Cambridge "Airspace"

[Heliplane]

A few times over the past several weeks my routing has taken me directly through the Cambridge overhead - in the Class G airspace above the Cambridge ATZ but below the base of the overlying Class A airspace.

I'm aware of the instrument holding procedure above the airfield and always call Cambridge approach for at least a basic service (and to let them know I will be transiting overhead).

Recently, Cambridge approach has taken to "clearing" me for the transit, implying that they have some formal authority over an overflight outside the bounds of their ATZ. Yesterday, having made contact with Cambridge asap after leaving the Duxford frequency, the controller sounded annoyed that I had not called with regard to my (above ATZ) overflight much sooner.

Clearly I want to know if someone is holding in an area I am transiting and, appreciating that such person may be conducting instrument training, etc, I am happy to climb, deviate, etc in order not to impact their activities (and have often done so). However, it does feel like Cambridge ATC has been slightly overstepping their authority - especially since one can, quite legally, albeit foolishly, fly through that airspace all day without talking to anyone.

Hopefully this is not the start of Cambridge making a play for an necessary Class D airspace grab like Southend...

[soaringhigh650]

ATC in Class G?

That's ain't possible.

You either make airspace controlled so you can control the traffic.
If the airspace is uncontrolled you have no authority over it.

fly through that airspace all day without talking to anyoneHopefully this is the start of Cambridge and others wanting their much needed Class D airspace.

[PA28181]

No different to Farnboro's constant "clearances" through their overhead at 2400' and "transit" approved while outside their ATZ. Cambridge is pretty well out there on it's own and there isn't a really good reason to overfly it, but, if that's your want, so-be it your in class G and have every right to do so. Making the calls you have is more than sufficient to assess the traffic, so why do these airfields have to assert their non existent "authority" all the time. When I was working the old adages of "custom & practice" soon became accepted as the norm and then became "the Rule" this is what they try to instill into everyone.

Hopefully this is the start of Cambridge and others wanting their much needed Class D airspace.

You do say some strange things don't you?

[Heston]

if their choice of language is upsetting you, why don't you just listen on their frequency without calling them? You'd know about instrument traffic they were working and could make your own mind up as to whether to avoid or carry on.


Just sayin'

[PA28181]

if their choice of language is upsetting you, why don't you just listen on their frequency without calling them?

surely there is no "Choice" of language in aviation RT, it should be correct, including the words "clearance" only used by ATCer's in their "bit of sky" which is clearly not the case.

So blundering across an ATZ irrespective of the "right & wrong" in class G argument at an airfield that does have a good mix of traffic on all sorts of approaches is not the best way. As I said before there is enough room around Cambridge to avoid it anyway but it's the OP's choice and lets not give these airfields the encouragement to apply for unneeded class D.

[2 sheds]

Heliplane

Why not address the perceived problem at the time? Having received a "clearance", respond with "no clearance required - remaining above the ATZ".

If the point is not taken, write to the unit Satco and raise it with him/her. Or, of course, it might have been a simple misunderstanding that you wished to transit the ATZ.

2 s

[Heliplane]

Why not address the perceived problem at the time? Having received a "clearance", respond with "no clearance required - remaining above the ATZ".

The "standby for clearance" message from ATC was met with my response that I would be above the ATZ - not as direct as no clearance required (which I may try next time) but certainly implying the same thing.

[fireflybob]

Seems to be spreading. I was working a certain ATSU with a basic service in Class G and called to say I was squawking 7000 and changing to XXXX for MATZ penetration. The reply was "If you receive no reply return to this frequency" - ok maybe it was trying to be helpful but at the time I thought under what authority they were they instructing me to do so?

I appreciate that a controllers job at somewhere like Cambridge can be challenging but we've stopped sending student cross countries there after they started getting picky about visitors at the weekend and appeared to be playing "airports".

[arelix]

The problem with flying "around" such places is the instrument approach traffic may well be 10 miles + from the field, so how much do you avoid?
Perhaps better to talk to them and route overhead, at least they know where you are and can negotiate safe transit.

If they get silly, ask for the SATCO's telephone number and talk to them on the ground about it, worked for me on the few occasions it has been required.

[Gertrude the Wombat]

Perhaps better to talk to them and route overhead, at least they know where you are and can negotiate safe transit.
I sometimes say "I will be passing through your overhead/approach/hold at x,000', does that give you a problem?". Which in most places seems to be replied to by a request to maintain my level, which seems perfectly reasonable - I can see that it could be hard to plan if someone might be going up and down like a yo-yo.

[Talkdownman]

Such posturing doesn't just affect passing aviators. It can affect nearby ATSUs. We are an autonomous radar unit operating in Class G (uncontrolled) airspace. On Jan 23rd this year I reported for TRUCE with a live target, only to find everybody from the previous TRUCE session still sitting around twiddling their thumbs. When I asked what the problem was I was told that the adjacent autonomous radar unit (which similarly operates in Class G uncontrolled airspace) had directed us to keep our target aircraft on the ground until advised solely in the interest of their own operation. Once I had climbed down from the ceiling I insisted that we launch our target, but our manager declined in the interest of inter-unit relations.

The aforementioned adjacent unit has absolutely no authority at all to restrict our, or anyone else's, operation outside regulated airspace. We have a business to run. Such restriction is nothing short of illegal.

[flybymike]

Why not address the perceived problem at the time? Having received a "clearance", respond with "no clearance required - remaining above the ATZ".

If the point is not taken, write to the unit Satco and raise it with him/her. Or, of course, it might have been a simple misunderstanding that you wished to transit the ATZ.

No "clearance" required to transit an ATZ.

[PA28181]

No "clearance" required to transit an ATZ.

Correct if the atsu is AFIS or just A/G

Incorrect if ATC

[TheOddOne]

A part of the ATZ for our local 'big' aerodrome (in Class G) juts out over the sea. One of our residents thinks it is clever to fly UNDER the ATZ (quite legal but very silly).
Generally, if I am able, I will go along with a 'clearance' issued to route above the ATZ, even though we both know such a 'clearance' isn't really valid with a Basic service. I do this on the basis that
a) tomorrow I might be in the overhead myself doing instrument training and appreciate the co-ordination with other traffic
b) I might need to descend into the ATZ to avoid weather etc.
We have regular liaison meetings between all the local airfields and the ATC unit where we can talk about these things over a cuppa. Don't Cambridge do the same thing?

TOO

[Luke SkyToddler]

It's pretty crazy that the instrument approach for Cambridge isn't protected airspace, considering that reasonable numbers of heavy airliners / C130s / bizjets etc all use it on a pretty regular basis.

I know it's "legal" :hmm: to do so, but it's not really common sense. If I was a controller and I had a B747 or a Herc on 4 mile final in IMC, and then a PPL made a "courtesy" contact call just to let me know that he was transiting the overhead, I'd be annoyed too. If the big guy made a go around for whatever reason, you'd be in prime position to go straight through his intakes.

[Gertrude the Wombat]

If I was a controller and I had a B747 or a Herc on 4 mile final in IMC, and then a PPL made a "courtesy" contact call just to let me know that he was transiting the overhead, I'd be annoyed too.
But surely that is helpful?


If the transit is at 4,000' he can be asked politely not to go any lower until clear, and the airliner can be told "not above 3,000'" on the go-around.

[flybymike]

A part of the ATZ for our local 'big' aerodrome (in Class G) juts out over the sea. One of our residents thinks it is clever to fly UNDER the ATZ (quite legal but very silly).

Is it possible to fly under an ATZ?
Do you mean under the stub of a MATZ?
Warton?

[fhl206]

Is it possible to fly under an ATZ?
Do you mean under the stub of a MATZ?
Warton?

If the ATZ juts out over the sea, and the airfield is above sea level, then I suppose you could technically fly below the ATZ which only goes down to ground level/field elevation?

[BillieBob]

One of our residents thinks it is clever to fly UNDER the ATZ (quite legal but very silly)Not only stupid but ignorant as well - it is not possible to fly 'under' an ATZ! By definition (ANO Article 258) an ATZ extends from the surface to a height of 2000ft above the level of the aerodrome. The fact that a part of the surface within the boundary of an ATZ is below aerodrome elevation is irrelevant, it is still part of the notified airspace.

[bookworm]

No "clearance" required to transit an ATZ.

Correct if the atsu is AFIS or just A/G
Incorrect if ATC

No actually, also correct for an ATZ with ATC. The commander must "must obtain the permission of [ATC] to enable the flight to be conducted safely within the aerodrome traffic zone".

A "clearance" is a somewhat more formal contract with ATC. When used in it's purest sense (as in the US system) it promises some level of separation in return for agreeing to fly a specified trajectory. I would concede that in UK usage for class D, it has become little more than a "permission".

On that basis, Cambridge (who are normally pretty good at asking what service is required) should not provide a clearance if you're on a Basic Service, though it would be entirely appropriate if you agree a Procedural Service with them.

the controller sounded annoyed that I had not called with regard to my (above ATZ) overflight much sooner

While you may be correct in your perception, I'd caution against reading too much into an ATCOs tone. All sorts of stuff can be going on to raise workload (and hackles) that you may not be aware of.

[2 sheds]

A "clearance" is a somewhat more formal contract with ATC. When used in it's purest sense (as in the US system) it promises some level of separation in return for agreeing to fly a specified trajectory. I would concede that in UK usage for class D, it has become little more than a "permission".
Rather debatable.

European definition...
Air Traffic Control Clearance - Authorisation for an aircraft to proceed under conditions specified by an air traffic control unit.
= an ATC unit granting permission to operate in an ATZ is passing a clearance.

2 s

[PA28181]

No actually, also correct for an ATZ with ATC.

I did say that didn't I

No "clearance" required to transit an ATZ.

Correct if the atsu is AFIS or just A/G
Incorrect if ATC

[bookworm]

European definition...

Where did you find that 2s? I don't doubt it's in some EU regulation.

I agree the issue is debatable and somewhat academic.

Neither ICAO Annex 11 nor PANS-ATM define "clearance". Annex 11 does say:

3.7.1 Contents of clearances
3.7.1.1 An air traffic control clearance shall indicate:
a) aircraft identification as shown in the flight plan;
b) clearance limit;
c) route of flight;
d) level(s) of flight for the entire route or part thereof and changes of levels if required;
e) any necessary instructions or information on other matters such as approach or departure manoeuvres, communications and the time of expiry of the clearance.

I would argue that "permission granted" does not meet the spirit of this, but then neither do most of the other "clearances" used in the UK.

[2 sheds]

Hi Bookworm

ICAO Annex 2
Air traffic control clearance. Authorization for an aircraft to
proceed under conditions specified by an air traffic control
unit.
Note 1.— For convenience, the term “air traffic control
clearance” is frequently abbreviated to “clearance” when used
in appropriate contexts.
Note 2.— The abbreviated term “clearance” may be prefixed
by the words “taxi”, “take-off”, “departure”, “en route”,
“approach” or “landing” to indicate the particular portion of
flight to which the air traffic control clearance relates.

and EU IR 923/2012 (SERA), Art 2

28. ‘air traffic control clearance’ means authorisation for an aircraft to proceed under conditions specified by an air traffic control unit;

2 s

[PA28181]

So it all comes down to Cambridge were not correct in giving a "Clearance" while overflying the ATZ in Class G, glad that's sorted, only took 2 pages.

[Jim59]

So it all comes down to Cambridge were not correct in giving a "Clearance" while overflying the ATZ in Class G, glad that's sorted, only took 2 pages.

Simple - apart from the fact that the conclusion is incorrect. The following extracts from CAP 493: Manual of Air Traffic Services Part 1 indicate that controllers are permitted to issue clearances to aircraft ouside controlled airspace and whilst aircraft are not REQUIRED to obey there is an expectation that they will unless they advise that they cannot/will not.
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.

Outside Controlled Airspace
1.5 An Approach Control unit at an aerodrome outside controlled airspace shall provide ATS to aircraft, as determined by the Aerodrome Operator and approved by the CAA, from the time and place at which: arriving aircraft place themselves under the control of Approach Control until control is transferred to Aerodrome Control;
departing aircraft are taken over from Aerodrome Control until they no longer wish to receive a service or are 10 minutes flying time away from the aerodrome, whichever is the sooner;
overflying aircraft place themselves under the control of Approach Control until they are clear of the approach pattern and either no longer wish to receive a service or are 10 minutes flying time away from the aerodrome, whichever is the sooner.



Aircraft within an ATZ are required to comply with instructions from the ATC unit. Although flight in Class F and 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.

[JW411]

On 04 February 1965 I was in the right hand seat of Mrs Windsor's Argosy XR138. My captain, in the left seat, was doing his monthly training and was at the time, heads down on instruments flying an NDB hold (left hand) at the 'BO' NDB for Benson about to commence the approach.

The weather was CAVOK. As he turned off the end of the downwind leg of the hold on to the final approach course, he realised that he had turned too tightly and so he rolled the wings level to make an attack on to the ideal bearing.

It was at that moment that my world went into slow motion. I obviously couldn't see into the turn from the right seat but I suddenly had a windscreen full of BOAC VC-10 moving left to right. I grabbed control and tried to go down and right but everything had gone into very slow motion. It was like every second took an hour.

We just missed.

I saw the first officer in the VC-10 and I watched every single window in slow motion go past me. For some reason or another I do not remember seeing the wingtip.

To me, the most surreal part was watching the slightly black trail of the VC-10 engines disappearing into the distance without so much of a single degree of a heading change. They had simply not seen us.

Needless to say, we gave up what we were supposed to be doing and landed and fairly promptly, went down to the Farmers Man in Benson village for a quick nervous breakdown.

A couple of weeks later, I was called by a Wg Cdr in Flight Safety at MOD and he wanted to know how I knew that the VC-10 concerned was G-ARVH. I told him that I had read it off the tail-bullet. "Bloody Hell" said he "you must have been close!"

It transpired that the VC-10 was on its way from Wisley to Bedford to do some blind landing trials and they had decided to go VFR at 3,000 feet via Woodley and they admitted afterwards that they had disgegarded military holding patterns for Benson, to them, Benson was simply an ATZ.

I dreamed about the encounter for quite a while.

I therefore find it quite pathetic to find fellow private pilots (I presume) arguing about the semantics of what they think an ATC unit actually said to them which so upset their afternoon bimble when THEY KNOW THEIR RIGHTS!

For God's sake people, communicate with one another. It is quite amazing what you can achieve if you are nice to each other.

It is so much better than waking up in the middle of the night in a muck sweat trying to work out why you are still alive despite others.

[Crash one]

JW411
Well said sir.
Makes a nonsense of the whole "I have my rights" debate.:ok::ok:

[PA28181]

Outside Controlled Airspace
1.5 An Approach Control unit at an aerodrome outside controlled airspace shall provide ATS to aircraft, as determined by the Aerodrome Operator and approved by the CAA, from the time and place at which: arriving aircraft place themselves under the control of Approach Control until control is transferred to Aerodrome Control;
departing aircraft are taken over from Aerodrome Control until they no longer wish to receive a service or are 10 minutes flying time away from the aerodrome, whichever is the sooner;
overflying aircraft place themselves under the control of Approach Control until they are clear of the approach pattern and either no longer wish to receive a service or are 10 minutes flying time away from the aerodrome, whichever is the sooner.

As the OP wasn't "arriving" ie landing" this quote is irrelevant.

Aircraft within an ATZ are required to comply with instructions from the ATC unit. Although flight in Class F and 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.


As the OP was outside the ATZ the first part of quote is irrelevant. The rest fails to take account of the current "ATSOCAS" requirements

Is the manual required reading/study for ppl's?

[bookworm]

overflying aircraft place themselves under the control of Approach Control

Would you not associate "place themselves under the control of" with acceptance of a procedural service though?

[PA28181]

As ATSOCAS exists, a "procedural" service is

A Procedural Service is a non surveillance service in which deconfliction advice is provided against other aircraft in receipt of a Procedural Service from the same controller. The avoidance of other aircraft is the pilot’s responsibility.

As a "deconfliction/procedural" is only available to flight under IFR the OP cannot comply/request if VFR.

[Jim59]

Is the manual (of Air Traffic Services Part 1) required reading/study for ppl's?

Not normally, but if one is going to publicly claim that ATCO's are not doing their job correctly by exceeding their powers, as done early in this thread, then it is helpful to know their job description as laid down in their ‘bible’ MATS Part 1. MATS Part 2 also exists but is not generally available since it is each unit's local procedures as approved by the CAA.


For what it's worth, I frequently fly a glider in the vicinity of Cambridge Airport under a basic service and feel that I get an excellent service. Sometimes I get a clearance I cannot comply with (like maintain 4,000’ – but to be fair that’s more likely to come from Lakenheath), I explain why I cannot comply and come to a more appropriate agreement. It’s not a problem.
Especially when they have instrument traffic in the hold, or on approach outside controlled airspace, working in the way laid down in MATS Part 1 creates a safer environment for all. Most of the instrument traffic seems to be training in light aircraft with relatively few commercial movements.




Willing acceptance of and compliance with their clearances OCAS is to our benefit since they are LESS likely to feel they have to go for Class D which means that we can be excluded.

[2 sheds]

For what it's worth, I frequently fly a glider in the vicinity of Cambridge Airport under a basic service and feel that I get an excellent service. Sometimes I get a clearance I cannot comply with (like maintain 4,000’ – but to be fair that’s more likely to come from Lakenheath),

Jim59

Under a BS, I trust that the "clearance" to which you refer is actually "for co-ordination, request you..." which is a perfectly routine request under BS.

2 s

[Jim59]

Dialogue is usually along lines:

Pass your message.

Glider XXX is 4 miles North West of your field at 4000’ routing overhead towards the wind farm. Request Basic Service.

Glider XXX, QNH is nnnn. Basic Service. Report descending below 2500’.

Nnnn, Basic Service. WILCO. Glider XXX


However on occasion I have been “cleared” overhead. Sometimes I'm instructed to report on reaching a certain point such as overhead or after completion of crossing of extended centre-line etc..

[tmmorris]

Flying overhead Cranfield a very common experience is I report my level and routing (via the beacon), and they ask if I am VFR or IFR. In the usual UK 'IFR exists only in your own head OCAS' situation, I am usually IFR, I.e. I have chosen a level consistent with my heading IFR and am above MSA so I can be IFR if I want.

They don't want me IFR because they will then have to deconfiict me from the IFR training traffic so they usually request I overfly them VFR. If I am in VMC I comply but it does make a bit of a nonsense of the idea of procedural deconfliction...

[BillieBob]

I have chosen a level consistent with my heading IFR and am above MSA so I can be IFR if I want.Provided, of course, that you have a valid instrument rating.

[2 sheds]

They don't want me IFR because they will then have to deconfiict me from the IFR training traffic


No, they don't - not if you request only a BS.


2 s

[Gertrude the Wombat]

They don't want me IFR because they will then have to deconfiict me from the IFR training traffic so they usually request I overfly them VFR
I passed by Cranfield the other day and gave them my estimate and level for the CIT, which happened to be directly on my route, which might have made me sound like IFR traffic. They seemed quite keen to make it clear that they were treating me as VFR - didn't bother me one way or the other!

[piperboy84]

In the UK is it accurate to say that when crossing CAS asking for a "clearance" implies IFR, asking for a "transition" is VFR?

[dont overfil]

In the UK is it accurate to say that when crossing CAS asking for a "clearance" implies IFR, asking for a "transition" is VFR?
No. I've not heard transition used in the UK. Nearest is clearance to transit.
Either way ATC will ask if you are VFR or IFR.

D.O.

[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]

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.

[2 sheds]

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.

Or to put in another way, the controller used a term which, strictly speaking, he should not have used in the case of BS traffic - unless, of course, he was implying that the aircraft could transit the ATZ if required? The implication might well have been, I suggest, that there was no traffic problem in directly overflying the airport, whether through the ATZ or just above it, and that no co-ordinated specific level or route was required to avoid confliction with circuit or PS/DS traffic. Also, the OP knew the procedures and his rights - good for him - so what was the practical problem?

How does this then deteriorate into accusations of "airspace grabs"? - a ridiculous term that does not exactly suggest reasoned argument or promote the case for the opposition!

2 s

[Gertrude the Wombat]

so what was the practical problem?
Exactly ... the controller could have spelt all that out in words of one syllable (apart from the liberally scattered two syllable "request") and kept the OP happy ... at the expense of pissing off everyone else who was trying to get a word in on a busy frequency.

[soaringhigh650]

How does this then deteriorate into accusations of "airspace grabs"? - a ridiculous term that does not exactly suggest reasoned argument or promote the case for the opposition! It's historical.

In the same way as Stanstead would grab the whole runway and create $350+ fees to kick light airplanes outta there, NATS would grab as much Rule 21 or Class A airspace designed to deliberately exclude VFR flights, and then add a $170+ navigation service charge for an approach into Stanstead.

If it ain't a grab then what is it?

[2 sheds]

A minor phraseology discussion point, perhaps - blown out of all proportion by a few with a tired old axe to grind?


And by the way, the spelling is Stansted.


2 s

[Keef]

I've not had a problem with Stansted, never been charged a navigation service fee, and been allowed to orbit over their runway with some WW2 aircrew. They've been nothing but polite.

If when I listen they are frenetically busy, then I go round the outside with their listening squawk on.

Elsewhere I've been asked, in Class G on a basic service, if I could maintain X feet or Y track because of an incoming 747. I was happy to comply: it was all done politely.

If the argument is about which word the ATCO used, well....

[Sir Niall Dementia]

And Stansted controllers, like Cambridge, Gatwick, Luton, Oxford, Exeter, Bristol, Farnborough and anywhere else that handles volume IFR traffic really appreciate a call as early as possible to negotiate your crossing. You may be legally allowed to cross the Cambridge ATZ at 3500, VFR without chatting, but you would look a tad daft if you collected a Gulfstream, AirBus or Hercules through your windscreen, who was holding, also perfectly legally at 3500' IFR. Perhaps a very hard working controller used the wrong phraseology at a busy time, we all do it, it certainly isn't worth a lot of angst.

What worries me for my private flying is that late calls about overhead transits, no calls at all about transits, people switching off transponders and flying an ILS to 2 miles (outside the ATZ, so what the heck) and then turning away and switching them on again, people who fly through instrument approaches in Class G without talking (lets face it, its' class G so the big jet on a stable approach with a crew concentrating on the approach they are flying will have to give way to my PA28 because I'm on their right) are all arguments the airport operators use to get CAS, and they work, with CAA, councils, and residents associations (lets face it get the noise whiners on side and its' game, set and match to CAS). Just for info I have seen each one of the forgoing list in the last 12 months at my home base. (and the bright spark flying the ILS IMC without talking, with his transponder off really spilt the gin in the back, and the go-round back into the procedure cost 54 quid a minute)

As GA we bleat about CAS, but I wonder if we really help ourselves. I spent most of my day job in CAS and there is quite a lot around, I'd really rather do my fun flying in Class G while we have some left.

SND

[Gertrude the Wombat]

the bright spark flying the ILS IMC without talking, with his transponder off
Isn't that worth an "endangering" charge if caught?

[tmmorris]

Must be if he flew below MSA - that's an infringement of the ANO.

[abgd]

are all arguments the airport operators use to get CAS, and they work

Speaking personally, I don't find limited radio mandatory zones or reasonably sized chunks of airspace to be unreasonable requests. It's things like the Farnborough proposal that are bothersome.

[Sir Niall Dementia]

Gertrude/Tmmorris;

You are both right, the difficult bit is pinning down who he was and where from to be able to file on him. It was a monumentally silly thing to do, and I doubt he saw us in his six o'clock at very close followed by a full power pull up over him climbing like a dingbat. I saw enough to realise he was a 182 and that was it.

If I had caught him wing tip to wing tip I doubt I would have felt more than a thump and seen some witness marks on the winglet after landing, as it was he was about to come through the windscreen at around 1700' in solid cloud, I got a view of about two seconds as I hit the TOGA buttons and pulled the stick back. I had no idea my heart rate could go so high!

Basically it was poor airmanship, if he had spoken ATC they would have happily taken him for a practise ILS and we could have ensured separation and that is what ATC is really all about, keeping us apart in the air, it is so much easier for them to do it if we talk early and arrange the ATC/Pilot "contract" that they discuss so much in MATS part one.

Just my thoughts.

SND

[soaringhigh650]

A minor phraseology discussion point, perhaps - blown out of all proportion by a few with a tired old axe to grind?Excuse me, but if airports and airspace is being used to kick out light airplanes then this certainly ain't 'minor' in any shape or form.

It's an extremely major point of discussion.

[2 sheds]

sh650


I really do not follow the logic. The OP was making a point, which to a degree was justified, about the precise phraseology. He was obviously well aware of the rules of engagement and furthermore was voluntarily opting for a Basic Service from Cambridge Approach. And had there been any more significant factor involved in ATC exceeding the terms of a BS, I am sure that he would have made this clear to the controller.


With the controller - possibly - very slightly exceeding the terms of a BS (but in practical terms, being more helpful), how does this suddenly become "airports and airspace...being used to kick out light airplanes"?


2 s

[soaringhigh650]

You said an "airspace grab" was a ridiculous term.

I explained where the term came from and said if it ain't a grab then what is it?

You replied and said it was a "minor phraseology discussion point".

I replied and said it's not minor.

Do you follow now?

[2 sheds]

Do you follow now?

Nope! The subject matter was a relatively minor and debatable phraseology/terminogy issue which was then alleged to be "evidence" that Cambridge ATC was attempting to take control of airspace outside their ATZ in Class G airspace. I do not understand how that might help to achieve Class D status for them.

2 s

[Jonzarno]

As I said earlier, I'm based at Cambridge. As far as I know, Cambridge has no ambition to establish Class D airspace. For one thing, I believe it would require them to staff the radar full time which would be expensive and not justified by the traffic they have.

[Gertrude the Wombat]

As far as I know, Cambridge has no ambition to establish Class D airspace.
Last I heard (and as a then councillor I did get invited to things that weren't open to the public) they were, in fact, thinking about it. But that was over a year ago, and there have been several changes of airline using the airport since then, or at least that's what it feels like, and the views may change with the customers.

[soaringhigh650]

The subject matter was a relatively minor and debatable phraseology/terminogy issue which was then alleged to be "evidence" that Cambridge ATC was attempting to take control of airspace outside their ATZ in Class G airspace. I do not understand how that might help to achieve Class D status for them.

Okay I wasn't quoting in the context of previous posts but I see your point now. You should see mine too.

[Jonzarno]

As far as I know, Cambridge has no ambition to establish Class D airspace.


Last I heard (and as a then councillor I did get invited to things that weren't open to the public) they were, in fact, thinking about it. But that was over a year ago, and there have been several changes of airline using the airport since then, or at least that's what it feels like, and the views may change with the customers.

Thanks for posting this. That is interesting:I hadn't realised.

I think the basic point remains though: in order for them to want class D, they would need a volume of commercial traffic sufficient to justify employing sufficient radar controllers to man the radar during all opening hours; and I can't see that happening at current levels.

[soaringhigh650]

in order for them to want class D, they would need a volume of commercial traffic sufficient to justify employing sufficient radar controllers to man the radar during all opening hours; and I can't see that happening at current levels.

In the USA you don't need radar or commercial traffic to justify class D. If the FAA determines that an airport requires a tower controller then you automatically get it.

[Sir Niall Dementia]

And in the UK the airport applies for it, there is a stonking great consultation process with everyone invited to comment, PPrune lights up with indignation and they still may not get it.


Its' one of the joys of UK/EASA aviation.

[beerdrinker]

SoaringHigh,

Unfortunately there is a difference between the US Class D airspace and the UK's. In the States it is very much like the UK Radio Mandatory Zone (RMZ). You call the controller, make contact and tell him what you are doing. In the UK Class D is controlled airspace and you have to have positive clearance to enter.

[no slots]

So, what is the problem with calling up for a clearance?

[Good Business Sense]

I've almost given up asking for a clearance through Class D airspace

Seems, with some units, even one aircraft makes them too busy to issue a clearance - so I just plan to avoid - more time and more miles and therefore, more money in the planning but, these days, it's always a lot less than the actual reality of holding etc etc waiting for the aircraft on a 4-8 mile final to land before you get to move .... can't be too careful !

I do a lot of hours - this is the norm. in the UK.

[FullWings]

I think some of the problem is the complex low level airspace we have in the UK, mixed in with the proximity of many airfields to each other.

If you plot instrument approaches, circuit patterns, holds, extended centrelines, etc. on a map of SE England, it becomes clear that if you fly a route from A-->B, it is virtually impossible not to cross somebody’s patch without weaving left, right, up and down like an inebriated insect.

Add in that you need about five radio boxes if you want to keep in contact with nearby airfields who might have traffic information. It’s little wonder that many don’t bother at all and rely on see-and-avoid in accordance with the Rules of the Air, ACAS, FLARM, etc. It is class G, after all, and just because you’re talking to ATC doesn’t give you a magic +3 Envelope of Protection...

[englishal]

I've almost given up asking for a clearance through Class D airspace
Can I just comment that I think that is down to you and not ATC.

I can't remember the last time I was refused a D transit, and when I flight plan I draw a straight line on the map and only adjust it for Class A (if I am going somewhere).

Only the other day I went across Bristol and back again later. However first time was 6000' and the second time was FL70. In fact on the way back from N wales, I called London info (as there was no one else to talk to) and in my initial call told them I was crossing Bristol airspace. London gave me a Bristol code and already informed Bristol. When I got closer I called BRS, and got the transit no worries.

My tip is fly as high as you can then when you call them:

Who you are: I am a TB20 from A to B VFR
Where you are: FL60 20 miles south of Brisol
What you want: Request traffic service and transit your CAS from Wells mast via the overhead FL60.

[phiggsbroadband]

Class D is not the end of the world for GA, especially in the Manchester and Liverpool zones. I have had some very pleasant transits of both zones, whilst listening to the A380, B787 traffic.
What made my day a few years ago, was when Manchester approved an orbit of Joderal Bank but at not more than 700 ft.
Also the transits of Liverpool Pier Head and Container Port at 1000ft are well worth it.


Just recently one member of our C172 group over-flew the three Queens in Liverpool Dock, followed by an overhead of Hawarden where the Red-arrows were all lined up on the Taxiway... Was that just good luck or good management...

[Gertrude the Wombat]

"Join right downwind runway 23, not below 2,000' over the city, we have an IFR departure."

"Unable to comply due cloud base."

By the time the airliner was actually ready to roll I was in the normal place on a left downwind, having crossed the climb-out tens of seconds earlier.

Puzzling thing is that I'm surprised ATC didn't know where the cloud base was. (I could have accepted a climb into cloud and an ILS, but I didn't want to.)

[2 sheds]

"Join right downwind runway 23, not below 2,000' over the city, we have an IFR departure."

Really? - what is that supposed to achieve? Is that the whole story?

2 s

[Gertrude the Wombat]

I think that was supposed to achieve my not flying through the climb-out and thereby getting in the way of the departing IFR traffic (I was doing an anti-clockwise orbit of the city so my passenger could do some sightseeing).

But as it happened the IFR traffic was sitting on the runway writing down clearances and stuff for at least another minute and a half, so there wasn't a conflict.

[Jim59]

Asking for a clearance into Class D airspace may not be a big issue for aeroplanes, but in a glider without a transponder the probability of an entry clearance is negligible. Class D airspace is a significant obstacle for gliders.

[soaringhigh650]

the probability of an entry clearance is negligible. Class D airspace is a significant obstacle for gliders. Why is that? Can't ATCers grant suitable clearances?

I'm doubtful that the solution to the problem is to keep it Class G or E so that people can continue gliding undetected and directly into the path of IFR traffic.....

[mm_flynn]

Why is that? Can't ATCers grant suitable clearances?

.....
I think a glider operating no transponder, not maintaining an altitude, unlikely to maintain a heading or location, potentially in and out of cloud, and presenting an intermittent primary target is a difficult thing to either call as traffic (if it is VFR) or provide separation against (if it is IFR). Moreover, UK ATC seem to have an imposed requirement to provide sufficient separation between IFR and VFR (in all airspaces - CDFG) to avoid a TCAS TA or a commercial crew seeing an aircraft separated from them by less than IFR vs IFR minimums.

These two issues probably explain why UK glider pilots feel UK ATC is unlikely to clear them into Class D airspace. (In that the glider pilots are probably correct, and ATC's approach is probably reasonable, given the rules they are held to)