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When is a RIS not a RIS?

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When is a RIS not a RIS?

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Old 8th Sep 2001, 20:42
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Question When is a RIS not a RIS?

Does anyone else find the phrases "Duty of care" (SRG) and "Best practice" (RAF STC) making the waters surrounding provision of RIS extremely muddy? In recent months I've heard both used in relation to controllers providing separation under RIS. Separation under RIS!!? "....however vectors shall not be provided to maintain separation from other aircraft, which remains the responsibility of the Pilot...." Surely, when a pilot requests a RIS he must be aware of the contract he is making, principally the fact he is responsible for his own separation. Of course, he can ask for vectors or RAS, but in the present climate it seems that if we feel the need to up-date the position of conflicting traffic (RIS para b) we should also be offering some form of avoiding action whether asked for or not. It would seem that either the current conditions for provision of RIS are in urgent need of review or,alternatively, pilots should be made fully aware of the controllers obligations, putting some of the responsibility back with them where, at the moment, it apparently officially belongs!
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Old 8th Sep 2001, 21:12
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Lot's of questions, not many answers. My personal view is that the water is indeed somewhat muddier than a few years ago. What is obvious is that controllers are becoming more rule-bound and, on refering to regulations, they find them to be rather convoluted; JSP318A definition of RIS is most definitely "wide-ranging and comprehensive". Furthermore, look at the latest defn of FIS and you will give yourself a fright about the provision of traffic information.

Maybe it is time to go back to basics and consider VFR, IFR, VMC and IMC rather than concentrating on RIS, RAS, FIS etc. How many aircrew (including non-UK) understand our system?

[Edited because my first attempt was a little 'bold'.]

[ 08 September 2001: Message edited by: Whipping Boy's SATCO ]
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Old 10th Sep 2001, 00:54
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"however vectors shall not be provided to maintain separation from other aircraft, which remains the responsibility of the Pilot..."
Yeah, right...try telling that to the Judge & Jury when two aircraft receiving a RIS from you have collided & the SRG Lawyer is quoting "duty of care" !
Has anyone seen anything in writing saying what it actually means ? IMHO if they have to use the phrase, it means they know the rules are inadequate but no-one is prepared to change them.
"recommended spacing for wake vortex" is another cop-out which comes to mind ......
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Old 10th Sep 2001, 01:24
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We had a discussion about this just the other day. Yes, the definition is definite, but the "hints" from other official sources are getting daft. If the pilot enters into a contract with us, he should hold up his end, and know what he's getting. Of course, no-one would sit and watch them merge with something else, but what happens when after calling the traffic a few times and getting "roger", when you eventually take fright and give avoiding action, turning that non-IMC-rated PPL straight into a nice wadge of cloud (imposing an unasked-for RAS on someone unqualified to use it) from whence he span into the ground.
Or even worse, he could see your traffic but hadn't mentioned it, took your turn anyway and whacked into an aircraft neither of you saw. Two for one, anybody? Try explaining either of those at the BOI.

It seems to me that if we go by the book we get shafted, and if we go by the "advice" we are screwed.

IMHO, the skies are very dangerous anyway, so under "duty of care" my "best practice" has to be to keep the nutters on the ground in the first place. Maybe they should go by train. That would be safer, wouldn't it....?
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Old 10th Sep 2001, 02:09
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I cannot understand why there has not been an enormous outcry from unions and GATCO on this subject. The way in which the SI about duty of care was just published with no consultation was quite disgraceful. It seems to be saying that the verbal contract agreed between pilot and controller to accept/provide a RIS - with all the limitations that such a service implies - is quite worthless and that the controller had better be prepared, in effect, to provide a RAS. on demand, at any time.
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Old 10th Sep 2001, 17:37
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Here's a pilot's perspective, which may or may not be helpful!

I'd rather have a best-effort service than no service at all. 'Duty of care' scares me, because it scares you ATCOs.

There has always been an unacceptable gap between RIS and RAS, and recent developments haven't helped. The situation in theory is simple: controller passes information -- pilot takes appropriate action. In practice, it doesn't work like that, because the information passed is insufficient.

A typical RIS traffic advisory would be "G-ABCD, traffic 1 o'clock, 4 miles, crossing right to left, no height information."

Contrary to the opinion you will often hear among pilots that lookout is easy, converging aircraft are remarkably difficult to see. They don't have any relative motion. It's highly unlikely that you will spot another light aircraft at 4 miles, even with a clock-sector to search. At four miles, the conflicting aircraft typically subtends 0.05 degrees by 0.02 degrees. That's the same size as a 0.5 mm by 0.2 mm spot on the windscreen. It may be at any level, and is as likely as not obscured by clutter. So the controller gets a "Roger" or "Looking" in response. At typical GA closing speeds, we're now about 60 seconds away from shards of metal raining down.

What the pilot really needs to know, and what standard traffic information doesn't tell, is where it looks like the conflicting aircraft will pass relative to his own aircraft, and how close.

The relative passing position (will it go down his left side or his right side) should help the pilot to start manoeuvring to increase the separation before he spots the conflicting aircraft. If he leaves the turn until he finally spots it, it may be too late.

The proximity should determine the urgency of the pilot's search. Sure, it's nice to know if traffic looks to be passing a mile and a half down the port side. If he's lucky, he may just see it as he goes by. But even though that's not standard separation, it's not unusual for light aircraft passing each other. If he spends his time seraching for every aircraft that comes within 5 miles, in busy areas he will never stop searching, his workload will become unsupportable, and he may not see what he needs to see ahead.

Of course in both of these aspects, the accuracy of the radar is an issue. But even getting a best guess from the radar is better than nothing at all.

Under a RAS the case moves towards the opposite extreme. The controller passes the pilot avoidance information in good time, usually well before the pilot has a sensible chance of sighting the other aircraft. Thus the pilot is left with a choice of taking an extensive vector around a popup that is extremely unlikely to pose a threat, and rejecting the avoidance advice before he has sighted the conflicting aircraft (or perhaps ship, truck or shower). The pilot may be reluctant to do this, and the resulting chain of vectors around popup/slow-moving/no-height-information traffic gets stressful for both pilot, who's losing situational awareness, and controller who's trying to reach the separation target in changing circumstances, often with constraints on the airspace that can be used. This seems pretty typical of a day with, say, BKN018, where an IFR aircraft is in, or in and out of, the clouds at 3000 ft or so, with assorted VFR stuff operating below the base.

If the pilot were looking at the radar display, he would make a judgement as to:

a) the risk level of the threat (which may depend on a number of factors not apparent to the controller)

b) the manoeuvre apparently required to increase separation

c) the separation to be expected at closest approach

d) the rate at which updates are required if the conflicting aircraft is not sighted

In principle, it's not much different from walking down a high-street pavement avoiding collisions. Try doing that with a blindfold and an observer saying "if not sighted..."

I think the Duty of Care issue makes it less likely that the controller will pass useful information to the pilot. Anybody prepared to say "it appears as if it will pass half a mile down your right hand side" these days? Or "probably a low level contact, possibly a glider"? Or "turning right looks a little better than turning left"? You're brave if you do.

The solution. The only one I can think of is bringing the picture into the cockpit with some sort of Cockpit Display of Traffic Information. Then the pilot can get close to making those judgements for himself. Until then? Who knows?
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Old 10th Sep 2001, 17:52
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Here's a pilot's perspective, which may or may not be helpful!

I'd rather have a best-effort service than no service at all. 'Duty of care' scares me, because it scares you ATCOs.

There has always been an unacceptable gap between RIS and RAS, and recent developments haven't helped. The situation in theory is simple: controller passes information -- pilot takes appropriate action. In practice, it doesn't work like that, because the information passed is insufficient.

A typical RIS traffic advisory would be "G-ABCD, traffic 1 o'clock, 4 miles, crossing right to left, no height information."

Contrary to the opinion you will often hear among pilots that lookout is easy, converging aircraft are remarkably difficult to see. They don't have any relative motion. It's highly unlikely that you will spot another light aircraft at 4 miles, even with a clock-sector to search. At four miles, the conflicting aircraft typically subtends 0.05 degrees by 0.02 degrees. That's the same size as a 0.5 mm by 0.2 mm spot on the windscreen. It may be at any level, and is as likely as not obscured by clutter. So the controller gets a "Roger" or "Looking" in response. At typical GA closing speeds, we're now about 60 seconds away from shards of metal raining down.

What the pilot really needs to know, and what standard traffic information doesn't tell, is where it looks like the conflicting aircraft will pass relative to his own aircraft, and how close.

The relative passing position (will it go down his left side or his right side) should help the pilot to start manoeuvring to increase the separation before he spots the conflicting aircraft. If he leaves the turn until he finally spots it, it may be too late.

The proximity should determine the urgency of the pilot's search. Sure, it's nice to know if traffic looks to be passing a mile and a half down the port side. If he's lucky, he may just see it as he goes by. But even though that's not standard separation, it's not unusual for light aircraft passing each other. If he spends his time seraching for every aircraft that comes within 5 miles, in busy areas he will never stop searching, his workload will become unsupportable, and he may not see what he needs to see ahead.

Of course in both of these aspects, the accuracy of the radar is an issue. But even getting a best guess from the radar is better than nothing at all.

Under a RAS the case moves towards the opposite extreme. The controller passes the pilot avoidance information in good time, usually well before the pilot has a sensible chance of sighting the other aircraft. Thus the pilot is left with a choice of taking an extensive vector around a popup that is extremely unlikely to pose a threat, and rejecting the avoidance advice before he has sighted the conflicting aircraft (or perhaps ship, truck or shower). The pilot may be reluctant to do this, and the resulting chain of vectors around popup/slow-moving/no-height-information traffic gets stressful for both pilot, who's losing situational awareness, and controller who's trying to reach the separation target in changing circumstances, often with constraints on the airspace that can be used. This seems pretty typical of a day with, say, BKN018, where an IFR aircraft is in, or in and out of, the clouds at 3000 ft or so, with assorted VFR stuff operating below the base.

If the pilot were looking at the radar display, he would make a judgement as to:

a) the risk level of the threat (which may depend on a number of factors not apparent to the controller)

b) the manoeuvre apparently required to increase separation

c) the separation to be expected at closest approach

d) the rate at which updates are required if the conflicting aircraft is not sighted

In principle, it's not much different from walking down a high-street pavement avoiding collisions. Try doing that with a blindfold and an observer saying "if not sighted..."

I think the Duty of Care issue makes it less likely that the controller will pass useful information to the pilot. Anybody prepared to say "it appears as if it will pass half a mile down your right hand side" these days? Or "probably a low level contact, possibly a glider"? Or "turning right looks a little better than turning left"? You're brave if you do.

The solution. The only one I can think of is bringing the picture into the cockpit with some sort of Cockpit Display of Traffic Information. Then the pilot can get close to making those judgements for himself. Until then? Who knows?
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Old 10th Sep 2001, 18:52
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When I'm giving a RIS and a collision looks imminent , I'm required by English Common Law to do something whether under the guise of Duty of Care or not. I can't ignore an immiment danger.

If time , I'd normally suggest a heading if the traffic were not sighted but in the worst case I'd make sure that my traffic was moving its wings to create a better visual profile.

This method seems to work in the Vale of York!

[ 10 September 2001: Message edited by: hatsoff ]
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Old 11th Sep 2001, 12:51
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I usually prefer getting a RIS to a RAS, mainly for the points made by bookworm in his excellent posting.

There are frequent occasions on which I can see very clearly that there is no conflict with traffic. However, if I am in any doubt, I can always request vectors or an upgrade to a RAS.

Having a RAS and getting vectored around every slow-moving dot ("no height information") that pops up on your screen can often negate any advantage you gain by going outside controlled airspace (assuming there's an airway alternative).

Don't get me wrong - I'm not ungrateful for all the effort ATC put in, particularly down the Vale of York and the rest of the East Coast, by Newcastle, Pennine and London Mil. I appreciate it's a stressful job for you guys and gals, and generally there's good teamwork in keeping two lumps of metal from going BANG.

The problem lies in the system, in the (lack of) control of military traffic, in liaison between, for example, Buchan and you guys, or the E3 and you, in lack of a sensible airway system...

Anyone going to the BALPA/GATCO bash next month?

I shall be holding forth on this very subject there.
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Old 11th Sep 2001, 16:21
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Whikst on the subject of RIS/RAS/FIS differences, just how many of the pilots know the difference between, IMC,VFR,VMC,IFR? It astounds me how often you can ask a question regarding flight rules or flight conditions and get the wrong response.
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