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Old 9th Apr 2009, 12:52
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Transition Altitude / Level

Hi All,

I'm trying to find a reference (specifically for European countries) that is clear about the transition altitudes/levels for each memebr state.

In the UK, the transition Altitude is the highest Altitude at which QNH is used as the controlling reference.

I know some states are different, and may refer to the transition altitude as a Flight Level.

Amsterdam appears to be the oddest of all, with different transition altitudes (given by ATIS) on the departure and arrival frequencies at the same time ...

Can anyone shine a light (not a laser)?
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Old 9th Apr 2009, 15:41
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Trans ALT - Trans LVL

As to transition heights, altitudes and levels, each airport arrival, approach and departure chart, or even enroute low altitude maps (I used Jeppesen through my career) specified the applicable "altimeter transition". I have flown worldwide, and never used a "general reference".
xxx
I have seen "transitions altitudes" to be as low as 3,000' QNH, and "transition levels" as low as FL 040 (or possibly even FL 035). I have seen them as high as 20,000' and FL 200, such as in the Mexico FIRs. In Canada and the USA, the "transition altitude" is (everywhere) at 18,000' QNH, and the "transition level" is translated by the wording "lowest usable level" which is FL 180 for QNH at or above 1013.2/29.92 and 500 feet higher (FL 185 or sometimes even FL 190) depending how low the local QNH happens to be below standard.
xxx
Then, many locations publish "transition level by ATC", and is often on ATIS. I recall Hong Kong had a transition level at some FL 120 or 130 with a certain QNH value, and with a lower QNH value, to be 1,000 feet higher.
xxx
My approach/landing briefing to my crew, in the case of "transition level by ATC" not yet received, was to assume it to be 1,000 feet above the "transition altitude published", thereby providing a "transition layer" of some 1,000 feet for most cases. That kept us out of trouble until the actual "transition level" was received on ATIS or by ATC.
xxx
For you in Europe, pay attention to the "transition level" for the Geneva or Milano area, particularly with low QNH and below standard temperatures. It may be darned close to the "granitoculumus" called "the Alps". Same story applies to cross the Andes between Argentina and Chile.
xxx

Happy contrails
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Old 9th Apr 2009, 15:52
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For you in Europe, pay attention to the "transition level" for the Geneva or Milano area, particularly with low QNH and below standard temperatures. It may be darned close to the "granitoculumus" called "the Alps". Same story applies to cross the Andes between Argentina and Chile.
- good advice as always, but I should point out that ATC are required to (and do) adjust minimum allocated Flight Levels to allow for such - that's in Europe, anyway. I don't think that TL will change with low temps, but you should never be cleared to an unsafe level (did I say 'never'....?) and, of course, with QNH on your standby anyway, plus that good old 'situation awareness'......................
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Old 9th Apr 2009, 16:13
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<<In the UK, the transition Altitude is the highest Altitude at which QNH is used as the controlling reference.>>

There's a bit more:

Within the UK:

Transition Altitude
Transition altitude is the altitude at or below which the vertical position of an aircraft is normally controlled by reference to altitude. Wherever possible there is a common transition altitude for aerodromes within a control zone (Eg London TMA it is 6000 ft). Unless otherwise notified the transition altitude for civil aerodromes is 3000 feet.

Transition Level

Transition level is the lowest flight level available for use above the transition altitude.
It is determined by ATC as follows:
a) Within controlled airspace by the controlling authority and it will normally be based on the QNH of the major aerodrome;
b) Outside controlled airspace by the aerodrome authority and based on the
aerodrome QNH.
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Old 9th Apr 2009, 16:17
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BOAC - Just trying to avoid bending some metal...
xxx
You see, long ago, I remember taking off a few times from MXP heading towards the NW, with DC8-61s in dire need of vitamins, and 250 GI passengers with a "10 kg" average carry-on combat kits - at a (supposedly) legal maximum takeoff weight... That radio altimeter (set at 2,500) warning light got me nervous a few times right around Geneva.
xxx
Occasionally (if lucky), we finally reached cruise level at the boundary of Shanwick FIR. The DC8-61 was a "fuel to noise converter" aeroplane. Nothing else beyond that.
xxx

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Old 9th Apr 2009, 17:23
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In Germany:

Transition Altitude always 5000ft.
Transition Level FL60, if QNH below 1013 it is FL70.
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Old 22nd Aug 2010, 14:34
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rather start a new topic...(I did a search!)


So I am getting a bit confused here. A person takes off controller lets say after passing an arbitary figure of 1800 AGL says ' G-ABCD' cleared to climb FL280' I have been shown unless it was uncontrolled airspace / comms failure CHANGE to 1013 straight away. In JAA land of course. Now speaking with an Emirates driver the other day say there ops in Europe and anywhere for that matter is to change withing 1000ft of TA/TL. Ok so now are we all flying on different pressure settings. One is waiting to reach TA , whi,lst another pilot switches straight away - CAP er 413 I did read this ....
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Old 22nd Aug 2010, 14:49
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dd - bear in mind that the aircraft you are talking about are all 'climbing' so there should be no problem if they are on different settings.
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Old 22nd Aug 2010, 14:52
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I agree with RTO.

Why a global TA can't be used is beyond me. It would be far easier to have a standardised TA of FL180 rather than having to fumble around with all of these different TAs for different countries or areas.
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Old 22nd Aug 2010, 15:25
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Thanks BOAC just did a search and looked at a post/ref to the UK AIP thats clears that up you made - well at least the UK shores are clear!

Last edited by dynamite dean; 22nd Aug 2010 at 15:51.
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Old 23rd Aug 2010, 07:11
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I agree with RTO.

Why a global TA can't be used is beyond me. It would be far easier to have a standardised TA of FL180 rather than having to fumble around with all of these different TAs for different countries or areas.
The transition altitude and level is tied in with the local terrain.

Why have a TA of 18,000' in a country with low terrain? In somewhere like Australia there is not much in the way of hills to hit so isn't it best to have as many aircraft as possible flying on 1013 so they don't have to change QNH all the time throughout flight? On the other hand a country like the USA needs a high transition altitude because they have much higher terrain and you don't want pilots getting caught out flying on 1013 when the QNH is 885 and losing terrain separation. A LSALT is not very meaningful if it is expressed as a Flight Level!
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Old 23rd Aug 2010, 09:02
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Aviophage:

Why a global TA can't be used is beyond me. It would be far easier to have a standardised TA of FL180 rather than having to fumble around with all of these different TAs for different countries or areas.
In a word, or two: terrain clearance.

Another word, or more: It makes it a lot harder on everyone to make the flight level stratum higher than necessary to account for terrain.
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Old 23rd Aug 2010, 09:16
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I am a liaison between our airline and ATC. Within Europe there have been discussions about harmonizing TA/TL. Alas these are, as usual, complicated by all the countries providing input. A big obstacle is the UK in this, as usual they are being particularly obstinate. There are currently two proposals circulating. One for FL180/TA18,000. The other being FL100/TA10,000. One of the prime drivers in this matter are the future CDO (continuous descent operations).

I have been told (jokingly) by one contact that in a typical European fashion we will probably end up with FL140/TA14,000. It is sad to see this subject taking this long.

The Rocky Mountains are comparable to the Alps, and FL180/TA18,000 feet works fine over there, would seem like a simple fit.

Last edited by Otterman; 23rd Aug 2010 at 09:32.
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Old 23rd Aug 2010, 12:05
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Surely if the TA is 18000 then the TL is FL190 or higher? Likewise with other transition altitude/level options? The gap between the TA and TL being the transition layer in which no man may cruise. Or is that peculiar to Australia and New Zealand?
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Old 23rd Aug 2010, 12:41
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AltFlaps, I believe Amsterdam stating the TA/TL on the ATIS is a byproduct of their low published TA of 3000'. I think they have to adjust actual TA any time the altimeter is below 1013 in order to maintain obstacle clearance. However, I stand to be enlightened by anyone with a better understanding.

Aerocat, you are correct. Transition layer is not particular to Aus/NZ, it just hasn't been discussed yet.

US airspace does not utilize the TA/TL nomenclature. If we did then TA would be 17000' and TL would be FL180 or FL190 depending on local altimeter.

Best,
GC
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Old 23rd Aug 2010, 12:58
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Roger. Out.
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Old 30th Aug 2010, 21:35
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If you fly around below FL180 you're probably doing it for fun and your aircraft is probably slow enough so you will not be exhausted by setting the local QNH once an hour.
Perhaps in the small European airspace...but a lot of folks make a living their entire life flying below 18,000.
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Old 30th Aug 2010, 22:23
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So its about time to untie it from the local terrain. If you fly around below FL180 you're probably doing it for fun and your aircraft is probably slow enough so you will not be exhausted by setting the local QNH once an hour. The volume of GA in Europe is microscopic compared to the US, how do you think they cope? However changing from STD to QNH in the middle of your approach after glide intercept, then go missed to a FL again is just plain stupid.
It has to be higher than the terrain. If you want a world wide TA/TL, you'll need it to clear the highest terrain in the world, FL180 wouldn't work for The Himalayas!

It sounds like what you really want is for the TAs in the regions that you fly in to be higher, that's not unreasonable, go lobby the government or something.
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