Practicalities of flying in IMC outside controlled airspace in UK
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Practicalities of flying in IMC outside controlled airspace in UK
Perhaps a stupid question, but...
...As far as I can see, it doesnt seem be a requirement under the instrument flight rules for a pilot to be in receipt of a radar service when flying in IMC outside of controlled airspace. I know the quadrantal rules will provide some separation, but there must be 'pinch-points' in UK airspace that mean this isn't sufficient protection??
As such, is it not a frequent event that an appropriately licensed pilot approaches the boundary of the cloud, seeks a deconfliction service (say) but is only offered a basic service due to workload. So his decision is to turn around (which seems a share seeing he has the ability to continue) or plough on anyway (legally, as I understand it) but without a controller watching over him - essentially just hoping he doesnt hit another pilot also crossing his fingers?
Perhaps an IR or IMC pilot could explain to me the differences in the legalities and the practicalities of flying in IMC outside controlled airspace. I may simply have my facts all mixed up!
...As far as I can see, it doesnt seem be a requirement under the instrument flight rules for a pilot to be in receipt of a radar service when flying in IMC outside of controlled airspace. I know the quadrantal rules will provide some separation, but there must be 'pinch-points' in UK airspace that mean this isn't sufficient protection??
As such, is it not a frequent event that an appropriately licensed pilot approaches the boundary of the cloud, seeks a deconfliction service (say) but is only offered a basic service due to workload. So his decision is to turn around (which seems a share seeing he has the ability to continue) or plough on anyway (legally, as I understand it) but without a controller watching over him - essentially just hoping he doesnt hit another pilot also crossing his fingers?
Perhaps an IR or IMC pilot could explain to me the differences in the legalities and the practicalities of flying in IMC outside controlled airspace. I may simply have my facts all mixed up!
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I have no clue how you do it in UK but can tell you how we do it in the US and how FAA looks at it because it is based on some common sense rules, nothing else.
Flying IFR in uncontrolled airspace is not specifically forbidden but you are on your own - no radar services, nothing. There is only one case when such flying makes any sense - you are sitting in some remote uncontrolled airport, got IFR clearance on the ground and somehow you must takeoff and climb (say in IMC) high enough to finally reach controlled airspace to be seen by the radar, this scenario can be specially amplified in mountainous terrain. Chance that someone else will be in this cylinder of airspace right above the airport is infinitesimal small (presumably you are on radio frequency for this airport) so this sort of flying does make sense. But I can't phantom any other scenario in which flying in IMC in uncontrolled airspace would make any sense.
Flying IFR in uncontrolled airspace is not specifically forbidden but you are on your own - no radar services, nothing. There is only one case when such flying makes any sense - you are sitting in some remote uncontrolled airport, got IFR clearance on the ground and somehow you must takeoff and climb (say in IMC) high enough to finally reach controlled airspace to be seen by the radar, this scenario can be specially amplified in mountainous terrain. Chance that someone else will be in this cylinder of airspace right above the airport is infinitesimal small (presumably you are on radio frequency for this airport) so this sort of flying does make sense. But I can't phantom any other scenario in which flying in IMC in uncontrolled airspace would make any sense.
Don't know the timescale but in the near future, the UK will switch to the 'semi-circular' rule for IFR flight outside controlled airspace in order to bring us into line with the rest of Europe. I believe the plan is for VFR traffic to be recommended to fly at semi-circular minus 500ft.
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Safest place to be is IMC in class G to be honest.
Above FL100 and in IMC even safer.
Hasn't been a mid air in IMC for 50 odd years.
http://www.airproxboard.org.uk/docs/423/BOOK%2028.pdf
There has been a reduction in airprox's involving traffic with no service and a huge increase in the number while under a traffic service.
Above FL100 and in IMC even safer.
Hasn't been a mid air in IMC for 50 odd years.
http://www.airproxboard.org.uk/docs/423/BOOK%2028.pdf
There has been a reduction in airprox's involving traffic with no service and a huge increase in the number while under a traffic service.
''Perhaps a stupid question, but...''
First, there are no stupid questions!
The situation in the UK is that if you are flying in IMC outside CAS you must fly under IFR, which essentially means you must maintain at least 1,000' above the highest fixed obstacle within 5 miles of the aircraft, and follow the quadrantal/semicircular rule. You are not required to obtain any form of radar service.
Having said that, most smart people try to get at least a traffic service from a nearby LARS before entering cloud. There are times though, when no radar service is available, and then it's up to the judgement of the individual whether he should continue or not.
MJ
First, there are no stupid questions!
The situation in the UK is that if you are flying in IMC outside CAS you must fly under IFR, which essentially means you must maintain at least 1,000' above the highest fixed obstacle within 5 miles of the aircraft, and follow the quadrantal/semicircular rule. You are not required to obtain any form of radar service.
Having said that, most smart people try to get at least a traffic service from a nearby LARS before entering cloud. There are times though, when no radar service is available, and then it's up to the judgement of the individual whether he should continue or not.
MJ
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As MJ says the chances of hitting something else in a cloud are incredibly low. If you did then it was probably one of those days that you would have been licked to death by a goat if you hadn't been flying.
That's not to say you shouldn't take all and any safety precautions obviously. Get a deconfliction if you can, fly at the correct levels etc. Keep a good lookout...
( that last bit was a joke, just in case...)
I don't have any issues flying IMC in class G, quite happy to do so.
Edit: One thing to be aware of is that on a good thermic day (can you recognise one?) there's a chance that gliders may be either in or around cloudbase. Something to be aware of when descending out of the muck. In fact I'll narrow that down, something to be aware of when descending out of Cu. Best just to pop out the side and let down around the clouds.
That's not to say you shouldn't take all and any safety precautions obviously. Get a deconfliction if you can, fly at the correct levels etc. Keep a good lookout...
( that last bit was a joke, just in case...)I don't have any issues flying IMC in class G, quite happy to do so.
Edit: One thing to be aware of is that on a good thermic day (can you recognise one?) there's a chance that gliders may be either in or around cloudbase. Something to be aware of when descending out of the muck. In fact I'll narrow that down, something to be aware of when descending out of Cu. Best just to pop out the side and let down around the clouds.
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I always find the "there hasn't been a mid-air in IMC....." argument to be a bit tenuous. I prefer to consider how many mid-airs there have been in Class G and then try to ascertain the overall risk. It is fair to say that mid-airs in VMC have largely occurred due to failure of lookout - one could assume that being stuck in a cloud is the equivalent of failing to lookout, to a far greater degree. Consequently the counter-variable has to be related to the reduced number of pilots floating around in IMC compared to those operating in VMC.
So, if you subscribe to the big sky small number theory, crack on. Alternatively, mitigate with a radar service or steer clear of cloud.
As Dirty Harry would say, "Do you feel lucky, punk?"
PS. How many 'airprox' have there been where pilots don't even know it has happened? Donald Rumsfeld would describe this as the "unknown, unknowns".
So, if you subscribe to the big sky small number theory, crack on. Alternatively, mitigate with a radar service or steer clear of cloud.
As Dirty Harry would say, "Do you feel lucky, punk?"
PS. How many 'airprox' have there been where pilots don't even know it has happened? Donald Rumsfeld would describe this as the "unknown, unknowns".
Last edited by Cows getting bigger; 11th Feb 2014 at 20:19.
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It can be impossible to fly semi-circular rule or Quadrantal rule in much of the Midlands and the south of England due to CAS beginning below 3000'.
I've never asked for a Deconfliction service and probably never will because I've seen that it's almost impossible to achieve once unknown traffic comes into the equation, which it usually does. Having listened to others having asked (and being totally screwed around on some occasions, an own goal) it quickly becomes obvious that it increase ATC's workload enormously, in that they are obliged to attempt to deconflict everyone but cannot. A "pop-up traffic" or two and you're in for a zig zag track at best.
Far better to ask for a Traffic service and make your own arrangements regarding avoidance. We do have the luxury of TCAS, which makes life a lot easier.
At known choke points, I sometimes prefer to request an IFR crossing of CAS, to gain some better protection from unknowns.
I've never asked for a Deconfliction service and probably never will because I've seen that it's almost impossible to achieve once unknown traffic comes into the equation, which it usually does. Having listened to others having asked (and being totally screwed around on some occasions, an own goal) it quickly becomes obvious that it increase ATC's workload enormously, in that they are obliged to attempt to deconflict everyone but cannot. A "pop-up traffic" or two and you're in for a zig zag track at best.
Far better to ask for a Traffic service and make your own arrangements regarding avoidance. We do have the luxury of TCAS, which makes life a lot easier.
At known choke points, I sometimes prefer to request an IFR crossing of CAS, to gain some better protection from unknowns.
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We do have the luxury of TCAS, which makes life a lot easier.
It is fair to say that mid-airs in VMC have largely occurred due to failure of lookout - one could assume that being stuck in a cloud is the equivalent of failing to lookout, to a far greater degree.
Hangar Talk - Lookout - does it work? for some discussion/links.
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I agree, with the point about traffic service versus de-confliction service. A de-confliction service just gets you vectored all over the sky. A traffic service will usually tell you about transponding traffic and, apart from gliders, non-transponding traffic is unlikely to be flying in IMC.
It's gliders in clouds that make me nervous and I'll try to get above where they are likely to be wherever possible and/or give their sites a wide berth.
It's gliders in clouds that make me nervous and I'll try to get above where they are likely to be wherever possible and/or give their sites a wide berth.
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Now..... you've done it! Stand by for "incoming" from some of the gliding community... who will tell you that gliders are likely to be anywhere in cloud, that you must fit FLARM, listen on their frequency (rather than to an appropriate ATC unit, although they won't tell you they are there because they don't have RT licences) etc etc... 
Always provided you know which frequency of the group of BGA assigned frequencies (129.9, 129.975, 130.1, 130.125, 130.4 and possibly more) they are using!
and why are you whispering?
and why are you whispering?
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I'm saving my failing laptop battery by writing smaller... 
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The situation in the UK is that if you are flying in IMC outside CAS you must fly under IFR, which essentially means you must maintain at least 1,000' above the highest fixed obstacle within 5 miles of the aircraft, and follow the quadrantal/semicircular rule.
It can be impossible to fly semi-circular rule or Quadrantal rule in much of the Midlands and the south of England due to CAS beginning below 3000'.
From the Rules of the Air Regulations 2007:
34.—(1) Subject to paragraphs (2) and (3), an aircraft in level flight above 3,000 feet above mean sea level or above the appropriate transition altitude, whichever is the higher, shall be flown at a level appropriate to its magnetic track, in accordance with Table 1 or Table 2, as appropriate.
etc
etc
Don't know the timescale but in the near future, the UK will switch to the 'semi-circular' rule for IFR flight outside controlled airspace in order to bring us into line with the rest of Europe. I believe the plan is for VFR traffic to be recommended to fly at semi-circular minus 500ft.
(1) An aircraft in level flight outside controlled airspace at or below 3,000 feet above mean sea level and operated in accordance with the instrument flight rules is not required to be flown at a cruising level appropriate to its magnetic track.
(2) An aircraft in level flight outside controlled airspace and operated in accordance with the instrument flight rules is not required to be flown at a cruising level appropriate to its magnetic track if it flies:
(2) An aircraft in level flight outside controlled airspace and operated in accordance with the instrument flight rules is not required to be flown at a cruising level appropriate to its magnetic track if it flies:
(a) in conformity with instructions given by an air traffic control unit;
(b) in accordance with holding procedures notified in relation to an aerodrome.
(3) Aircraft in level flight and operated in accordance with the visual flight rules at any level are not required to be flown at a cruising level appropriate to its magnetic track unless flying in conformity with the conditions prescribed by the appropriate air traffic control unit.
(b) in accordance with holding procedures notified in relation to an aerodrome.
Finally, this paper by the CAA may be worth a read.
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I fly in IMC outside controlled airspace in the UK pretty often. I get a radar service almost invariably and fly quadrantals where practicable.
FF