when you fly in the south of England where the highest
point is usually less than 500 ASL, it's actually not a bad way to do it. I
kind of like the QFE reference because, once I've set the altimeter on the
approach to the pattern, it's one less piece of mental gymnastic work I have
to do.

Transition height in the UK, by the way, is 3,500 ft.

Shawn
"G Farris" > wrote in message
...
> In article >, says...
>
>>
>>Sounds confusing? You get used to it.
>>
>
> Good post, Stefan.
> Sounds confusing? It IS confusing, even when you get used to it.
> Having flown both systems, the European system is really a nuisance!
> It is (at least theoretically) justified because in Europe, the "general"
> 18000' altitude would not be sufficient to provide terrain clearance in
> all
> locations, as it is in the US. Therefore, rather than create a special
> airspace for the 10 sq-mi area concerned, the entire continent is
> subjected to
> arcane usage rules, with transition altitudes and levels (they are
> different
> when climbing and descending) that vary from day to day, depending on the
> barometric pressure, and are different according to whether or not one is
> in a
> TMA or other terminal procedure controlled airspace.
>
> Generally speaking, however, these transitions almost always occur at or
> below
> 5500', so it is common to hear aircraft - even VFR - reporting FL5500,
> for
> example.
>
> Fortunately, the use of QFE - once dear to VFR-only pilots - is going by
> the
> wayside. Time was, pilots would set their altimiters to "0" before
> takeoff,
> then "at some point" transition to the local altimeter setting. On VFR
> approach, they would set their altimeter to the field elevation, so they
> could
> execute their pattern with the same reference altitudes displayed on their
> altimeter, regardless of the actual field elevation. Good idea, I suppose,
> but
> in reality it only added "one more" reference setting to the already thick
> soup. This practice appears to be disappearing with the institution of
> pan-European flight crew training.
>
> G Faris
>

[Dylan Smith]

In article >, ShawnD2112 wrote:
> Not disappearing at all in the UK. QFE is still taught and the numbers are
> given every time a pilot calls up an airfield for landing information.

The one time I like QFE is when towing gliders. Never going more than a
couple of miles from the field, so I always set QFE.

Pretty much any time anyone gives it to me otherwise, I tend not to
bother though.

[Stefan]

Dylan Smith wrote:

> The one time I like QFE is when towing gliders. Never going more than a
> couple of miles from the field, so I always set QFE.

The only case, but then consequently, we use QFE here is when doing
aerobatics.

On tow it's nice when both pilots speak the same language. Ok, there's
already knots vs km/h and feet vs meters, so I guess I could get used to
the QFE vs QNH conversion, too.

Stefan

[Julian Scarfe]

"ShawnD2112" > wrote in message
...
> Not disappearing at all in the UK. QFE is still taught and the numbers
> are given every time a pilot calls up an airfield for landing information.

What you say is true enough, but I get the impression that there are very
few commercial operators who still use QFE, and fewer PPL with instrument
ratings who use it. IMHO, the sooner it's confined to the history books the
better.

Julian Scarfe

[ShawnD2112]

Whatever. Airlines probably don't use it, not that many UK PPLs with
instrument ratings.

Shawn
"Julian Scarfe" > wrote in message
...
> "ShawnD2112" > wrote in message
> ...
>> Not disappearing at all in the UK. QFE is still taught and the numbers
>> are given every time a pilot calls up an airfield for landing
>> information.
>
> What you say is true enough, but I get the impression that there are very
> few commercial operators who still use QFE, and fewer PPL with instrument
> ratings who use it. IMHO, the sooner it's confined to the history books
> the better.
>
> Julian Scarfe
>
>