Clearances that are impossible to accept
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Clearances that are impossible to accept
A couple of weeks ago I was flying VFR on an aerial photography flight. The site we were to photograph was in Oldham, in the Manchester CAS. With around 25 miles to run, I made the inital call to Manchester, gave the details of the flight etc. I was told "Call me with 10 miles to Oldham, cleared to enter CAS not above 2000' on the QHN...etc
At this point I was at 3000' with a ridge of high ground (a peak height a mile to the left of my track was shown at 2100')
A descent to 2000' by the zone boundry would have been impossible. (May be would have cleared the ridge by say 50' but I wasn't interested in finding out!)
At the required point I called as required but requested to maintain 3000' for a further 5 miles for terrain clearance.
This was granted and gave sufficient (just) clearance before descending inside the zone.
Now, I am fully aware it is the pilots responsibility to maintain terrain clearance. It certainly wasn't a problem in the very good visability at that time and I wouldn't have been mucking around at low level near hills if the weather had been poor.
However, an unquestioning acceptance of the controllers instructions to be not above 2000' by the zone boundry would have put me into conflict with the terrain. Presumably you guys are aware of the high ground. Is it a good idea to give instructions like this, thatmaybe a less expereinced pilot, particularly if the weather was bad and he or she was stretched, might have accepted and could have got them into deepest trouble?
PLEASE NOTE I am not critising the service I recieved on the day or any other ATC service. Just a genuine question on your general policy, regardless of what the books say.
At this point I was at 3000' with a ridge of high ground (a peak height a mile to the left of my track was shown at 2100')
A descent to 2000' by the zone boundry would have been impossible. (May be would have cleared the ridge by say 50' but I wasn't interested in finding out!)
At the required point I called as required but requested to maintain 3000' for a further 5 miles for terrain clearance.
This was granted and gave sufficient (just) clearance before descending inside the zone.
Now, I am fully aware it is the pilots responsibility to maintain terrain clearance. It certainly wasn't a problem in the very good visability at that time and I wouldn't have been mucking around at low level near hills if the weather had been poor.
However, an unquestioning acceptance of the controllers instructions to be not above 2000' by the zone boundry would have put me into conflict with the terrain. Presumably you guys are aware of the high ground. Is it a good idea to give instructions like this, thatmaybe a less expereinced pilot, particularly if the weather was bad and he or she was stretched, might have accepted and could have got them into deepest trouble?
PLEASE NOTE I am not critising the service I recieved on the day or any other ATC service. Just a genuine question on your general policy, regardless of what the books say.
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Without wishing to enter into a debate about whether the controller was at fault or not (that's bound to follow)... from the pilot's perspective if faced with a clearance you are unable to accept, like this... a quick reply "unable to comply..." works wonders, with perhaps the addition "... due to terrain clearance". That should explain the problem and wake up (if necessary) the controller to the problem in the clearance issued?
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The pilot is responsible for terrain clearance. The only time he is not is when he is being vectored. However I think some controllers have too much faith in our situational awareness. On the other hand, pilots tend to trust a clearance as a safe path.
My opinion is that if you are not flying standard routes, then both you and the controller have to improvise, and for that reason you must be more alert.
My opinion is that if you are not flying standard routes, then both you and the controller have to improvise, and for that reason you must be more alert.
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Jump Complete
"At this point I was at 3000' with a ridge of high ground (a peak height a mile to the left of my track was shown at 2100') "
Now I may be getting the wrong end of a sharp stick here but if the ground is a mile to left of your track how will it impinge on your descent to 2000'? I am sure that a controller would not give you a level that was impossible to fly to enter CAS on. I think that from the reading of your post several times you may be getting the levels allocated to aircraft confused due to your flight rules.
If you are IFR the pilot is responsible for his terrain clearance ( 1000' above the highest fixed obstacle in a radius of 15 miles?) initially, and then the controller will allocate a level that is terrain safe (no pun intended!) depending on the service that is being provided.
If you are VFR then the controller will allocate a level to enter on, you do not have to descend immediately only descend so that you will enter at the specified level.
You initial post was interesting and lengthy but I feel that we are missing out on some more information.
TS
"At this point I was at 3000' with a ridge of high ground (a peak height a mile to the left of my track was shown at 2100') "
Now I may be getting the wrong end of a sharp stick here but if the ground is a mile to left of your track how will it impinge on your descent to 2000'? I am sure that a controller would not give you a level that was impossible to fly to enter CAS on. I think that from the reading of your post several times you may be getting the levels allocated to aircraft confused due to your flight rules.
If you are IFR the pilot is responsible for his terrain clearance ( 1000' above the highest fixed obstacle in a radius of 15 miles?) initially, and then the controller will allocate a level that is terrain safe (no pun intended!) depending on the service that is being provided.
If you are VFR then the controller will allocate a level to enter on, you do not have to descend immediately only descend so that you will enter at the specified level.
You initial post was interesting and lengthy but I feel that we are missing out on some more information.
TS
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You say that you were carrying out aerial photography and therefore I assume that you were operating for hire and reward on a public transport licence, and therefore you have at least a CPL.
Under the circumstances, it would be reasonable for the atco concerned to assume that you fully understood what a SPECIAL VFR clearance means, if you weren't able to comply with the clearance, you should have said so immediately.
The same applies to any other pilot wishing to transit controlled airspace under special VFR - they should understand the implications before they even get airborne.
Under the circumstances, it would be reasonable for the atco concerned to assume that you fully understood what a SPECIAL VFR clearance means, if you weren't able to comply with the clearance, you should have said so immediately.
The same applies to any other pilot wishing to transit controlled airspace under special VFR - they should understand the implications before they even get airborne.
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RYR-738:
I think that, whilst terrain seperation could be considered a shared responsibility whilst under radar vectors, it still remains the ultimate responsibility of the PIC.
Hence the absolute requirement for pilots to maintain SA and advise ATC if any clearance is unacceptable, for any reason.
We can descend below MSA, IMC, if under 'positive radar control', but that does not absolve us from maintaining awareness of terrain and our overall position - we still carry the can if things go wrong!
The pilot is responsible for terrain clearance. The only time he is not is when he is being vectored.
Hence the absolute requirement for pilots to maintain SA and advise ATC if any clearance is unacceptable, for any reason.
We can descend below MSA, IMC, if under 'positive radar control', but that does not absolve us from maintaining awareness of terrain and our overall position - we still carry the can if things go wrong!
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Some years ago the LHR SVFR controllers would give clearances to be at the zone boundary North of Burnham at 1000'.
I took a couple of them for a little flight over the Chiltern Hills showing them what chimney pots look like from the side, and soon after that the clearance became 1500' by the boundary 1000' by BUR
I took a couple of them for a little flight over the Chiltern Hills showing them what chimney pots look like from the side, and soon after that the clearance became 1500' by the boundary 1000' by BUR
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Oldham is around the 700' amsl mark so I can only assume the controller was basing terrain awareness and the ATC clearance on that. The controller has no remit to tell you what to do outside CAS, and as no clearance can be given, then their responsibility can't start until the boundary. The clearance will be 'safe' from that point onwards, all things considered.
If you can't make the clearance because of other factors which are your responsibility to take account of, then shout up and advise ATC that you won't be able to make the restriction due to terrain, cloud, or whatever. As you found, an alternative clearance can usually be given.
It's not a criticism of Jump Complete since he/she has done exactly as they should have and spoken up to ATC but maybe it's a sign of our increasingly litigious society and the 'nanny state' that a section of society always seems to be looking for others to get them out of trouble and not take responsibility for their own actions and laid down responsibilities. What would cause a pilot to blindly follow an ATC instruction which does not apply to their current location, which would take them in to terrain which they can possibly see, or in to bad weather and cumulo granite when they know they are not qualified to do so. Is it this ? Because 'ATC told me to'. Is it poor training received or poor knowledge retention of self preservation strategies on some pilot's parts ? Or do some just prove Darwins theory ? I wish I knew !!
It's been mentioned in other threads on PPRuNe that access to CAS should be given more to pilots, particularly in busy airspace (e.g Heathrow area). One of the planks of this argument is that ATC should trust pilots, accept that they can aviate, navigate, and communicate competently. They are licenced after all. Yet here we see an inference that sometimes we maybe can't trust pilots to do the right thing. To fly beyond their capabilities and get themselves in trouble just because we give them a clearance which is safe inside CAS but they somehow can't think for themselves about how they are going to get to that point safely and won't adjust their flight path or ask for an alternative to ensure they don't become another statistic.
As Devils Advocate ... I don't think pilots can have it both ways as a general principle (as an ATCO, dealing with emergencies and duty of care if ATC notice any pilot errors would override any principle always) . It's either a mutual trust and an acceptance that the pilot has serious responsibilities they can cope with which ATC let them get on with. Or it's a 'nanny state' hand holding all the way with the pilot making sure that ATC are happy that he even breathes. As a pilot and an ATCO, I know which I think it should be.
Food for thought and an interesting topic. Thanks Jump Complete
If you can't make the clearance because of other factors which are your responsibility to take account of, then shout up and advise ATC that you won't be able to make the restriction due to terrain, cloud, or whatever. As you found, an alternative clearance can usually be given.
It's not a criticism of Jump Complete since he/she has done exactly as they should have and spoken up to ATC but maybe it's a sign of our increasingly litigious society and the 'nanny state' that a section of society always seems to be looking for others to get them out of trouble and not take responsibility for their own actions and laid down responsibilities. What would cause a pilot to blindly follow an ATC instruction which does not apply to their current location, which would take them in to terrain which they can possibly see, or in to bad weather and cumulo granite when they know they are not qualified to do so. Is it this ? Because 'ATC told me to'. Is it poor training received or poor knowledge retention of self preservation strategies on some pilot's parts ? Or do some just prove Darwins theory ? I wish I knew !!
It's been mentioned in other threads on PPRuNe that access to CAS should be given more to pilots, particularly in busy airspace (e.g Heathrow area). One of the planks of this argument is that ATC should trust pilots, accept that they can aviate, navigate, and communicate competently. They are licenced after all. Yet here we see an inference that sometimes we maybe can't trust pilots to do the right thing. To fly beyond their capabilities and get themselves in trouble just because we give them a clearance which is safe inside CAS but they somehow can't think for themselves about how they are going to get to that point safely and won't adjust their flight path or ask for an alternative to ensure they don't become another statistic.
As Devils Advocate ... I don't think pilots can have it both ways as a general principle (as an ATCO, dealing with emergencies and duty of care if ATC notice any pilot errors would override any principle always) . It's either a mutual trust and an acceptance that the pilot has serious responsibilities they can cope with which ATC let them get on with. Or it's a 'nanny state' hand holding all the way with the pilot making sure that ATC are happy that he even breathes. As a pilot and an ATCO, I know which I think it should be.
Food for thought and an interesting topic. Thanks Jump Complete
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Why didn't you fly round the high ground? Just because your track A -> B takes you over the ridge, doesn't mean you have to stick to it! Also, VFR flights are normally given 'not above 2', but doesn't mean that you can't ask for higher.
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Just to point out what I meant in my previous post here is an example. You are 30 miles out, inbound and being handed over to Approach. "Radar contact, descend 2000, heading 010" You know that the MSA is 3000. But of course you descend as instructed. On vectors, the ATCO is responsible for your terrain separation. In every other circumstance, the pilot is responsible.
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No no no no no.
PIC is ALWAYS ultimately responsible for terrain clearance, EVEN under radar vectors.
You smack it into high ground while under vectors and see if your wife gets any life insurance back once the 'pilot error' lawyers have finished!
Not to say the ATCO wouldn't get a bit of debrief as well, mind.
PIC is ALWAYS ultimately responsible for terrain clearance, EVEN under radar vectors.
You smack it into high ground while under vectors and see if your wife gets any life insurance back once the 'pilot error' lawyers have finished!
Not to say the ATCO wouldn't get a bit of debrief as well, mind.
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I don't think the argument over who is responsible is the answer (it is always the PIC!). The question is about good or bad clearances. In some circumstances, the above clearance may be considered a contributory factor to an accident perhaps?
Its like having gear and flap levers in the same place and of the same design - its the PIC's responsibility to grab the right one, but the design leaves a bit to be desired.
Its like having gear and flap levers in the same place and of the same design - its the PIC's responsibility to grab the right one, but the design leaves a bit to be desired.
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Quite.
I would say, though, that the difference between causal and contributory factors is fairly insignificant when all that is left of you is a couple of front teeth and 6" of lower intestine; following a high-speed encounter with terrain.
It IS important that ATC procedures are designed, and applied, with the lowest common denominator in mind: i.e. the pilot who does NOT take responsibility for his/her own terrain separation - the importance of good two-way communication in both the planning and operational stages is something that I do not underestimate, believe me..
It's still important to recognise those responsibilities which remain ours, even if we obtain assistance in discharging them.
I would say, though, that the difference between causal and contributory factors is fairly insignificant when all that is left of you is a couple of front teeth and 6" of lower intestine; following a high-speed encounter with terrain.
It IS important that ATC procedures are designed, and applied, with the lowest common denominator in mind: i.e. the pilot who does NOT take responsibility for his/her own terrain separation - the importance of good two-way communication in both the planning and operational stages is something that I do not underestimate, believe me..
It's still important to recognise those responsibilities which remain ours, even if we obtain assistance in discharging them.
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It is of course important to bear in mind who is responsible.
I do hate the modern way of saying "I'm immune from blame as I am not responsible". That is similar to "we ought to do this to cover ourselves".
What we really should be saying is "lets point out this problem as that poor bloke might be caught out" or "lets do this because it is a good idea".
I'm not critiscising any of the posters here, but I love the way aviation in general has a fix it and safety attitude. Unfortunately I see too many litigious attitudes, which work counter to the good ideas which have made aviation amazingly progressive.
Gary - your last sentence sums it up very well.
I do hate the modern way of saying "I'm immune from blame as I am not responsible". That is similar to "we ought to do this to cover ourselves".
What we really should be saying is "lets point out this problem as that poor bloke might be caught out" or "lets do this because it is a good idea".
I'm not critiscising any of the posters here, but I love the way aviation in general has a fix it and safety attitude. Unfortunately I see too many litigious attitudes, which work counter to the good ideas which have made aviation amazingly progressive.
Gary - your last sentence sums it up very well.
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I made the mistake of not being specific enough on another thread just a few days ago. I'll try not to do it again.
The P1/PIC is always ultimately responsible for not banging into the gound. As a controller, the only time that I have to assign levels that are terrain safe is when I am vectoring an aircraft - at other times I assign clearances to a fix that are traffic safe and it's the pilot's responsibility to arrange the flight profile so as not to hit anything. It's a moot point whether I am required to issue terrain safe level and route clearances when I'm just watching an aircraft on radar.
But all of this essentially applies to IFR traffic - the original question was about a VFR flight. Under the normal straightforward, plain vanilla, VFR that the question appears to relate to, the pilot is entirely responsible for avoiding collisions with the ground or anything else. (Please don't ask about the other flavours of VFR!).
In the past I have known some units and individual controllers that have routinely issues clearances that cannot be complied with (at least, not without breaking some rule or other or applying a very liberal intepretation) but this seems far less common these days.
The P1/PIC is always ultimately responsible for not banging into the gound. As a controller, the only time that I have to assign levels that are terrain safe is when I am vectoring an aircraft - at other times I assign clearances to a fix that are traffic safe and it's the pilot's responsibility to arrange the flight profile so as not to hit anything. It's a moot point whether I am required to issue terrain safe level and route clearances when I'm just watching an aircraft on radar.
But all of this essentially applies to IFR traffic - the original question was about a VFR flight. Under the normal straightforward, plain vanilla, VFR that the question appears to relate to, the pilot is entirely responsible for avoiding collisions with the ground or anything else. (Please don't ask about the other flavours of VFR!).
In the past I have known some units and individual controllers that have routinely issues clearances that cannot be complied with (at least, not without breaking some rule or other or applying a very liberal intepretation) but this seems far less common these days.
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JR - I agree with your attitude entirely.
As to the original incident in question, I can think of only a couple of reasons why a pilot would be given a potentially unsafe (albeit VFR) clearance - don't forget, as reported this wasn't a 'cleared to descend....' but 'cleared not above.....'. Whilst those two differents phraseologies have very different meanings in ATC terms, as a (low-experience) pilot may see it, one is an offer, while one is an obligation to descend. It is much harder (from a human factors pov) to refuse an instruction than an offer (That said, one of the criteria for holding a pilot's licence must be that one is capable to doing both, where either conflict with safety of the aircraft).
However, there lies the trap for the unwary. Even though all involved are abiding by their respective responsibilities, both in safety and commercial terms (i.e. endeavouring to allow zone access, rather than restricting it), someone has highlighted a way in which the overall level of care provided by ATC (and in the UK, that is exceptionally high to begin with) could be improved -even if it is only in certain limited circumstances, and even if it may result in delays for those wishing to transit CAS in and around terrain.
How about: "G-CD, are you able to remain clear of terrain below 2000' on the RPS?" first, before the clearance is given to that effect? Or something similar.
That may take up a bit more RT, but so does "Negative Manchester, cannot accept that clearance due terrain, request blah blah"
Even if it just makes ATCOs think about the implict safety implications of imposing altitude restrictions in the region of high ground, Jump Complete makes an important comment - one I might humbly suggest is exactly the kind of thing CHIRP was invented for.
As to the original incident in question, I can think of only a couple of reasons why a pilot would be given a potentially unsafe (albeit VFR) clearance - don't forget, as reported this wasn't a 'cleared to descend....' but 'cleared not above.....'. Whilst those two differents phraseologies have very different meanings in ATC terms, as a (low-experience) pilot may see it, one is an offer, while one is an obligation to descend. It is much harder (from a human factors pov) to refuse an instruction than an offer (That said, one of the criteria for holding a pilot's licence must be that one is capable to doing both, where either conflict with safety of the aircraft).
However, there lies the trap for the unwary. Even though all involved are abiding by their respective responsibilities, both in safety and commercial terms (i.e. endeavouring to allow zone access, rather than restricting it), someone has highlighted a way in which the overall level of care provided by ATC (and in the UK, that is exceptionally high to begin with) could be improved -even if it is only in certain limited circumstances, and even if it may result in delays for those wishing to transit CAS in and around terrain.
How about: "G-CD, are you able to remain clear of terrain below 2000' on the RPS?" first, before the clearance is given to that effect? Or something similar.
That may take up a bit more RT, but so does "Negative Manchester, cannot accept that clearance due terrain, request blah blah"
Even if it just makes ATCOs think about the implict safety implications of imposing altitude restrictions in the region of high ground, Jump Complete makes an important comment - one I might humbly suggest is exactly the kind of thing CHIRP was invented for.
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You said you were flying VFR.
VFR by Law means clear of cloud and in sight of the surface.
You are also required by law to avoid other aircraft on the see and avoid principle and in addition you are responsible for your own terrain seperation. It follows that if ATC clear you through controlled airspace at a certain level it is YOUR responsibility for terrain and traffic seperation.
Even flying IFR never trust a clearance always always check that the cleared level is safe.
The fact that the FAA advise all American crews flying IFR never to assume that a cleared level in the UK is safe is an interesting point.
I say keep all departures and arrivals procedural. That way we only have ourselves to blame.
I also think that the UK ATC is the best in the world. When I arrive back to UK airspace and call London after a 12 hour flight I know I am safe and sound. 20 years of commercial flying I still say them words "Good morning London, speedbird 068, FL 390 direct strumble" with pride and passion to those guys that keep us safe everyday we take to the sky.
VFR by Law means clear of cloud and in sight of the surface.
You are also required by law to avoid other aircraft on the see and avoid principle and in addition you are responsible for your own terrain seperation. It follows that if ATC clear you through controlled airspace at a certain level it is YOUR responsibility for terrain and traffic seperation.
Even flying IFR never trust a clearance always always check that the cleared level is safe.
The fact that the FAA advise all American crews flying IFR never to assume that a cleared level in the UK is safe is an interesting point.
I say keep all departures and arrivals procedural. That way we only have ourselves to blame.
I also think that the UK ATC is the best in the world. When I arrive back to UK airspace and call London after a 12 hour flight I know I am safe and sound. 20 years of commercial flying I still say them words "Good morning London, speedbird 068, FL 390 direct strumble" with pride and passion to those guys that keep us safe everyday we take to the sky.
Thread Starter
Thank you for your replies. I think though, that people have misunderstood the point of my post.
Firstly, regarding the clearance I recieved, it was "Cleared to enter not above 2000' " That to me is a definete instruction, not an invitation to descend
when I felt like it. I could not safely have carried out that instruction.
Regarding the high ground, the peak was around 2100' but the lower ground (the lowest around) was about 1900') Doglegging wasn't an option.
As I stated, I fully appreciate that it is the PICs responsibility for terrain clearance. No aurgument there. If I had hit high ground, regardless of the weather it would have been my own stupidity.
However, suppose the visability had been poor (but still VFR) the pilot was under pressure for what ever reason, with situational awarenes reduced from optimum. On recieving that clearance I decide to descend to be below 2000' by 5 miles before the zone boundry, to be sure. I would then have been in a potential CFIT situation.
My own expereince, qualifications or what sort of flight I was doing isn't particually relevent to the discusion. I didn't have a problem because I could see the problem and did something about it. Accidents are a chain and something like that is a pretty big one.
Having said that, I fully agree that ATC is first class and do a fantastic job. Im simply asking people to recognise that a situtaion like this has a potential safety implication.
Firstly, regarding the clearance I recieved, it was "Cleared to enter not above 2000' " That to me is a definete instruction, not an invitation to descend
when I felt like it. I could not safely have carried out that instruction.
Regarding the high ground, the peak was around 2100' but the lower ground (the lowest around) was about 1900') Doglegging wasn't an option.
As I stated, I fully appreciate that it is the PICs responsibility for terrain clearance. No aurgument there. If I had hit high ground, regardless of the weather it would have been my own stupidity.
However, suppose the visability had been poor (but still VFR) the pilot was under pressure for what ever reason, with situational awarenes reduced from optimum. On recieving that clearance I decide to descend to be below 2000' by 5 miles before the zone boundry, to be sure. I would then have been in a potential CFIT situation.
My own expereince, qualifications or what sort of flight I was doing isn't particually relevent to the discusion. I didn't have a problem because I could see the problem and did something about it. Accidents are a chain and something like that is a pretty big one.
Having said that, I fully agree that ATC is first class and do a fantastic job. Im simply asking people to recognise that a situtaion like this has a potential safety implication.