Practicalities of flying in IMC outside controlled airspace in UK

[BARThompson]

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!

[porterhouse]

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.

[Johnm]

I fly in IMC outside controlled airspace in the UK pretty often. I get a radar service almost invariably and fly quadrantals where practicable. It's not a problem.

[chevvron]

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.

[mad_jock]

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.

[Mach Jump]

''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

[thing]

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.

[Johnm]

I fly in IMC outside controlled airspace in the UK pretty often. I get a radar service almost invariably and fly quadrantals where practicable. It's not a problem.

[Cows getting bigger]

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".

[dirkdj]

Chevron,

VFR flight levels are semi-circular PLUS 500 in Europe.

[ShyTorque]

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.

[thing]

We do have the luxury of TCAS, which makes life a lot easier. Is this in a pro chopper or your own GA stuff? Does anyone rec a good coaming top TCAS?

[chevvron]

dirkdj:
So I understand, but the discussion I heard definitely said minus 500.
But there again, the CAA have not yet made a decision.

[abgd]

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.

The research base suggests that lookout is very limited as a means of preventing collisions and there are plausible guesstimates that we may see as little as 10% of potentially conflicting traffic when en-route. If that's the case then it would be fair to say that your IMC lookout is only slightly worse than your VMC lookout, and the main difference between the two is that you're far less likely to encounter traffic whilst flying in IMC.

Hangar Talk - Lookout - does it work? (http://www.euroga.org/forums/hangar-talk/457-lookout-does-it-work) for some discussion/links.

[Johnm]

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.

[ShyTorque]

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... :oh:

[chevvron]

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?

[ShyTorque]

I'm saving my failing laptop battery by writing smaller... ;)

[Curtis E Carr]

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.

Not quite.

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'.

Indeed.

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


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.


See COMMISSION IMPLEMENTING REGULATION (EU) No 923/2012 incl Part SERA (http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2012:281:0001:0066:EN:PDF). With particular regard to this issue, see SERA.5025 and Appendix 3. In line with the Regulation, the CAA has proposed the following amendment to Rule 34:

(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:

(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.

I believe that for the UK, the transition to Part SERA is to take effect from 4 Dec 2014.

Finally, this paper (http://www.caa.co.uk/docs/2408/20120330ClassGConOpsVr1doc.pdf) by the CAA may be worth a read.

[funfly]

I fly in IMC outside controlled airspace in the UK pretty often. I get a radar service almost invariably and fly quadrantals where practicable.

Am I not correct in thinking that it is obligatory to fly flight levels in IMC, not just where practical?

FF

[Curtis E Carr]

Not always obligatory. See third quote above.

[phiggsbroadband]

For lots of GA aircraft, the concept of a Semi-Circular Cruising Level is all a bit academic.
Take for example a Slingsby T67M flying from North Wales to South Wales, who wants to reach 8000ft to cruise. At 400ft/min this climb will take him 20 minutes. So 2/3 of the 90 nm trip will comprise climbing or descending with just 1/3 (20 minutes) at the semi-circular cruising level.
By the time you add in all the dodging under or over controlled airspace, not much of the trip will be in level flight.

[piperarcher]

Yes, this the dilemna of having an IMCr. No guaranteed radar service unlike our more privileged friends with a full IR. On a bad weather day you are more likely to get a traffic service than a 'basic service due controller workload'. Its the risk you take to be honest.

I occasionally fly in IMC according to IFR rules without a traffic service, but being in the South East of the UK, there is slim chance that Farnborough will give you a warning of a potential collision - though absolutely no guarantees. If I do fly in IMC, it is to get through some cloud and fly on top in clear air. I wouldnt do prolonged flight in cloud without a traffic service, and I'd avoid gliding sites. It is a case of risk management and weighing up the odds.

[Curtis E Carr]

Yes, this the dilemna of having an IMCr. No guaranteed radar service unlike our more privileged friends with a full IR.

Are you suggesting that if one is the holder of an IR, one is guaranteed to receive a radar service?

[piperarcher]

Are you suggesting that if one is the holder of an IR, one is guaranteed to receive a radar service?

OK, I cant guaranteee anything, slightly poor phrase. But OCAS, but with an IR (assumming aircraft capabilities and no icing issue), you can file a flight plan, get clearance (not always quickly I accept) to enter CAS, and there, you are more likely to be able to get a traffic service for the majority of your journey. In the UK, I am talking 'London Control'.

With an IMCr, sure you might sometimes be approved to enter some CAS with restrictions, but invariably you will still be in class G, and its hit and miss if a) any of the LARS military zones are open and able to give you a service b) in the South, Farnborough LARS has at least one controller for each of the 3 zones (sometimes there is one person covering two zones), and isnt maxxed out with lots of other GA traffic and only capable of giving you a basic service.

[Johnm]

If you file IFR and route in controlled airspace you aren't getting a traffic service you are getting a radar control service.

[ShyTorque]

PA, most corporate helicopters are obliged to operate outside CAS in the way that you perhaps believe to be second best and therefore "reserved" for IMCR only rated pilots. Departing from and arriving at private helicopter landing sites, it's the only practical way it can be done. It's not necessary to file a flight plan, we just get on with it.

[thing]

If you file IFR and route in controlled airspace you aren't getting a traffic service you are getting a radar control service.

You get a radar service no matter what service you are on, hence 'G-**** you are now under radar control' when you enter CAS. It differs on what they are obliged to tell you but it's still radar control and thou does as thou is toldeth.

[xtophe80]

It is only 130.4 MHz for glider cloud flying

[Pace]

Don't forget that it is not just light aircraft that operate out of CAS IFR with no radar coverage. Even a 737 flying into an airport like EGAE (Londonderry once leaving the BEL VOR is out of CAS out of radar coverage and positioning for a procedural approach and landing.

I used to fly into Londonderry in a twin and on a number of occasions was told to take up the hold to await my turn at the procedure. Once I had a 737 holding above and another aircraft below all relying on each other to be where we say we are and no real confirmation other than TCAS readouts

Pace

[Romeo Tango]

I am perfectly happy to fly IMC/IFR outside controlled airspace, usually without a service but squawking 7000. It is a VERY good risk.

[Pace]

There are obviously risks even if small! I posted sometime ago about a near miss with a Glider flying in cloud. I was descending from 10K well south of a known glider sight and was close enough to see the glider flash past in cloud.

That was the only very near miss I had in IMC in 30 years of flying.
I have also had two near misses in VMC VFR so I do not expect the risks are any higher.

There are precautions you can take. Fly High especially above cloud if possible or High in cloud as the chances of anyone being in your airspace are less.
invest in TCAS as it will at least alert you to other transponding aircraft.

Beware breaking cloud as often just under the cloud base is where you will find a lot of aircraft and gliders.
Bad weather days are usually days where only the have to fly guys will be up so chances of hitting one are small.

Communicate!!!!!!! vitally important to be on the correct frequency and listening out for other traffic at or around your level If you hear such an aircraft communicate a position and level report etc.

i have flown top to bottom in Africa and even airways communication is vital with position reports and estimates forget radar in those areas you often do not even have radio contact having to relay to airlines above.

So flying IFR OCAS in IMC probably has no greater collision risk than flying VFR in VMC Just reduce that risk by taking a few precautions

Pace

[piperarcher]

Do glider pilots flying in clouds have an IMCr or some other qualification that allows them to fly without sight of the surface?

[ShyTorque]

They have "another qualification" and fly with it strapped it to their backs. :E

[Pace]

We all have a right to the Sky and there have been long discussions previously on this.

Think they are treated as a special case by the authorities as no they do not have instrument flying qualifications and it would be almost impossible for them to fly to IFR rules because of inability to maintain altitude (usually)

It would be better if they had a transponder but few do for various reasons!
But yes you will find gliders in cloud as well as circling around the bases.

I always thought it was double standards to allow non instrument qualified pilots to fly non instrument equipped and non IFR capable aircraft in IMC while declining IMCR rated pilots with highly equipped homebuilts the same privileges which they are allowed to do in the USA.

But hey thats life :E loads of things are not fair

Pace

[piperarcher]

I always thought it was double standards to allow non instrument qualified pilots to fly non instrument equipped and non IFR capable aircraft in IMC

My thoughts exactly. Regardless of statistics it would 'feel' safer flying in IMC OCAS, if the only other aircraft in there were IMCr/IR qualified pilots, with appropriately categorised aircraft, and ALL had their transponders on. We all have a right to the sky, but when it comes to a potentially dangerous area of the sky like a cloud, the only people really with rights should be those qualified and transponding. Where one cant get a radar service, or one doesnt have an expensive TCAS (I'm talking the proper ones at £10k), it would be a bit safer if clouds didnt potentially contain gliders. Nothing against gliders as such, but its sort of one law for one, another law for another, and its unsafe, especially if they are not transponding or only using FLARM to see each other.

It's like mandating that car lights have to be switched in dark and low visibility conditions, but allowing motorbikes or some other vehicle randomly free access to go up and down the motorway whichever way they like, with their lights off, donnned completely in dark attire.

[Pace]

But then I don't think there have been IMC collisions with gliders and powered aircraft so on the whole the big sky theory must work?
My experience must have been one of the closest calls :E
Nevertheless there have been good VMC collisions between gliders and powered aircraft one even in CAS where gliders are also allowed to go (still? )

Pace

[Jim59]

Do glider pilots flying in clouds have an IMCr or some other qualification that allows them to fly without sight of the surface? Under current UK regulations they do not have to. In practice probably the majority of sailplane pilots that fly in cloud hold, or have held, an aeroplane instrument qualification.

The derogation from European rules ends 7th April 2015. Before then new rules will be in force providing for the EIR (En-route Instrument Rating) for power pilots and SCFR (Sailplane Cloud Flying Rating) for sailplane pilots.

Once the new rules are in place then sailplane pilots will require the SCFR to fly in cloud. There is a theoretical and flight training syllabus to be completed at an ATO followed by a skills test with an EASA examiner.

[soaringhigh650]

Airprox 2013071 (http://www.airproxboard.org.uk/docs/423/20131127-2013.11Reports.pdf) highlights the importance of obtaining a Deconfliction Service in IMC.

[mad_jock]

The airprox board are in cloud cuckoo land if they think GA is going to get a deconfliction service. Which is why most don't bother to ask for it.