IMC outside CAS

[dont overfil]

Following on from the Glenforsa thread I am interested in others opinions about flying IMC outwith radar cover and outside controlled airspace.
I'm not sure if this is the correct forum for the following but here goes.

About 20 years ago a Loganair aircraft flew into high ground on an NDB approach to Islay. In the discussion that followed some of his fellow pilots admitted they preferred to descend on a radial from MAC as it was more direct and simpler.

I mentioned this just to highlight that the practice has occurred in the commercial world also.
Is radar available in the Scottish ADRs (Class F)?
DO

[TALLOWAY]

Radar is usually always available on the ADRs (subject to the usual limitations), but the ADRs base levels don't go down to the surface.

Radar wouldn't have helped the Loganair pilot as he was conducting a non precision approach with no radar service available. It's a recurring theme in Loganair fatalities, simply due to the nature of their operations and the airfields they were using at the times of the accidents.

The cumulo granite in Scotland is very unforgiving to people who make mistakes in IMC, as the number of crashes (many with bits of wreckage still present) will testify.

[englishal]

It must have been pilot error if they flew into a mountain on a *published* IAP.

A friend of mine did it though, with radar cover, and they all died. Controllers will obviously warn if they notice that there is a problem but often they are busy elsewhere and it is the pilot's responsibility. You'd be better off with GPS and a TAWS funtion, in that case I am 100% sure my friend and his passengers would be alive today (they messed up, meant to go Missed at the MAP in IMC but for some reason just carried on flying S&L straight into a mountain - had they been 15 feet higher they would have missed).

[Johnm]

I seem to have caused some interest at least:eek:

I fly quite a lot in IMC outside controlled airspace, as I only have an IMC and not an IR I can't fly airways so to get from A to B in poor weather there's not a lot of option.

Unsurprisingly I'll always take a radar service if I can get one and most units are helpful and sympathetic to those of us in this position. In particular in my neck of the woods Bournemouth Lyneham, Bristol and Brize have been unfailingly kind, helpful and professional.

[Squeegee Longtail]

Problem with IFR outside controlled airspace is that although you maybe on radar service, the other traffic may not be. I was once vectored away from unidentified traffic only to have the other contact start a series of course changes which always seemed to target me, no matter what heading I was given.
Slightly alarming - it was almost better not to know what was out there and play roulette with avoidance (which is what the IMC rating is).

[IO540]

Firstly, a radar service will be of NO help with hitting mountains, because the ATCO is not permitted to provide a service below a minimum vectoring altitude, and the MVA will generally be at, and often way above, the safety altitude for a wide area.

Secondly, there has not been a post WW2 midair in IMC in the UK. The sky is huge, and GA activity gets very thin the moment visibility falls below 100,000m and the cloudbase falls below 10,000ft :)

I did a nice VMC/VFR trip today, in ~ 4000m vis in typical English summer haze and there was almost no traffic about, presumably because one cannot navigate in these conditions using the goode olde PPL-style map compass and stopwatch method :) In IMC, the chance of hitting somebody else is utterly miniscule. It's away from Russian Roulette by many orders of magnitude.

And so many targets are non-transponding (the Civil Liberties crowd) that a radar service is worthless on perhaps 80% of conflicting traffic - because there is no altitude information.

[Squeegee Longtail]

"In IMC, the chance of hitting somebody else is utterly miniscule. It's away from Russian Roulette by many orders of magnitude."

Russian roulette maybe, but they are different odds to roulette as quoted!
Some airspace where I used to fly IMC is a "corridor" between Gatwick and London zones, and a vertically challenged one at that. The odds are high, granted, but it doesn't give you a warm fuzzy feeling hearing about other traffic in the "corridor" when in IMC, especially if there is no altitude info and they are not on a radar service.

[Shunter]

People who don't squawk charlie in IMC should be taken outside and shot. They really should...

You don't want a service? Fine. At least show some common sense and consideration towards those that do.

[Spitoon]

FWIW, as I recall the Loganair accident, the pilot had got visual contact with the surface (but not the runway) and was completing the approach visually. Sadly I believe there were two valleys ahead of him and for reasons that are not understood he went up the wrong valley - at least that seemed to be the consensus of those I knew in the company.

[Chilli Monster]

Firstly, a radar service will be of NO help with hitting mountains, because the ATCO is not permitted to provide a service below a minimum vectoring altitude, and the MVA will generally be at, and often way above, the safety altitude for a wide area

Not strictly correct.

Yes, you cannot vector below MSA, which is normally based on the 4 cardinal quadrants, each one being based upon its dominant obstruction in that quadrant within 25nm of the airfield. Outside of 25nm MSA normally becomes highest obstruction within 100nm of the airfield

MVA however will be established for vectoring to the final approach track, and will be an area within 10nm of the airfield where descent below MSA is possible.

A look at a Radar Vectoring chart for most airfields will show the difference.

[IO540]

The above may be in the UK but differs abroad, IME. I was well above the Alps under a radar service from Treviso, for example, and he told me I was below his MVA.

it doesn't give you a warm fuzzy feeling hearing about other traffic in the "corridor" when in IMC

What you actually find is that most of the said traffic is below the cloud. The typical scenario when flying in Class G, under an RIS, is that at least 90% of the "unknown level" contacts are kerb crawling way down below. There you are, sitting at say 3000ft, and you never spot most of them because they are nearly on the ground.

Granted, there is traffic at 2300/2400ft under the LTMA and one has to watch that. But the great majority of nontransponding traffic is very low - many being microlights, etc. These are virtually all non instrument capable pilots and they won't be in cloud.

The whole "PPL training culture" is to fly below 2000ft. I did all of my PPL training at 1500-2000ft and most PPLs rarely go above that. Now I fly as high as I can and find there is nothing much about.

People who don't squawk charlie in IMC should be taken outside and shot. They really should...

You don't want a service? Fine. At least show some common sense and consideration towards those that do.

Agreed, and I would apply it to VMC too :)

[TheOddOne]

The whole "PPL training culture" is to fly below 2000ft. I did all of my PPL training at 1500-2000ft and most PPLs rarely go above that.

Morning IO540,

That isn't the case for us. We routinely operate to & fro the training area (Aylesbury from Denham) at 2300, which is 200' below the TMA. This is the MSA for a part of the navigation routes we use & gets the student used to operating at this level. As soon as we get to Prestwood we climb to 3000' if the cloud allows for most of the early exercises, allowing climbing & descending, stalling etc. If the cloud is is <2000' then we confine ourselves to the circuit or cancel the detail, depending upon where the student has got to. I find it very hard to adquately teach climbing & descending, for example with much less than 2500', say 2000' AGL. Effects of controls & turning admittedly can be done at lower levels.

We teach students how to use the transponder along with the radio at an early stage and I use Farnborough LARS for the transit and when at the training area explain that we'll be operating various headings & levels. I call them again on the way back but emphasise to students that this doesn't replace the need to maintain a good lookout. I find covering up the instruments improves this latter!

TheOddOne

[dont overfil]

Yes, we are lucky in Scotland having no class A below 5500. Clearly the London and Daventry TMAs make life very difficult.
Once again the USA shows us how it should be done with very little class A under 18000. They do however have large areas where mode C is mandatory.
DO

[Rod1]

“The whole "PPL training culture" is to fly below 2000ft. I did all of my PPL training at 1500-2000ft and most PPLs rarely go above that.”

This is certainly not my experience, being midlands based. Perhaps it is true further south with the increase in CAS. I regularly see micros (3 axis) and gliders (both likely to be non radio or very short range radio and no Xpder) well above 2000 ft. I try to fly above 3000 ft + as it is a bit quieter, but this is probably because it takes some of the older kit a lot of time and fuel to get this high!

Rod1

[chevvron]

Chilli and IO540: the term Minimum Vectoring Altitude in not recognised in the UK and should not be used; it does not appear in MATS Part 1 and thus has no 'legal' definition, so where Chilli gets his defintion from I don't know.
There is no such thing as a Radar Vectoring chart; having been re-named 'Radar Minimum Altitude Chart' for a short time, the term used now is 'Surveillance Minimum Altitude Chart'.

[IO540]

Well you can all pick apart my sweeping turn of phrase :) but the fact is that most GA traffic does crawl low down, below 2000ft, and this is evident when flying under an RIS - most reported targets that one does spot (which is not a large %) turn out to be well below.

So anybody looking to minimise the chances of a contact should fly high.

And if one can get VMC on top, there is almost nothing there and one can fly for hours without a single GA contact. Much as is the case on airways flights especially outside the UK.

Instrument capable / instrument legal pilots don't sit in cloud. They use their privileges to remain VMC. Pilots who spend serious time in cloud will be mostly the UK IMC Rated pilots who are zooming around under the base of CAS and there aren't many of them around.

[dont overfil]

The thought of IMC with a radar service at 2500ft under the London TMA scares me more than johnm climbing into IMC up the wide expanse of the sound of Mull without one!
DO

[Rod1]

Well you can all pick apart my sweeping turn of phrase but the fact is that most GA traffic does crawl low down, below 2000ft, and this is evident when flying under an RIS - most reported targets that one does spot (which is not a large %) turn out to be well below.

So you are basing your opinion the targets which the radar can see. In my area 80% of the traffic would not have a Xponder and 50% no radio. I therefore suggest that using a RIS as a basis for anything in VMC is so flawed as to be a waste of time.

Rod1

[IO540]

yes................ hence fly high

[Johnm]

I agree with IO540 and I fky high and use quadrantals when in IMC in Class G 'cos that's what you are supposed to do and it's designed to arrange separation without radio aids at all.

I accept the issue with having to cope with narrow corridors in the Southeast but I also agree that it's usually a reasonably safe assumption that non transponding traffic is actually below the cloud base. I base this on considerable experience of having a RIS above the cloud and never seeing any reported non transponding traffic!