Chinook - Still Hitting Back 3 (Merged)
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Yet the crew (apparently), switched of a fully functioning TANS while approaching a cloud covered headland at high speed.
Does anyone on my planet think that is a logical explanation of events?
Does anyone on my planet think that is a logical explanation of events?
They also apparently switched from waypoint A to waypoint B just before switching off the system.
My personal experience, as a grunt, of ops in NI just prior to this period is that crews navigated 'eyes out' with the systems as a check.
In particular I remember a 1989 flight in a gazelle where the pilot set the nav system, which I presume was some relation of TANS, prior to takeoff. We then flew BBK, NTH, XMG, FKH and back to BBK landing at precisely the same spot, after about 20/30 minutes, and the nav system was 200m out.
EG
If the crew were having problems with the TANS, the first port of call would be SELECT DOPPLER
Perhaps their thought process was complicated by "So that's why it isn't cleared for use". Followed by "Is the Doppler cleared?". (No). "Is the GPS cleared"? (No). Easier just to list the avionics that were cleared for use. (None).
We just don't know, but that uncertainty is exactly what makes the verdict unsustainable. The fact that the clearance/release regulations were simply not implemented at that time compound the injustice.
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Good Day.
I wonder if I could pose question here, without wishing to enter the discussion on the main purpose of this thread (I have no useful input).
I have often wondered why all these security chaps were on this chopper. I recently discussed this issue with a retired CID officer over a bevy on holiday...and he was of the opinion that it had never been fully explained. I believe I've heard they were on their way to a conference at Fort George near Inverness, but if that is true surely it begs a number of questions...
Why go to this out of way place for a conference, thus creating the need for an unusual transport solution?
Why not take the ferry and have the conference on the West Coast of Scotland or fly to London and have the conference there?
I'm not seeking to unearth a conspiracy, just an inquisitive desire to answer one of the aspects of this tragedy that has always puzzled me.
Apologies if the intrusion is unwelcome.
I wonder if I could pose question here, without wishing to enter the discussion on the main purpose of this thread (I have no useful input).
I have often wondered why all these security chaps were on this chopper. I recently discussed this issue with a retired CID officer over a bevy on holiday...and he was of the opinion that it had never been fully explained. I believe I've heard they were on their way to a conference at Fort George near Inverness, but if that is true surely it begs a number of questions...
Why go to this out of way place for a conference, thus creating the need for an unusual transport solution?
Why not take the ferry and have the conference on the West Coast of Scotland or fly to London and have the conference there?
I'm not seeking to unearth a conspiracy, just an inquisitive desire to answer one of the aspects of this tragedy that has always puzzled me.
Apologies if the intrusion is unwelcome.
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My final TANS entry (for now anyway)
After PM's to a couple of other contributors, I am more than ever convinced that none of us fully understands the implications of the final entries into the TANS followed by the (apparent), deliberate switch off by the crew. Further research by a real expert is needed.
A couple of items are worth highlighting before I withdraw from this subject.
1. Read again para 1.1.5 from The RACAL report in Brian's last entry. RACAL concede that no reconstruction based on the TANS can be considered anywhere near factual.
2. If the TANS were operating to anywhere near the accuracies of the report the crew would never deliberately switch it off. It would be too useful in primary and secondary modes.
Can I offer any explanations?
1. Read the many excellent entries by Tucumseh. Is it possible that EMC problems made the TANS more of a problem than a solution?
2. Was the RACAL report so flawed that it had no validity at all?
I Know of at least six incidents on the C130 HINS Navigation computer where the equipment was in error by up to 60nms without displaying error codes. The groundcrew could not replicate the fault on the ground. All these six computers were undamaged.
3. The TANS was spot on but the crew, for whatever reason, chose not to accept the information. Spatial Disorientation? It has happened.
All theories based on past experience. But still only theories.
A couple of items are worth highlighting before I withdraw from this subject.
1. Read again para 1.1.5 from The RACAL report in Brian's last entry. RACAL concede that no reconstruction based on the TANS can be considered anywhere near factual.
2. If the TANS were operating to anywhere near the accuracies of the report the crew would never deliberately switch it off. It would be too useful in primary and secondary modes.
Can I offer any explanations?
1. Read the many excellent entries by Tucumseh. Is it possible that EMC problems made the TANS more of a problem than a solution?
2. Was the RACAL report so flawed that it had no validity at all?
I Know of at least six incidents on the C130 HINS Navigation computer where the equipment was in error by up to 60nms without displaying error codes. The groundcrew could not replicate the fault on the ground. All these six computers were undamaged.
3. The TANS was spot on but the crew, for whatever reason, chose not to accept the information. Spatial Disorientation? It has happened.
All theories based on past experience. But still only theories.
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I know the power switch on the RNS252 Supertans was discovered in the off position amongst the wreckage, but if anyone can point me to a SOURCE document suggesting this selection is likely to have occurred prior to the sequence of multiple impacts, I would be most grateful?
I may very well be wrong, but I don't recall crew selection being the conclusion of the AAIB??
I may very well be wrong, but I don't recall crew selection being the conclusion of the AAIB??
The AAIB report states (para 7.2.16);
That is as near a "source" document as you will find; it is certainly authoritative in the sense the AAIB had vast experience of determining switch positions from sooting patterns.
The AAIB report covers this crucial device in a single paragraph, their only statement being about the switch. They simply point the reader to the Racal report which the AAIB have obviously been told is authoritative. But, clearly, the author felt the need to make the point that there was an unexplained conflict - he simply stated a fact and if someone else implied otherwise it was up to the BoI to de-conflict.
Nowhere in any of the papers I've seen is there an attempt to ask what the effect of switching OFF is - i.e. the question of whether the device continues to process in the background, but not display.
Yet, Trimble 8000 GPS is covered by a detailed and independent AAIB report.
MoD's case (waypoint change, timings etc) relies entirely on Racal's interpretation of their own device - a device which was not cleared for use and which the pilots were deeply suspicious of. So, MoD didn't have sufficient confidence to clear it, but after the event regarded it as infallible. And all the above was considered in isolation, lacking a systems overview.
"The ON/OFF switch was found at OFF, and an absence of substantial damage to the lift-toggle type switch, including the ramp mechanism, together with ground fire sooting patterns suggested this had been the setting at impact".
That is as near a "source" document as you will find; it is certainly authoritative in the sense the AAIB had vast experience of determining switch positions from sooting patterns.
The AAIB report covers this crucial device in a single paragraph, their only statement being about the switch. They simply point the reader to the Racal report which the AAIB have obviously been told is authoritative. But, clearly, the author felt the need to make the point that there was an unexplained conflict - he simply stated a fact and if someone else implied otherwise it was up to the BoI to de-conflict.
Nowhere in any of the papers I've seen is there an attempt to ask what the effect of switching OFF is - i.e. the question of whether the device continues to process in the background, but not display.
Yet, Trimble 8000 GPS is covered by a detailed and independent AAIB report.
MoD's case (waypoint change, timings etc) relies entirely on Racal's interpretation of their own device - a device which was not cleared for use and which the pilots were deeply suspicious of. So, MoD didn't have sufficient confidence to clear it, but after the event regarded it as infallible. And all the above was considered in isolation, lacking a systems overview.
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As you probably know, I was a technical advisor to one of the legal teams at the FAI. As such I framed questions, and instigated supplementary inquiries to various agencies, including the AAIB, in preparation for the (then) upcoming FAI. A very lonely time I might add!!
I had further correspondence with the AAIB, asking supplementary questions requiring further wreckage examination. For example I requested further analysis to determine whether the forward cabin upper door was open or closed at impact. This could have been significant, but had been overlooked initially.
My memory may well be inaccurate, however I recollect having a discussion with the Senior Investigator of Air Accidents, the very impressive Mr Tony Cable whilst standing in a very depressing hangar at Farnboro. I thought he said the position of the switch was not necessarily reliable as the sequence of severe multiple impacts may have affected it.
I am away from my documents for a little while, but there is a section in the AAIB report which allocates a confidence level to all cockpit indications recovered from ZD576. Isn't this switch included in that list??
I had further correspondence with the AAIB, asking supplementary questions requiring further wreckage examination. For example I requested further analysis to determine whether the forward cabin upper door was open or closed at impact. This could have been significant, but had been overlooked initially.
My memory may well be inaccurate, however I recollect having a discussion with the Senior Investigator of Air Accidents, the very impressive Mr Tony Cable whilst standing in a very depressing hangar at Farnboro. I thought he said the position of the switch was not necessarily reliable as the sequence of severe multiple impacts may have affected it.
I am away from my documents for a little while, but there is a section in the AAIB report which allocates a confidence level to all cockpit indications recovered from ZD576. Isn't this switch included in that list??
Tandemrotor
The list you speak of is comprehensive, but under RNS252 it simply says "See Racal report". As I said, AAIB were obviously told that was the authoritative (and clearly fully independent
) source document. You mention Mr Cable, but he was not the AAIB investigator for this aspect. As such, I think it significant that he made a point of highlighting this unexplained conflict. He is indeed truly impressive and I hope Lord Philip asks him his professional opinion on the many aspects ignored by the BoI and MoD.
Regarding the RNS252 report, do people not find it odd that Racal were permitted to decide what functions, data, switch positions etc were "considered relevant to the investigation" (their words) and determined the content of the report. So, for example, they did not mention the on/off switch when one would expect them to explain given the fact that it was found OFF. I'm afraid if I were on the BoI I'd jump and demand full evidence and explanations.
The report, rightly, studiously avoids claiming the unit was powered until impact, merely using the term "power down". It does not, to my mind, satisfactorily explain the statement that RNS252 "powered down" 26 seconds before GPS (or 34.2 seconds, depending on which part of the report you read, but who am I to argue with 8.2 seconds). A period of time some may think very close to the time taken to get from Waypoint acceptance to point of impact. That alone warrants a proper explanation, not mere speculation.
The list you speak of is comprehensive, but under RNS252 it simply says "See Racal report". As I said, AAIB were obviously told that was the authoritative (and clearly fully independent
) source document. You mention Mr Cable, but he was not the AAIB investigator for this aspect. As such, I think it significant that he made a point of highlighting this unexplained conflict. He is indeed truly impressive and I hope Lord Philip asks him his professional opinion on the many aspects ignored by the BoI and MoD. Regarding the RNS252 report, do people not find it odd that Racal were permitted to decide what functions, data, switch positions etc were "considered relevant to the investigation" (their words) and determined the content of the report. So, for example, they did not mention the on/off switch when one would expect them to explain given the fact that it was found OFF. I'm afraid if I were on the BoI I'd jump and demand full evidence and explanations.
The report, rightly, studiously avoids claiming the unit was powered until impact, merely using the term "power down". It does not, to my mind, satisfactorily explain the statement that RNS252 "powered down" 26 seconds before GPS (or 34.2 seconds, depending on which part of the report you read, but who am I to argue with 8.2 seconds). A period of time some may think very close to the time taken to get from Waypoint acceptance to point of impact. That alone warrants a proper explanation, not mere speculation.
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REFRESHER
The weather conditions of the day were typical and would not have hidden the presence of the landmass but would have obscured/blurred detail (what little there is there) and made visual judgement of range to it very difficult.
The STANS had been in GPS mode such that the CDU would have been displaying data for just that system.
If one uses for analysis just GPS data for the flight from Aldergrove to the position of waypoint change, you get a straight track sticking right on 027 mag (at the time) – with no other nav aids available at their altitude and a 20 mile sea crossing with a landmass ahead bereft of identifiable aiming points and with a cross wind component they simply had to have been using STANS to have kept so closely on track.
So the switch position being found “off” does not mean that it was off during the flight because it obviously was on.
The selection of waypoint B should be considered along with Flt Lt Tapper's course selector (on his Horizontal Situation Indicator) being on 028 – this surely showed intent to continue the flight (after the business at the Mull) by heading out to sea and joining the 028-B track along the shores Islay/Jura (an obvious straight safe run) – and therefore there was no intention to switch off the TANS (by the crew at least).
But those of you familiar with the kit would probably think it unlikely in the extreme that such a toggle switch could have been bounced “off” - especially when the nature of the impact saved so much of the instrumentation. But it was off before smoke had time to deposit the soot (that had AAIB deducing it to have been off at impact) – but the ground fire did not engulf the cockpit area – and so there was an opportunity for some kind hearted soul with a little knowledge to turn off the nav computer perhaps hoping to save us the agony of analysis – pity about the back-up battery, eh?.
Up until the position of waypoint change, use of GPS for area nav would not have broken any rules as they would have been flying eyes out for safety – just using GPS as a guide.
However, Flt Lt Tapper in particular would not have relied upon it to any degree of accuracy and would not have been expected to have relied upon it for giving range off the Mull shoreline as close in as waypoint change with those conditions ahead without some other reference and he would probably not have been alarmed at a significant discrepancy between TANS and some other local reference that may have been available.
I suggest that he had some other local reference that he trusted more than TANS to have changed the waypoint at that time – effectively discarding TANS for position relative to the nearby landmass – they were already too close in for safety to have been just turning nearby – they must have had an intention to approach a specific point (I have presented the argument for this in detail in past posts).
I believe that they were intending to swing around the light house at speed, the line up being facilitated by someone with a PRC112 at the HLS at waypoint A – this diagram may help:
I believe that the person with the PRC112 was wilfully out of position, that this crash was contrived. The security personnel on board were perceived as an obstacle to the peace process and so these good people were bundled onto one aircraft – against all common sense and with two Sea Kings already available for the task – which just happened to crash into an isolated low hill. The official story has been rubbish (remember the “inappropriate rate of climb” nonsense?) - pilot error beyond any doubt whatsoever! – and you lot have let them get away with it for 16 years.
The weather conditions of the day were typical and would not have hidden the presence of the landmass but would have obscured/blurred detail (what little there is there) and made visual judgement of range to it very difficult.
The STANS had been in GPS mode such that the CDU would have been displaying data for just that system.
If one uses for analysis just GPS data for the flight from Aldergrove to the position of waypoint change, you get a straight track sticking right on 027 mag (at the time) – with no other nav aids available at their altitude and a 20 mile sea crossing with a landmass ahead bereft of identifiable aiming points and with a cross wind component they simply had to have been using STANS to have kept so closely on track.
So the switch position being found “off” does not mean that it was off during the flight because it obviously was on.
The selection of waypoint B should be considered along with Flt Lt Tapper's course selector (on his Horizontal Situation Indicator) being on 028 – this surely showed intent to continue the flight (after the business at the Mull) by heading out to sea and joining the 028-B track along the shores Islay/Jura (an obvious straight safe run) – and therefore there was no intention to switch off the TANS (by the crew at least).
But those of you familiar with the kit would probably think it unlikely in the extreme that such a toggle switch could have been bounced “off” - especially when the nature of the impact saved so much of the instrumentation. But it was off before smoke had time to deposit the soot (that had AAIB deducing it to have been off at impact) – but the ground fire did not engulf the cockpit area – and so there was an opportunity for some kind hearted soul with a little knowledge to turn off the nav computer perhaps hoping to save us the agony of analysis – pity about the back-up battery, eh?.
Up until the position of waypoint change, use of GPS for area nav would not have broken any rules as they would have been flying eyes out for safety – just using GPS as a guide.
However, Flt Lt Tapper in particular would not have relied upon it to any degree of accuracy and would not have been expected to have relied upon it for giving range off the Mull shoreline as close in as waypoint change with those conditions ahead without some other reference and he would probably not have been alarmed at a significant discrepancy between TANS and some other local reference that may have been available.
I suggest that he had some other local reference that he trusted more than TANS to have changed the waypoint at that time – effectively discarding TANS for position relative to the nearby landmass – they were already too close in for safety to have been just turning nearby – they must have had an intention to approach a specific point (I have presented the argument for this in detail in past posts).
I believe that they were intending to swing around the light house at speed, the line up being facilitated by someone with a PRC112 at the HLS at waypoint A – this diagram may help:
I believe that the person with the PRC112 was wilfully out of position, that this crash was contrived. The security personnel on board were perceived as an obstacle to the peace process and so these good people were bundled onto one aircraft – against all common sense and with two Sea Kings already available for the task – which just happened to crash into an isolated low hill. The official story has been rubbish (remember the “inappropriate rate of climb” nonsense?) - pilot error beyond any doubt whatsoever! – and you lot have let them get away with it for 16 years.
I believe that the person with the PRC112 was wilfully out of position, that this crash was contrived.
Walt, this theory of yours has been debunked many times. It really is time you dropped it.
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A fit man could walk back to Macrihanish, where candidates for helping with said kit were based - but they did disappear a few weeks later, didn't they? - back over the pond, wasn't it?
In 1996, I spoke to a landlady in Campbeltown who had had a young American SEAL staying there - for a few nights after the crash, the poor lad had apparently had terrible nightmares, waking the whole guesthouse with his screams, and his mattress was so soaked in sweat that she had to throw it out.
Just circumstantial but a lot more likely person of interest than a green man with a flying saucer.
On what grounds has the theory of a controlled approach to a known HLS marked with a PRC112 been debunked? Please point it out and save me wasting my time.
In 1996, I spoke to a landlady in Campbeltown who had had a young American SEAL staying there - for a few nights after the crash, the poor lad had apparently had terrible nightmares, waking the whole guesthouse with his screams, and his mattress was so soaked in sweat that she had to throw it out.
Just circumstantial but a lot more likely person of interest than a green man with a flying saucer.
On what grounds has the theory of a controlled approach to a known HLS marked with a PRC112 been debunked? Please point it out and save me wasting my time.
Walter:
Well you know that Walter, as did Wratten & Day, and so do I now that you tell me it was so, but just as a matter of interest, how do you know? Is it because it fits your version of events that the "playback" of its parameters constituted such a major part of the MOD's "old evidence" on which their disreputable stance is based?
In contrast a respected and professional AAIB Inspector is on record as saying that he believed the switch to have been "Off" at impact. So we are faced with believing you and Senior RAF Air Officers, or believing a professional Air Accident Inspector. If by any chance he is right it not only calls your murder allegations into question, but the whole basis of the RAF's Gross Negligence "Finding". Never did so much hang on the position of one little switch, I suspect.
So the switch position being found “off” does not mean that it was off during the flight because it obviously was on.
In contrast a respected and professional AAIB Inspector is on record as saying that he believed the switch to have been "Off" at impact. So we are faced with believing you and Senior RAF Air Officers, or believing a professional Air Accident Inspector. If by any chance he is right it not only calls your murder allegations into question, but the whole basis of the RAF's Gross Negligence "Finding". Never did so much hang on the position of one little switch, I suspect.
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I believe that I gave the reasoning for it having been on in the critical phase - work through it again and it should be logical to you. Whether it was switched off after impact or somehow got like that due to impact or for whatever reason, it had been functioning and, as I have argued, had to have been used at least up to the position of waypoint change and the stored GPS data thereafter was consistent with the system continuing normal processing - as Tuc asks, it would be interesting to know if switching off just cuts off the CDU or stops all processing - but it does not matter.
If you did your own detailed chartwork using just GPS data from the nav data (as opposed to getting mixed up with the Doppler) I think you would see that it all fits.
Pulse
I thought that myself at the time and asked her - she said that it was not uncommon for some of them to have digs off the station - no matter, it was just what I was told by the landlady of one of the bigger B&B establishments - I was staying there and it just came up in conversation about the crash.
The bottom line is that detailed analysis of all the known data so strongly suggested a controlled approach to a known HLS that I predicted, with the difficulties that the weather gave for identifying a particular point on the land and judging closing range to it, that such a crew would only have closed in confidently with a PRC112 marking the spot - the fit was only confirmed subsequent to the analysis and so this is a classic case of QED - good proof.
At the very least, a scenario worth investigating fully - however uncomfortable to confront.
I believe that I gave the reasoning for it having been on in the critical phase - work through it again and it should be logical to you. Whether it was switched off after impact or somehow got like that due to impact or for whatever reason, it had been functioning and, as I have argued, had to have been used at least up to the position of waypoint change and the stored GPS data thereafter was consistent with the system continuing normal processing - as Tuc asks, it would be interesting to know if switching off just cuts off the CDU or stops all processing - but it does not matter.
If you did your own detailed chartwork using just GPS data from the nav data (as opposed to getting mixed up with the Doppler) I think you would see that it all fits.
Pulse
I thought that myself at the time and asked her - she said that it was not uncommon for some of them to have digs off the station - no matter, it was just what I was told by the landlady of one of the bigger B&B establishments - I was staying there and it just came up in conversation about the crash.
The bottom line is that detailed analysis of all the known data so strongly suggested a controlled approach to a known HLS that I predicted, with the difficulties that the weather gave for identifying a particular point on the land and judging closing range to it, that such a crew would only have closed in confidently with a PRC112 marking the spot - the fit was only confirmed subsequent to the analysis and so this is a classic case of QED - good proof.
At the very least, a scenario worth investigating fully - however uncomfortable to confront.
Walter:-
I am fairly certain that the last 5 words in your quote are yours and not tuc's, because it does matter, very much. I don't query that superTANS was on and in use during the flight, quite possibly right up until WP change. What I do doubt is that it was selected ON at impact, because Mr Cable believes that it wasn't and I believe him.
So the question is why did the crew select it OFF, so soon before crashing? It seems to me highly probable that action was a desperate attempt to resolve a serious malfunction that they suspected, rightly or wrongly, was caused by EMI. They didn't know as much as we do now about the Gross Negligence that had forced this grossly unairworthy aircraft into Squadron Service, but they knew enough to distrust it completely. That switch position was their verdict on the airworthiness of ZD576 and their message to fellow aviators. Typically it was ignored by the BoI, the AOC, the AOC-in-C, and the MOD, but was picked up by the AAIB. If there was ever proof that the RAF is not to be trusted to conduct Military Air Accident Investigations, it is in the position of that little switch in the crash debris.
as Tuc asks, it would be interesting to know if switching off just cuts off the CDU or stops all processing - but it does not matter.
So the question is why did the crew select it OFF, so soon before crashing? It seems to me highly probable that action was a desperate attempt to resolve a serious malfunction that they suspected, rightly or wrongly, was caused by EMI. They didn't know as much as we do now about the Gross Negligence that had forced this grossly unairworthy aircraft into Squadron Service, but they knew enough to distrust it completely. That switch position was their verdict on the airworthiness of ZD576 and their message to fellow aviators. Typically it was ignored by the BoI, the AOC, the AOC-in-C, and the MOD, but was picked up by the AAIB. If there was ever proof that the RAF is not to be trusted to conduct Military Air Accident Investigations, it is in the position of that little switch in the crash debris.
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So the question is why did the crew select it OFF, so soon before crashing? It seems to me highly probable that action was a desperate attempt to resolve a serious malfunction that they suspected, rightly or wrongly, was caused by EMI.
1. ZD576 approaches waypoint A.
2. Crew select waypoint B.
3. At that moment or very shortly there after some sort of spurious caption/engine run up/UCFM occurs.
4. Crew link 2 to 3 and switch off TANS in attempt to clear 3.
If so seems possible to me.
EG
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Time and motion
Tuc.
I thought that the time difference between the Trimble and Supertans was understood and thought to be insignificant........??????.......
..the gps unit has its own time clock , fed from the satellites and always set to UTC.( GMT/Z...).........whereas the RNS252 has a local clock which can be set manually by the crew to any time of choice . There is no provision to syncronize the two....If they chose not to fly a sortie on Zulu but use the local time, this difference could be plus or minus up to 12 hours in theory..............depending apon which theatre/part of the world they are operating in .........
..with regard to the on/off switch............similar locking toggle switches marketed today by Honywell or Eaton require that the toggle be pulled a mere 2.3 mm outwards ( about 3/32 inch ).... against a spring , in order to allow movement........not a great distance when there are significant G forces involved in decelerating from flying speed to zero in a short time...............if the unit stopped in about 8 feet for instance it is subjected to 100G , so if the toggle arm weighed 5grams normally it would behave as if it were weighing 1/2 kilo briefly......and if it were pointing in the direction of travel I think that would be enough to unlock the toggle...
rgds Robin.....
I thought that the time difference between the Trimble and Supertans was understood and thought to be insignificant........??????.......
..the gps unit has its own time clock , fed from the satellites and always set to UTC.( GMT/Z...).........whereas the RNS252 has a local clock which can be set manually by the crew to any time of choice . There is no provision to syncronize the two....If they chose not to fly a sortie on Zulu but use the local time, this difference could be plus or minus up to 12 hours in theory..............depending apon which theatre/part of the world they are operating in .........
..with regard to the on/off switch............similar locking toggle switches marketed today by Honywell or Eaton require that the toggle be pulled a mere 2.3 mm outwards ( about 3/32 inch ).... against a spring , in order to allow movement........not a great distance when there are significant G forces involved in decelerating from flying speed to zero in a short time...............if the unit stopped in about 8 feet for instance it is subjected to 100G , so if the toggle arm weighed 5grams normally it would behave as if it were weighing 1/2 kilo briefly......and if it were pointing in the direction of travel I think that would be enough to unlock the toggle...
rgds Robin.....
RC
Points taken, but the way I read the two reports the respective system runtimes differ by 34.2s (+/- 0.05) using the same source (GPS), with TANS having the shorter runtime.
I readily conceded the two reports jump between different terminologies at will and sometimes use the term “fix” to describe Lat/Long/Time when they possibly only mean Lat/Long.
These may be explainable but my point is they are not explained or reconciled independently. Racal were allowed to determine what data was “relevant” and, because it seemingly suited the desired outcome, no further investigation was conducted. We now have the complete Racal SuperTANS report, but most of it was heavily redacted at the time, omitting the data that would facilitate such analysis. And, as I said, Racal wrote the report on their own system, but the AAIB wrote the Trimble GPS report.
I make the same point on the toggle switch. The AAIB (who I assume everyone here readily admits are world-renowned experts) stated the switch was off at impact. Racal didn’t say it was on, they just didn’t mention it at all (again, because they were allowed to determined what was and was not in their report). While we both concede it is possible the impact forces moved the switch, yet again the BoI did not seek to resolve the conflict (if, indeed, it was a conflict; something they were also obliged to determine).
The AAIB investigator who stated it was off (Mr Cable) was not the investigator who wrote the Trimble GPS report or oversaw Racal’s work. That being so, one can read between the lines and ask why Mr Cable made a point of stating the switch was off in his single paragraph “SuperTANS” section, which merely mentioned this fact and then referred the reader to the Racal report. It was obviously the only means open to him to voice this concern; or perhaps his words were “sanitised” as the report worked its way through the system to the BoI. It is well known MoD withheld vital and relevant information from the AAIB and I strongly suspect Mr Cable would say much more now that the facts have slowly emerged.
And just to reiterate a final point. MoD and Racal stated the entire Nav system was both serviceable and accurate. (Yet I'd invite anyone to show me were it says it was cleared for use). The AAIB, in their Trimble GPS report, listed faults such as no Time of Day output and a blown FET in the power supply. I’m a mere greenie, but if I found no ToD o/p and a blown FET, there is no way I’d sign a MF731 to say it was serviceable. And the MoD investigation allowed this to slide? Indicative of a Mickey Mouse investigation into a pre-determined cause.
Points taken, but the way I read the two reports the respective system runtimes differ by 34.2s (+/- 0.05) using the same source (GPS), with TANS having the shorter runtime.
I readily conceded the two reports jump between different terminologies at will and sometimes use the term “fix” to describe Lat/Long/Time when they possibly only mean Lat/Long.
These may be explainable but my point is they are not explained or reconciled independently. Racal were allowed to determine what data was “relevant” and, because it seemingly suited the desired outcome, no further investigation was conducted. We now have the complete Racal SuperTANS report, but most of it was heavily redacted at the time, omitting the data that would facilitate such analysis. And, as I said, Racal wrote the report on their own system, but the AAIB wrote the Trimble GPS report.
I make the same point on the toggle switch. The AAIB (who I assume everyone here readily admits are world-renowned experts) stated the switch was off at impact. Racal didn’t say it was on, they just didn’t mention it at all (again, because they were allowed to determined what was and was not in their report). While we both concede it is possible the impact forces moved the switch, yet again the BoI did not seek to resolve the conflict (if, indeed, it was a conflict; something they were also obliged to determine).
The AAIB investigator who stated it was off (Mr Cable) was not the investigator who wrote the Trimble GPS report or oversaw Racal’s work. That being so, one can read between the lines and ask why Mr Cable made a point of stating the switch was off in his single paragraph “SuperTANS” section, which merely mentioned this fact and then referred the reader to the Racal report. It was obviously the only means open to him to voice this concern; or perhaps his words were “sanitised” as the report worked its way through the system to the BoI. It is well known MoD withheld vital and relevant information from the AAIB and I strongly suspect Mr Cable would say much more now that the facts have slowly emerged.
And just to reiterate a final point. MoD and Racal stated the entire Nav system was both serviceable and accurate. (Yet I'd invite anyone to show me were it says it was cleared for use). The AAIB, in their Trimble GPS report, listed faults such as no Time of Day output and a blown FET in the power supply. I’m a mere greenie, but if I found no ToD o/p and a blown FET, there is no way I’d sign a MF731 to say it was serviceable. And the MoD investigation allowed this to slide? Indicative of a Mickey Mouse investigation into a pre-determined cause.
RC:-
Well maybe, but that wasn't Mr Cable's view, nor was it that a highly strung Seal could have leaped into the wreckage moments after the crash (which he had engineered of course) found the switch and turned it OFF, before fire engulfed it and sooted it as OFF thus confusing the issue. I do not think Mr Cable was confused. When he says the switch was OFF on impact what he meant was that, based on years of looking at holes in the ground full of twisted metal, the switch was OFF at impact!
Mind you, Walter is right to suspect a conspiracy here. There was one, and it was to divert attention from the Gross Unairworthiness of ZD576 and put it instead elsewhere, ie on the deceased pilots. That conspiracy still continues to the shame of the Royal Air Force as well as the MOD, which of course has no shame. Tuc sums it up succinctly and correctly as ever when he says of this sham of an Air Accident Inquiry:-
and if it were pointing in the direction of travel I think that would be enough to unlock the toggle...
Mind you, Walter is right to suspect a conspiracy here. There was one, and it was to divert attention from the Gross Unairworthiness of ZD576 and put it instead elsewhere, ie on the deceased pilots. That conspiracy still continues to the shame of the Royal Air Force as well as the MOD, which of course has no shame. Tuc sums it up succinctly and correctly as ever when he says of this sham of an Air Accident Inquiry:-
a Mickey Mouse investigation into a pre-determined cause.