IFR or VFR?

[Woss goin on..?]

Setting the scene:

3500 -RA SCT004 BKN006 OVC008

You want to depart in a fixed wing from an airfield with the above weather. You elect to depart VFR and immediately enter IMC on departure, climb to your desired altitude which is a common altitude flown in this congested airspace of the UK where further climb is limited by the TMA. As you have departed VFR, you are receiving no form of radar service even though good coverage and service is provided by two separate radar units located nearby.

Questions posed:

1: Is this departure legal under the VFR rules and do you consider these rules are clear, and understood fully by pilots or are they unduly confusing?

2: If it is considered legal, do you consider it sensible to depart in these conditions, fly IMC with no form of radar cover, and no way of avoiding other aircraft which may be in your path?

3: If the rules are understood and it is not considered sensible, what reasons would a pilot choose for not departing IFR? Is there a worry about route charges or something similar?

Discuss!


(edited for typos)

[Evo]

OK...

1 - if you're under 140kts then with 3k+ visibility I think it is legal. I guess the "I think" means that yes, the rules can be confusing, but the they are probably fine in most conditions - I think the confusion is for conditions far below what most PPLs or PPL/IMCs would fly in.

2 - Departure in these conditions is reasonable with an IR, bit daft with just an IMC (cloud conditions are well below the recommended minima for an IMC holder). I'm assuming that there's no icing or the aeroplane can cope with it. En route, well there's not going to be very much in the way of traffic flying in uncontrolled airspace in that weather and it's a big sky. I'd guess that the chances of a mid-air are much lower than other failures that could spoil your day (although I have no data to substantiate that).

3 - Dunno, ISTR that route charges could be involved.

[FlyingForFun]

1) I think it's legal to take off, but I'm not certain... but only if there are sufficient gaps in the "SCT004" layer for you to get high enough to satisfy the 500' rule. It is not legal to enter the clouds.

2) If you're departing VFR, then it's not legal to do what you're suggesting, because you're not allowed to enter cloud. If you're departing IFR, then it is legal. As for sensible, that would depend how busy the airspace was, and whether it is in controlled airspace. If it's in controlled airspace (even non-radar) then ATC will provide me with at least some separation. (Assuming Class D, they will separate me from other IFR aircraft only), so I see no problem with it.

If it's uncontrolled, then you have two choices. Option 1 is what you are describing, except that you would be IFR, not VFR. I would suggest that this is only safe in very quiet airspace. Option 2 is to depart VFR, level off below the clouds, and stay there until you get a radar service. Since not many private pilots fly in this type of weather, LARS stations are generally quiet so getting a radar service, assuming you're in area that's covered, won't be a problem.

3) Can't think of any reason for departing VFR in these conditions, unless, as I described above, you're planning on levelling off before getting radar service (which you can't do under IFR in these conditions because of the 1000' rule).

I think, though, that most of these problems answer themselves once you understand the difference between VFR and IFR in UK Class G airspace. Basically, you can switch between the two at will. There is no requirement to tell anyone which set of rules you are flying under at any given time. There is no requirement to be talking to anyone if you're IFR outside of controlled airspace. The only significant differences (apart from the obvious about flying in clouds and out of sight of the surface) are the 1000' rule and the requirement to fly at quadrantal levels if above 3000' when under IFR.

FFF
--------------

[IO540]

Can one do an IFR departure from a small airfield with no ATC and no IAP? I don't think so, and this is why one would depart VFR.

Assuming an IMCR or IR pilot and an aircraft suitably equipped for flight in real IMC (i.e. not your typical self fly hire spamcan) there is nothing illegal about the scenario described, departing VFR and changing to IFR right away and asking for an RIS.

At say 500ft agl you will need to be very close to the radar unit to get RIS because they need both primary and secondary returns. In fact I recall something about radar units not providing a RIS below 1000ft or something like that.

I would ask the tower to call the radar unit so you takeoff with the squawk already set.

The only real danger (unless one gets into the "IMC without RIS flight is dangerous" argument, for which there is no supporting data) is that on engine failure one would have about 10 seconds to find a suitable field...

I have taken off in OVC003 but that was immediately over water, so no need to look for a field :O Then climbed to FL070 and still in IMC... but icing wasn't a problem there.

[FlyingForFun]

Can one do an IFR departure from a small airfield with no ATC and no IAP? I don't think soI disagree - I'm not aware of anything that would prevent you from doing this. In fact, you have to do it every time you leave a small airfield with no ATC at night.

FFF
----------

[Flyin'Dutch']

Under these conditions you can not depart VFR.

That is pretty clear from the regulations.

You can only fly in IFR outside CAS but there is no reason why you should not ask for a service from a nearby unit as soon as you find yourself in IMC.

If there is no unit around that can give you a service and you feel uncomfortable you would probably benefit from a revision of your decision making processes before your next flight as it means that you have taken off in rather cruddy weather from an airfield without an IAP.

Some would say that is not the cleverest thing to do if you are in a twin, most would say it was unclever in a single.

FD

[FlyingForFun]

Under these conditions you can not depart VFR.Do you have any references for this? My understanding is that, as long as the gaps in the clouds are sufficient for you to get 500' from buildings, structures, vehicles, etc etc, there is no legal reason not to depart VFR (whether it's wise or not is a different matter). But I'm not certain of this, and if you can find anything to the contrary I'd be interested to read it.

FFF
-----------

[Keef]

I faced almost exactly this situation yesterday, except that I would have called it an IFR departure. There was also an IAP (or several) at the departure field.

I didn't go, because I was worried about being above the freezing level and in cloud. Had the freezing level been higher (as it turned out it was, later on), I'd have gone. Legally, I'm sure.

It's probably in the UK AIM, but there's no index to that, and I rarely succeed in finding what I'm looking for in it (short of reading the whole pesky thing each time).

I've flown a lot of "IMC Rating IFR" in the UK, and ask for a RIS whenever I can get one. It's extremely rare for there to be anything else around in those circumstances, so the "big sky" theory protects me.

I also avoid routing over VORs (honeypots) or at round multiples of 500 feet, or at 2400 feet round the LTMA.

Not departing IFR? The only reason would be if you were in something over the magic weight limit, at which point you'd incur hefty Eurocontrol charges. So you depart VFR and avoid the charges, then change to IFR when airborne.

[alphaalpha]

Keef -- I'm not sure you're right about avoiding IFR charges by making a VFR departure (assuming your aircraft is heavy enough to incur IFR charges). My understanding is that IFR charges are incurrred if ANY part of the flight is IFR.

Of course, if nobody knows you're IFR, then you won't be charged.

But the whole point is that you go IFR either because your weather is worse than the VFR minima or because you chose it for safety/convenience. In either case you chose so should be prepared to pay (without opening the avgas duty etc cans of worms or the 'but I got no service' argument ;-)) ).

AA.

[englishal]

Just to recap (for myself:D)......UK VFR minima in class G (assuming class G) specify minimums of 1500m vis, clear of cloud and in sight of surface below 3000' and 140Kts. Above 3000' its 5km vis, 1500m from cloud and 1000' vertical seperation from cloud....

So i suppose in theory you could depart VFR and remain "clear of cloud and in sight of the surface" and not break the 500 or 1500' rule.

As mentioned, switching between VFR and IFR outside CAS in the UK is a sinch, you just do it. Depending on why I wanted to fly would determing whether I depart IFR VFR or at all. If travelling A to B, I would file an IFR flight plan (icing permitting) and depart IFR. If I was just going for a jolly, I wouldn't go, as "Max VFR" (named after a friend of mine, who specialized in dodgey VFR :D) is highly dangerous in my book.

Departing IFR, and filing an IFR flight plan would probably help in getting a RAS, though I am not sure on how the system works with regards to routing IFR flight plans. Probably a LARS unit wouldn't get a copy. Every time I've pre-filed though, it certainly seems easier to get a RAS. Also pre-filing seems to help getting airspace transitions, and you won't get a routing change unless you are inside CAS and they want to change your route for some reason. ATC cannot route you through un CAS, and to enter CAS you'd have to have an IR and fly the airways. When transitioning Class D airspace, you'll be provided Radar Control service, where you're essentially given vectors to fly, so no big deal there.

Probably the worst thing you could do in this situation is depart VFR, then switch to IFR once airborne especially if you then want to negotiate CAS transitions. At least when you pre-file, someone knows you're going to be there.....

Cheers
EA

PS Depating a field with no IAP is no problem. Just remember you may not get back in again in an emergency, so it could be considered un wise unless you have an alternate nearby, or have made up your own GPS procedure :D

[Flyin'Dutch']

AA,

That is correct but practice learns that this is an area where they usually don't send a bill.

EA,

Thank you for chapter and verse, so FFF, there you have it, in the scenario depicted I think you will be therefore be struggling to stay VMC.

Not my idea of fun but I know there are people about who would happily launch into something like that.

FD

[Chilli Monster]

Departing IFR, and filing an IFR flight plan would probably help in getting a RAS, though I am not sure on how the system works with regards to routing IFR flight plans. Probably a LARS unit wouldn't get a copy. Every time I've pre-filed though, it certainly seems easier to get a RAS.
Pure co-incidence. Flight Plan filing has nothing to do with service received. If you say you're IFR you can get a RAS, but only then. Flight Plans (in the UK) only go to the centre's if you've routed airways, airfields of departure and destination, and anyone else that you may have addressed it to - though as most pilots leave the addressing to ATC then it normally only goes to who I've said above.

[RodgerF]

Quote:

3500 -RA SCT004 BKN006 OVC008

Quote

2 - Departure in these conditions is reasonable with an IR, bit daft with just an IMC (cloud conditions are well below the recommended minima for an IMC holder).

Why are the cloud conditions well below the minima for an IMC holder?
It depends on what approach systems are available. An ILS or NDB approach with a DH/MDH of 400' or less can be legitimately attempted by an IMC holder in these conditions. For the purposes of takeoff in a single CAP507 states that a cloud base of 1000' agl is the public transport minima but also says that takeoff with less than 600' cloudbase is not recommended.

[vintage ATCO]

Given the met. conditions stated, we would not issue a VFR clearance to fixed wing aircraft in Class D airspace.


VA

[Evo]

Why are the cloud conditions well below the minima for an IMC holder?


I did say recommended minima. With the weather given you could be flying into cloud at 400 feet, and "takeoff with less than 600' cloudbase is not recommended". Thom suggests that an average IMC holder should use considerably higher minima than those recommended.

I appreciate that the IMC covers a multitude of abilities - there's a huge difference between an IMC issued on the basis of an FAA IR and a bog-standard PPL/IMC like me - and there are IMC holders who could depart. It would probably be a bit daft for most of us. :)

[Timothy]

Although I don't know who Woss.... is, there is a paranoid side of me that is thinking that it is I who am being targetted by this thread, as I departed Biggin in exactly that METAR yesterday.

I would agree with much of what has been said, pointing out that I have an IR, the aircraft is a de-iced twin (though the freezing level yesterday was 4000'), there is an IAP and ATC at Biggin and that the weather at Farnborough was suitable for vanilla PPL VFR.

Keef is quite right (he knows me well) that the motivation for departing VFR is to avoiding route charges. I am perfectly happy to pay charges in a controlled environment (such as airways) (though I still don't understand why I, in my Aztec, should and a Seneca, or indeed Arrow, shouldn't) but I am damned if I will willingly pay for a service outside regulated airspace which is voluntary and sporadic.

W

[Chilli Monster]

EVO With the weather given you could be flying into cloud at 400 feet, and "takeoff with less than 600' cloudbase is not recommended".
Actually the cloudbase is 600' in the example. Definition of cloudbase being 'Lowest layer of cloud of BKN or greater, or first layer of cloud if nothing greater than SCT'. If the 'SCT' amount was only 3 oktas (SCT being 3 or 4) then it's quite concievable that you could avoid it quite happily.

Nothing wrong with the VFR departure as quoted and then redeclaring yourself IFR on departure. As class 'G' airspace does not require any form of IFR clearance then it's up to the pilot to fly iaw the Instrument Flight Rules, none of which require any form of ATC intervention unless requested by the pilot. It's like everything in flying - you make your own risk assesment and fly accordingly. If it was WCollins in this scenario then I don't have a problem with it knowing the man, the experience and the equipment involved, as well as the airspace. I would have quite happily done the same.

[bookworm]

Woss goin on..? asks a number of related but distinct questions. First the legality issues:

1: Is this departure legal under the VFR rules

To enter IMC requires (by definition) the flight to be conducted, at that point, under IFR. There is no reason why a flight should not change from being a VFR flight to an IFR flight at any point, from moments after take-off to moments before landing.

In controlled airspace, a clearance is required for IFR flight. Therefore the scenario described would be illegal, unless approved in advance by ATC in which case it would almost certainly be pointless.

Outside controlled airspace, a clearance is not required for IFR flight. Thus it would be perfectly legal to switch from VFR to IFR when required. The only wrinkle might be if the airport of departure had ATC, in which case the controller has the right to instruct the aircraft to maintain VFR within the ATZ. In those circumstances it would be necessary for the pilot to remain in VMC until outside the ATZ.

Now for the is-it-sensible? issue:

do you consider it sensible to depart in these conditions, fly IMC with no form of radar cover, and no way of avoiding other aircraft which may be in your path?

There seems to be a level of confusion about aircraft separation implicit in the question.

On the assumption that the flight is being conducted outside controlled airspace, there is no reason to believe that the flight would be better separated from other aircraft simply by virtue of being IFR rather than VFR. If radar is available, a radar service may (and probably should) be offered to VFR flights as well as IFR flights. If radar is not available, the IFR flight is separated only from other participating IFR flights. If there are none, or the pilot of the departing flight is aware of the other IFR flights known to ATC, then that minimal separtion service is no better than what the pilot can achieve with common sense.

Then the motive:

what reasons would a pilot choose for not departing IFR? Is there a worry about route charges or something similar?

I would imagine that might be the issue. Charges are applied to aircraft between 2 and 5.7 tons if any part of the flight is conducted under IFR, regardless of the service provided. If a flight departs VFR, it is less likely to find its way onto Eurocontrol's system.

Finally
do you consider these rules are clear, and understood fully by pilots or are they unduly confusing?

The complexity of regulations often go with the flexibility they offer. In this case a great deal of flexibility is offered compared with, for example, the German practice of simply banning IFR outside controlled airspace. If the complexity of the UK system troubles anyone, there is no reason why they should not simply decline to fly IFR outside controlled airspace.

[Flyin'Dutch']

CAAFU requires IIRC 1800m and 1000ft for exam flights in a single for an IR.

FD

[Tinstaafl]

If concerned about traffic & are OCTA then make a broadcast: Callsign/type, position, altitude & intention/next position & estimate.

That at least gives a 'heads up' to anyone nearby & on the freq. You can then coordinate your own separation.

[Chilli Monster]

Tinstaafl

And what frequency would you propose making this broadcast on?

[Rupert S]

although it may be legal, it sounds like very bad airmanship to do such a thing and very dangerous. I think it would be very foolish to fly in IMC with no radar cover.

[IO540]

Well it amazes me how much disinformation one gets from instructors.

I have been categorically told that an IFR departure cannot be done unless the ATCO is qualified to give it. You get it read to you just before lining up, you then read it back and say you are ready for departure. I never knew that you can depart IFR without talking to anybody. I know you can fly en-route IFR of course.

At my airfield, which is licensed after say 0830, you can depart VFR after 0800 but cannot do an IFR departure until 0830. I don't know if this is related to it being licensed, or related to a suitably qualified ATCO turning up at 0830.

Re the IMC Rating stuff, I don't want to drag out the old argument but I always succumb to temptation :O What is the difference between an IMCR pilot and an IR pilot, with the same currency (or lack of) in IMC and on type, in the same aircraft suitable for the job? The difference is that the IR one has sat a load of exams, perhaps many years ago. There is a lot of expired IMCR pilots but there is also a lot of expired IRs (including great many instructors).

[Chilli Monster]

Rupert S

Rather a sweeping statement if you don't mind me saying. There are times and places where you have to fly in IMC without a radar service. Outside of CAS this is a fact and there's nothing you can do about it. That's why there's such things as quadrantal / semi-circular rules - to reduce the risk. It's like I said earlier - you risk assess it and act in accordance with that assessment. It's neither good nor bad airmanship - just a fact of life.

IO540

Your instructor is technically right. Take a look at the UK AIP (AD1.3 is the relevant section). There it states what flight rules are applicable for each airfield, and any caveats that may apply. So - you can only depart and arrive VFR at some (mainly A/G / AFIS type airfields). The grey area is - at which point can you declare yourself en-rte and therefore go IFR ;) To be quite honest this table should really be re-labelled VMC/IMC because, as others have said, what about night flying, which is technically IFR (but which uses the 'clear of cloud and in sight of the surface' caveats of IFR at airfields which are not listed as IFR airfields!)

[Timothy]

although it may be legal, it sounds like very bad airmanship to do such a thing and very dangerous. I think it would be very foolish to fly in IMC with no radar cover.This chesnut comes up with boring regularity. Just have a look at the number of aircraft which have collided in the open FIR/Class G when in cloud in the last 50 years (= 0, to save you the trouble) compared to the number in VMC, or the number in controlled airspace and you will realise that IMC in uncontrolled airspace is the only safe place to be.

So, can I be excused from being foolish and dangerous please :O

W

[Rupert S]

Chilli Monster,
Perhaps I was a bit hastey in my reply - I should have said that one would be ill advised to fly in such conditions without a radar service if one was availible especially in congested areas (which I would imagine this thread is referring to).

[Keef]

If there's a radar service, and you're in IMC, using it is a good idea. It's not a bad idea in VMC either. I often get VFR traffic pointed out to me by LARS units. You can look and look and still not see. It's the low-down dark-coloured ones I have trouble spotting.

But I've flown (and been flown) many times under IFR in IMC in open FIR, with no radar or anything else, and wasn't worried. It's a big sky! Just avoid the honeypots.

[IO540]

Chilli Monster

Thank you for confirming what I thought, and my apologies to those instructors who told me what I said :O Mind you I still have to deal with the CFI (ATPL) who told me you can saturate a VOR (a VOR, not a DME) if you tune too many receivers to it...

I would transit to IFR as the zone boundary i.e. pretty well right away. But one won't get an RIS if below the minimum authorised RIS level for that radar unit, so in the conditions described one would be IMC by the time one gets any cover.

Except for the engine failure scenario (which assuming one can actually fly in IMC is statistically the only real risk) I would be quite happy to depart in those conditions - IF the destination and alternate are both clear.

What I don't know is whether the PILOT himself is able to phone the radar unit before departure, and get a squawk allocated.

[Chilli Monster]

I would transit to IFR as the zone boundary i.e. pretty well right away. But one won't get an RIS if below the minimum authorised RIS level for that radar unit, so in the conditions described one would be IMC by the time one gets any cover.
We don't lay down a minimum altitude for RIS, only RAS. At lower levels away from the radar head (1000ft per 10nm is a good rule of thumb for lower limits of cover) the service will be limited and the reason for limitation will be explained in the 'verbal contract' of service.
What I don't know is whether the PILOT himself is able to phone the radar unit before departure, and get a squawk allocated.
Nothing to stop you - but I wouldn't bother. There are many standing agreements between adjacent units regarding the verification and validation of squawks. You could end up in a position where you get airborne, wearing this pre given squawk, but your mode 'C' is out. Adjoining unit sees you wearing another units squawk, take it to be validated and verified (which it hasn't been) and promptly has an airmiss with you because the mode 'C' isn't what it appears to be.

Just call as soon as possible.

[Red Four]

In response to one of the original questions, one reason a pilot may prefer to depart on a VFR clearance rather than an IFR clearance, is to avoid ATC delay.

As an IFR departure, ATC would be required to separate you from other IFR traffic they are working as an Approach unit. Due to requirements of separation, then (particularly in a Procedural ATC environment), the delays can soon mount. A VFR departure does not have the requirement to be separated by ATC, so tend not to be delayed by waiting at the holding point waiting for separation to be acheived, as an IFR departure may be.

Now whether it is desirable on safety grounds for aircraft to depart as VFR in such conditions, is a different question. It certainly doesn't fill ATC with a warm glow of 'everything is all right' when such VFR departures immediately enter IMC on departure as they have not until then been required to separate that traffic from the other known IFR traffic. Apart from the effect on the separation of the (now IFR) departure, it may have also seriously reduced the separation established between other IFR flights that ATC is responsible for separating, but hadn't been expecting to have to separate from the VFR departure.

4

[drauk]

This discussion brings to my mind the fact that when I did my IMC flight test the examiner had me take off under the hood. I put the hood on at the departure hold and he did the taxi on to the threshold, at which point he handed over to me. It was a bit of a shock at the time because I'd never tried it with my instructor.

Is this a normal procedure for an IMC skills test? Any examiners care to comment on it?

[Flyin'Dutch']

Never heard that one before.

FD

[englishal]

Did it for the FAA IR, though don't think it is required for the flight test.

Believe it is meant to be part of the training ("instrument Takeoff"), the idea being to

"•Instrument takeoff provides proficiency and confidence necessary to execute instrument departures under conditions of low visibility and rain
•Prepares student for rapid change of flight from visual flight into IMC"

Cheers
EA

[Timothy]

Prepares student for rapid change of flight from visual flight into IMCI'd have thought that it would do quite the opposite. The transition from a visual take-off to instruments in very poor visibility is a difficult skill to learn and something that is very dangerous indeed if you get it wrong, particularly with a simultaneous engine failure, and I would have thought that practising and demonstrating that skill was more important than doing the whole takeoff run on instruments.

Incidentally, when I did my (CAA) IR training in the early 80's I was expected to do a landing entirely on instruments, not for the test but during training. The particular instructor, Dai Heather Hayes, wanted us to realise that if push came to shove it was more practical to land in zero vis than to eventually plough a furrow somewhere under the hold when the fuel ran out.

W

[ShyTorque]

Ah, Yes. Good old Dai, he did my CPLA checkride!

Forever practical. Far better to crash near the fire engines :ok:

Is he still around at Perth?

BTW, sometimes we are obliged to fly IFR in UK without a proper Radar service as there isn't always anyone to obtain a service from! Not ideal. We do have TCAS which helps a little provided others use their transponder and radios sensibly and fly quadrantals. Below the London TMA is a problem, no chance of a quadrantal but normally a radar service is available. But it seems there are an awful lot of aircraft out there NOT using Mode C in the London area...wonder why?

[Timothy]

I can think of a number of reasons:

No Mode C installed (quite common)
Mode C installed but u/s (very common)
Lack of training
Wish not to self incriminate

W

[troposurfer]

Er excuse me chaps, don't want to interrupt but my ATPL Air Law course taught me that......



VFR flights shall not take off or land at an aerodrome within a CTZ, ATZ or traffic pattern :

a) when cloud ceiling is less than 1500ft or;

b) when GROUND vis is less than 5000m.

You may be Authorised to take off and land under more marginal conditions but this requires an SVFR clearance from an ATCU.

I don't remember the figures on the original post exactly but a vis of about 3500 was quoted with various cloud layers at 400-800ft.

This does not represent a VFRable departure as far as I can tell. The mere fact you immediately wish call the flight IFR just after takeoff tells you the full story!

Imagine this scenario....... you had engine failure/problems at say 1500ft. you are probably 2-3 mins after takeoff in a low winged single with 8-10:1 glide ratio........what would you do?

Think about it.

There is a blanket of cloud below you (ovc800). Any Nav aids or a friendy ATC with radar to vector you back, that is if you have time to make the radio call.

Thankfully this forum allows pilots a chance to find out about these issues and many others. I may well be right off the mark with my own knowledge and someone more senior may be able to put me straight, but in my book caution is the best option.

Yes some of these VFR/IFR rules are confusing and can ofetn be interpreted in many different ways and I think that is a major problem both for pilots and the regulatory authorites ie JAA/CAA.

The AIPs and ANOs are not exactly easy reading and finding anything for reference purposes can take ages. In Australia the CASA (OZ CAA) produce a DAY VFR guide which includes virtually all the relevant air law for VFR flying. It even has a glossary and an index with page numbers for you to look thinks up 'at a glance'.

Maybe some clarification of what a VFR departure is needs doing by the CAA.

What do you think?

regards

Tropo

[Timothy]

Tropo

You may be right, but I have scanned ANO (http://www.hmso.gov.uk/si/si2000/20001562.htm) and Rules of the Air (http://www.hmso.gov.uk/si/si1996/Uksi_19961393_en_2.htm) and can't see such a regulation. Bookworm where are you? :oh:

I have looked up Fairoaks in the AIP and there are specific local limitations there that VFR aircraft must maintain surface contact in a minimum vis of 3km. Can I respectfully suggest that this limitation would not be specific to Fairoaks if it were a general rule?

I wonder what it was that your Air Law paper was getting at? Maybe to do with PT Ops? Actually there are stipulations in the ANO about PT, but they don't seem to include the ones you mention.

Finally, I can't really see that your admonition that it is not safe for a single to take off in poor conditions would be made any different for an IFR departure. Woss' point was about the choice of IFR and VFR. Your point is (if I understand) that it is not safe for a single to operate in IMC at all. There is no doubt that singles are permitted to take off in IMC under IFR, whatever your (and indeed my) opinion of the advisedness of doing that.

Forgive me if I have misunderstood.

W

[Circuit Basher]

WCollins / ShyTorque - Dai is certainly still a more or less permanent fixture at Perth!! Around 80% of the times I go there to fly, he's there!! He still has his Pitts; I have never flown with him, but a couple of the guys in my club have and reckon that it's the best hours instruction they've ever had! He certainly teaches pragmatic flying - not just reeling out the numbers, but tries to convey a deeper understanding of what the aircraft's up to.

[ShyTorque]

WCollins,

Don't see why the first 3 should be more common around London.... ;)

Number 4 seems favourite :rolleyes:

[IO540]

WCollins

You mention 3km vis for a VFR departure; however it seems clear to me that the conditions in the original question would make a plain-PPL case pretty reckless. It may be legally flyable but it probably would not be navigable.

So we are looking at IMCR or IR. As far as I know an IMCR pilot can do a "VFR" departure in 1800m vis.

I don't know about IR; what is the min vis for a VFR departure if there is no published RVR for that field?

[Timothy]

My guess is "Clear of cloud, in sight of the surface" provided you do less than 140kts until you convert to IFR.

But hey! What do I know?!?:uhoh:

W

[drauk]

Seems like the part of the original question which asked if the rules are confusing has at least been answered - agreement has not been reached so I guess they must be at least somewhat unclear to some people.

[Timothy]

drauk

Can I, with all humility, suggest that there is only confusion amongst those who have not read the ANO and ROTA recently, and that to those that have the situation is quite clear?

The best way of rectifying this would be for more people to read the rooles.

W

[englishal]

I'd have thought that it would do quite the opposite
The FAA don't think so :D

I think the training is designed so that a student starts to use the instruments early on, and not waiting until entering IMC, before they go instrument......

Cherio

[drauk]

WCollins, you're right, of course. But I find the course of this discussion somewhat interesting. Evo and FFF both thought the departure was legal, but weren't completely sure. IO540 thought it couldn't be an IFR departure because you couldn't do one at a small airfield, was corrected by various people and then Chilli Monster set them straight. Flyin'Dutch' said a VFR departure was not legal. Surely that amounts to some confusion?

And these aren't people that just post any old junk. These names, and your own, make posts which I tend to take notice of, or at least read very carefully, because in my experience they post well considered information. But I guess I'm just being lazy and reading the rules is the thing to do.

[Keef]

My concern, like WC's, is about the decision to change to IFR.

Bimbling along in glorious VMC, no problem. One little cloud - so I fly through it, still looking out the front and being "VFR".

As it gets cloudier/foggier, there comes a point when I should conclude this isn't VMC, and change to flying proper IFR in IMC. I've taught myself to announce (out loud) "Now flying IFR" and to DO that.

Sometimes it's 20 seconds after takeoff, sometimes part way through a long flight, but it's important to make that decision, quickly and firmly, and stick with it

I remember long years ago flying along just under a cloud layer, watching the treetops getting closer. I got quite uncomfortable, before I said "blow this" and climbed into the cloud.

The FAA IR test doesn't really do that - you know you're going to transition to IFR pretty soon, and have an "adjust time" while putting on the hood.

[Keef]

So why is there such confusion, on the part of obviously intelligent people who take the subject seriously? I think the answer lies in the difficulty in finding the answers!

I find the UK publications tortuous: I use the UKAIM and have great difficulty finding what I want in it. There's no index worthy of the name. Someone could provide a good service to pilots by compiling an index (or a whole book) that does things in logical (rather than legal) order and points to the relevant bit of the legislation for each decision a pilot needs to make. We don't all have Bookworm's fluent grasp of it all!

If I were looking to take off in marginal WX in the UK, I'd be looking at the definition of VFR in ANO Rule 26 (2)(b)(ii) - clear of cloud, in sight of surface, and in a flight vis of at least 1500 metres. I'd also be aware of the 500 foot rule (and the other mnimum height rules if they apply).

For an IMC rating, the takeoff minimum RVR is 1800 metres, so I can take off VFR or not take off at all. Therefore the issue of an IFR takeoff from an unlicensed (or non-ATC) airfield doesn't really get to me.

For the pilot with a valid IR, in the UK, it gets a bit more complex, depending on the aircraft and the airfield equipment. UKAIP AD 1.1 section 4 sets it out.

For a private flight in a single, there are no stipulated minima other than "adequate to ensure a high probability of a successful forced landing being made should a failure of the engine occur after takeoff. It should be noted that the minima for take-off by commercial air transport aeroplanes is 1000 feet cloud ceiling and 1800m RVR." So if you took off in less than those, the CAA would have a case to prosecute for hazarding an aircraft.

WCollins in his twin could, in theory, takeoff in anything down to 150m RVR if all the information and lighting equipment needed is present. (UKAIP AD 1.1 Section 4.1.2).

As to IFR departures from unlicensed fields - I don't know. I couldn't find anything about that (my copy of the UKAIM doesn't have AD 1.3 that CM referred to). Personally, I wouldn't do it (couldn't, with the IMC rating).

[Timothy]

Keef

The trouble is that if you rely on a synopsis you can end up with misunderstandings. It is very common for people to say "...but is says in Thom..." or (pace Tropo) "...in my ATPL course material...".

If you go back to the source you read the rooles as they will be applied in Court.

Will

[englishal]

It should be noted that the minima for take-off by commercial air transport aeroplanes is 1000 feet cloud ceiling and 1800m RVR
Isn't the RVR take off requirement for commercial ops the same as the RVR detailed on the approach plate at that airfield (or visibility translated into RVR)? In the states it is, if minimums are less than the approach minimums, then take off by commercial operators are banned, even though John Doe in his C152 could quite legally (though probably not wisely) take off.

I took off from Edinburgh with an RVR of 750m, I was following a BA 757....

CU:D

[Edited becasue I just re-read and assume that you're talking about a field without a prescribed IAP procedure....:D]

[Timothy]

Isn't the RVR take off requirement for commercial ops the same as the RVR detailed on the approach plate at that airfieldNo.

The ANO is fairly loose on the subject, placing the responsibility in the hands of the operator. PT Ops Manuals, in order to be approved, will contain two stipulations:

One has to do with the lighting on the runway, and the acceptable vis. For Keef's 150m you need centreline lights for example. An RVR of around 175-250m would be typical for a Biggin or Southend, from memory.

The other has to do with getting back on the ground in the event of an emergency. Typically you have to ensure that there is somewhere above minima (and forecast to remain so) within 30 mins flying time, flying time being calculated on the basis of an engine failure.

Will

[Keef]

EA

I'm quoting directly from the "law" (or the AIP anyway). The 1000 feet ceiling/1800m RVR is, I understand, for single-engined PT Ops. I didn't look for it elsewhere since it was stated in the UKAIP at AD 1.1 Section 4.

If you took off from Edinburgh in a single, non-PT, with 750m RVR, you were legal. Likewise if PT but in a twin. If it was PT and a single, I fear you might not have been.

Will

Quite - but being sneaky, I was using the UKAIM which reproduces verbatim the "law".

Yes, 150m is the lowest minimum on the page and requires a full kit of lighting etc.

I didn't look up the US equivalent rules - it's all in the FAR.AIM for them as wants it.

[bookworm]

Bookworm where are you?

Recovering from the Xmas goose and associated excesses in ED-land. Is there a smiley for that? :ooh:

I'm touched you missed me but can't add much to what has been said.

To Troposurfer's point, there is an ICAO rule that forbids VFR arrivals/departures in a control zone when the visibility is less than 5 km and the cloud ceiling is less than 1500 ft unless a clearance is obtained from ATC. But this rule is not used by the UK, since every CTR requires a clearance anyway. There is an equivalent for non-radio aircraft, Rule 16(2) which sets minima (at the destination) for departure.

The ICAO rule is somewhat ambiguous:

"shall not take off or land within a control zone, or enter the aerodrome traffic zone or traffic pattern, unless..."

My interpretation is that this applies only within control zones, and that the alternatives are activities within the CTR that are not permitted.

[vintage ATCO]

Bookworm

We wouldn't issue a VFR clearance in a class D CTR if the vis is less than 5km and/or cloud ceiling less than 1500ft.

VA

[Timothy]

VA

Sure....but Tropo was saying that the same rule applies to any airfield with an ATZ, which, I am sure you would agree, ain't so.

Will

[vintage ATCO]

WC, I always agree with you! :eek: :D :D :D

[bookworm]

We wouldn't issue a VFR clearance in a class D CTR if the ... cloud ceiling less than 1500ft

Is that a MATS Pt I thing? Or specific to a particular airport?

[valenii]

The FAA IR test doesn't really do that - you know you're going to transition to IFR pretty soon, and have an "adjust time" while putting on the hood.

My FAA IR instructor often made me practice "under the hood" takeoffs, using the DI to keep runway heading until rotate (and after too!).

The FAA system is dependent on the instructors "signing you off" as ready, the test can't cover everything....

Ian

[Keef]

Yes, but it still doesn't prepare you for the decision-making process. You're already in IMC...

[vintage ATCO]

bookworm

MATS Pt 1 Section 3 Chapter 1 page 5

but read the corrigendum letter at the front of the doc.


VA

[bookworm]

I don't know about corrigiendum letters as such. I've got the downloadable CAP 493 with Amendment 57. It mentions no VFR clearances when the vis is below 5000 m but I can't see anything about cloud ceiling.

I'm not just trying to be nitpicky about details, though you know too well that's in my nature :). Under ICAO rules for controlled airspace, the minimum VFR level permitted is 500 ft and the minimum vertical separation from cloud is 1000 ft. Thus VFR is impossible if the ceiling is less than 1500 ft. The UK has neither rule and so VFR is, in principle, possible with such a ceiling.

The ICAO rule anticipates class E control zones where a clearance wouldn't otherwise be required. It forces a flight in such circumstances to get a SVFR clearance. In the UK, the same can be achieved by instructions to ATC, as all the flights in the CTR require a clearance.

[Warped Factor]

bookworm,

The latest downloadable Pt 1, which includes the relevant corrigendum letter, is the one with ammendment 59 incorporated.

Available from the CAA website.

WF.

[bookworm]

Thank you. I'm now totally baffled. Amendment 59 reads:


8.5 When the reported meteorological visibility at the aerodrome falls below 5000 m, and/or the cloud ceiling is less than 1500 feet, pilots of aircraft, other than helicopters, operating under VFR inbound to, or outbound from airfields situated in Class D control zones must be advised and their intentions sought. No further VFR clearances are to be issued to any inbound or outbound traffic, in these circumstances, until such time as the reported meteorological visibility at the aerodrome reaches or exceeds 5000m and the cloud ceiling is 1500 feet or above.


(change bars indicate that the parts about cloud ceiling are insertions in Amendment 59)

The corrigiendum reads:


There is an error in Amendment 59 to CAP 493 Manual of Air Traffic Services (MATS) Part 1, Section 3, Chapter 1, page 5, paragraph 8.5. The last sentence should be corrected to finish with a full stop after “exceeds 5000 m” and the remaining words deleted.

“No further VFR clearances are to be issued to any inbound or outbound traffic, in these circumstances, until such time as the reported meteorological visibility at the aerodrome reaches or exceeds 5000m. [and the cloud ceiling is 1500 feet or above].”


So this raises two questions:

1) Why would they insert the 1500 ft bit? [Don't tell me -- it was that bl:*:*dy ICAO safety audit, wasn't it...]

2) Why would they delete it in the second part but not the first?

It's really quite awful drafting. Reading the two bits together, does this mean, as Vintage ATCO suggests, that there is a 1500 ft ceiling limit on VFR in the CTR or not? :confused:

[vintage ATCO]

We are not permitted to issue a VFR clearance (in a Class D CTR) if the vis is less than 5km and/or the cloud ceiling is less than 1500ft.

I don't know why the second 1500ft was removed.

[Woss goin on..?]

Finally had a chance to study all the views to this thread after a busy xmas. Hope all had a good time and are still within MTOW!

Judging by all the detailed posts, it seems that there certainly is confusion within the VFR regulations but these confusions seem to concern mainly whether or not a take off in the conditions stated is legal (it appears to be). But is the rest of the flight legal and how do you manage the flight if it subsequently becomes IMC/IFR.

Even though a departure may be legal in those conditions, the en route phase certainly would not be given that maintaining clear of clouds would invariably cause a breach of Rule 5.

So, why depart then VFR? As W Collins clearly points out, a big reason appears to be the wish not to incur route charges and who would not agree? You are not receiving any services so why pay? Perhaps then we should take this up with the powers that be but my life is not long enough to wrestle that one out of CAA, Brussels, whoever....

But is it sensible to depart without any prior arrangement with a radar unit set up? What about the possibility that somebody just might be coming the other way? To quote W Collins again, there have been no instances of collision whilst flying IMC outside of controlled airspace....this I presume is true but I have knowledge of several instances recently where collisions appear to have been narrowly avoided. Circumstances varied but some were saved by TCAS, some by timely radio calls coincidentally and some by radar. So the danger is there. The 'big sky' theory pointed out by some contributors to this post is true...but the sods law also applies.

What about radar then? At best in the UK coverage is patchy and although the controllers have the best of intentions, invariably you are offered 'Radar Information limited due to range,altitude,controller workload or poor radar performance'. Incidentally, I thought RIS or RAS was available.....where is the official definition of 'Limited radar'?!! Indeed, some of the close ones noted have been receiving a service so still you are not guaranteed safety but arming oneself with all the tools available must surely increse your safety margin.

In respect of W Collins worry that he was the 'target' of this post, this is not the case. The Metar given was a representative one used as an example. Indeed, I have seen departures in conditions worse than shown, which is the impetus for this thread. However, It is recognised that there is a difference between the crazies who launch ill equipped and under rated in a 150 to that of the experienced IR pilots in the right equipment who have contributed to this thread.

My summary then...no matter how experienced, or what you are flying, get a radar service if its available and you're IMC....the route charge (even if it ever finds you) will be small change if it's helped you avoid hitting me coming the other way! And turn that Mode C on!

Woss.

ps. Is it true that you cannot fly IMC outside controlled airspace in France?

[Chilli Monster]

but I have knowledge of several instances recently where collisions appear to have been narrowly avoided. Circumstances varied but some were saved by TCAS, some by timely radio calls coincidentally and some by radar.
But - how do you know these 'instances' would have resulted in collisions or merely the aircraft being a bit too 'adjacent' than the occupants would have liked. You only know aircraft were in danger of colliding by either a) it actually happening or b) accurate simulation / modelling after the event. As such you can't really make the statement above - it just isn't true.
I thought RIS or RAS was available.....where is the official definition of 'Limited radar'?!!
MATS Pt1, Section 1, Chapter 5

1.6 Limiting a Service

1.6.1 Outside controlled airspace in circumstances where controllers cannot continue to provide the following primary requirements:
a) traffic information and traffic avoidance in respect of all conflicting unknown aircraft for a radar advisory service; and
b) traffic information in respect of all conflicting unknown aircraft for a radar information service, controllers may elect to continue to give the service by limiting the extent to which it is provided.

1.6.2 Controllers must inform pilots when they limit the service and ensure that pilots are made fully aware of the implications of any limitation.

1.6.3 In particular the service should be limited when:
a) the aircraft is operating within 10 miles* of:
i) the edge of the radar display;
ii) weather clutter; or
iii) permanent echoes.
b) the aircraft is operating in an area of high traffic density;
c) the aircraft is operating near to the limits of solid radar cover; or
d) The service is being provided using secondary radar only.
* Except where the range selected (e.g. 3, 10, 15 miles) will not enable these criteria to be met during an approach to an aerodrome.

[Woss goin on..?]

Chiil Monster

Thank you for the MATS info re Limited Radar.

But - how do you know these 'instances' would have resulted in collisions or merely the aircraft being a bit too 'adjacent' than the occupants would have liked. You only know aircraft were in danger of colliding by either a) it actually happening or b) accurate simulation / modelling after the event. As such you can't really make the statement above - it just isn't true.

If you don't mind me saying so, this statement is a bit daft. Obviously you don't know in all cases if a collision would have occurred. But given that two aircraft in IMC are flying converging tracks neither of which are receiving separation from an ATC unit, it would seem that there is a risk of collision even if thankfully it did not occur. It does not matter how 'adjacent' they are: they are not separated by anyone, they are not talking to anyone so the risk is there.

[Chilli Monster]

Woss But given that two aircraft in IMC are flying converging tracks neither of which are receiving separation from an ATC unit, it would seem that there is a risk of collision even if thankfully it did not occur.
But you didn't say that originally. You said but I have knowledge of several instances recently where collisions appear to have been narrowly avoided. Circumstances varied but some were saved by TCAS, some by timely radio calls coincidentally and some by radar. And I stick by my original answer. It's not daft unless refuted by FACTS and hearsay doesn't constitute fact. If you know of such circumstances then by all means enlighten us - but 'knowing' and 'summising' which is what, to be honest, your original statement is nearer to I would think, are two totally separate things. Your use of the word 'appear' would back that up.

I mentioned simulation/modelling of the events to derive information on whether the collision would have happened. That's because that is what the UK Airprox board is there for and what they do. Leaving them as the final arbiters of whether a collision would have taken place rather than summising whether it would is a far more sensible idea in my honest opinion. If those reports are what you're referring to as the possibles that you know of then fair enough - but if you're referring to other events then we're back to the summising verses fact situation.

Just because aircraft aren't separated doesn't mean that they're going to hit. There was such a thing on my procedural course as a 'technical' loss of separation. The aircraft may have been 20 miles apart - but if you didn't have in place a laid down method of separation as per MATS pt 1 then it was deemed a technical loss, even though they wouldn't hit in a month of sundays.

Facts count, nothing else.

[bookworm]

We are not permitted to issue a VFR clearance (in a Class D CTR) if the vis is less than 5km and/or the cloud ceiling is less than 1500ft.

But that's not what it says in MATS Pt 1. In the corrected amended :) form, it says (first sentence) that you must advise VFR flights if the vis drops below 5000 m or the ceiling is less than 1500 ft. But (second sentence) if the latter is the case and the visibility is at or above 5000 m, you can issue a VFR clearance.

[TheFox]

Bookworm, actually vintage atco is correct. The CAA has got its self into a it of a muddle and have amended the ammedment to the the ammendment and my understanding is if the ceiling is below 1500ft you cant issue a vfr clearance to an aircraft taking off and landing in an airport in class D.

So this has been ammended again and the rest of the sentance put back in.


The corrigiendum reads:


quote:
--------------------------------------------------------------------------------

There is an error in Amendment 59 to CAP 493 Manual of Air Traffic Services (MATS) Part 1, Section 3, Chapter 1, page 5, paragraph 8.5. The last sentence should be corrected to finish with a full stop after “exceeds 5000 m” and the remaining words deleted.

“No further VFR clearances are to be issued to any inbound or outbound traffic, in these circumstances, until such time as the reported meteorological visibility at the aerodrome reaches or exceeds 5000m. [and the cloud ceiling is 1500 feet or above].”

--------------------------------------------------------------------------------

[bookworm]

CAA has got its self into a it of a muddle and have amended the ammedment to the the ammendment

OK, I think we should stop there. :confused: :)

[Timothy]

Bookworm, I trust that you meant that the discussion on CTRs should stop there and not the whole thread, cos I would like to come back to the discussion between Woss and Chilli.

The fact of the matter is that no such collision has taken place in UK airspace since the war. There is no better argument on risk than the actuarial one.

Some ATCOs and and Authorities seem to treat a "loss of separation" as seriously as a collision. This is like my wife's reaction to losing a child in the park. Just because you can't see him doesn't necessarily mean that he has been abducted or run-over, just as loss of separation doesn't mean the worst has happened.

I still feel safer in the class G corridor between BIG and OCK in a 2000' cloudbase at 2300' than I do at 1900'...and I believe that feeling of safety to be justified by the realities of the situation.

Will

[vintage ATCO]

Some ATCOs and and Authorities seem to treat a "loss of separation" as seriously as a collision.

Nah, a miss is as good as 3 miles. . . . . ;)

[Whipping Boy's SATCO]

I don't think its the ATCOs who necessarily treat a minor erosion as seriously as a collision, its more likely those pesky automated computer systems and the associated mountain of paperwork.

[S-Works]

I had a near miss yesterday, flying IFR from Beccles to Leicester in the snow and god knows what else another aircraft apparantly not flying a Quadrantal rule passed over the top at me by no more than 50ft. Made my bum clench a little a bit!

Forwardn viz at the time was around 250-500m.

The big skies theory is great if everyone flies to the same set of rules, unfortunatly yesterday it proves that they do not!

Unfortunatly all of the LARS units that I flew over were closed as well which mad a RADAR service impossible. I cant believe the want GA to pay for LARS!

Still a near miss is better than a hit!

[Timothy]

bose

I rest my case.....you didn't hit him :O

It is very difficult to get two aeroplanes in the same place at the same time unless they are over a beacon at a fixed altitude (either whole numbers of 500' or scud running) which is why I avoid both. :E

Will

[bookworm]

I had a near miss yesterday, flying IFR from Beccles to Leicester in the snow and god knows what else another aircraft apparantly not flying a Quadrantal rule passed over the top at me by no more than 50ft. Made my bum clench a little a bit!

Forwardn viz at the time was around 250-500m.

The big skies theory is great if everyone flies to the same set of rules, unfortunatly yesterday it proves that they do not!

So with 250 m forward vis you were able to ascertain that this aircraft, which you observed for, ooh about 4 seconds, was in level flight, not climbing or descending, and was therefore breaking the quadrantal rule? :)

[IO540]

bose-x

I am not sure that compliancewith the quad rule reduces the probability of a mid-air (implying a fatal accident).

It would make an interesting exercise in probability theory to work out whether IN IMC a mid-air is more or less likely between two objects flying head-on or the same two objects flying in the same direction.

I don't think the case is at all obvious. My feeling is that there is no difference at all.

(I am assuming that a 150kt plane going up the back of a 100kt one will be as good as a head-on)

If there is SOME visibility, then the quad rule should mean you have more time to see the other one. But given the poor visibility of GA planes (which is something all pilots and passengers notice pretty well right away) I don't think this is a factor unless the vis is a lot better than 250m. Also if somebody is being smart and is flying in marginal VMC with their landing/taxi lights on, you won't see those from behind. Also if somebody is closing with you at say a 20deg angle you probably won't see them anyway because few pilots twist their neck that far when looking for traffic.

I think by far the main benefit of the quad rule is for airliners: with TCAS you get a lot more time to act. But we all know that in GA a lot of people don't have transponders, or if they do they have them turned off. I flew today for 30 mins under an RIS, saw not one of 5 or so targets, and not one of them had Mode C on (I was VMC on top at FL050 and they were probably below).

[S-Works]

Bookworm,

I am sorry but you twisted my statement I said APPARANTLY not flying a quadrantal, I did not say that anything had been BROKEN. The other aircraft appeared to be in straight and level flight for the few short seconds that I saw him and made no attempt at avoiding action so I would guess did not see me.

I was flying at FL45 heading 290.

I was not making a complaint about the other aircraft who could well have been climbing or decscending, I was merely making an observation about a near miss.

My point was that despite this near miss in the open FIR without radar it was still a miss.

[Timothy]

I think by far the main benefit of the quad rule is for airliners: with TCAS you get a lot more time to act.Um...where to start? :confused:

The Quadrantal rule was there long before airways and radar was universal, and was mainly for separating Doves and DC4s.

Airliners nearly all fly on airways nearly all the time. The Quadrantal rule does not apply to airways.

The Quadrantal rule preceded TCAS by a long, long time (let's guess fifty years.)

No, the quadrantal rule is there to reduce the probability of collisions. My own view is that if aircraft flew at a level determined by the last letter of its registration (thus introducing more randomness) it would be more effective, but, as I keep saying, there really is no problem. It ain't bust, let's not fix it.

Will

[bookworm]

I am sorry but you twisted my statement I said APPARANTLY not flying a quadrantal, I did not say that anything had been BROKEN.

I interpreted your comment:

The big skies theory is great if everyone flies to the same set of rules, unfortunatly yesterday it proves that they do not!

as suggesting that the other aircraft wasn't flying to the rules. But I take your main point.


WCollins wrote:
My own view is that if aircraft flew at a level determined by the last letter of its registration (thus introducing more randomness) it would be more effective, but, as I keep saying, there really is no problem.

I heard of a proposal many years ago that the big hand on the altimeter should match your heading (e.g. NE at 1000s + 125 ft). It provides only 500 ft of separation between opoosite direction, but it seems to meet sensible criteria. Perhaps we should add a die to the requirements of Scehdule 4 :)

Finally, IO540 wrote:
It would make an interesting exercise in probability theory to work out whether IN IMC a mid-air is more or less likely between two objects flying head-on or the same two objects flying in the same direction.

It's a good question. One way of looking at it might be to consider a flight 1 from A to B taking 2 hours at 150 kt, and a flight 2 from B to A, taking 3 hours at 100 kt. They will pass if the difference in their departure times is in a 5 hour window (i.e. if 1 leaves at 1400, it will conflict if 2 departed between 1100 and 1600). If you reverse flight 2, it will conflict only if it leaves in a 1 hour window (1300 to 1400).

While that's a 1-dimensional look at a complex problem, but I think it illustrates the point.

[IO540]

bookworm

That's an interesting way of looking at it. I am not qualified in this field so better not say any more, but I feel that a better way to look at it is to start with an assumption that two planes are already inside a sphere of a given radius, say 1 mile, and work out if they are more or less likely to hit depending on the rules they follow.

Anyway, the French use the semi rule, which appears to discard half of whatever advantage there is.

[Timothy]

Perhaps we should add a die to the requirements of Scehdule 4Like the Dice Man, you mean? But he ends up raping and murdering and all sorts of terrible things, then I gave up reading it in disgust.

Actually, going back to Woss' original point, maybe we should make the VFR/IFR choice based entirely on the throw of a die :ok:

Will

[troposurfer]

Is this departure IFR or VFR? That is the question!


And the answer is ....................er............somewhat ambiguous!


Very many versions exist of ICAO/ATC or CAA/JAA regulations from the ANO/AIPs.


The AIM does a good job of collating all the relevant Air Law material to give the private pilot a good point of reference for all Air Law/legislation issues, but it does not seem to go far enough. It could be a little more coherent.....with an INDEX too!

I can't remember which poster said I should stop quoting my ATPL material and look at the rules, what are you on about?

If you KNEW I was wrong just say it and quote me the ANO/AIP/JAR/ICAO Doc reference and I will go and look it up!
My JAR/CAA Approved ATPL course has to be kept up to date and correct, ratified and inspected regularly by the UK CAA.

The school I use was inspected while I was there in OCT 2003. Why would the CAA let such a closely monitored and regulated organisation diseminate incorrect information?


I quoted (in good faith) the ICAO based JAA approved notes saying that VFR departures should not be made with

a) cloubase less than 1500ft (aal)

b) and vis below 5000m

In CTR/ATZ or traffic patterns

The 2002/2003 AIM says (and may now be out of date)

AIP 4.1.1.2(pg 274)

the minima for SE aeroplanes should be adequate to ensure a HIGH PROBABILITY of a successful landing being made should engine failure occur after take-off.

It goes on to say that minima for commercial ops is 1000ft cloud ceiling and RVR 1800m as another poster quoted earlier.


I am not trying to tell the original poster that he took off illegally or anything such. What I am trying to tell others who may be reading and of less experience (ie PPLs or recent IMCs) that caution is the best option and that was the basis of the scenario in my previous post. EFATO SE in IMC after declaring a VFR DEP then entering IMC shortly after takeoff.

Taking off "into-the-soup" VFR (then IFR) at an uncontrolled airfield with no flightplan is foolhardy at best.

A better example should be being set to the other low hours PPL/IMC pilots on the forum whose last guidance was their flying instructor.

Just think how you might explain the loss of an aircraft/freind or loved one after taking off in marginal conditions. The CAA seems only too happy to prosecute these persons these days not including the personal injury fraternity.

If in doubt and the ATC or a more learned aviator says....DON'T.

Then don't. Caution=best option.


Regards

Tropo

Ps Happy New Year to you all!!!!!!!!!!!!!

[Timothy]

I can't remember which poster said I should stop quoting my ATPL material and look at the rules, what are you on about?That would be me, and what I was on about was that you should stop quoting your ATPL material and look at the rules.If you KNEW I was wrong just say it and quote me the ANO/AIP/JAR/ICAO Doc reference and I will go and look it up! I did that, though it is not in my nature to be didactic and brusque, so I put it rather more nicely. I told you that I had scoured the ANO and RotA and there was no reference to the figures you quoted. I was even helpful enough to give you links to the relevant legislation so that you could check for yourself. The trouble with my quoting chapter and verse is that the rule you mention just ain't there. What if I told you that there was a law that brown poodles may not go into Royal Parks on Thursdays, and when you said that you could find no such regulation I said "If you KNOW that, then quote the regulation."?Taking off "into-the-soup" VFR (then IFR) at an uncontrolled airfield with no flightplan is foolhardy at best.It is how many, many IFR flights take place. GA is strongly discouraged from using the big, grown up airfields which are connected to controlled airspace, and ends up in the Fairoaks, Blackbushes, Elstrees and Biggins of this world, from which there is no "right" to a radar service, it is only available in the gift of controllers at Farnborough, Luton or Thames, if they have time. As you would be told if you went onto the ATC forum, an FPL is of almost zero safety value outside controlled airspace.

It is great that you have so much faith in your ATPL course notes, but I fear that you will find, once you have been out in the real world for a bit, that it is not as black and white as the printed page.

Will

[englishal]

I think part of the ambiguity of deciding whether to fly VFR or IFR comes from the airspace system. If the airspace was set up to facilitate easy and safe IFR flights, and flight plan filing by GA pilots using an IMC rating, then it would take much of the uncertaintaty out of whether one should fly VFR or IFR, which would increase safety and help the pilot in his/her aeronautical decision making process.

Heres and idea......why not re-label all airspace (within reason) above say FL50, and below FL100 Class E, so an ATC clearance while operating under IFR could be given.....No clearance would be required for VFR flight. Overhead 'busy' airports, this Class E could become Class D, so ATC clearance would be required for VFR flight. Existing Class A low altitude airways could be re-labeled Class D if it were to make people happy, then at least VFR pilots could enter under control of ATC......

While we're at it, employ more ATC controllers, link all the radar data from military installations and civil stations and pipe it into one room in the south, and one in the north (lets call them London Lower Airspace approach control and Scottish Lower airspace approach control), and hey presto every one is happy :D

Am I getting carried away? :D

CU
EA

[Timothy]

Am I getting carried away?Only with the thought that anything might actually happen :p

It is great to campaign for more expenditure on ATC infrastructure, but the fact is that ATC is now (in the UK) an almost exclusively commercial matter, and I cannot see NATS and SERCO tripping over each other to bid to invest in control systems and controllers to handle what will be almost exclusively non-paying users (because they are below 2T).

If you impose charges on all IFR flights (of whatever weight) you will find that the majority do as I do and fly in such a way as to mitigate or eliminate charges (in your model that will mean below FL50) thus reducing any income to the service provider.

Will

[FlyingForFun]

why not re-label all airspace (within reason) above say FL50, and below FL100 Class E, so an ATC clearance while operating under IFR could be given..... etc etc etcWhat, and actually use the different classes of airspace for what they were intended??? :eek: :eek: :eek:

It'll never happen.

FFF
---------------

[2Donkeys]

Not long now in any case before ICAO moves on from the A-G airspace classification system and into a simpler model.

It'll be interesting to see what the DAP makes of that in the context of the UK's airspace system.

2D

[rustle]

It'll be interesting to see what the DAP makes of that in the context of the UK's airspace system

Make it all "N" :D

Are you flying Saturday, 2D?

[Whipping Boy's SATCO]

2Ds, I'll let you know in a couple of weeks!

[2Donkeys]

2Ds, I'll let you know in a couple of weeks!

I'm counting on it! Good luck with the job :D

2D

[TheKentishFledgling]

Not long now in any case before ICAO moves on from the A-G airspace classification system and into a simpler model.

Do you know roughly how it'll be done, 2Donks?

tKF

[2Donkeys]

Its a long way off tFK, but in essence it is proposed to divide airspace into areas of "Known Traffic" (Class K) and Unknown (U).

The implications for separation adn control in class K are clearly somewhat different to Class U. Much more than that varies somewhat depending on where you read it. The bottom line is

- fewer airspace classes
- greater harmonisation of ATC service
- less confusion.


Worth holding you breath for perhaps ;)

2D

[DFC]

Troposurtfer,

The ICAO requirement you quote requiring 1500ft ceiling for VFR flights only applies within control zones. The logic being that since under ICAO, you may not fly lower than 500ft AGL and in controlled airspace you must be 1000ft vertically from cloud, it would not be legal to depart VFR unless you could both reach 500ft agl and be 1000ft below the cloud. That is ICAO, not UK which does not have the same 500ft ASFC requirement or the 1000ft vertically from cloud requirement in the lower controlled airspace.


Getting back to the priginal matter;

Logically, I think....who in their right mind would depart VFR into such conditions.

There is no reason for not departing IFR. Even if one wished to remain "visual" until a radar service was established, there is absolutely noting wrong with departing IFR but remaining visual...check out IFR minimum height requirements and the exemption for being visual below 3000ft etc.

To look at the situation from a post accident point of view, a review of the decision to depart VFR and then soon after fly IFR would place much emphasis on the prior planning made by the pilot and comparing the actual point of entry into IMC with the planned point of entry into IMC.

Looking the the situation from the "other VFR pilot" point of view........can one honestly say that two VFR flights in such conditions could if they saw each other in good time, manoeuvere suficiently to comply with the rules for avoiding collisions while at the same time remaining VMC?

It is the same as driving down a twisting busy country road at 60mph...where the legal speed limit is 60mph......but one would be deemed reckless to drive so fast.

Regards,

DFC

[Timothy]

There is no reason for not departing IFR.At least two have been given earlier in this thread.

All these big "reckless", "foolhardy", "dangerous" words are simply silly. In the real world of departing an airfield that is not in a CTR and doesn't have radar there is absolutely no difference in the safety of departing VFR or IFR. Known traffic only extends to 2.5 miles from the ARP, there could easily be unknown traffic crossing the take-off path whichever set of rules you declare.

I fear that there is a considerable amount of prejudice and a considerable lack of knowledge and experience being shown in this thread, some from people who equate IFR with controlled airspace and some from people who haven't got there yet.

Maybe we can tone down the accusations if we want a reasonable discussion.

Will

[IO540]

CAN you depart "IFR" from a non-ATC airfield, anyway? You can't be in receipt of IFR departure instructions, for a start.

The originally described scenario is perfectly OK for a departure, whatever one calls it, provided the pilot is capable of instrument flight. If not, he almost certainly won't get very far.

The additional risk (relative to departing from the same place in say a higher cloudbase) is that in the event of a SEP engine failure one won't have much time to look for a field. I departed from the Scilly Isles once in probably 200ft cloudbase but there is only water at the end of the runway...

[2Donkeys]

CAN you depart "IFR" from a non-ATC airfield, anyway? You can't be in receipt of IFR departure instructions, for a start.

Yes.

It is not mandatory to be under a clearance to operate IFR outside controlled airspace. If the departure is made, remaining clear of controlled airspace, then the fact that the A/G Operator cannot give you a clearance is neither here nor there.

The Rules to be obeyed under IFR are set out in the Rules of the Air.

2D

[rustle]

2Ds quoth: ...but in essence it is proposed to divide airspace into areas of "Known Traffic" (Class K) and Unknown (U).

I thought the "known traffic environment" would be class "N" - hence my comment previously :O

[2Donkeys]

Rustle

You may be right. I have documents here that call it numerous things :D

I felt more comfortable defendning the choice of the letter "K" when describing a concept spelled "K N O W N" though.

It was my understanding that N was Intended Traffic Environment and that U was Unknown.

2D

[bookworm]

IIRC N is iNtended, in other words ATC not only knows about the traffic but knows its intentions, for example from Mode S enhanced data.

[rustle]

It seems you two could be right :O

Just had a look at the PPL/IR Europe mag:

http://www.pplir.org/journals/old/InstrumentPilot34.pdf

(page 15)

Which, whilst not authoritative, is informative :D

Since it is an old issue of "Instrument Pilot" non-members can download and read it

[Timothy]

You can't be in receipt of IFR departure instructions, for a start.AFISOs can, and very often do, read IFR clearances issued by London Control.

You can take off from a farmer's strip IFR, fly 200 miles IFR, and land in VMC at another strip without ever mentioning it to anyone, whether by FPL, telephone or radio, providing you remain clear of regulated airspace.

And remember a few things before we have more expletives about such a trip:

IFR does not necessarily imply IMC
The need to fly IFR might be that you are flying at 500' below a 4000' cloud base in 30km vis (that's IMC!)
Even if you are fully IMC all the way (except the first 500' and the last 1500', say) you are statistically infinitely less likely to have a mid-air than someone else doing the same thing VFR on a gin-clear day.

Will

[IO540]

2donkeys / wcollins

Interesting - I didn't know that you get the non-ATC airfield radio operator to telephone London Control (or who-ever else). That's news to me. What if it is a farm strip? You presumably call them yourself.

Of course none of this means anything safety-wise because at best one is going to get procedural separation from known traffic. In a free for all airfield you won't get even that.

So, given that departing "IFR" is likely to mean absolutely nothing, why not depart VFR and change to IFR on the first call to the proper ATCU? I suppose having a pre-assigned squawk saves a bit of time :O

Having been to plenty of free for all airfields, I think the chance of a collision in the conditions described is far less than on a clear day!

It's been an interesting debate on terminology :O

[2Donkeys]

The normal procedure for an airways IFR departure from an uncontrolled field, does not vary much.

If the field is A/G or FISO controlled the clearance will often sound like this :

"London Control instructs N33NW to remain outside controlled airspace, squawk 1234, and to contact xxx.xx when ready"

Where the field is a farm strip, you could telephone for some sort of clearance, but it is more common to take-off and use either London Information or a local LARS/Radar unit to negotiate your entry into controlled airspace.

Getting a clearance straight into controlled airspace from the ground under either set of circumstances is vanishingly rare because of the airspace that such a clearance would tie up. This is despite it being common practice in the US with its somewhat different airspace structure.


Whether you deem yourself to be IFR or VFR before receiving your clearance into controlled airspace is a decision you take based primarily on the prevailing weather conditions.

2D

[owenlars]

2 Donkeys has it spot on and London Inf or the likes of Thames and Farnborough are always very helpful an efficient in activating flight plans in the absence of ATC at an airfield.

The main reason for not leaving VFR and transferring to IFR is that you will save a hell of a lot of radio time if you don't have to file an airborne flight plan. It is better to have it in the system before you leave. (You can fax it to Heathrow or similar and then call them to check it is in before you take off).

The issue, in the weather conditions described, is to get a radar service as soon as you can after departure whether it be RAS or RIS. If you are leaving from an airfield that is not within range of a suitable station then you have to take the chance whether you are VFR or IFR

[bookworm]

Whether you deem yourself to be IFR or VFR before receiving your clearance into controlled airspace is a decision you take based primarily on the prevailing weather conditions.

The latest Occurence Reports mentioned an incident in the Scottish TMA where an aircraft had got airborne from an uncontrolled airport with an IFR flight plan and entered class E airspace without a clearance. IIRC the weather was VMC -- I'm not certain if the aircraft entered class D as well, which would change things substantially.

Interesting situation. Is it OK to simply "maintain VFR" in class E until you get a clearance, even though ATC knows of your intention to be IFR? What's standard practice in the US? Do you file a VFR/IFR flight plan for that, or just file IFR?

(Of course it's irrelevant to most of what we do down south in the absence of class E.)

[2Donkeys]

The US position is somewhat different in that at uncontrolled fields, it is usual to call the center on the phone to receive a clearance (with a clearance void time) prior to departure. In this way the situation doesn't occur.

In the case where this is not possible, IFR flights (on IFR Flight plans) must remain outside controlled airspace unless cleared. In the case of class E though, once two way contact has been achieved (defined as an exchange of callsigns) entry is permitted without a specific IFR clearance. VFR flights require no particular formality to enter class E.

If you are filed on an IFR flightplan, and elect to enter Class E claiming to be VFR, this will cause confusion and potential embarassment...

2D

[alphaalpha]

Despite being a PPRuNer for a good while, I still haven't learned how to quote properly. So forgive my home made version please.

2 Donkeys said:
"Where the field is a farm strip, you could telephone for some sort of clearance, but it is more common to take-off and use either London Information or a local LARS/Radar unit to negotiate your entry into controlled airspace."


This depends very much on which part of the country you fly from and which controlled airspace you want to enter.

I fly from Bourn, Cambs. There is generally no problem in entering the local Class D (Stansted or Luton) on an airborne flightplan. The problem comes in trying to get into the TMA.

The difficulty (as I understand it) is that, even having filed and activated an IFR flight plan, the TMA controllers will not have a flight progress strip come out of their computer for the flight and will be therefore unwilling to accept the flight. The Luton and Essex controllers rarely have the time to solve this little problem for you. (Bourn is about 7 miniutes from Class D and about 8-10 minutes from the usual Class A entry points). This time is not enough to call London Info to request and obtain a clearance without orbiting outside CAS for an uncertain time.

So, what about telephoning before take off? For one flight, as luck would have it with a TMA controller sitting in the right seat, he tried to get the flight progress strip out of the system and onto the Essex or Luton controllers' position by phone before we departed. He succeeded, but it took him two or three calls over about 15-20 minutes and I think his success was more due his intimate knowledge of the system and who to talk to than anything else. In other words, not a method open to the average pilot. Even then, the Luton controller was not expecting us.

That leaves the third alternative, telephoning a local ATC unit (not the uncontrolled departure field) before take off and asking them to prepare the ground for you, so you can get the clearance soon after becoming airborne. I don't believe you have any right to such a service and you are relying on their good offices and other workload and priorities not interfering.

I would say it's an unsatisfactory situation for all concerned, pilot and controllers.

AA.

[2Donkeys]

The Luton and Essex controllers rarely have the time to solve this little problem for you. (Bourn is about 7 miniutes from Class D and about 8-10 minutes from the usual Class A entry points). This time is not enough to call London Info to request and obtain a clearance without orbiting outside CAS for an uncertain time.

I think that is the nub of the issue. My examples above made the assumption that the intention was to depart IFR into the airways system, because simply getting an IFR clearance into class D is not a particularly onerous task.

The workload associated with negotiating your own clearance is not trivial and can involve you flying, if not orbitting outside controlled airspace for some time. This makes the UK somewhat unique in requiring IFR pilots to carry VFR charts with them - just in case. UK-based pilots may cope with this adequately. There are many horror stories of foreign pilots struggling badly when their "clearance" contains the line "remain outside controlled airspace". Hard in a C182, very hard in a Citation.

It is a pity that the airspace is too busy and too "uniquely" designed to permit the widespread use of US-style "void after" telephone IFR clearances.


2D

[DFC]

Being told "Remain Outside Controlled Airspace" is not a clearance. I fact it is reinforcing the fact that a clearance has not been issued and one must not enter controlled airspace.

On the Class E issue, Once can enter under VFR without clearance and must remain VMC at all times. If IFR then one can not enter without clearance. So, if departing into or towards class E, if one decides to depart VFR and pick up IFR enroute, one must remain VMC until ATC issue the IFR clearance.

That is diffeent from the Class G case which started this all off...where in the case of say the London TMA, one can continue IFR remaining outside controlled airspace until such time as a clearance is issued.

One point to remember with regard to the London TMA is that if one decides to continue enroute below the base awaiting IFR climb, this can in some cases complicate matters because the flight while not in receipt of a clearance will be moving from sector to sector thus slightly complicating the coordination process. Thus it can at times be easier if the flight holds while awaiting clearance...although this varies from situation to situation and from day to day.

However, what must be remembered is that for an IFR flight intending to enter controlled airspace, a SLOT may be issued by CFMU.

Going back to the flight departing and remaining in Class G, as W Collins correctly says, one can be IFR for a number of reasons and provided that one complies with the minimum height rule in descent towards the destination can be FIR from farm strip to farm strip non-radio.

I also agree that possible with the exception of some choke points below the London TMA, one is more likely to have an airprox in VMC than in IMC.

However, the rules require that except for a local flight the combination of forecast and actual weather must show that the flight or portion of flight can be completed in VMC if the flight departs VFR. If the end of the VFR segment is dependent on receipt of a radar service which is not guaranteed, where is the end of the VFR segment?

There would have to be some point where the pilot would say...if I don't have a radar service by XXX, I'll turn back.........however, given the conditions, is a safe VFR return guaranteed?

One can depart IFR from any aerodrome. Remember however that the relevant part of JAR-OPS applies to all flights and sets the weather minima!!

On flight planning...don't forget the Z and Y flight rules!!

Regards,

DFC

[2Donkeys]

Good summary DFC. Which question were you answering though?

2D

[Timothy]

DFCI also agree that possible with the exception of some choke points below the London TMA, one is more likely to have an airprox in VMC than in IMC.Of course, one reason that fewer airproxes are reported in IMC must be that we may be totally unaware of them :O

Which is why I think that it is more helpful to talk in terms of collisions than airproxes. As Vintage ATCO (I think it was he) said a couple of days ago "a miss is as good as three miles!"

I wonder though, whether the choke points are any more dangerous in IMC than VMC.

I fly between OCK and BIG in VMC on weekends from time to time and it's horrific. Sometimes there seems to be more metal than air.

I don't know if, in the early days, it was easier to see other aircraft than now, but in the present mixed traffic environment in the Epsom area, with 250kt bizjets, 180kt twins, 120kt singles, 100kt rotaries, 80kt singles and 40kt microlights the chances of seeing other aircraft seems to be small. I often fly with two or three other pilots and we all miss seeing something until it zooms past.

What I rely on, and believe to be true, is that the number of people who are flying in Class G and who would choose to be in IMC is considerably less than those who would choose VMC, or not fly at all if VMC is marginal or unavailable, which is why I am happiest in the choke points in IMC rather than VMC. However, I take the precaution of not flying at an exact multiple of 100s of feet (2250 would be typical in the Epsom/Dorking/Guildford area) and I avoid passing through beacons, preferably by a couple of miles.

Will

[IO540]

2D

My examples above made the assumption that the intention was to depart IFR into the airways system

In which case, surely, one needs to file an IFR flight plan, via Brussells, 3 hours before the flight.

[2Donkeys]

In which case, surely, one needs to file an IFR flight plan, via Brussells, 3 hours before the flight.

It is true that in order to fly an IFR flight in controlled airspace, Brussels needs to get a flight plan. 3 hours is a little extreme, and most flight plans can be turned around inside an hour if you have take the trouble to pre-validate the route.

However, if you are implying that having a flight plan in the system will in some way ease your clearance into controlled airspace, this is only partially true. There is a considerable gap between filing a flight plan, and finally receiving a squawk, frequency and clearance to blast into controlled airspace. Your flightplan will not necessarily be sent to every conceivable class D provider that you might wish to use to organise you clearance, and therefore you will be treated with caution if you call xyz Approach up unannounced looking for asssitance. This is precisely the point that AlphaAlpha makes.

As a result, the normaly way of getting your clearance, having departed from an uncontrolled field, is to call London Information telling them your registration, position, time of departure and requirements, and they will activate your flightplan and liase with an appropriate ATC unit to arrange your clearance. In due course, they will relay a squawk and frequency and hand you to your airways controller (or as appropriate).

2D

[bookworm]

It is true that in order to fly an IFR flight in controlled airspace, Brussels needs to get a flight plan. 3 hours is a little extreme, and most flight plans can be turned around inside an hour if you have take the trouble to pre-validate the route.

Slots are issued 2 hours before EOBT for flights in the system already on a first-come-first-served basis. While there's no doubt that many if not most FPLs can be turned round quite quickly, there's a tactical advantage in getting the FPL in by then if things are going to get busy.

[2Donkeys]

if things are going to get busy.

Its a bit of a diversion, but with the exception of low viz or thunderstorm activity within the TMA, it is pretty unusual for things to get sufficiently busy for a serious slot delay to be incurred at typical light GA levels.

I have suffered more slot delays since flying heavier higher stuff than I ever have flying unpressurised piston.

Of course, attempting to fly through the Clacton sector at 1600 on a Friday afternoon is asking for trouble

:O

2D

[alphaalpha]

Further to the discussion on difficulty of obtaining a clearance into the LTMA when departing IFR from an uncontrolled airfield:

Has anybody tried including in the flightplan address list, the unit which will be initially contacted?

For example, in my scenario above, flying from Bourn south into the LTMA via BKY, including Essex radar in the address list. If so, including an estimate for BKY in the RMKs might also help?


Entirely subjectively, I agree with WCollins in that I too feel happier in IMC, compared to low-level VMC, whether in marginal or good visibility. The low traffic density and big-sky theory do provide separation comfort.

Under circumstances where you are flying at WCollins 2250 feet and there may be VFR traffic below a 1500 foot cloudbase, the availability of a radar service does not help much. Under RIS, a fair proportion of the contacts called will not be squawking, or not squawking mode C, hence you have to trust that they are actually VFR and below cloud, so separated from you. At least this is my mind-set inthese circumstances. The benefits of RAS here are questionable -- you would be lucky to make much progress towards your destination.

AA

[IFollowRoads]

However, if you are implying that having a flight plan in the system will in some way ease your clearance into controlled airspace, this is only partially true. There is a considerable gap between filing a flight plan, and finally receiving a squawk, frequency and clearance to blast into controlled airspace. Your flightplan will not necessarily be sent to every conceivable class D provider that you might wish to use to organise you clearance, and therefore you will be treated with caution if you call xyz Approach up unannounced looking for asssitance.

One thing you can try, and seems to have a reasonable amount of success for me, is to add the address of the unit you wish to call first on the addressee part of your flight plan. In most cases, this is the ICAO id suffixed with 'ZTZX', but either the AIP or a phone call will give the definitive answer. (in fact, if calling the ATSU on the 'phone first, they might well tell you who they would like it addressed to)

Just another drop of oil into the vast number of cogs.....

[Timothy]

you are flying at WCollins 2250 feet Hey! Steady on, that's my altitude...you go and find your own :E :p

Will

[alphaalpha]

Can't we share, me north of Heathrow, you to the South -- pleeeze.

AA.