What do people think about this then?
 

I've been a bit surprised that no-one seems to be talking about the consultation that the CAA is running on the Transition Altitude being raised to 18K. What do people think?

If it happens in the next ten years, I'll be amazed.

Too many stakeholders who will see no benefit, and to whom it will be a massive expense and ballache. It will be squashed.

What is the reasoning behind the (possible) change ?

It's all for euroharmonization, except for those in europe who would like a different level. And the french of course, who will do what they want anyway. And yes, don't hold your breath!

I'm surprised that you're surprised. Its' been well covered outside Pprune.

I know that a lot has been done and that members of the project team have visited a lot of units to talk about specifics. I was just surprised that some of what has been proposed in the consultation materials hasn't stimulated more debate on the forum.

It IS a surprise that the CAA decided to consult on an 18,000ft TA. 18,000ft would not be easy to implement, however if the CAA direct it then 18,000ft it must be.

Is there any news of how the consultation is going? I've heard nothing since the consultation opened.

Let's get LAMP out of the way first, eh? :}

The London City Arrivals Management Program?

London Airspace Management Programme

https://www.caa.co.uk/Commercial-ind...amme-Phase-1A/

It's no longer a European Harmonisation effort though as HETA was dropped last year.

Resurrected from the dead http://www.pprune.org/atc-issues/476...-18-000ft.html

Dave - I think TMT was being ironic/sarcastic!

If the TA were raised to 18K or whatever what altimeter setting would everyone use beneath it?

QNH, fool, everyone cries!

Yeah, right. But which QNH? Regional? Near the border between 'em which regional? Local airfield? Local large airfield? Local LARS? Any one you please?

This might work in the vast empty spaces of the U S of A where for the most part there is only one city airport for hundreds of miles but in crowded UK you're going to end up with scores of en-route aircraft in close proximity all on different altimeter settings depending on who they are talking to or where they just came from, so how is that compatible with air safety? It works in the 3-4000ft predominantly VFR layer we currently have but I winder how it would work for mid level transit traffic on IFR flights.

There's no such thing as 'Regional QNH' any more.
I think the plan is to get rid of Regional Pressure Settings when the TA is raised. Aircraft inside controlled airspace will be given a QNH; aircraft outside should fly on the nearest reported QNH as they do nowadays when flying below a TMA.
I don't know what the RAF will do. I think their present procedures are to remain on QFE up to 3,000 ft then change to 1013. If remaining below 3,000 ft they use RPS when outside the MATZ.

See:

http://publicapps.caa.co.uk/docs/33/...7_TACONOPS.pdf

....page 10 in particular...

It seems sensible to replace the current confusing arrangement of different transition altitudes in the UK. 18,000 ft is used in the US because of terrain clearance. I suggest 6,000ft would be more appropriate to the UK. Having a TA at levels at or below which aircraft cruise could complicate matters. I guess 18,000ft is in the interests of the sacred cause of European harmonisation!

A transition Altitude of 6000' seems the best option to me, given that the highest obstacle in U.K. airspace is 4409'.
A TA of 18,000' is just below the level of many current area-sector interfaces. O.K., that could be changed, but as you can lose 2 flight-levels, it would require significant 'airspace engineering'.
Also in the U.K. we have quite deep low-pressure areas transiting the country, as recent events have demonstrated.
The steep pressure-gradients associated with these events cause significant rapid horizontal changes in QNH.
If you take an aircraft descending from FL200+ into the EGCC TMA, the QNH on passing the 18,000 TA (say, near EGNX), could easily be 4mb/hPa different from that required on final approach.
Also, The U.K. has a lot of traffic cruising around FL180/FL200. This would have a major impact on the availability of those levels.

In January 1995, I was involved in the EGCC evaluation of MIRSI/ROSUN and Runway 2 procedures at Bretigny-sur-orge. Before we set off, our ops manager gave me a paper to read concerning the planned withdrawal of Altimeter Setting Regions, and their replacement with local QNH.The main thrust of the argument for this was the requirement for a meteorologist to forecast RPS, and the associated cost. Fortunately, 21 years later, ASRs are alive and well, and said meteorologist still has a job.
Prior to that, there was CCF, another priceless failure from The Ministry Of Bright Ideas. :E

Good post, Zooker. l am in complete agreement.

Except that in the example that Zooker uses, the CONOP says that the 'area' QNH would, effectively, be the Manchester aerodrome QNH, so there wouldn't be a 4 hPa difference. The biggest difference is likely to be 2 hPa.