View Poll Results: Who was at fault ?
A at fault
1
2.44%
B at fault
23
56.10%
Both at fault
16
39.02%
Neither at fault
1
2.44%
Voters: 41. This poll is closed
Holding Areas - Who separates ?
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Thanks. The next logical question I guess is, what is the difference between CAS and Un CAS? Why not extend the boundaries of CAS? Is the pilot 'obliged' to follow instructions or can he continue on his own course?
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The difference between CAS and un-CAS is the difference between a known and unknown traffic environment. With the complex and busy airspace of the UK and the competing demands of civil (commercial and GA) and military traffic, airports that do not reach a certain level of traffic/passenger numbers are unable to justify the restrictions on other airspace users of CAS, and the system we have has developed to allow co-existence.
In the interests of brevity, I'll relate your last question to the top level of radar service available outside CAS, the Radar Advisory Service. Under a RAS, the pilot is expected to comply with all instructions as they would under radar control (level, heading, speed etc.) and the controller assumes responsibility for separating the aircraft from other traffic under their control, and for attempting to provide separation from unknown traffic. As this is an 'advisory' service, the pilot can elect not to follow instructions, and then becomes responsible for their own separation.
You can read about it all here in the UK MATS part 1. Section 1, Chapter 5 relates to radar services.
In the interests of brevity, I'll relate your last question to the top level of radar service available outside CAS, the Radar Advisory Service. Under a RAS, the pilot is expected to comply with all instructions as they would under radar control (level, heading, speed etc.) and the controller assumes responsibility for separating the aircraft from other traffic under their control, and for attempting to provide separation from unknown traffic. As this is an 'advisory' service, the pilot can elect not to follow instructions, and then becomes responsible for their own separation.
You can read about it all here in the UK MATS part 1. Section 1, Chapter 5 relates to radar services.
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to chip on on rodan's point...
Unregulated airspace (Class F&G... outside CAS) is an unknown traffic environment. The ATS provided in the UK in such airspace is advisory and does not guarantee separation from other traffic... although ATC will attempt to separate (Most airspace users know this... although I wonder about some of the International flights we get into our airfield that have to transit a chunk of Class G to reach us?)... It is not a perfect system, but there is massive competition/resistance to establishing more regulated airspace and restricting the "rights" of aviationists of all persuasions... and there are plans to increase the amount of "known traffic" airspace, but it's not there yet!
(Sorry if this is repeating what has already been said?)
Unregulated airspace (Class F&G... outside CAS) is an unknown traffic environment. The ATS provided in the UK in such airspace is advisory and does not guarantee separation from other traffic... although ATC will attempt to separate (Most airspace users know this... although I wonder about some of the International flights we get into our airfield that have to transit a chunk of Class G to reach us?)... It is not a perfect system, but there is massive competition/resistance to establishing more regulated airspace and restricting the "rights" of aviationists of all persuasions... and there are plans to increase the amount of "known traffic" airspace, but it's not there yet!
(Sorry if this is repeating what has already been said?)
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B is at fault from an inter unit coordination viewpoint. However the CAA is more at fault from an airspace and regulatory point of view.
Regardless of the situation, unit A agreed to accept traffic from adjacent unit B at FL55.
In the normal situation it is the responsibility of unit B to ensure that the aircraft complies with the coordination agreed before it leaves their area of responsibility.
In my view it is an open and shut case on an inter unit basis. However the CAA is largely at fault and I believe that this example highlights failings in the regulator.
This situation is inherently unsafe in design exactly because there is no controlled airspace.
The controller at B can not clear an aircraft any further than the boundary of controlled airspace i.e. "abc123 cleared to leave controlled airspace on track AB climbing to FL55" or ABC123 cleared to leave controlled airspace to the west climbing to FL55"
Overall, the controller at B has no control over the flight after the airspace boundary.
One would have to investigate the inter-unit agreements and also the demed separations in force between the two holding areas and inbound/outbound routes as well as the RMAs.
For example should the controller at B put the aircraft back into his/her hold until it was level at FL55 or at least kept it within their controlled airspace? If so where is that written down.
If the border between the two unit's area of responsibility is a distance from the controlled airspace boundary the the following clearance would both comply with the CAAs requirement only to clear aircraft to the boundary of controlled airspace and clearly tell the pilot that they are expected to be at FL55 for the next unit.
"ABC123 cleared to leave controlled airspace to the North climbing to FL55. Unit A will accept you level at FL55".
Unfortunately, that CAA approved clearance can result in this situation we are talking about.
If however the inter unit boundary is the edge of controlled airspace then it is easier to define and the clearance is less open to dangerous errors;
"ABC123 leave controlled airspace to the north climb FL55 level by the zone boundary."
Of course if the airfields are very close then the holding area from airfield A may enter the controlled airspace for airfield B
Then of course we have the old problem of the pilot havign left controlled airspace deciding to do some general handling before the next holding exercise. Being outside controlled airspace, that pilot can turn off the radio, play round from the MSA to FL whatever and on completion level the aircraft at FL55 and tune in airfield A and report inbound to the beacon at FL55.
Not to mention that joker G-WXYZ could decide to do a few holds at airfield As beacon at FL50! in IMC with no radio and no transponder at all.
Overall, everyone must agree that whatever the cause the effect is a dangerous situation. It is incumbent on the CAA as the regulator to act to prevent dangerous situations. I believe that simple Class E airspace round such airfields would improve the safety situation drastically without impinging on any VFR pilot's right to go as they please in VMC.
Regards,
DFC
Regardless of the situation, unit A agreed to accept traffic from adjacent unit B at FL55.
In the normal situation it is the responsibility of unit B to ensure that the aircraft complies with the coordination agreed before it leaves their area of responsibility.
In my view it is an open and shut case on an inter unit basis. However the CAA is largely at fault and I believe that this example highlights failings in the regulator.
This situation is inherently unsafe in design exactly because there is no controlled airspace.
The controller at B can not clear an aircraft any further than the boundary of controlled airspace i.e. "abc123 cleared to leave controlled airspace on track AB climbing to FL55" or ABC123 cleared to leave controlled airspace to the west climbing to FL55"
Overall, the controller at B has no control over the flight after the airspace boundary.
One would have to investigate the inter-unit agreements and also the demed separations in force between the two holding areas and inbound/outbound routes as well as the RMAs.
For example should the controller at B put the aircraft back into his/her hold until it was level at FL55 or at least kept it within their controlled airspace? If so where is that written down.
If the border between the two unit's area of responsibility is a distance from the controlled airspace boundary the the following clearance would both comply with the CAAs requirement only to clear aircraft to the boundary of controlled airspace and clearly tell the pilot that they are expected to be at FL55 for the next unit.
"ABC123 cleared to leave controlled airspace to the North climbing to FL55. Unit A will accept you level at FL55".
Unfortunately, that CAA approved clearance can result in this situation we are talking about.
If however the inter unit boundary is the edge of controlled airspace then it is easier to define and the clearance is less open to dangerous errors;
"ABC123 leave controlled airspace to the north climb FL55 level by the zone boundary."
Of course if the airfields are very close then the holding area from airfield A may enter the controlled airspace for airfield B
Then of course we have the old problem of the pilot havign left controlled airspace deciding to do some general handling before the next holding exercise. Being outside controlled airspace, that pilot can turn off the radio, play round from the MSA to FL whatever and on completion level the aircraft at FL55 and tune in airfield A and report inbound to the beacon at FL55.
Not to mention that joker G-WXYZ could decide to do a few holds at airfield As beacon at FL50! in IMC with no radio and no transponder at all.
Overall, everyone must agree that whatever the cause the effect is a dangerous situation. It is incumbent on the CAA as the regulator to act to prevent dangerous situations. I believe that simple Class E airspace round such airfields would improve the safety situation drastically without impinging on any VFR pilot's right to go as they please in VMC.
Regards,
DFC
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Well - we've just had the same happen (in the past few minutes) and the unit was told "Hold active at FL**, join LEVEL FL** +1000ft" (sanitised due to possible reporting action)
Anyone want to change their opinion?
Anyone want to change their opinion?
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DFC
I don't agree... it's nothing to do with the CAA or Class E airspace (although that might be a future solution... but don't hold your breath?)
B may be unable to issue mandatory instructions outside CAS... but still has a responsibility for that flight under ATSORA. The key phrase in ChilliMonster's original post is "pointing straight at" the beacon... it seems B has released the aircraft, following liaison, into known confliction and therefore failed in their duty of care.
I don't agree... it's nothing to do with the CAA or Class E airspace (although that might be a future solution... but don't hold your breath?)
the controller at B has no control over the flight after the airspace boundary
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PPRuNe Radar - I've taken some time and read a few books, but after ten days I've had to admit defeat, I just can't find a way to blame this one on NATS. Sorry to disappoint my man, but there you go. Normal service will resume shortly.
Now, since this is hypothetical, and the two units are obviously fictional
, then I will say this, maybe the co-ordination by both hypothetical ATCO's could have been better to achieve the collective aim.
Possibly giving a heading away from the O bviously F ictional hold would be a good idea in these hypothetical situations, or requesting (hypothetically, of course) that ATCO A will accept the trainer once level at FL55.
However, and I'm no different in these hypothetical situations from time to time as you well know Chilli, maybe ATCO B should have had the hypothetical gumption to not send the trainer to the O bviouslyF ictional hold in the full hypothetical knowledge that another hypothetical flying machine was already, hypothetically speaking, holding at a conflicting level.
Who knows, I'm only an interested obsever on this one, hypothetically speaking.
Now, since this is hypothetical, and the two units are obviously fictional
, then I will say this, maybe the co-ordination by both hypothetical ATCO's could have been better to achieve the collective aim. Possibly giving a heading away from the O bviously F ictional hold would be a good idea in these hypothetical situations, or requesting (hypothetically, of course) that ATCO A will accept the trainer once level at FL55.
However, and I'm no different in these hypothetical situations from time to time as you well know Chilli, maybe ATCO B should have had the hypothetical gumption to not send the trainer to the O bviouslyF ictional hold in the full hypothetical knowledge that another hypothetical flying machine was already, hypothetically speaking, holding at a conflicting level.
Who knows, I'm only an interested obsever on this one, hypothetically speaking.
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Pierre,
The whole idea of safety is to get rid of as many uncertainties as possible. If the CAA had either put the appropriate airspace in place or prevented such operations then we would not be having the debate about a series of what if's.
Even you say - "B may be unable to issue mandatory instructions outside CAS"
It is that "may be" and all the other may be's in the situation that could reduce the level of safety. Thus the professionals at the sharp end are having concerns.
Regards,
DFC
The whole idea of safety is to get rid of as many uncertainties as possible. If the CAA had either put the appropriate airspace in place or prevented such operations then we would not be having the debate about a series of what if's.
Even you say - "B may be unable to issue mandatory instructions outside CAS"
It is that "may be" and all the other may be's in the situation that could reduce the level of safety. Thus the professionals at the sharp end are having concerns.
Regards,
DFC
StandupfortheUlstermen
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Hypothetically speaking, these flights participate in a particular type of service outside CAS and therefore are 'under the control' of ATCO B, unless the a/c commander informs ATCO B otherwise.
Trust me.
Trust me.
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I am finding it difficult to continue with this thread... the hypothetical is merging with real-life... if these events are actually happening then I don't think PPRuNe is the best way to find a safe solution? We should all have SMS systems in place, this is a potential accident (hypothetical or not)... run it through the SMS?
DFC... you last past was so full "what-ifs and maybes" that I haven't a clue what you're talking about?... but I'd be quite interested in who you mean by "the professionals at the sharp end"?
DFC... you last past was so full "what-ifs and maybes" that I haven't a clue what you're talking about?... but I'd be quite interested in who you mean by "the professionals at the sharp end"?
