Chinook - Still Hitting Back 3 (Merged)
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I say again; the MOD have stated the negligent act occured BEFORE waypoint change.
If the geographical location of this act is not identified then the existance of gross negligence, from that location, cannot be substantiated.
So exactly WHERE did the crew fail in their duty of care?
If the geographical location of this act is not identified then the existance of gross negligence, from that location, cannot be substantiated.
So exactly WHERE did the crew fail in their duty of care?
Just a numbered other
Walter,
OK I'm Navy and not RAF, but I thought I'd given you a few hints. It isn't sloppy to put a waypoint of 'roughly' the Mull light house in the TANS. The flight is VFR, and all you want is to be pointed at the Mull, which you'll identify visually, change waypoint and fly on to the next, along the coast.
It would never be one's intention to actually overfly the waypoint and straight line it to the next.
Their 'intended flight plan' died with them, as it would be constantly updated as the trip progressed.
As for a portable TACAN, I'm 99.9% certain they would not have use of such. Whay would they go to all that expence and bother?
It was a VFR flight. There is no proof that at any time they intentionally lost VMC and elected to continue IFR.
Why they crashed is, and will remain, unclear. They have not been found to be negligent to the required standard. They should be cleared. NOW.
Oh, and psyclic, if you listen to people like K52, they were negligent because they didn't have time for breakfast. Clutching at straws, or what!
OK I'm Navy and not RAF, but I thought I'd given you a few hints. It isn't sloppy to put a waypoint of 'roughly' the Mull light house in the TANS. The flight is VFR, and all you want is to be pointed at the Mull, which you'll identify visually, change waypoint and fly on to the next, along the coast.
It would never be one's intention to actually overfly the waypoint and straight line it to the next.
Their 'intended flight plan' died with them, as it would be constantly updated as the trip progressed.
As for a portable TACAN, I'm 99.9% certain they would not have use of such. Whay would they go to all that expence and bother?
It was a VFR flight. There is no proof that at any time they intentionally lost VMC and elected to continue IFR.
Why they crashed is, and will remain, unclear. They have not been found to be negligent to the required standard. They should be cleared. NOW.
Oh, and psyclic, if you listen to people like K52, they were negligent because they didn't have time for breakfast. Clutching at straws, or what!
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Arkroyal
I never believed them to be sloppy - I referred to the tone of some of the comments in the inquiries; eg
1034. …Sir John. The point which you have marked, the Waypoint…….was the lighthouse 0.81 nautical miles away,…..?
(Sir John Day) I can remember the details, my Lord. The point that they had plotted as the lighthouse, which was actually incorrect, if you recall, so the computer, and presumably they, both thought that Waypoint Alpha was the position of the lighthouse, as it turns out, we now know that they had slightly misplotted it.
To me, someone should have pointed out the actual feature that was used.
Regards portable TACAN - you may find it interesting to look up "PRC-112" type equipments - to see how small they are, that they have the ability to be used as portable DMEs (only weigh 28 ounces) and the uses of them, particularly for marking isolated navigation hazards near landing zones in operational areas.
ZD576s IFF system was set to mode 3a which interrogates any such set in range - giving a very accurate range.
My big point now is that, there was no mention of this embedded (in the IFF system) navigation aid that was available to them (and the on board equipment set appropriately) in the inquiries - yet every other thing was thoroughly gone over.
I never believed them to be sloppy - I referred to the tone of some of the comments in the inquiries; eg
1034. …Sir John. The point which you have marked, the Waypoint…….was the lighthouse 0.81 nautical miles away,…..?
(Sir John Day) I can remember the details, my Lord. The point that they had plotted as the lighthouse, which was actually incorrect, if you recall, so the computer, and presumably they, both thought that Waypoint Alpha was the position of the lighthouse, as it turns out, we now know that they had slightly misplotted it.
To me, someone should have pointed out the actual feature that was used.
Regards portable TACAN - you may find it interesting to look up "PRC-112" type equipments - to see how small they are, that they have the ability to be used as portable DMEs (only weigh 28 ounces) and the uses of them, particularly for marking isolated navigation hazards near landing zones in operational areas.
ZD576s IFF system was set to mode 3a which interrogates any such set in range - giving a very accurate range.
My big point now is that, there was no mention of this embedded (in the IFF system) navigation aid that was available to them (and the on board equipment set appropriately) in the inquiries - yet every other thing was thoroughly gone over.
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Using IFF for Range
I have entered into a series of PMs with Walter about this subject and he seems convinced that the crew of ZD576 may have been using an IFF mode to get range from a portable beacon placed at or near the planned turning point at the end of the Mull. Seems most unlikely (bordering on the fantastic!) to me, but I'm a fast-jet man, not a Chinook man, so is there a Chinook man out there who can address his concern?
He, like AM Day, thinks that the turn (of 7 degrees), 'belly up' to the coast would have been difficult to judge, meaning they were negligent. Walter's solution is that they must've been using some kind of DME, which proved to be eroneous, somehow causing the crash. My thought is that, even if an IFF DME range were available, there would be little or no use for the information and the pilots would have turned using straightforward visual range cues and that Day's negligence claim based on this is (I'll remain polite) erroneous. Perhaps, whilst you're about it, you (Chinook man) could suggest an angle of bank and length of time for a 7-degree turn - my estimate would be 15 deg bank for 5 secs.
He, like AM Day, thinks that the turn (of 7 degrees), 'belly up' to the coast would have been difficult to judge, meaning they were negligent. Walter's solution is that they must've been using some kind of DME, which proved to be eroneous, somehow causing the crash. My thought is that, even if an IFF DME range were available, there would be little or no use for the information and the pilots would have turned using straightforward visual range cues and that Day's negligence claim based on this is (I'll remain polite) erroneous. Perhaps, whilst you're about it, you (Chinook man) could suggest an angle of bank and length of time for a 7-degree turn - my estimate would be 15 deg bank for 5 secs.
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MEADOWBANK
Where the hell did you get this from?????
<<He, like AM Day, thinks that the turn (of 7 degrees), 'belly up' to the coast would have been difficult to judge, meaning they were negligent. >>
I have never, ever implied that they were negligent the "belly up" quote came from the inquiry, not me. How dare you put me in the same camp as Day - you have wilfully trivialised the navigation scenario that I have been trying to put.
Your puerile tone and sarcasm is sadly so typical as I have received from your kind - I have had to take it on the chin as I need to repeat the call regularly for people to come forward with the crucial information to close off (one way or other) this as yet not fully explored possibilty and so am exposed to the likes of you - if you have nothing positive to contribute, then occupy yourself someplace else, you are wasting space.
I believe also that there is something wrong about (mis) quoting pms the way you did on the forum - there has to be some standard of behaviour - if I were to sink to your level, I could always post your last message ....
Where the hell did you get this from?????
<<He, like AM Day, thinks that the turn (of 7 degrees), 'belly up' to the coast would have been difficult to judge, meaning they were negligent. >>
I have never, ever implied that they were negligent the "belly up" quote came from the inquiry, not me. How dare you put me in the same camp as Day - you have wilfully trivialised the navigation scenario that I have been trying to put.
Your puerile tone and sarcasm is sadly so typical as I have received from your kind - I have had to take it on the chin as I need to repeat the call regularly for people to come forward with the crucial information to close off (one way or other) this as yet not fully explored possibilty and so am exposed to the likes of you - if you have nothing positive to contribute, then occupy yourself someplace else, you are wasting space.
I believe also that there is something wrong about (mis) quoting pms the way you did on the forum - there has to be some standard of behaviour - if I were to sink to your level, I could always post your last message ....
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meadowbank it is considered unfair by many that that which is contained in a PM is used in open forum against the person who wrote it. Private Messages are what they are. If the writer wanted to place it on the forum he would have done so. All you have done is revealed that you never learned cricket - or anything that taught you fair play. An apology would not be out of place wouldn't you say.
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WALTER
Your messages, both open and PM, had given me the distinct impression that you considered that the crew of ZD576 had carried out a dangerous manoeuvre, and I expended considerable time and effort trying to explain why I felt that this was not the case and why I thought your suggestion that the crew were using a range readout from portable DME or IFF equipment at or near the lighthouse extremely unlikely. My post, perhaps somewhat ill-considered, was an attempt to muster expert opinion on this particular aspect. I wanted to get, to use your own words, "people to come forward with the crucial information" that would kill off the idea that they may have been using DME of some kind to judge their turn.
I did not quote you or AM Day - belly up is a perfectly normal phrase used by all in aviation to describe an aircraft banking away from something, but which the layman may not recognise. I put it into parenthesis to indicate that rather than in speech marks to indicate a quote. That I linked you with Day is because that is where your argument seemed to be placing you; it was my subjective view.
I apologise for ruffling your feathers, but your personal attack is both distasteful and unwarranted.
MODERATOR
I apologise if I have inadvertently broken a convention, but, having rechecked the info on Pprune about PMs, there is nothing to indicate that their content should not be revealed or their content referred to. Indeed, the phrase you have used is that "it is considered unfair by many......". I see a PM as being no different to a telephone call with what is, after all, a stranger.
I find your comments about cricket and fair play unreasonable, given that the rules for PMs don't appear to be written down anywhere. It may be your job to moderate posts and to point out the appropriate etiquette, but this should not extend to making patronising comments.
Your messages, both open and PM, had given me the distinct impression that you considered that the crew of ZD576 had carried out a dangerous manoeuvre, and I expended considerable time and effort trying to explain why I felt that this was not the case and why I thought your suggestion that the crew were using a range readout from portable DME or IFF equipment at or near the lighthouse extremely unlikely. My post, perhaps somewhat ill-considered, was an attempt to muster expert opinion on this particular aspect. I wanted to get, to use your own words, "people to come forward with the crucial information" that would kill off the idea that they may have been using DME of some kind to judge their turn.
I did not quote you or AM Day - belly up is a perfectly normal phrase used by all in aviation to describe an aircraft banking away from something, but which the layman may not recognise. I put it into parenthesis to indicate that rather than in speech marks to indicate a quote. That I linked you with Day is because that is where your argument seemed to be placing you; it was my subjective view.
I apologise for ruffling your feathers, but your personal attack is both distasteful and unwarranted.
MODERATOR
I apologise if I have inadvertently broken a convention, but, having rechecked the info on Pprune about PMs, there is nothing to indicate that their content should not be revealed or their content referred to. Indeed, the phrase you have used is that "it is considered unfair by many......". I see a PM as being no different to a telephone call with what is, after all, a stranger.
I find your comments about cricket and fair play unreasonable, given that the rules for PMs don't appear to be written down anywhere. It may be your job to moderate posts and to point out the appropriate etiquette, but this should not extend to making patronising comments.
Just a numbered other
Not a 'chinook boy' but can ANYONE tell me how IFF can be used for range???
I've said this before, but if the crew were using ANYTHING other than the Mk 1 eyeball for terrain separation, they were indeed negligent.
I don't beleive that thay were.
I've said this before, but if the crew were using ANYTHING other than the Mk 1 eyeball for terrain separation, they were indeed negligent.
I don't beleive that thay were.
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CarltonBrowne the FO
Because the Macrihanish TACAN was not LOS (Line of Sight) to the Chinook on this leg and therefore unusable.
Arkroyal
Most people think of DME in terms of the co-located VOR/DME (civil) or TACAN (mil) ground equipment – the big array is for the VOR, the DME does not require a big array and, with modern electronics, the ground transponder of a DME system can be incorporated into a hand held communicator such as for example the PRC-112 (tens of thousands of equivalent units have been manufactured for the US alone).
Most people think of an IFF system as an aircraft transponder which, when interrogated by a signal from another aircraft or ATC ground equipment, replies with a coded signal giving information on the type of flight, the aircrafts altitude, etc, but many modern airborne IFF equipments (such as for example the AN/ARS-6) have the ability (when selected in the right mode, “3a”) to interrogate any of the portable types (eg as above) within LOS range, giving an accurate range to such units.
These are typically fitted in SAR and Support Helicopters (SH) for the purposes of (I name but a few – not my imagination but extracted from manufacturers blurb:
Location of downed aircrew;
Location of special forces elements for re-supply or extraction;
Marking of isolated navigation hazards in operational areas …..
Why not just GPS, I hear you say? – in case GPS is jammed/ DME is relative and accurate/ it only transmits when correctly interrogated thus remaining covert as much as possible, etc..
You say:
<<I've said this before, but if the crew were using ANYTHING other than the Mk 1 eyeball for terrain separation, they were indeed negligent.>>
With respect, this is the simplistic VFR vs IFR argument - I have tried my best in past postings to explain the scenario where, in such common conditions that prevailed at the Mull, a special arrangement MAY have been accepted to help helicopters (suitably equipped and with trained crew as was the case in ZD576) in this one awkward turn that would otherwise have complicated a walk-in-the-park/pleasant low level VFR flight on a regularly used leg.
And:
<<I don't beleive that thay were.>>
I say that this is a moot point at this stage as the existence of such a system to the crew should have been mentioned at the inquiries. Further, that mode 3a WAS selected strongly suggests that they were using it. Confirmation of the squawk code as allocated by ATC Aldergrove, or as detected by them (Aldergrove ATC had been tracking them and so would have been able to confirm the code that they had set PRIOR to the impact) could settle this issue once and for all – for example, in some regions 7760 specifically alerts ATC or other a/c that the aircraft in question is working off such a ground transponder in local operations such as SAR exercises.
It is of note that queries at the Lords inquiry on the meaning of the squawk code were answered in generalizations – it would seem rational for the squawk code apparently (to ATC) used to have been stated.
The crew should not be held negligent if this was an accepted practice for such flights on this leg unless the ground equipment was known to be secure, unaltered, and in its correct location at the time (and these factors should have been covered in the inquiries if such a system was used).
My initial interest in this case (10 years ago) was to remind authorities to check these factors before evidence to the contrary was lost – not to push it as THE cause but the checking could not wait while the rest of the investigations continued.
THAT TURN
Let me try and explain better.
If you were flying VFR at low level over water or a featureless patch of desert, you would glance regularly at your altimeter for reassurance, surely? – a basic, trusted instrument, the altimeter. Now, if you were descending to low level over such terrain (VFR still), you would trust your altimeter over your visual judgment – as you approached the (featureless) ground you would refer to your altimeter to support your judgment of the right moment to level out?
The Mull in those conditions would have been a grey, featureless, irregular surface which was being approached at high speed and it was desired to make a turn up the coast close in; imagine if a crew member was watching a nice digital reading of range to go on a trusted system – he could even have been counting it down for the pilot; how strongly would this influence the pilot’s visual judgment?
No matter that the judgment should only have been visual, think of the influence of that countdown in his interpretation of what he sees.
And what if the ground transponder had been moved/substituted/altered etc.?
Because the Macrihanish TACAN was not LOS (Line of Sight) to the Chinook on this leg and therefore unusable.
Arkroyal
Most people think of DME in terms of the co-located VOR/DME (civil) or TACAN (mil) ground equipment – the big array is for the VOR, the DME does not require a big array and, with modern electronics, the ground transponder of a DME system can be incorporated into a hand held communicator such as for example the PRC-112 (tens of thousands of equivalent units have been manufactured for the US alone).
Most people think of an IFF system as an aircraft transponder which, when interrogated by a signal from another aircraft or ATC ground equipment, replies with a coded signal giving information on the type of flight, the aircrafts altitude, etc, but many modern airborne IFF equipments (such as for example the AN/ARS-6) have the ability (when selected in the right mode, “3a”) to interrogate any of the portable types (eg as above) within LOS range, giving an accurate range to such units.
These are typically fitted in SAR and Support Helicopters (SH) for the purposes of (I name but a few – not my imagination but extracted from manufacturers blurb:
Location of downed aircrew;
Location of special forces elements for re-supply or extraction;
Marking of isolated navigation hazards in operational areas …..
Why not just GPS, I hear you say? – in case GPS is jammed/ DME is relative and accurate/ it only transmits when correctly interrogated thus remaining covert as much as possible, etc..
You say:
<<I've said this before, but if the crew were using ANYTHING other than the Mk 1 eyeball for terrain separation, they were indeed negligent.>>
With respect, this is the simplistic VFR vs IFR argument - I have tried my best in past postings to explain the scenario where, in such common conditions that prevailed at the Mull, a special arrangement MAY have been accepted to help helicopters (suitably equipped and with trained crew as was the case in ZD576) in this one awkward turn that would otherwise have complicated a walk-in-the-park/pleasant low level VFR flight on a regularly used leg.
And:
<<I don't beleive that thay were.>>
I say that this is a moot point at this stage as the existence of such a system to the crew should have been mentioned at the inquiries. Further, that mode 3a WAS selected strongly suggests that they were using it. Confirmation of the squawk code as allocated by ATC Aldergrove, or as detected by them (Aldergrove ATC had been tracking them and so would have been able to confirm the code that they had set PRIOR to the impact) could settle this issue once and for all – for example, in some regions 7760 specifically alerts ATC or other a/c that the aircraft in question is working off such a ground transponder in local operations such as SAR exercises.
It is of note that queries at the Lords inquiry on the meaning of the squawk code were answered in generalizations – it would seem rational for the squawk code apparently (to ATC) used to have been stated.
The crew should not be held negligent if this was an accepted practice for such flights on this leg unless the ground equipment was known to be secure, unaltered, and in its correct location at the time (and these factors should have been covered in the inquiries if such a system was used).
My initial interest in this case (10 years ago) was to remind authorities to check these factors before evidence to the contrary was lost – not to push it as THE cause but the checking could not wait while the rest of the investigations continued.
THAT TURN
Let me try and explain better.
If you were flying VFR at low level over water or a featureless patch of desert, you would glance regularly at your altimeter for reassurance, surely? – a basic, trusted instrument, the altimeter. Now, if you were descending to low level over such terrain (VFR still), you would trust your altimeter over your visual judgment – as you approached the (featureless) ground you would refer to your altimeter to support your judgment of the right moment to level out?
The Mull in those conditions would have been a grey, featureless, irregular surface which was being approached at high speed and it was desired to make a turn up the coast close in; imagine if a crew member was watching a nice digital reading of range to go on a trusted system – he could even have been counting it down for the pilot; how strongly would this influence the pilot’s visual judgment?
No matter that the judgment should only have been visual, think of the influence of that countdown in his interpretation of what he sees.
And what if the ground transponder had been moved/substituted/altered etc.?
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Walter
You wrote "a special arrangement MAY have been accepted to help helicopters (suitably equipped and with trained crew as was the case in ZD576) in this one awkward turn that would otherwise have complicated a walk-in-the-park/pleasant low level VFR flight on a regularly used leg."
There is nothing awkward about this turn so no special arrangement would be necessary. It is the kind of turn made every day by helicopters (and fixed-wing aircraft) on low-altitude flights. Indeed, this appears to have been a "regularly used leg" (your words) - hardly a likely situation if there was any extra element of risk involved.
Mode 3/A is the standard ATC mode used by all military and civilian transponders. I don't know about the sets fitted to Chinooks, but on some military IFF sets, having the first 2 digits set to 77, irrespective of the settings of the 3rd and 4th digits, identifies to ATC as an emergency squawk. This could have been the intention of one of the crew, indicating that some form of emergency had occurred.
SuperTANS incorporates GPS positioning so why bother with a separate system that, you tell us, gives a range-only readout? Tandemrotor (a Chinook operator) has not heard of the system you describe so it seems unlikely that it's fitted.
THAT TURN
The altimeter is only as accurate as the Regional Pressure Setting (RPS) that is set on its subscale. The RPS is forecast by the National Met Office (nr London) and is notoriously unreliable. This flight was carried out entirely within the Belfast Altimeter Setting Region and the same RPS is used all over it, even though the actual pressure could vary by several millibars within this area - the altimeter is therefore not to be trusted.
The crew had no need to descend over the terrain you have described as they were over the sea at the point at whch the decision was apparently made to turn towards the next turning point. The ground is not featureless - it includes one of the best features available, a coastline. The countdown you have described is not part of Standard Operating Procedures. IF the portable IFF that you have described exists, the fact that it might not be in the position at which you believe it to be is a very good reason not to trust it in the way that you suggest. I believe that your suggestion can therefore be discounted.
You wrote "a special arrangement MAY have been accepted to help helicopters (suitably equipped and with trained crew as was the case in ZD576) in this one awkward turn that would otherwise have complicated a walk-in-the-park/pleasant low level VFR flight on a regularly used leg."
There is nothing awkward about this turn so no special arrangement would be necessary. It is the kind of turn made every day by helicopters (and fixed-wing aircraft) on low-altitude flights. Indeed, this appears to have been a "regularly used leg" (your words) - hardly a likely situation if there was any extra element of risk involved.
Mode 3/A is the standard ATC mode used by all military and civilian transponders. I don't know about the sets fitted to Chinooks, but on some military IFF sets, having the first 2 digits set to 77, irrespective of the settings of the 3rd and 4th digits, identifies to ATC as an emergency squawk. This could have been the intention of one of the crew, indicating that some form of emergency had occurred.
SuperTANS incorporates GPS positioning so why bother with a separate system that, you tell us, gives a range-only readout? Tandemrotor (a Chinook operator) has not heard of the system you describe so it seems unlikely that it's fitted.
THAT TURN
The altimeter is only as accurate as the Regional Pressure Setting (RPS) that is set on its subscale. The RPS is forecast by the National Met Office (nr London) and is notoriously unreliable. This flight was carried out entirely within the Belfast Altimeter Setting Region and the same RPS is used all over it, even though the actual pressure could vary by several millibars within this area - the altimeter is therefore not to be trusted.
The crew had no need to descend over the terrain you have described as they were over the sea at the point at whch the decision was apparently made to turn towards the next turning point. The ground is not featureless - it includes one of the best features available, a coastline. The countdown you have described is not part of Standard Operating Procedures. IF the portable IFF that you have described exists, the fact that it might not be in the position at which you believe it to be is a very good reason not to trust it in the way that you suggest. I believe that your suggestion can therefore be discounted.
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I have been involved with the problems of the Mk 2 since well before this accident and I have vigorously supported the search for justice ever since. I have flown the Chinook and a number of other military helicopter types. I have read and occasionally contributed to this forum over the better part of a year. And, I have never seen such an extraordinary amount of time and effort wasted than in this bizarre debate about the phantom, mobile DME. Perhaps we should move on to little green men shining lasers at the crew to distract them ?
Let's face it; there are much more plausible contributory factors to be found in the known state of that aircraft during the 60 hours leading to the accident. However, the conduct of the BoI included a deliberate process designed to make sure that those who looked at the evidence were kept away from those who knew about the aircraft and its history.
Wasting time inventing obviously ludicrous scenarios is not helpful. I doubt I will be able to persuade Walter to drop this search for someone who will own up to being a Chinook pilot who is aware of a great conspiracy to place little DMEs all over the countryside. I also flew Pumas and even a Puma pilot could do without such a thing !
Please drop it and let's get back to putting pressure on the MOD to give the crew some justice.
Let's face it; there are much more plausible contributory factors to be found in the known state of that aircraft during the 60 hours leading to the accident. However, the conduct of the BoI included a deliberate process designed to make sure that those who looked at the evidence were kept away from those who knew about the aircraft and its history.
Wasting time inventing obviously ludicrous scenarios is not helpful. I doubt I will be able to persuade Walter to drop this search for someone who will own up to being a Chinook pilot who is aware of a great conspiracy to place little DMEs all over the countryside. I also flew Pumas and even a Puma pilot could do without such a thing !
Please drop it and let's get back to putting pressure on the MOD to give the crew some justice.
Machrihanish used to have a TACAN, there was a VOR-only civil navigation beacon nearby. Later, when the aerodrome closed, the Machrihanish TACAN was removed and the VOR became a VOR/DME using the same DME frequency as had the previous TACAN.
If someone was using Machrihanish VOR/DME ranges assuming that they were actually coming from the Machrihanish TACAN, they would not be where they thought they were.
All of which is probably irrelevant to this accident whose cause, except in the blinkered views of Wratten, Day and Hoon is still not positively determined.
If someone was using Machrihanish VOR/DME ranges assuming that they were actually coming from the Machrihanish TACAN, they would not be where they thought they were.
All of which is probably irrelevant to this accident whose cause, except in the blinkered views of Wratten, Day and Hoon is still not positively determined.
A really irritating PPRuNer
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Hi Everyone,
sorry for the short period of silence (although some may say it has been a blessing!). Took a few weeks out on a battery-charging deployment to a seaside resort of Mrs Dixon's choosing.
I took along the book mentioned by WOrkER - Chinook Crash by Steuart Campbell, as a little light reading (My wife doesn't think I have a life either!
. The book can be reviewed in three words - Disappointing and misleading. There are speculations presented as fact (where have we heard that before?), inaccuracies and selective quotation to fit nothing more than an individual's theory.
The author claims to be "Well qualified to analyse the Chinook disaster" yet doesn't list his qualifications. If they are merely reading loads of documents on the subject, then I will, arrogantly, claim to match those qualifications, and stand by my review of his book. A thorough, and better evidenced review is currently being compiled and will be posted once it is ready, although I don't wish to turn this thread into a 'critique thread'. The book is a publication of a individual's opinion, presented with as much conviction as my own views. I have no problem with that. I just don't think it is the 'definitive answer' it claims to be.
Despite recent events with regard the meeting between Mr Arbuthnot MP and the Prime Minister, the campaign continues with as much determination as before.
PPRuNe Pop,
many thanks for merging the threads, but I have to agree with those that have posted their views already. Whilst it shows Hoon's true colours with regard this injustice, it may take the discussion off on a side track that is of little benefit. Please don't think I'm being rude, or ungrateful as I'm not. Those in the media may find his inappropriate humour worthy of comment though.
Updates, as and when.
My best to all.
Brian
"Justice has no expiry date" - John Cook
sorry for the short period of silence (although some may say it has been a blessing!). Took a few weeks out on a battery-charging deployment to a seaside resort of Mrs Dixon's choosing.
I took along the book mentioned by WOrkER - Chinook Crash by Steuart Campbell, as a little light reading (My wife doesn't think I have a life either!
. The book can be reviewed in three words - Disappointing and misleading. There are speculations presented as fact (where have we heard that before?), inaccuracies and selective quotation to fit nothing more than an individual's theory.The author claims to be "Well qualified to analyse the Chinook disaster" yet doesn't list his qualifications. If they are merely reading loads of documents on the subject, then I will, arrogantly, claim to match those qualifications, and stand by my review of his book. A thorough, and better evidenced review is currently being compiled and will be posted once it is ready, although I don't wish to turn this thread into a 'critique thread'. The book is a publication of a individual's opinion, presented with as much conviction as my own views. I have no problem with that. I just don't think it is the 'definitive answer' it claims to be.
Despite recent events with regard the meeting between Mr Arbuthnot MP and the Prime Minister, the campaign continues with as much determination as before.
PPRuNe Pop,
many thanks for merging the threads, but I have to agree with those that have posted their views already. Whilst it shows Hoon's true colours with regard this injustice, it may take the discussion off on a side track that is of little benefit. Please don't think I'm being rude, or ungrateful as I'm not. Those in the media may find his inappropriate humour worthy of comment though.
Updates, as and when.
My best to all.
Brian
"Justice has no expiry date" - John Cook
Last edited by Brian Dixon; 5th Sep 2004 at 15:53.
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Oi! Dixon! You sneaky devil! Where's my stick of Blackpool rock? Fancy taking time out for a HOLIDAY! [Let me seen now; holiday, er, um, oh yes - that's the thing where your boss lets you off work for a little time and still pays you, isn't it?]
Seriously, Brian, glad you had a break - God knows, the amount of effort you have poured into the Campaign over the years earns you special privileges that belong to no-one else on this thread.
I am sure I can safely speak for the vast majority in hoping that you had good time with your Good Lady.
BTW, thanks for the heads up on saving money on the book you reviewed - keep us updated on the review currently under compilation; sounds like a better bet - I'll buy any publications that you recommend, since your Peers on PPrune recognise that you are effectively the authority on the the subject.
FJJP
Seriously, Brian, glad you had a break - God knows, the amount of effort you have poured into the Campaign over the years earns you special privileges that belong to no-one else on this thread.
I am sure I can safely speak for the vast majority in hoping that you had good time with your Good Lady.
BTW, thanks for the heads up on saving money on the book you reviewed - keep us updated on the review currently under compilation; sounds like a better bet - I'll buy any publications that you recommend, since your Peers on PPrune recognise that you are effectively the authority on the the subject.
FJJP
A really irritating PPRuNer
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FJJP,sincere apologies for not bringing back said rock. But to be fair, I would have had to have brought back about 1000 sticks so that everyone would have got one.
Break was excellent, thank you.
I'm flattered by your description of me being an authority. There are far more people out there who know as much, if not more than I. I've said it before - My notoriety is simply because I shoot my mouth off on PPRuNe! Plus, of course, I'm extremely irritating!
PPRuNe Pop,
no apologies necessary. I certainly didn't take any offence, and I would like to publically state my personal thanks to you and your colleagues at PPRuNe Towers for your continued support.
My best (and thanks) as always,
Brian
"Justice has no expiry date" - John Cook
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Brian, just be flattered!
Someone who is as willing as you to spend so much of you own precious time in such a worthy cause deserve just recognition. One worthy campaigner with a square head on shoulders who can cut through the cr*p without bucket-loads of emotive terminology is worth a dozen 'experts' Your have brought the whole saga together in a cohesive fashion that allows the rest of us semi-literates [well, me, anyway] to gain a real understanding of the arguments.
Your efforts are well appreciated; thank you...
FJJP
PS, PPP, thanks for the split... now we can get on with some real pratt bashing in a separate locale!
Someone who is as willing as you to spend so much of you own precious time in such a worthy cause deserve just recognition. One worthy campaigner with a square head on shoulders who can cut through the cr*p without bucket-loads of emotive terminology is worth a dozen 'experts' Your have brought the whole saga together in a cohesive fashion that allows the rest of us semi-literates [well, me, anyway] to gain a real understanding of the arguments.
Your efforts are well appreciated; thank you...
FJJP
PS, PPP, thanks for the split... now we can get on with some real pratt bashing in a separate locale!
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Meadowbank
Look at the picture posted by Tarnished 1st September on Mil Aircrew thread entitled
“Typhoons and Reds” .
Apart from being a great shot, look at the mist on the other side of the water – readers not so familiar with localized coastal mist like on the Mull that day can get an idea of the problem using this picture and a bit of imagination, thus:
imagine the middle bit extending across the whole field of view (put your hands over each side to mask the shoreline);
use some tape to mask the aircraft and that one wave;
imagine the top disappears into the cloud base of the same colour;
then you would have the kind of view that would commonly confront crews approaching from NI on the leg to the Mull lighthouse – see the difference?
Common sense dictates that you would have to stay well clear if relying on visual judgment alone – you wrote:
<<There is nothing awkward about this turn so no special arrangement would be necessary. It is the kind of turn made every day by helicopters (and fixed-wing aircraft) on low-altitude flights. Indeed, this appears to have been a "regularly used leg" (your words) - hardly a likely situation if there was any extra element of risk involved.>>
I believe that it was a regular thing to turn in close as described to me by a witness who had reason to know – and while talking to him near the crash site in identical weather conditions one did just that. I believe that it was risky to have approached closer than, say, the waypoint change in these conditions unless they had something else to go on, never mind aiming to turn right on the coastline.
You wrote:
<<Mode 3/A is the standard ATC mode used by all military and civilian transponders.>>
Yes, I apologize for getting confused with some technical information on a commercial (private) system that does it all – in an HC2 (i.e. MK2 equivalent to CH47-D), a separate interrogator is plugged into the (AN-ARC 164) radio (as is fitted to the MK2 Chinook) – mode 3a is significant here only in that it was the correct mode to squawk a code describing the activity of the aircraft. The (US, don’t know NATO at moment) NSN # of such an interrogator is 5895-01-494-5228.
And:
<< I don't know about the sets fitted to Chinooks, but on some military IFF sets, having the first 2 digits set to 77, irrespective of the settings of the 3rd and 4th digits, identifies to ATC as an emergency squawk.>>
Not so:
There are many international references to squawk codes (including one I have found specific on 7760 being associated with ground transponders) but what the UK military uses would be classified and so I cannot myself absolutely confirm the meaning of 7760 to this flight – it would be nice if someone who could would come forward.
Just to counter your broad dismissal that anything starting 77** means an emergency squawk, I can quickly grab this reference:
<<ICAO CAL Edition 2
Supplement to EUR ANP FASID May 2003
Code 7776 and Code 7777 are reserved for SSR ground transponder
monitoring.>> - please note the first 2 digits are “77”.
Another that suggests that 7760 has an interesting meaning is:
<< RRR 7750-7799 ANDOVER RAF SPECIAL TASKS>>
If Boscombe Down had wanted to evaluate a new NavAid on the Mull and had sent its old workhorse up there, it would have been entirely appropriate for that aircraft to have been squawking 7760 (I think it specifically means “Ground Transponders Tests/Trials”, but the exact meaning is moot – it is within a meaningful set of codes); what if they tasked ZD576 (being up there already, newly suitably equipped – in fact the only Chinook in NI so equipped – after the recent upgrade to MK2, and after all it was for the benefit of such helicopters doing that leg) to evaluate a PRC-112 set placed at the Mull helipad as a cheap solution for a DME beacon? Would it not have been entirely appropriate to have been squawking 7760 – just to remind ATC if it did an unusual maneuver, like a closer approach than normal for the conditions?
Perhaps that ZD576 was the first to use it goes a long way to explaining the unfamiliarity of the suggested practice to other pilots; no doubt, after the disaster, it would not have been used for a while – and many would not like it to have been made public. ATC Aldergrove could clear this up by stating what squawk code they had been picking up from ZD576 before the crash – and any specific meaning that it had.
<<This could have been the intention of one of the crew, indicating that some form of emergency had occurred.>>
This was suggested the inquiries; two points:
1 I remember reading somewhere on SSR codes that it may not be desirable or prudent to change (or attempt to change) the code in an emergency in certain situations (I’ll leave it to you airmen to look this up yourselves) – I can’t see what would have been the point in the limited time that they would have had and it may have caused his confusion (possibly one of the conditions where it is not recommended to attempt change?);
2 ATC had them for at least part of that leg – what code was ATC detecting prior to the problem (no more generalizations, please)? – oh, and see above!
You wrote:
<<SuperTANS incorporates GPS positioning so why bother with a separate system that, you tell us, gives a range-only readout?>>
SuperTans is a hybrid system that takes input from both GPS and Doppler radar. The Doppler gives speed vectors to the computer for interpolating between GPS point positions and by way of mathematical filters the computer combines the information.
Each component has its own typical errors and, as the combination of the components is mathematically complex, if one component is poor or spurious the computed position can be much worse than could expected from the other component alone.
The Doppler radar requires a decent return from the ground and is notoriously unreliable over water – it was fortuitous that the TANS was accurate at the point of impact. This crew knew of the inaccuracy of the TANS (one of the pilots having warned the rest of the flight shortly before the final one – and the father of one of the pilots commented on an error of more than a mile in a fly pass he witnessed) – they would certainly not have relied on the SuperTans for a close in turn after a sea crossing.
DME, on the other hand, is normally very accurate and reliable – the ground component would have to be intentionally messed with to give a false reading. If you had doubts over another system (as this crew did in regard to GPS on that day) DME is a good reference to compare with – ZD576s TACAN CU was set to pick up the Machrihanish TACAN (which as you know is part DME) for when it came into LOS.
And:
<< Tandemrotor (a Chinook operator) has not heard of the system you describe so it seems unlikely that it's fitted.>>
Fair enough, ZD576 was the first HC2 in NI (and therefore the first to do this crossing with the avionics upgrade). The upgrade to Mk2 makes the HC2 equivalent to the (US) CH47-D which has the SAR equipment to interrogate the PRC-112 portable ground sets. The SAR equipment (NSN 5895-01-494-5228) just plugs into the AN-ARC 164 radio (as fitted to CH-47Ds).
Just for interest, check out the DME knob on a PRC-112 (stands out like a dog’s balls) – you can get a picture from a manufacturers website – makes it very clear what it can be used for and how easily.
Now to address your comments on my posting entitled “THAT TURN”
I understand the setting of an altimeter – I was making an analogy to try to get the idea over (to readers of this thread) of how having an instrument reading can bias one’s visual judgment. I was not suggesting that they were descending at all – just using a vertical judgment analogy with the problem of judging their distance off the mist covered landmass with the possible influence of a distance measuring readout (that may have been incorrect).
<<The altimeter is only as accurate as the Regional Pressure Setting (RPS) that is set on its subscale. The RPS is forecast by the National Met Office (nr London) and is notoriously unreliable. This flight was carried out entirely within the Belfast Altimeter Setting Region and the same RPS is used all over it, even though the actual pressure could vary by several millibars within this area - the altimeter is therefore not to be trusted.>>
As I tried to explain above, the detail of the altimeter is irrelevant, but what you say is of interest – I have learned something. How things have changed from when I was young – I thought the QFE (“atmospheric pressure at aerodrome elevation”) on the ground at the departure airfield was set by zeroing the altimeter (by way of adjusting the pressure setting dial) so giving good accuracy for local flight.
<< The ground is not featureless - it includes one of the best features available, a coastline.>>
Yeh, right – want to check out the picture referred to at the beginning of this posting? They would have been OK once over and parallel to the actual shoreline (the mist forms over the ground as the air rises and so the actual shoreline is clearly visible below). They could have stayed well clear – it was clear at sea – but how well clear? The problem was closing the gap from an obviously safe distance to being safe parallel above the shoreline without slowing down appreciably. As I have tried to describe so often, now, this one turn would have been awkward for anyone to judge in those all too common conditions – spoiling a nice low level flight with an arbitrary, often arguably unnecessary, early, untidy turn if playing it safe.
<<The countdown you have described is not part of Standard Operating Procedures.>>
The book “Chinook” by David McMullen suggests very active involvement in navigation by the non-pilot crew – I just suggested that one of them may have been watching the SAR readout (I don’t know what you call it).
<<IF the portable IFF that you have described exists, the fact that it might not be in the position at which you believe it to be is a very good reason not to trust it in the way that you suggest.>>
Fixed DME ground equipment (often co-located with VOR, especially as a TACAN) can be tampered with very easily to give a false reading (by altering temporarily the fixed delay) – this does not stop its use as such tampering is not generally anticipated; the portable unit could easily be moved, or possibly switched off and another out of position switched on – well, the debate on this thread should tell you that such action would not have been anticipated!
<<I believe that your suggestion can therefore be discounted.>> and it has been for 10 years! I think more strongly than ever that it deserves consideration, though.
Well, where does all this leave us?
At least most of you can now appreciate the local weather conditions.
And the debate on this thread has made it clear to all that the intended flight path was low level with a slight turn up the coast.
Perhaps now you can also comprehend that this HC2 had the capability to interrogate a portable set in DME mode.
I believe that not only were they using a DME beacon but that they were tasked to do so (the squawk code is the vital clue). Whether such a beacon was correct or not, its exclusion from consideration at the inquiries renders the verdicts on the pilots untenable. As this is one way to clear their names, why not make the effort to get the squawk code as received by ATC (or as known to be allocated)?
Look at the picture posted by Tarnished 1st September on Mil Aircrew thread entitled
“Typhoons and Reds” .
Apart from being a great shot, look at the mist on the other side of the water – readers not so familiar with localized coastal mist like on the Mull that day can get an idea of the problem using this picture and a bit of imagination, thus:
imagine the middle bit extending across the whole field of view (put your hands over each side to mask the shoreline);
use some tape to mask the aircraft and that one wave;
imagine the top disappears into the cloud base of the same colour;
then you would have the kind of view that would commonly confront crews approaching from NI on the leg to the Mull lighthouse – see the difference?
Common sense dictates that you would have to stay well clear if relying on visual judgment alone – you wrote:
<<There is nothing awkward about this turn so no special arrangement would be necessary. It is the kind of turn made every day by helicopters (and fixed-wing aircraft) on low-altitude flights. Indeed, this appears to have been a "regularly used leg" (your words) - hardly a likely situation if there was any extra element of risk involved.>>
I believe that it was a regular thing to turn in close as described to me by a witness who had reason to know – and while talking to him near the crash site in identical weather conditions one did just that. I believe that it was risky to have approached closer than, say, the waypoint change in these conditions unless they had something else to go on, never mind aiming to turn right on the coastline.
You wrote:
<<Mode 3/A is the standard ATC mode used by all military and civilian transponders.>>
Yes, I apologize for getting confused with some technical information on a commercial (private) system that does it all – in an HC2 (i.e. MK2 equivalent to CH47-D), a separate interrogator is plugged into the (AN-ARC 164) radio (as is fitted to the MK2 Chinook) – mode 3a is significant here only in that it was the correct mode to squawk a code describing the activity of the aircraft. The (US, don’t know NATO at moment) NSN # of such an interrogator is 5895-01-494-5228.
And:
<< I don't know about the sets fitted to Chinooks, but on some military IFF sets, having the first 2 digits set to 77, irrespective of the settings of the 3rd and 4th digits, identifies to ATC as an emergency squawk.>>
Not so:
There are many international references to squawk codes (including one I have found specific on 7760 being associated with ground transponders) but what the UK military uses would be classified and so I cannot myself absolutely confirm the meaning of 7760 to this flight – it would be nice if someone who could would come forward.
Just to counter your broad dismissal that anything starting 77** means an emergency squawk, I can quickly grab this reference:
<<ICAO CAL Edition 2
Supplement to EUR ANP FASID May 2003
Code 7776 and Code 7777 are reserved for SSR ground transponder
monitoring.>> - please note the first 2 digits are “77”.
Another that suggests that 7760 has an interesting meaning is:
<< RRR 7750-7799 ANDOVER RAF SPECIAL TASKS>>
If Boscombe Down had wanted to evaluate a new NavAid on the Mull and had sent its old workhorse up there, it would have been entirely appropriate for that aircraft to have been squawking 7760 (I think it specifically means “Ground Transponders Tests/Trials”, but the exact meaning is moot – it is within a meaningful set of codes); what if they tasked ZD576 (being up there already, newly suitably equipped – in fact the only Chinook in NI so equipped – after the recent upgrade to MK2, and after all it was for the benefit of such helicopters doing that leg) to evaluate a PRC-112 set placed at the Mull helipad as a cheap solution for a DME beacon? Would it not have been entirely appropriate to have been squawking 7760 – just to remind ATC if it did an unusual maneuver, like a closer approach than normal for the conditions?
Perhaps that ZD576 was the first to use it goes a long way to explaining the unfamiliarity of the suggested practice to other pilots; no doubt, after the disaster, it would not have been used for a while – and many would not like it to have been made public. ATC Aldergrove could clear this up by stating what squawk code they had been picking up from ZD576 before the crash – and any specific meaning that it had.
<<This could have been the intention of one of the crew, indicating that some form of emergency had occurred.>>
This was suggested the inquiries; two points:
1 I remember reading somewhere on SSR codes that it may not be desirable or prudent to change (or attempt to change) the code in an emergency in certain situations (I’ll leave it to you airmen to look this up yourselves) – I can’t see what would have been the point in the limited time that they would have had and it may have caused his confusion (possibly one of the conditions where it is not recommended to attempt change?);
2 ATC had them for at least part of that leg – what code was ATC detecting prior to the problem (no more generalizations, please)? – oh, and see above!
You wrote:
<<SuperTANS incorporates GPS positioning so why bother with a separate system that, you tell us, gives a range-only readout?>>
SuperTans is a hybrid system that takes input from both GPS and Doppler radar. The Doppler gives speed vectors to the computer for interpolating between GPS point positions and by way of mathematical filters the computer combines the information.
Each component has its own typical errors and, as the combination of the components is mathematically complex, if one component is poor or spurious the computed position can be much worse than could expected from the other component alone.
The Doppler radar requires a decent return from the ground and is notoriously unreliable over water – it was fortuitous that the TANS was accurate at the point of impact. This crew knew of the inaccuracy of the TANS (one of the pilots having warned the rest of the flight shortly before the final one – and the father of one of the pilots commented on an error of more than a mile in a fly pass he witnessed) – they would certainly not have relied on the SuperTans for a close in turn after a sea crossing.
DME, on the other hand, is normally very accurate and reliable – the ground component would have to be intentionally messed with to give a false reading. If you had doubts over another system (as this crew did in regard to GPS on that day) DME is a good reference to compare with – ZD576s TACAN CU was set to pick up the Machrihanish TACAN (which as you know is part DME) for when it came into LOS.
And:
<< Tandemrotor (a Chinook operator) has not heard of the system you describe so it seems unlikely that it's fitted.>>
Fair enough, ZD576 was the first HC2 in NI (and therefore the first to do this crossing with the avionics upgrade). The upgrade to Mk2 makes the HC2 equivalent to the (US) CH47-D which has the SAR equipment to interrogate the PRC-112 portable ground sets. The SAR equipment (NSN 5895-01-494-5228) just plugs into the AN-ARC 164 radio (as fitted to CH-47Ds).
Just for interest, check out the DME knob on a PRC-112 (stands out like a dog’s balls) – you can get a picture from a manufacturers website – makes it very clear what it can be used for and how easily.
Now to address your comments on my posting entitled “THAT TURN”
I understand the setting of an altimeter – I was making an analogy to try to get the idea over (to readers of this thread) of how having an instrument reading can bias one’s visual judgment. I was not suggesting that they were descending at all – just using a vertical judgment analogy with the problem of judging their distance off the mist covered landmass with the possible influence of a distance measuring readout (that may have been incorrect).
<<The altimeter is only as accurate as the Regional Pressure Setting (RPS) that is set on its subscale. The RPS is forecast by the National Met Office (nr London) and is notoriously unreliable. This flight was carried out entirely within the Belfast Altimeter Setting Region and the same RPS is used all over it, even though the actual pressure could vary by several millibars within this area - the altimeter is therefore not to be trusted.>>
As I tried to explain above, the detail of the altimeter is irrelevant, but what you say is of interest – I have learned something. How things have changed from when I was young – I thought the QFE (“atmospheric pressure at aerodrome elevation”) on the ground at the departure airfield was set by zeroing the altimeter (by way of adjusting the pressure setting dial) so giving good accuracy for local flight.
<< The ground is not featureless - it includes one of the best features available, a coastline.>>
Yeh, right – want to check out the picture referred to at the beginning of this posting? They would have been OK once over and parallel to the actual shoreline (the mist forms over the ground as the air rises and so the actual shoreline is clearly visible below). They could have stayed well clear – it was clear at sea – but how well clear? The problem was closing the gap from an obviously safe distance to being safe parallel above the shoreline without slowing down appreciably. As I have tried to describe so often, now, this one turn would have been awkward for anyone to judge in those all too common conditions – spoiling a nice low level flight with an arbitrary, often arguably unnecessary, early, untidy turn if playing it safe.
<<The countdown you have described is not part of Standard Operating Procedures.>>
The book “Chinook” by David McMullen suggests very active involvement in navigation by the non-pilot crew – I just suggested that one of them may have been watching the SAR readout (I don’t know what you call it).
<<IF the portable IFF that you have described exists, the fact that it might not be in the position at which you believe it to be is a very good reason not to trust it in the way that you suggest.>>
Fixed DME ground equipment (often co-located with VOR, especially as a TACAN) can be tampered with very easily to give a false reading (by altering temporarily the fixed delay) – this does not stop its use as such tampering is not generally anticipated; the portable unit could easily be moved, or possibly switched off and another out of position switched on – well, the debate on this thread should tell you that such action would not have been anticipated!
<<I believe that your suggestion can therefore be discounted.>> and it has been for 10 years! I think more strongly than ever that it deserves consideration, though.
Well, where does all this leave us?
At least most of you can now appreciate the local weather conditions.
And the debate on this thread has made it clear to all that the intended flight path was low level with a slight turn up the coast.
Perhaps now you can also comprehend that this HC2 had the capability to interrogate a portable set in DME mode.
I believe that not only were they using a DME beacon but that they were tasked to do so (the squawk code is the vital clue). Whether such a beacon was correct or not, its exclusion from consideration at the inquiries renders the verdicts on the pilots untenable. As this is one way to clear their names, why not make the effort to get the squawk code as received by ATC (or as known to be allocated)?