Cambridge "Airspace"

[FREDAcheck]

I think some people get overly concerned about ATS units issuing instructions to aircraft in Class G airspace. It's clear in several places in CAP493 that they're entitled to do so. This is not linked to specific text about "overflying aircraft place themselves under the control of...".

As Jim59 points out, it says in Section 3, Chapter 1 Table 1:

Instructions issued by controllers to pilots operating outside controlled airspace are not mandatory; however, the services rely upon pilot compliance with the specified terms and conditions so as to promote a safer operating environment for all airspace users.

and in the same chapter, Section 1B.2:

Although IFR/VFR flight within Class F/G airspace outside the ATZ is permitted without an ATC clearance, controllers will act on the basis that pilots will comply fully with their instructions in order to promote a safer operating environment for all airspace users.

Which would you rather: get into an I-know-my-rights debate with a controller, or avoid a potential unsafe situation that the controller knows about and you may not?

Or better still, ignore the controller (as you know your rights) and get into a situation such as JW411 described?

If you don't like the instruction (as you know your rights) I suggest "Unable to comply..." might be a possible response (and hope the controller can sort out any conflict). I don't think "I am able to comply but I know my rights and I'm not going to" is in CAP 413.

Edit: I'm not suggesting for a moment that JW411 or the other aircraft were ignoring ATC instructions!

[JW411]

Thank you for that.

The whole gist of this thread reminds me of something the man who got me into aviation in the first palace back in the 1950s used to say:

"I don't mind dying but I would hate to lose my licence".

[150 Driver]

I fly regularly near and into Cambridge, I've never found the controllers anything other than helpful.

Mind you, my approach is that if I'm told to do something I do it as there must a good (i.e. safety) reason for them to ask me. Being within my rights but dead isn't clever.

It's worth pointing out that in the uproar here on the Southend airspace grab that some were posting that they never bothered speaking to Southend as (to paraphrase) they didn't like them.

So, if we don't want a Cambridge airspace grab, it must be in our interests to communicate and work with them ?

[Johnm]

The whole point of having ATC or AFIS is to promote a known traffic environment so co-operating with a controller or FISO makes you part of that known environment. What's not to like?

[tmmorris]

I'm with the last two posters on this. Flying from a military airfield I know that pilots don't have to communicate to cross the MATZ, and that ATC behave as though it's CAS; but it's still idiotic not to speak to ATC in such a busy environment.

[abgd]

What's to not like, is that if they take it for granted that you'll do what you're told, then it might as well be controlled airspace. There's enough overt airspace grabbing without co-operating/enabling a covert airspace grab.

In practice I can't see myself refusing a reasonable request that's likely to improve my safety and that of someone else. But I think it's reasonable to expect it to be phrased as a request rather than an order.

Secondly, at least when overt airspace grabs are granted, you know where the pinch points are. If controllers take to manipulating class G traffic in an opaque and haphazard manner, it's 1) going to make flight planning more difficult and 2) could conceivably lead to unanticipated pinch points or other airspace issues that aren't subject to any scrutiny.

[FREDAcheck]

What's to not like, is that if they take it for granted that you'll do what you're told, then it might as well be controlled airspace. There's enough overt airspace grabbing without co-operating/enabling a covert airspace grab.

Which would you rather: co-operate voluntarily with ATC in Class G, or get Class D imposed on you so you have to do what you're told?

Places like Norwich have very little commercial traffic, but were getting people doing aeros for 20 minutes on the approach not talking to anyone, leaving KLM flights holding over the N Sea.

[abgd]

Which would you rather: co-operate voluntarily with ATC in Class G, or get Class D imposed on you so you have to do what you're told?

Read what I said: "In practice I can't see myself refusing a reasonable request that's likely to improve my safety and that of someone else. But I think it's reasonable to expect it to be phrased as a request rather than an order."

If compliance is voluntary, I would expect the language used to reflect this. Not least because a pilot is more likely to decline to do something silly, if requested rather than ordered.

VFR flying is generally lower than IFR flight. Terrain and cloud avoidance takes up more of our attention. A VFR pilot should be constantly thinking about forced landing areas, the glide-clear rule and where the Red-Arrows happen to be flying today. Navigating a legal and safe path through UK airspace can be a real challenge, without changes to your flight plan being made at the whim of a controller.

If I were an ATC I would be wary about telling VFR pilots in class G what to do.

[FREDAcheck]

If compliance is voluntary, I would expect the language used to reflect this.

I did read what you said, but it's not efficient to negotiate every time whether the pilot is happy to co-operate.

The present system is fine IMHO. ATC gives you and instruction. If you don't want to co-operate, you say so. As most pilots (you included, you say) will normally be happy to comply, then this is the sensible default. For those that aren't, or for those circumstances where it's not safe to comply, then they can say so.

It's a matter of efficient operation of airspace, not a matter of avoiding upsetting those that Know Their Rights.

Or can you suggest a better form of words that is ICAO compliant and doesn't waste valuable airtime? If so, write to the CAA and suggest a change to CAP 413.

[abgd]

Won't 'REQUEST' and 'WILCO' or a standard acknowledgement cover most situations? They're already in CAP 413.

[FREDAcheck]

Yes, that would work.

If ATC say "Request" then I would think they've got to wait for the pilot to confirm whether or not they're going to do it. I would have thought giving an instruction and presuming compliance unless the pilot says otherwise is more efficient. However, the important thing is that everyone agrees the basis of the communication.

As I say, if you think the present position is not optimum, lobby for a change. Given the conservatism of aviation, and the huge inertia, I wouldn't hold out too much hope!

[abgd]

If ATC say "Request" then I would think they've got to wait for the pilot to confirm whether or not they're going to do it. I would have thought giving an instruction and presuming compliance unless the pilot says otherwise is more efficient.

In controlled airspace I would expect ATC to want me to read back any significant instruction e.g. an altitude or heading change. I don't see why this should be different for an aircraft in uncontrolled airspace. If it's worth communicating about, it's worth communicating about clearly.

As I say, if you think the present position is not optimum...

I haven't been flying for long enough to have a good sense of perspective, but surely the premise of this thread is that ATC are increasingly giving instructions to aircraft outside of controlled airspace. i.e. there's a change in ATC's behaviour. In that case, it's up to ATC to lobby for a change in the status-quo, not me.

[FREDAcheck]

Yes, agreed, it could work.

Good luck trying to change it!

[Talkdownman]

Originally Posted by abgd

ATC are increasingly giving instructions to aircraft outside of controlled airspace. i.e. there's a change in ATC's behaviour. In that case, it's up to ATC to lobby for a change in the status-quo, not me.

Totally concur.

For a start ATC (sic) outside controlled airspace should be re-designated 'Air Traffic Advisory Service'. Perhaps the offending units might then address their delusions.

[ShyTorque]

I will always try to comply with any ATC request, as long as it's reasonable and safe and I hope other pilots will always do the same.

However, in the past I have refrained from speaking to certain ATC units because the previous requests from them were not as above.

For example, on requesting a basic service, being "ordered" to immediately deviate over 90 degrees off track in Class G airspace to "avoid" a commercial aircraft on a parallel track to us some 4nm away and descending to land and already below us. When we advised ATC we could see it and would maintain our own separation from it, the ATCO tersely told us that "well it might go around and climb towards you". If it did, as it was on our left side, we had right of way under the rules of the air. The unit concerned has an ATZ, which we were avoiding by a 3nm margin on our planned track. Next time he didn't get a call.

On another occasion, having tried to obtain a basic service from a radar unit, whilst flying and remainng in Class G, I was told in no uncertain terms to standby, i.e. "Aircraft calling XXXX Radar, STANDBY!"

A long "standby" followed. I latterly tried to say we were going en route but was immediately told again to "STANDBY!". I waited on frequency until we really needed to call the next, far more relevant ATC unit. In the meantime, we had seen an airliner flying outside of CAS, well ahead of us. We had stopped our climb and had turned sufficiently right to pass well behind it to ensure we passed behind and below. Suddenly ATC ordered us to turn immediately right by another 50 degrees. At this stage were were not receiving any form of ATC service and had not been positively identified so the Captain/HP did not make the turn because we couldn't be certain it was intended for us. After all, we were in Class G and remaining so and responsible for our own separation, which we had already taken.

ATCO then began to remonstrate with us for not taking his avoidance turn, in a threatening and belittling tone. I replied saying why not. ATCO then told us that "if that airliner gets a TCAS alert he will file against you!" We also had TCAS and it was no problem, we were both in Class G and it was a definite case of see and avoid, which we did.

I replied that this was not a suitable time to discuss it further and that we would call him by phone on landing which the captain did. The ATCO maintained his angry stance and was adamant that we must in future take his instructions. We maintained that in the circumstances he was incorrect. I urged the captain to MOR it and he chose not to. Next time I certainly would do so.

[PA28181]

Lets be clear about all this, in the UK there are two types of airspace, controlled and un-controlled.

There are ATSU's who provide services to pilots in CAS and outside CAS.

When people try to blur the distinction's by accusing all those who do not agree with being "instructed" to comply with ATC "requirements outside of CAS they are immediately and condescendingly labeled as the "I Know my Rights" brigade and of course will all die tragically because they "Know their Rights"

If a pilot doesn't know his rights ie: the constraints of Air Law and the RotA and fails to comply he is also branded an incompetent who shouldn't be flying in the same sky as the rest of the skygods.

Pilots are always being accused of "not complying with spurious and commercially oriented !ATC "Instructions, and lets not try to bury this under the "Safety" argument which means if you disagree you are against safety you Know it all rights brigade villain. As In my experience all of these quasi "instructions" are 100% to expedite commercial traffic at the expense of the "Know their rights pilots"

All this waffle about if you don't comply then whole country will be covered in class D, well let em' apply for it.

[Jonzarno]

The original post on this thread talked about a potential issue with ATC at Cambridge Airport. I am based there, have done over 700 take offs / landings there and have to say that IMHO the Cambridge air-traffic is of the highest standard.

As has been pointed out: Cambridge does not have controlled airspace and I don't think that anybody wants it to. I certainly don't but, equally, we do want the air traffic controllers there to help provide a safe environment.

Cambridge does, however, have a couple of potential safety issues that arise because it does not have controlled airspace:

The gliding site at Gransden is very close to the GPS and NDB approaches to runway 05.

The procedure for the ILS to runway 23 extends 8 miles from Cambridge NDB, turning inbound about two miles from the Lakenheath / Mildenhall MATZ, descending from 3000 to 1700 ft before glideslope intercept at 5 miles and, in addition, there are 10 mile DME arcs to both the north and south.

Quite a number of relatively big fast aircraft fly those approaches every day both as arrivals into Cambridge and for training.

So if a controller does give me an instruction, even if it is in the Class G around the airport, and even if he doesn't phrase it as politely as some might like, I prefer to assume that he's doing it for a good reason and I will comply.

I accept that if a controller issues a silly instruction in uncontrolled airspace such as that described a couple of posts ago the poster was quite right to ignore it and fight his corner. That said, I've never had a silly instruction like that from ATC at Cambridge.

But if it's not obviously silly, I would take the view that the controller knows something that I don't and is getting me to move for a good reason.

In summary: I know my rights, but I am also free to choose not to exercise them.

[bookworm]

I've also been based at Cambridge, for the last 25 years in fact. They've always been a highly professional and capable unit. But no matter how good the controllers are, there's a scope within which they operate, and that is relevant to the application of ATC outside controlled airspace.

If you operate IFR in class A to C, the deal is clear: you fly the trajectory of your clearance and the controller makes sure it is separated from other traffic. The responsibility for collision avoidance is entirely transferred to ATC (except for the final barrier in the safety model of a crew noticing an imminent collision, which always remains with the crew).

As the airspace classification moves further along the alphabet, that responsibility transfer becomes less well delineated. In D there is at least a known traffic environment, but in class G the controller, particularly one providing a procedural service, may well not be aware of the traffic that poses a risk to your flight. The procedural rules deal only with the other aircraft the controller is aware of, and that may be mean the clearance or instruction is designed to separate you from another aircraft 20 miles away and 1000 ft separated in level. The risk management of the flight may dictate that separation from proximate hazards that the pilot knows about is more important than separation from distant hazards that the controller knows about. That doesn't mean just collision avoidance manoeuvres, but steering around known areas of activity, or choosing levels that are less likely to lead to a conflict.

Of course, that doesn't happen all that often, and mostly when a controller makes a suggestion by issuing an instruction, there will be no reason to refuse it. That means that on the rarer occasions when it is necessary to refuse an instruction, the controller may be taken by surprise, and that can lead to a tone of voice that might be confused with annoyance, particularly if it changes their plan. In my experience, most of the good ones get over it pretty quickly.

I don't find it helpful to be "cleared" by a controller when on anything other than a procedural or control service. If I'm "cleared to transit the overhead at 2500 ft" on a basic service, is the controller taking responsibility for not clearing anyone else through the overhead at that level? For that reason, I sympathise a little with the OP if the account is correct. But most of the time, pilots and ATC should manage to co-operate together to make every airspace user a little safer.

[Gertrude the Wombat]

I don't find it helpful to be "cleared" by a controller when on anything other than a procedural or control service. If I'm "cleared to transit the overhead at 2500 ft" on a basic service, is the controller taking responsibility for not clearing anyone else through the overhead at that level?

I would have reasonable confidence that the controller is taking responsibility for not clearing any of his instrument traffic through the overhead at that level, and that if there was other passing VFR trade expected at the same place at the same level at the same time I'd be told about it.

I would not, of course, expect the controller (who may not have radar) to tell me about any VFR bimblers who had chosen (quite legally) not to talk to him.

[abgd]

Going back to the first post, the author wasn't concerned about being instructed to change course - they were bothered about being cleared to do something they intended to do anyway, and had every right to do without clearance.

It's this routine claim on uncontrolled airspace which is objectionable; not the (hopefully) exceptional situation where a controller is trying to avoid a worrisome conflict.