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Chinook - Still Hitting Back 3 (Merged)

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Chinook - Still Hitting Back 3 (Merged)

Old 29th May 2010, 22:34
  #6421 (permalink)  
 
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Boslandew

Were I to suggest to you, that none of the 'weather witnesses' were below the height of the lighthouse (approx 300' asl) and the cyclists Bracher and Ellacott were close to, if not above the accident elevation (810' asl) would you be able to quote evidence to contradict me?
2 It is of course possible (that there were clear conditions below) but there is little to suggest that it was.
But of course there was one witness to give a unique view of the weather at low level; that of the yachtsman Holbrook! He sees the aircraft clearly.

Ergo, isn't it not only possible, but likely, that weather conditions were indeed clear enough for VFR only a very short distance from our land locked observers! Anything else is little more than speculation.

As for cazatou's (K52) earlier suggestion of a 'radar fix', this is of course a complete invention, or simply 'slap dash' research. There was of course no such thing!

Please let's stick to the FACTS chaps, otherwise I will just have to keep coming along to correct you!
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Old 29th May 2010, 22:46
  #6422 (permalink)  
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"then there is no absolute proof that the aircraft was IMC and the case falls." I cannot speak for Brian and the rest, but I would be very surprised if they are hanging their hats on that. The primary objections surely are that the RAF's own recommendations preclude apportioning Gross Negligence to dead crews (and as far as I know that had not happened before or after, which is interesting) and the fact that there remains no proof of the same. If indeed the fog horn was not operating that would support the belief that at sea level the conditions were not a problem.
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Old 29th May 2010, 23:58
  #6423 (permalink)  
 
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Amazingly we seem to be going round the bouys again, hopefully for the very last time. May I remind everyone that Wratten's view, consistantly supported on this thread by John Purdey, was that gross negligence occurred at waypoint change. The only certain thing you can say from the witness evidence is that the crew would never have seen the ground where the land based witnesses were actually standing. The yachtsman's evidence suggests that they were probably in VMC when the Chinook passed him.

Anything else is pure speculation. No-one, including JP, has ever been able to say what the crew could or could not see from the cockpit at waypoint change. Neither can anyone say with any degree of certainty that they were going too fast at that time. These are the two pillars of Wratten's judgement - they were too fast under the conditions at waypoint change. Yet, in the nine years this thread and its predecessor have been running, no-one can say how fast or what the conditions were as seen from that point.
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Old 30th May 2010, 11:11
  #6424 (permalink)  
 
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pulse,

You put into words my thoughts exactly.

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Old 30th May 2010, 11:46
  #6425 (permalink)  
 
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May I remind everyone that Wratten's view, consistantly supported on this thread by John Purdey, was that gross negligence occurred at waypoint change.
Yes, it has been noticed that John Purdey closely supports "Wratten's view". One wonders whether they are joined at the hip.
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Old 30th May 2010, 14:47
  #6426 (permalink)  
 
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Weather on Mull

Tandemrotor

Im sorry but I dont understand your reasoning. I may have missed something, a far from rare occurrence these days.

The yachtsman said that the weather over the sea was clear and that the base of the Mull was visible up to about the level of the lighthouse. It is worth mentioning that the yachtsman did not know until later that the aircraft had crashed and his recollections of the weather are possibly less accurate than those who heard the crash.

However, the aircraft did not crash at sea or at the base of the Mull. It crashed at or close to a point that more than one observer said was in fog, five hundred feet above a point that four witnesses said was in fog and on a hill feature which all witnesses on that feature said was in fog.

Now it is not impossible that somewhere above the light house there was an area of VMC, 1000 metres in all directions and 250ft cloudbase. However, all the available evidence from those actually on the Mull is to the contrary. It seems to me to be a reasonable assumption that there is a high degree of probability that the crash site was in IMC.
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Old 30th May 2010, 22:37
  #6427 (permalink)  
 
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Originally Posted by Boslandew View Post
Tandemrotor

Im sorry but I dont understand your reasoning. I may have missed something, a far from rare occurrence these days.

The yachtsman said that the weather over the sea was clear and that the base of the Mull was visible up to about the level of the lighthouse. It is worth mentioning that the yachtsman did not know until later that the aircraft had crashed and his recollections of the weather are possibly less accurate than those who heard the crash.

However, the aircraft did not crash at sea or at the base of the Mull. It crashed at or close to a point that more than one observer said was in fog, five hundred feet above a point that four witnesses said was in fog and on a hill feature which all witnesses on that feature said was in fog.

Now it is not impossible that somewhere above the light house there was an area of VMC, 1000 metres in all directions and 250ft cloudbase. However, all the available evidence from those actually on the Mull is to the contrary. It seems to me to be a reasonable assumption that there is a high degree of probability that the crash site was in IMC.
Bos,

All the clues are there
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Old 31st May 2010, 12:52
  #6428 (permalink)  
 
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I don't believe that ANY of the campaigners have any doubt (whatsoever!) that the hillside where the aircraft impacted was in IMC at the time of impact, nor that the lighthouse keeper was also standing in IMC, but the fact that the aircraft crashed whilst IMC does not mean that it had been deliberatley flown there.

It is very likely that the aircraft was under control when the Supertans waypoint was changed to a point further up the coast and very likely that this selection indicates that the crew had visual contact with the coastline at the time. What we don't know is why the aircraft did not subsequently turn the necessary few degrees to the left. A number of hypotheses have been put forward in an effort to explain what may have happened but, in the absence of ADR/CVR, we shall never know what DID happen. But we do not know, even 'beyond reasonable doubt' that the reason was the negligence of the crew.

The aircraft's supposed (high) groundspeed is used by Day/Wratten (+ JP et al) as evidence that the crew was already negligent by the time of the waypoint change, in that they were flying too fast for the conditions, but this logic is flawed. An alternative explanation is that, notwithstanding the fog at the crash site, conditions were so good that a high-speed cruise was considered by this highly-experienced crew to be entirely appropriate. Weight is lent to this possibilty (probability?) by Holbrook's evidence and by anecdotal evidence by many on this thread regarding typical orographic conditions (ie often clear conditions in close proximity to the hill fog) in the area.

The MoD could have heeded the findings of the various inquiries already held and reversed this extremely unfair finding of Gross Negligence against Tapper and Cook; this would have left everyone happy, as even Day/Wratten could have conceded that new arguments had come to light and that they had acted in good faith. Now, however, the whole ugly truth about lack of airworthiness has come out and others have been placed in the firing line - those who, in the face of the experts' advice, pushed the HC Mk2 into service in a pretty shameful state.

I agree that the names of the pilots can be cleared pretty quickly, but the new Government should not shrink from a thorough and independent inquiry into the circumstances surrounding the entry into Service of this immature aircraft and why, despite no actual evidence, messrs Wratten/Day came to their remarkable conclusion. Was it that they honestly believed that an aircraft impacting a fog-shrouded hill was proof of its crew's negligence, or might it have been a way of hiding the fog-shrouded evidence that some of their Air-ranking colleagues had pushed an immature aircraft into service?
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Old 31st May 2010, 18:42
  #6429 (permalink)  
 
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Size and Speed

I am aware of the relative lengths of the Sea King and the Chinook. However, comparing their silhouettes I would still say the Chinook is about twice the size of the Sea King. Perhaps bulk is a better word. A champagne flute may be taller than a half pint glass but the latter is bigger.

I am only trying to fathom out a reasonable explanation for the alleged change in speed of the Chinook. It seems very unlikely that it would slow down to 70 knots then accelerate to Vne as it approached the Mull.

If some people believe that this was the case are they trying to say that there was some fault with the engine control system, causing the aircraft to decelerate then accelerate uncontrollably, and that this was the cause of the accident? Perhaps distracting the crew at a critical time?

I think it is much more likely that it would be maintaintaining a steady speed. Perhaps 120 knots - two miles a minute, a very handy speed for navigational purposes, although it may well have been 140 knots.

As a fixed-wing pilot with little rotary experience I would certainly not describe even 140 knots as a dangerously high speed. At that speed the turning radius of any aircraft is very small and the Chinook should have been able to manoeuvre easily at turning points. I am sure someone with more rotary-wing experience will confirm or deny whether this is the case.
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Old 31st May 2010, 23:35
  #6430 (permalink)  
 
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Arthur

I think we will have to disagree over the relative sizes of the two helicopters. However...

If you could share with us the basis upon which you wish to discount the evidence (likely or otherwise?) of the last known witness to see ZD576, perhaps we may be able to progress any theory that may follow?

Perhaps you have other witnesses to the speed of the aircraft, or recordings?

Could the a/c have increased speed shortly before impact? I accept it's possible.

Just show me the evidence that proves it didn't.

Edited to add:
the alleged change in speed of the Chinook
If a witness sees the aircraft at a speed that he assesses as 70kts, and it then impacts a hillside 60secs or so later at high speed, that's not an 'allegation', it is simply a statement of best evidence?
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Old 1st Jun 2010, 07:37
  #6431 (permalink)  
 
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Arthur Rowe

If some people believe that this was the case are they trying to say that there was some fault with the engine control system, causing the aircraft to decelerate then accelerate uncontrollably, and that this was the cause of the accident? Perhaps distracting the crew at a critical time?

Not being a pilot I won't offer opinion, but simply quote the Release to Service which, at the time, warned of ;

Undemanded Flying Control Movement. Very sharp uncommanded inputs to the yaw axis which result in rapid change in aircraft heading in both hover and forward flight................... Aircraft to be landed as soon as practicable

There is no detailed audit trail accompanying this warning, nor should there be in the RTS, but the wording is remarkably similar to the events experienced shortly beforehand by Sqn Ldr Burke, later given in evidence. That is, at the end of a straight run he would experience an UFCM when attempting to execute a turn. I have always thought that a perfect description of what little we know of the final seconds. Notably, Sqn Ldr Burke was actively prevented from giving evidence at the time. Inconvenient to the RO's argument you see.
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Old 1st Jun 2010, 07:57
  #6432 (permalink)  
 
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Arthur Rowe
In my post 6488 I showed that Mr Holbrook was aware of his unfamiliarity with the a/c and would have liked to have seen examples, etc
Further, distance/time analysis by Boeing (not that simulation) has it that they had to have maintained that high cruise speed (over the whole of the leg from Aldergrove to the Mull) to have got there when they did and this did not allow any slowing down anytime as to have dione so would have required the time be made up with excessive (exceeding placard? whatever the term is) speed.
It was not just in the estimation of the a/c's speed that the RAF did not assist Mr Holbrook they did not give him sufficient opportunity to expand on his view of the weather, which he did do in a subsequent inquiry, making it clear that the weather of concern was very much right on the Mull.
I say that they would have been aware of the Mull but judgement of distance to it would have been difficult had they for whatever reason been directly approaching it further, identifying a specific point on it visually would have been almost impossible.
An ear witness on the Mull did not detect any adverse changes in noise that could have made him think that they did anything other than fly straight in.
There is nothing to suggest a control problem.
As I have put forward so often on this thread, there is plenty to suggest that they were approaching a known LZ and were using equipment that, by accident or by design, misled them.
Their turn from 027 to 035 at waypoint change, for which there is evidence that it was deliberate, put them onto the optimum approach line to the LZ (which was right by waypoint A) had they been lined up with it, there was a safe wave-off by means of a moderate banked turn to the left initiated as they crossed the shoreline. Their mis-alignment and over-running the shoreline can be explained by their having refered to a local device that was out of position.
Of course, there are those on this thread who do not want to contemplate this scenario or perhaps see it as their duty to distract others from contemplating it. I think it was Churchill who said something like the truth is so fragile a thing that it needs to be surrounded by a bodyguard of lies the truth in this case must be something very fragile. The families and colleagues of the pilots need to know what really happened so does the British public so however embarrassing or unpalateable a stuffed up exercise may be, how about at least talking about it? Someone must know something sure as hell there was more to this than pilot error or fantastic control jams.
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Old 1st Jun 2010, 07:58
  #6433 (permalink)  
 
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Eyewitness evidence

Unfortunately, even with an eyewitness who is being as honest as he can in his recollection of an event, it has been shown that eyewitness evidence is notoriously unreliable.

There is an interesting article here, among many to be found on the web:

Eyewitness Testimony and Memory: Human Memory is Unreliable and so is Eyewitness Testimony

I quote a short passage from the article.

''Eyewitness testimony is, at best, evidence of what the witness believes to have occurred. It may or may not tell what actually happened. The familiar problems of perception, of gauging time, speed, height, weight, of accurate identification of persons accused of crime all contribute to making honest testimony something less than completely credible.

Prosecutors recognize that eyewitness testimony, even when given in all honesty and sincerity, isnt necessarily credible. Merely because a person claims to have seen something does not mean that what they remember seeing really happened one reason why is that not all eyewitnesses are the same. To simply be a competent witness (competent, which is not the same as credible), a person must have adequate powers of perception, must be able to remember and report well, and must be able and willing to tell the truth.

Thus, such testimony can be critiqued on several grounds: having impaired perception, having impaired memory, having inconsistent testimony, having bias or prejudice, and not having a reputation for telling the truth. If any of those characteristics can be demonstrated, then the competency of the witness is questionable. However, even if none of them apply, that does not automatically mean that the testimony is credible. The fact of the matter is, eyewitness testimony from competent and sincere people has put innocent people in jail.

How can eyewitness testimony become inaccurate? Many factors can come into play: age, health, personal bias and expectations, viewing conditions, perception problems, later discussions with other witnesses, stress, etc.''

Is there a better explanation for the apparent change in speed of the Chinook? If so I would be very glad to hear it and give it due consideration. I do get a feeling that on this thread it is easy to wander into the full half hour of argument rather than five minutes, to quote Monty Python. To further quote:

''An argument is an intellectual process. Contradiction is just the automatic gainsaying anything the other person says.''

''Oh no it isn't''
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Old 1st Jun 2010, 10:50
  #6434 (permalink)  
 
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Walter:
An ear witness on the Mull did not detect any adverse changes in noise that could have made him think that they did anything other than fly straight in.
There is nothing to suggest a control problem.
How on earth would an "ear witness" be able to hear a control problem, Walter? Perhaps he/she should have heard the sounds of the pallet springs becoming detached, as indeed they were found to be at the crash site? Oh, of course they were detached by impact forces alone, weren't they? Weren't they?
Arthur Rowe:
I do get a feeling that on this thread it is easy to wander into the full half hour of argument rather than five minutes, to quote Monty Python.
The only Pythonesque aspect here is to accept any part of a rigged accident investigation as gospel. The reason Mr Holbrook's testimony is so easily disparaged is that there is so little of it. The one and only eye witness available was dealt with and despatched with unseemly haste. The one expert witness to the many technical shortcomings of engine and flight control in the Chinook HC2, Sqn Ldr Burke was not called at all despite putting himself forward for that purpose. Now why would that be I wonder, given that the RAF included such shortcomings in the RTS?
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Old 1st Jun 2010, 18:18
  #6435 (permalink)  
 
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Chugalug
Human hearing is very sensitive to changes in sound.
The lighthouse keeper was a rotorwing enthusiast and had done some light a/c flying, as I understand. He seemed quite sure that there was no change in sound, that they went straight in.
When you watch a helicopter manoeuvre, you will surely note that it can't change much in terms of aspect, power, anything really without your ears picking up the changes in sound.
Are you suggesting that a control jam in a Chinook could have caused a turn (onto a heading that the HP just happened to have set) and allow an unstable a/c to fly over that last leg (waypoint change to impact, a significant length in such an emergency) without any audible sign of the pilot trying to regain control? Fantasy.
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Old 1st Jun 2010, 18:28
  #6436 (permalink)  
 
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Walter, fantasy is believing that some for of covert demonstration went tragically wrong with the whole event being conveniently (and very securely?) covered-up.

Equally, it is somewhat 'fantastic' that the RAF managed to overlook some hideously questionable airworthiness issues when carrying-out its own investigation into the crash.
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Old 1st Jun 2010, 19:25
  #6437 (permalink)  
 
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Are you suggesting that a control jam in a Chinook could have caused a turn (onto a heading that the HP just happened to have set) and allow an unstable a/c to fly over that last leg (waypoint change to impact, a significant length in such an emergency) without any audible sign of the pilot trying to regain control?
Forgive me Walter, but is it not accepted fact that there was no need to execute the turn AT the Waypoint? The point made by Sqn Ldr Burke, denied at the time, was that at the end of a straight run, he had experienced sudden UFCMs when inputting the demand for a turn. And that this sudden change could take him in the opposite direction to that intended.

Could such an UFCM have been a contributory factor? I'll leave that to pilots to discuss. What is certain is that MoD thought it prudent to hide this fact for many years. Just as they concealed the positively dangerous software. It is called misleading by omission. I wonder what an independent inquiry will make of that?
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Old 1st Jun 2010, 19:49
  #6438 (permalink)  
 
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Walter:
When you watch a helicopter manoeuvre, you will surely note that it can't change much in terms of aspect, power, anything really without your ears picking up the changes in sound.
Presumably when you watch, or rather hear in this scenario, such a manoeuvre the changes of sound would come as a result of pilot control inputs. If such inputs cannot be made, because the flight controls are jammed, what changes in sound would you expect to hear? I do not say that this accident happened because the flight controls were jammed, Walter, because I do not know, but you stated that the "Ear Witnesses" heard nothing to suggest a control problem. I simply ask what would they hear if there were one?
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Old 1st Jun 2010, 19:55
  #6439 (permalink)  
 
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The lighthouse keeper was a rotorwing enthusiast and had done some light a/c flying, as I understand. He seemed quite sure that there was no change in sound, that they went straight in.
Although I have a son who flies them, I am not particularly an enthusiast of rotorwings and have done quite a lot of light a/c flying. What I am very familiar with is the sound of Chinooks approaching and passing very low overhead my house, especially late at night. (I love it!!). I would defy anyone who was not an expert to draw any conclusions from the way the sound changes as the aircraft approaches even when in a steady cruise.
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Old 2nd Jun 2010, 12:15
  #6440 (permalink)  
 
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Walter
<p>Their turn from 027 to 035 at waypoint change, for which there is evidence that it was deliberate......</p> <br />
...sorry but there was NO RIGHT TURN after waypoint change.......
..this is a myth started I think by the Fellow from Boeing but few people bother to check his calculations........
..the only evidence for a turn to the right is the Lat.and Long. for the crash site as compared to the Lat.Long. for waypoint change.........but everyone forgets that the numbers for the waypoint change are from the GPS source........
If the A/C were at the absolute , correct and exact Lat.&Long. to WGS84 standard , when the change was made there might be a grain of truth in it ...........but we know that a few seconds later there was a significant GPS offset error of hundreds of metres , guiding them North and East of the true location.
Once we factor this in , plus the offtrack error where they had drifted to right of track (hence the heading of 018 degrees to steer to waypoint 'A' ), which is another 200 feet at least at this range , you will find that flying straight on takes one to the point of impact ...

regards to all on this sad anniversary.........

Robin....
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