Transition Altitude

[wrecker]

I see the UK CAA is consulting on a raising of the Transition Altitude to 18000ft.

[peterh337]

Excellent :ok:

[mad_jock]

How do they sort out QNH's along airways below that in the US peter?

[mad_jock]

So do you just pick the nearest field and use that?

I am not having a go at the way the US do it just trying to figure out how it would work in the UK going North South at FL160 and a 30mb gradient as per hurrican bawbag gave us. Maybe use the regional QNH's?

[achimha]

Why would this be excellent Peter? I've always considered FLs to be rather convenient.

[UL730]

More information: Consultation on the Policy to Introduce a Harmonised Transition Altitude of 18 000 ft in the London and Scottish Flight Information Regions.

http://www.caa.co.uk/docs/2257/20120131HarmonisedTAConsultationDocument.pdf

I would have presumed that we would have maintained quadrantal levels up to 18,000 but there is a suggestion of implementation of a new semi circular altitude based cruising level system outside CAS.

[NorthSouth]

Yes, we'll be moving to the ICAO standard semi-circular rule. The proposal is that Regional Pressure Setting will be the main basis for altimeter settings away from airports, with a revision of the Altimeter Setting Region boundaries.
NS

[mm_flynn]

So do you just pick the nearest field and use that?

I am not having a go at the way the US do it just trying to figure out how it would work in the UK going North South at FL160 and a 30mb gradient as per hurrican bawbag gave us. Maybe use the regional QNH's?

it would be quite unusual (other than right near the hurricane) to have more than about 1mb per 15 miles. So you wind up picking up weather info as you pass airports, from flight following, from a FSS, etc. If you are going to fly a couple of hundred miles into a low with no weather stations, first, there will be no CAS around (otherwise you would have a weather station) and second, you need to heed the PPL advice in the AIM of 'high to low lookout below' and be extra cautious on terrain separation altitudes (but you are VFR after all so can see the terrain or the top of the cloud).

[mad_jock]

Mate I don't have a problem with a transition at 18000. It operates in quite a few other places in the world quite fine with me.


In fact it will save all the ball ache of SID's with potential for alt busts due to changing to FL level offs.

The issue really isn't with VFR its the amount of IFR which bangs around lower than 18000ft in the UK. Alot of approaches cross departures from other airports and even FIR's.

In the UK we have CAS class A airways down to FL80.

[ShyTorque]

IFR in the US is flown in controlled airspace. Otherwise, we generally get the altimeter setting from ATIS or ASOS radio frequencies, one of which is available almost anywhere. The differrence is that ATIS is recorded hourly by a human, ASOS is entirely automated and continuous. Neither involves talking to a controller although controllers can and will provide the altimeter setting too.

I fly IFR a lot of the time OCAS (in UK) and I use the ATISes from the nearest airfield in exactly the same way, or obtain the local QNH setting from a controller. As well as being more accurate, observing the changes in en-route QNH sometimes helps give an indication of the passage through a weather front.

Regional Pressure Settings? Using RPS under controlled airspace has resulted in a number of airspace busts, many of them by aircraft climbing out from low level. It's a system designed aeons ago, to help keep pilots above terrain when out of ATC contact for long periods.

Bearing in mind that by nature the RPS is a forecast for a large area and may be quite inaccurate (and pessimistic), I now use it only if I can't get a relevant QNH to use instead.

UK ATISes are updated more often than hourly, depending on the changing weather.

[peterh337]

I don't see any downside to this at all.

Currently we have a bizzare mixture of CAS bases in altitude and flight level. In some cases you have e.g. 5500ft and FL055 next to each other. Anybody looking to reduce CAS busts will tear their hair out right there.

There is no pilot-procedural downside because low airways IFR traffic (below 18k) will almost always be in CAS and then ATC pass you the QNH along with the altitude to fly. You don't dial up anybody's ATIS to get the QNH. It is only OCAS that the pilot will need to get the QNH and that is what he does at present anyway (or should do).

The alignment with US practice is a bonus. A lot of foreign pilots trained in the USA and they find Europe's airspace, with the Eurocontrol computer with its perverse rules, totally baffling, and the 18k transition will reduce the baffle factor a little bit :)

Pulling the plug on the whole of Eurocontrol would be the icing on the cake - I have just finally managed to file an IFR route for tomorrow (with DCT hacks) which defeated all the software tools, including Eurocontrol's own "route suggest" facility :ugh:

[soaringhigh650]

I have just finally managed to file an IFR route for tomorrow (with DCT hacks) which defeated all the software tools, including Eurocontrol's own "route suggest" facility

:uhoh: Why do you need to hack computers to go flying?

[172driver]

Does anyone know if this is a Europe-wide initiative ? The consultation doc (which I have only skimmed) mentions Europe several times but then goes on to say something to the effect that initially there will be a difference in the TA between the UK and adjoining FIRs (which, at present, have TAs lower than 18000 ft).