IFR outside controlled airspace
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From: 18nm NE grice 28ft up
IFR outside controlled airspace
I've just received the latest CAA notification update about possibly changing the transition level to 18000ft.
How will IFR outside controlled airspace <10000ft work if this proposal goes through?
D.O.
How will IFR outside controlled airspace <10000ft work if this proposal goes through?
D.O.
Thread Starter
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From: 18nm NE grice 28ft up
I did not put the question clearly. I was thinking of altimeter settings changing on route. I suppose the regional settings would do most of the time. As SK says it works fine in the USA. However am I right thinking there is no IFR outside controlled airspace in the rest of Europe?
It might be interesting to do the sums for near my home base where three altimeter setting regions come together. There are occasionally dramatic differences in settings between Portree, Tyne and Belfast.
D.O.
It might be interesting to do the sums for near my home base where three altimeter setting regions come together. There are occasionally dramatic differences in settings between Portree, Tyne and Belfast.
D.O.
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From: dk
How long before EASA puts an end to IFR outside controlled airspace?
Can you imagine this to be different between the member states. I don't think the other countries will accept this possibility in their air space
Can you imagine this to be different between the member states. I don't think the other countries will accept this possibility in their air space
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From: UK
I was thinking of altimeter settings changing on route. I suppose the regional settings would do most of the time. As SK says it works fine in the USA.
However am I right thinking there is no IFR outside controlled airspace in the rest of Europe?
Thread Starter
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From: 18nm NE grice 28ft up
Thanks Bookworm. That really does answer my questions and doubts. I hope you are right about IFR still being permitted in class G.
I see the ASRs will be rearranged and additional pressure reporting sites will be established. Lots of lovely new acronyms as well
D.O.
I see the ASRs will be rearranged and additional pressure reporting sites will be established. Lots of lovely new acronyms as well
D.O.
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From: a galaxy far, far,away...
I can't see any reason why IFR ATSOCAS would change much, if at all. Where I work, the TA has recently changed from 3000 to 6000'and has had negligible impact.
With reference to RPSs, don't forget that ASRs are huge, and a QNH from a nearby airfield will be a lot more accurate and may (currently) prevent banging your head on CAS above!
With reference to RPSs, don't forget that ASRs are huge, and a QNH from a nearby airfield will be a lot more accurate and may (currently) prevent banging your head on CAS above!
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From: UK
Quote:
However am I right thinking there is no IFR outside controlled airspace in the rest of Europe?
No, SERA permits it, and in fact some of the "rest of Europe" in which IFR is not currently permitted in class G is [hum=DambustersTheme]having to have a rethink[/hum].
However am I right thinking there is no IFR outside controlled airspace in the rest of Europe?
No, SERA permits it, and in fact some of the "rest of Europe" in which IFR is not currently permitted in class G is [hum=DambustersTheme]having to have a rethink[/hum].
Could be a requirement brewing for a simple to acheive, yet safe, qualification
that allows IMC(IFR) flight outside CAS.
I wonder what EASA could come up with? Probably nothing!
If only there was a current/historic Rating in a member state that might
fulfil, or form the basis, for this?
Avoid imitations
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From: Wandering the FIR and cyberspace often at highly unsociable times
I can't see any reason why IFR ATSOCAS would change much, if at all. Where I work, the TA has recently changed from 3000 to 6000'and has had negligible impact.
With reference to RPSs, don't forget that ASRs are huge, and a QNH from a nearby airfield will be a lot more accurate and may (currently) prevent banging your head on CAS above!
With reference to RPSs, don't forget that ASRs are huge, and a QNH from a nearby airfield will be a lot more accurate and may (currently) prevent banging your head on CAS above!
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From: UK
I totally agree! I fly from one ATIS to the next most appropriate one, rather than relying on the RPS which is, after all, a "best guess" forecast by a Met Man.
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From: UK
Surely the same as now if you are IFR under CAS defined as an altitude, i.e. 'the QNH of an airfield under the CAS' or words to that effect.
If you're receiving a service from ATC in the vicinity of an airport, it's easy -- you use whatever QNH they give you. The tricky case is where you're talking to no one in the middle of nowhere.
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From: in the classroom of life
IFR OCTA?
That is how MOST of it operates down here.
Heck even Airline ops are conducted IFR, OCTA in Class G and without radar or ADSB.
Do I think that AIrline ops should be....no, more like the USA with Radar and E, but we do it all day every day down here.
That is how MOST of it operates down here.
Heck even Airline ops are conducted IFR, OCTA in Class G and without radar or ADSB.
Do I think that AIrline ops should be....no, more like the USA with Radar and E, but we do it all day every day down here.
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From: Quite near 'An aerodrome somewhere in England'
The issue of harmonised TA is nothing like as simple as folk might imagine.
The real problem is the Transition Layer, which is of variable vertical extent and many cruising levels will be lost at and near the TA. Not a problem with a 3000 ft TA, because not much traffic cruises that low. With a 6000 ft TA, the Heathrow holds become a problem due to traffic separation standards and inbound IFR traffic on SPS approaching the vicinity. A 10000 ft TA would lose cruising levels popular with unpressurised IFR GA aircraft - and an 18000 ft TA would lose levels popular with airlines flying short legs (e.g. Birmingham to Dublin)..... One major airline has already said that 18000 ft would cause them financial issues.
Even if an 'ideal' TA is identified, traffic cruising below the TA needs to use an altimeter setting which meets a number of requirements. The ASRs would need to be large enough to avoid frequent changes of altimeter setting but not so large that a significant pressure gradient would cause unacceptable errors, the setting must meet MoD's terrain avoidance criteria, the same setting must be used both inside and outside CAS to ensure separation is maintained..... At aerodromes, there would need to be a point at which altimeter settings are changed to/from aerodrome QNH; even if on departure that was 'on completion of noise abatement or at the ATZ boundary, whichever later' that might conflict with inbound arrivals. And what about go-arounds?
It's a very complicated topic indeed; however, NATS are well aware of the issues which affect GA and will certainly involve us in any future consultation before a final decision is made.
And before Mr GPS pops up, no, you cannot simply rely on GPS altitude!
The real problem is the Transition Layer, which is of variable vertical extent and many cruising levels will be lost at and near the TA. Not a problem with a 3000 ft TA, because not much traffic cruises that low. With a 6000 ft TA, the Heathrow holds become a problem due to traffic separation standards and inbound IFR traffic on SPS approaching the vicinity. A 10000 ft TA would lose cruising levels popular with unpressurised IFR GA aircraft - and an 18000 ft TA would lose levels popular with airlines flying short legs (e.g. Birmingham to Dublin)..... One major airline has already said that 18000 ft would cause them financial issues.
Even if an 'ideal' TA is identified, traffic cruising below the TA needs to use an altimeter setting which meets a number of requirements. The ASRs would need to be large enough to avoid frequent changes of altimeter setting but not so large that a significant pressure gradient would cause unacceptable errors, the setting must meet MoD's terrain avoidance criteria, the same setting must be used both inside and outside CAS to ensure separation is maintained..... At aerodromes, there would need to be a point at which altimeter settings are changed to/from aerodrome QNH; even if on departure that was 'on completion of noise abatement or at the ATZ boundary, whichever later' that might conflict with inbound arrivals. And what about go-arounds?
It's a very complicated topic indeed; however, NATS are well aware of the issues which affect GA and will certainly involve us in any future consultation before a final decision is made.
And before Mr GPS pops up, no, you cannot simply rely on GPS altitude!
Last edited by BEagle; 10th May 2013 at 13:07.
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I know the USA is a totally insignificant part of the world's aviation scene, but before deriding this proposal as [various shades of] nearly impossible, has anybody asked how it works over there?
I recall being in a UK CAA presentation on GPS approaches, c. 2005, where the presenter (now a very high ranking figure in FCL) said that the CAA "found" that the FAA never analysed the reliability of GPS... So the CAA paid a bunch of consultants a load of £££ to do a GPS realibility study.
I recall being in a UK CAA presentation on GPS approaches, c. 2005, where the presenter (now a very high ranking figure in FCL) said that the CAA "found" that the FAA never analysed the reliability of GPS... So the CAA paid a bunch of consultants a load of £££ to do a GPS realibility study.