No RIS due too much traffic!

[fireflybob]

Got airborne this pm and called Waddington for a Radar Info Service only to be advised the Flight Info Service only available and no RIS due too much traffic!

Just wondered why this would be - were they short staffed perhaps?

All I wanted to do was have a radar service to get VMC on top. I have been declined RIS for other reasons previously but not too much traffic.

[Chilli Monster]

It's actually a valid reason, even though it seems like a cop out. When you've only got one frequency then by definition only one controller can be working it. If that person feels their workload is such that they cannot fulfil the requirements of a RIS then so be it.

How busy was it?

[Evil J]

Happens quite a lot particularly north of Tollerton, especially near Syerston.

imagine the scene. You call a radar unit and are given a squawk then identified. On the screen there are 15 contacts in the next 5 miles of your flight, how on earth do you call all of those contacts? And even if you do no one else will be able to get in on the frequency for the next 5 mins meaning that I am providing 1 RIS when I could be providing 10 or more FIS'. In the situation described above the best you can really hope for is a generic warning to "keep a very good lookout multiple contacts ahead." That is generally the use of RIS limited due traffic density.

Hope that makes sense - quiz me more Thursaday if you wish!!

[Talkdownman]

The theoretical number of traffic calls required is x (x-1) where x = the number of aircraft affected.

eg. 5 aircraft means (theoretically) 5 x 4 =20 traffic calls.
A sixth one calls and it goes up to 6 x 5 = 30 calls.
Then fireflybob calls and it goes up to 42 calls!

Then full RIS becomes uncontainable so it is downgraded to FIS generic warnings....

.....but then 'Duty of Care' raises its ugly head :{

TDM

[Final 3 Greens]

Talkdownman

Sorry, your formula is wrongly applied.

This formula is used to calculate the complexity of inter group lines of communication, not communications between one person and five others - unless you normally allow your traffic to talk to each other with regularity ;)

In reality, the length of call will be more the determining factor. as EvilJ has pointed out.

[Aussie Andy]

It is very common not to be able to get RIS when required from many LARS units because a) they get busy and b) equipment doesn't always work.

For example, climbing through cloud during IMC lesson on Saturday morning between Henley and Woodley when I called and asked for RIS they initially said "yes" but after identifying me on SSR, said that due to equipment problems they had poor primary radar coverage in my area so RIS not possible and downgraded to FIS. Meanwhile as more people called the frequency they started to turn down even FIS for a little while as they were doing the one-armed paper hangar trick.

Its really not their fault - we have to remember that, right or wrong, the LARS service is not funded sufficiently well to give as more than a "best efforts" service. Would that it were otherwise... but the efforts of the guys in the LARS units is appreciated and I would recommend anyone do as many of us have done and pay them a visit to see what they are up against.

Roll on Private IR (there's a rumour!) so that we can get and choose a proper level of service in an airway when / if required. Today we don't have that choice.

Andy

[Ludwig]

There is something ironic about the contradictory drive to make us all visible, (mode S etc) with there being either too few staff at RIS units, or crap kit that does not work! Flying on Sunday in that no-mans gap between Coventry and Rugby in IMC and Coventry could not give us any radar cover, just FIS - not a lot of use really.

With all the “big jets” going into Coventry through open FIR, this could get really messy. Still, I’m sure the TCAS works just fine.

[tunalic2]

I think i'm right in saying that Coventry only 'mans' its radar at certain times so that service is only available then.
T2

[Windy Militant]

Perhaps someone can clarify a point for me. We had an ATCO from Benson give a talk for a PFA strut years ago who said that the reason that they often can't provide either RIS or RAS cover is the zone of separation required is greater than that required for FIS. Therefore in a given block of air space only a certain number of RIS or RAS movements can be handled. FIS allows more movements through the same area. Am I right in thinking that FIS applies VFR separation rules whilst RIS and RAS use IFR separations?

[robin]

My understanding is that FIS does not provide separations at all

[Chilli Monster]

the reason that they often can't provide either RIS or RAS cover is the zone of separation required is greater than that required for FIS.

What utter b:mad:ks

Separation has nothing to do with type of service required - purely as to whether the aircraft are VFR or IFR.

The only caveat with this is with RAS only, whereby you either get 3nm (horizontal) / 1000ft (vertical) separation between traffic known and being worked by you, which increases to 5nm / 1000ft if the aircraft is known to be working an adjacent agency and the mode 'C' data has been verified. If it's not known to you then it's 5nm / 3000 ft. That's why it's only available to IFR traffic.

If you have an IFR on a RIS you separate it from other IFR's and pass traffic on VFR's. If you have two VFR's on RIS you pass traffic information and that's it - you don't separate them.

[Whipping Boy's SATCO]

Windy, you're either having a laugh or your airmanship is somewhere around that of the lowest common denominator.

RAS and RIS are services that are mutually agreed between pilots and controllers. These services are only applied if both parties can comply with the terms of the agreement. From a controller's persective, if he/she cannot provide an effective service then they will refuse to apply the service; there's nothing to be gained from 'leading the pilot up the garden path'. This is a decision made at the time, depending upon the general air traffic situation.

Talkdownman, are you really a controller?

[Evil J]

And further to all that, under FIS, RIS and RAS the pilot is still ultimately responsible for ensuring separation from other aircraft.

Ludwig,

Going up the LIC gap give us at EMA a call, we're not a LARS unit but subject to loading we are usually happy to provide ATSOCA's (although that can depend who's on the desk at the time!!!!!!!!!)

[fireflybob]

Thanks for all the comprehensive replies!

I get the impression that some pilots think they might be in receipt of some sort of radar service when they are given a squawk for a FIS - as Evil J quite correctly states it is the pilot who is ultimately responsible for separation and perhaps it is timely to note that the legislation states that lookout must be maintained whether or not the aircraft is in receipt of an ATC service.

Finally, I am somewhat surprised, nay disappointed, that a minority of pilots seem happy to fly in cloud without any form of radar service - I suggest this is an airborne form of Russian Roulette.

[Chilli Monster]

Finally, I am somewhat surprised, nay disappointed, that a minority of pilots seem happy to fly in cloud without any form of radar service
Happy - no, but in some parts of the country there are times when you have no option :(

Also I'm going to disagree that the pilot is ultimately responsible for his own separation under a RAS.

MATS pt 1 Section 1 chapter 5 para 1.4.1

c) There is no legal requirement for a pilot flying outside controlled airspace to comply with instructions because of the advisory nature of the service. However, should a pilot choose not to comply with advisory avoiding action then he will become responsible for his own separation and any avoiding action that may subsequently prove necessary.
Now - that reads to me that until he disregards an instruction given under RAS it's the controllers responsibility to separate the aircraft - once an instruction is disregarded the pilot is effectively under RIS where it is their responsibility to provide their own separation.

[Halfbaked_Boy]

Yup, on our way back up from LFAT Luton wouldn't give us a RAS through zero vis... that was understandable however, what with all the 'easy traffic' around :p

[Windy Militant]

I obviously didn't phrase that very well. Still I got the clarification I wanted even if it made my ears burn.

[fireflybob]

Chilli Monster, thank you for your robust technical correction re RAS.

>Happy - no, but in some parts of the country there are times when you have no option <

Well I beg to differ but actually you do have an option - you either remain clear of cloud or do not go flying! That may be easy to say when there is a task to do but nevertheless it is AN option.

[fireflybob]

Another aspect local to Syerston/Tollerton is that I believe the motor gliders which operate from Syerston do not have Mode Charlie.

When one is instructing/general handling from Tollerton one usually goes North and East to keep clear of the EMA airspace. This tends to put one in conflict with the motor gliders from Syerston during climb and descent and, I presume, the lack of Mode C may increase controller workload?

Of course any form of control service in the open FIR (what I call "jungle airspace") is an anethma to certain airspace users and indeed whilst instructing VFR I don't particularly want any service (that includes FIS by the way) since extraneous RT chat can be a distraction to the exercise. This does not mean one is not prudent about where one conducts certain exercises or that one never listens out but if there is a thin layer of cloud and you want to operate VMC on top then I am only happy to climb through if I have some sort of radar service.

Sorry to stray a bit off topic but I think this is relevant to the debate.

[Pie Man]

the lack of Mode C may increase controller workload

ffb - it does increase workload as we may be calling traffic that is not relevant. I have of late taken to asking pilots I'm providing a sevice to if they have mode C - you would be suprised how many have diliberately not switched it on.

As you rightly mention those who think they are getting a radar serivce because traffic information has been passed (under 'duty of care') are the problem. If we could give a true FIS and not have to keep an eye on the traffic to advise about conflictions we would have more time to provide RIS and RAS.

PM

[Evil J]

Chilli,

I agree, but what about that aircraft that doesn't show on radar? How, under a RAS do you provide separation from that?

the ANO refers, section IV, 17 1 (a)

"Notwithstanding that the flight is being made with air traffic control clearance it shall remain the duty of the commander of an aircraft to take all possible measures to ensure that his aircraft does not collide with nay other aircraft."

[Chilli Monster]

I think we're getting into semantics here, but to play the game further:

1) You can't avoid traffic you can't see, whether as an ATCO on radar or as a pilot. There's nothing you can do about it - it's just a fact of life. Those of us who do most of our work outside CAS have to come to terms with this and do the job as best we can.

2) How does an aircraft in cloud take all possible steps to avoid collisions - easy:

a) Flies in accordance with the IFR's; and;

b) (most relevant to this argument) He gets a RAS or RIS from an appropriate ATC unit (if available), and in the case of the RAS he is relying on them to provide the separation - in effect, he has transferred that responsibility.

If you refer to MATS pt 1 it's even accepted that there are possibilities (unseens or pop-ups) whereby standard separation may not be achieved. You just do the best you can and then wait for your licence to be suspended when the TCAS RA goes off :rolleyes:

Want to swap jobs? ;)

[ShyTorque]

It IS a fact that aircraft are obliged to fly in cloud without a radar service, it happens quite often. I'm not happy with the situation when it occurs and will try to change level to gain some sort of in flight visibility if at all practical. Sometimes it's not (icing conditions or airspace above, or terrain below. TCAS is of some help but not by any means the full answer, as indeed a radar service isn't the full answer in class G.

I always try to tell folks how valuable Mode C is. If fitted, use it please - TCAS means I can avoid you and we are all safer.

As far as staying on the ground if it's cloudy? I wish!

[fireflybob]

the ANO refers, section IV, 17 1 (a)

"Notwithstanding that the flight is being made with air traffic control clearance it shall remain the duty of the commander of an aircraft to take all possible measures to ensure that his aircraft does not collide with any other aircraft."....

and perhaps it could be argued that if the commander is unable to receive some sort of control service (radar, procedural in CAS) whilst flying in cloud then "all possible measures" includes taking another route, altitude/Flight Level or even not embarking on the flight!

ShyTorque, I know exactly where you are coming from since I have often been there myself and when you are flying for a living we have to make a professional "risk assessment" of the situation at the time....but once the action of flying in cloud without any radar cover becomes a president then I think we all need to take a rain check as to what it's all about.

I am NOT saying I would NEVER fly in cloud without radar but when it becomes a regular habit then we are stacking up the odds for something rather unpleasant! Also, in the litigous type of world we know seem to live in it's giving the lawyers plenty of ammunition should anything go wrong.

[ShyTorque]

Not an ideal world, there's not enough LARS units these days but I didn't say I do it routinely or without awareness of the situation! We carry TCAS for this reason.

However it's not practical to avoid flying because for example, Pennine Radar has been withdrawn (see recent NOTAMS) or to divert because Leeds Bradford can't offer a Zone transit or are too busy to offer Radar Information Service as you go around the edge of their airspace.

If we refused to fly because it was cloudy then we would be out of a job by lunchtime.

p.s. blame your father, I think he helped teach me ;)

[bookworm]

and perhaps it could be argued that if the commander is unable to receive some sort of control service (radar, procedural in CAS) whilst flying in cloud then "all possible measures" includes taking another route, altitude/Flight Level or even not embarking on the flight!

Surely that's much more appropriate to a "fine" summer's day than flying in cloud? The probablility of collision is dominated by traffic density: the risk is much higher on a VMC day with high traffic density than in cloud with much lower traffic density -- in fact I'm aware of no collisions in cloud in the UK at all.

[Evil J]

Its a big sky after all!!!

Shame that in this day and age of high technology, aircraft that can land themselves etc etc, people still have to resort to the big sky theory when flying IMC outside CAS!!

[fireflybob]

>Surely that's much more appropriate to a "fine" summer's day than flying in cloud? The probablility of collision is dominated by traffic density: the risk is much higher on a VMC day with high traffic density than in cloud with much lower traffic density -- in fact I'm aware of no collisions in cloud in the UK at all.<

I wonder how many AirProxes have occured in cloud without either pilot being aware of getting close to another aircraft. Twice in my flying career I have heard the engines of another aircraft whilst flying in cloud!

At least when you are flying VMC (or not in cloud, say) you have a fighting chance of seeing another aircraft and avoiding it and generally the traffic density is higher now than it used to be even when flying IMC.

Just because we cannot recall a collision in cloud does not mean that it cannot occur.

Oh and by the way, Shy Torque, my father taught me too and he taught me never to go into cloud without radar!!

[ShyTorque]

Then best you stay out of cloud without radar, old chap. :ok: