Chinook - Hit Back Here
Guest
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I have followed this crash and this thread from the beginning. I appreciate all that has been written. With regard to the most recent responses from the MoD it is relevant to note that they continue to bang on about the independence of the AAIB's investigation. Yet the AAIB did not know the history of problems regarding FADEC, and they did not have access to black box recorders despite the money being voted by the Treasury in May 1988 for their installation in Chinooks. Essentially the AAIB worked within the confines that they were directed towards by the MoD "experts". Why is it then that the AAIB did not appreciate what it meant to find a code 5 fault within the one surviving DECU of ZD576. This anomaly in a flight critical piece of software should never exist, it was subsequently discovered. To the AAIB (and presumably to the BoI president) it was a true revelation.
But because the information came from MoD files, the Ministry decided the information was not new evidence.
It is this mindset that must be conquered.
But because the information came from MoD files, the Ministry decided the information was not new evidence.
It is this mindset that must be conquered.
Guest
Posts: n/a
Keep up the good work folks. There will be no suprises in any of you replies, but the MoD are getting seriously hacked off with the bigger post bags!
Stik,
I'll give you some ideas in a few days after I have had time to sit down and think (Well, there's a first for everything!!)
X-Quork,
The information was taken from the survivable memory. Only tells you what they did, not what they were doing. The BoI to this accident made reference that they were hampered by the lack of CVR and ADR. The Board also noted that recommendations to fit CVR and ADR were made by Boards from 1987 and 1988. I have pointed this fact out to the PM in my letter, of which no reply received yet.
1.3VStall,
Yep, agree entirely.
antennae,
Welcome to the debate. Despite a thorough investgation and report by the AAIB, FADEC was a recent innovation to them. It was not fully understood at the time. I do, however, think the AAIB were thoroughly professional in their task.
Believe it or not, FADEC was not considered flight safety critical. I think I am right in recalling that someone in the MoD said in a written statement that "Boeing did not consider the FADEC to be flight safety critical because the engines on the Chinook are not considered safety critical". (This bit taken from the Computer Weekly report).
Bizzare if you ask me, but that's what we're up against.
GICASI
Again, I agree. It seems that there's one rule for us and another for them.
Thanks everyone for the continued support.
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
[This message has been edited by Brian Dixon (edited 05 January 2001).]
Stik,
I'll give you some ideas in a few days after I have had time to sit down and think (Well, there's a first for everything!!)
X-Quork,
The information was taken from the survivable memory. Only tells you what they did, not what they were doing. The BoI to this accident made reference that they were hampered by the lack of CVR and ADR. The Board also noted that recommendations to fit CVR and ADR were made by Boards from 1987 and 1988. I have pointed this fact out to the PM in my letter, of which no reply received yet.
1.3VStall,
Yep, agree entirely.
antennae,
Welcome to the debate. Despite a thorough investgation and report by the AAIB, FADEC was a recent innovation to them. It was not fully understood at the time. I do, however, think the AAIB were thoroughly professional in their task.
Believe it or not, FADEC was not considered flight safety critical. I think I am right in recalling that someone in the MoD said in a written statement that "Boeing did not consider the FADEC to be flight safety critical because the engines on the Chinook are not considered safety critical". (This bit taken from the Computer Weekly report).
Bizzare if you ask me, but that's what we're up against.
GICASI
Again, I agree. It seems that there's one rule for us and another for them.
Thanks everyone for the continued support.
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
[This message has been edited by Brian Dixon (edited 05 January 2001).]
Guest
Posts: n/a
The AAIB work is beyond reproach. My concern lies with the fact the tremendous work of the AAIB had to be based on so much guidance from the MoD. I am also firmly of the view no new evidence is necessary. What more does the MoD need than is already contained within the AAIB report and BoI? There are a host of potential problems and none as complicated as FADEC - the debonding incidents of the flight control pallets, the ENG Fail caption lights whose accuracy could not be guaranteed for up to 12 secs etc. How though, in precise terms, do we move the fight on? I have only joined this debate here because we need to develop a new strand of thought. Repetition by letter of already known facts to civil servants is of limited use. I concede, however, that I am at a loss as to how to move it forward. Bigger brains please intervene.
Guest
Posts: n/a
bad livin'
I think the BoI rules have now changed so that they do not apportion blame. They look at the cause of any accident and seek to use any findings for future air safety.
In this particular accident, no blame was allocated to either Graham or Kevin.
Funnily enough, the Board felt that it would be incorrect to blame the pilots for human failings too. It just lost it's way higher up the chain.
Hope that helps.
Safe flying
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
I think the BoI rules have now changed so that they do not apportion blame. They look at the cause of any accident and seek to use any findings for future air safety.
In this particular accident, no blame was allocated to either Graham or Kevin.
Funnily enough, the Board felt that it would be incorrect to blame the pilots for human failings too. It just lost it's way higher up the chain.
Hope that helps.
Safe flying
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
Guest
Posts: n/a
Listening to the MoD statement on the effects of DU shells in FRY and the Gulf:
"We are approaching this problem with an open mind...
"If new evidence comes forward..."
Yada yada yada...
A case of aural deja vu? Can I have a job in MoD PR? - Spout the same old cr@p whatever 'problem' comes up. I think they have it on a tape and just press play!
Ho, hum!
"We are approaching this problem with an open mind...
"If new evidence comes forward..."
Yada yada yada...
A case of aural deja vu? Can I have a job in MoD PR? - Spout the same old cr@p whatever 'problem' comes up. I think they have it on a tape and just press play!
Ho, hum!
Guest
Posts: n/a
"... the Board felt that it would be incorrect to blame the pilots for human failings too"
Am I missing something here, but how can anyone blame the pilots if the board of inquiry states the above? I'll delete this post if I have missed something and therefore I'm talking bollox.
Am I missing something here, but how can anyone blame the pilots if the board of inquiry states the above? I'll delete this post if I have missed something and therefore I'm talking bollox.
Guest
Posts: n/a
Brian,
Here are the questions to put to the AOC and CinC:
Q. ‘Exactly what happened, second by second, in the cockpit in the final 60 seconds of the flight?’
A. ‘we do not know’. [FACT]
Q. ‘Do you know if something catastrophic occurred in the cockpit or to the aircraft during the final 60 seconds (YES or NO)?’
A. ‘No.’ [FACT]
Q. ‘If something catastrophic had occurred, can you guarantee that either pilot had the skill to deal with the emergency?’
A. ‘No.’ [FACT]
Q. ‘In view of this, can you categorically, and without error, conclude that the pilots were negligent?’
A. ‘No.’ [FACT]
I fear that this case is going to have to go to court the clear the guys’ names. (Thinks...MOD has the habit of settling before going to trial - just as you go to open the courtroom door, the MOD legal team rushes forward and makes you an offer you can't refuse...)
[This message has been edited by FJJP (edited 07 January 2001).]
Here are the questions to put to the AOC and CinC:
Q. ‘Exactly what happened, second by second, in the cockpit in the final 60 seconds of the flight?’
A. ‘we do not know’. [FACT]
Q. ‘Do you know if something catastrophic occurred in the cockpit or to the aircraft during the final 60 seconds (YES or NO)?’
A. ‘No.’ [FACT]
Q. ‘If something catastrophic had occurred, can you guarantee that either pilot had the skill to deal with the emergency?’
A. ‘No.’ [FACT]
Q. ‘In view of this, can you categorically, and without error, conclude that the pilots were negligent?’
A. ‘No.’ [FACT]
I fear that this case is going to have to go to court the clear the guys’ names. (Thinks...MOD has the habit of settling before going to trial - just as you go to open the courtroom door, the MOD legal team rushes forward and makes you an offer you can't refuse...)
[This message has been edited by FJJP (edited 07 January 2001).]
Guest
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FJJP
Unfortunately, the Courts are probably not an option. Under Scots Law there is no reason to challenge Sir Stephen Young's FAI since he came to the same view we have come to. In Scotland it is Sir Stephen Young's verdict that counts, whatever some 10-a-penny (and hardly independent or objective) Air Marshals may have said.
AFAIK there is no English law under which Wrotten can be challenged in England.
[This message has been edited by misterploppy (edited 07 January 2001).]
Unfortunately, the Courts are probably not an option. Under Scots Law there is no reason to challenge Sir Stephen Young's FAI since he came to the same view we have come to. In Scotland it is Sir Stephen Young's verdict that counts, whatever some 10-a-penny (and hardly independent or objective) Air Marshals may have said.
AFAIK there is no English law under which Wrotten can be challenged in England.
[This message has been edited by misterploppy (edited 07 January 2001).]
Guest
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FJJP,
Good questions, and ones that have been asked many a time. The answer given is one of, "Well the wreckeage suggests that there was nothing wrong with the aircraft, so it must have been some other reason."
It doesn't seem to matter to certain individuals that the final 20 odd seconds are unaccounted for, or that 20 odd per cent of the airframe was never recovered from the crash site.
This WILL go on until justice prevails.
Thud & Blunder, would you drop me an e-mail??
Regards all
Brian
[email protected]
"Justice has no expiry date" - John Cook
Good questions, and ones that have been asked many a time. The answer given is one of, "Well the wreckeage suggests that there was nothing wrong with the aircraft, so it must have been some other reason."
It doesn't seem to matter to certain individuals that the final 20 odd seconds are unaccounted for, or that 20 odd per cent of the airframe was never recovered from the crash site.
This WILL go on until justice prevails.
Thud & Blunder, would you drop me an e-mail??
Regards all
Brian
[email protected]
"Justice has no expiry date" - John Cook
Guest
Posts: n/a
Tim C,
You have not missed anything. The Board conclusion for each pilot was as follows:
Jon Tapper
"The Board was unable to positively determine the sequence of events leading up to the accident, and therefore concluded that although it is likely that Flt Lt Tapper made an Error of Judgement in the conduct of the attempted climb over the Mull of Kintyre, it would be incorrect to criticise him for human failings based on the available evidence."
Rick Cook
"Flt Lt Cook could not be criticised for failing to identify any errors. The Board concluded that there were no human failings with Flt Lt Cook."
Now, where is there a reference to Gross Negligence? Maybe it is just me that is missing something.
Still looking to join up??
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
You have not missed anything. The Board conclusion for each pilot was as follows:
Jon Tapper
"The Board was unable to positively determine the sequence of events leading up to the accident, and therefore concluded that although it is likely that Flt Lt Tapper made an Error of Judgement in the conduct of the attempted climb over the Mull of Kintyre, it would be incorrect to criticise him for human failings based on the available evidence."
Rick Cook
"Flt Lt Cook could not be criticised for failing to identify any errors. The Board concluded that there were no human failings with Flt Lt Cook."
Now, where is there a reference to Gross Negligence? Maybe it is just me that is missing something.
Still looking to join up??
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
Guest
Posts: n/a
In March 1995 I was posted at short notice to HQ1Gp as FS(Flight Safety)1. The job spec called for either Fast Jet or SH experience of which I had neither (apart from half an hour in a Gazelle with Buck Rowlands circa 1980). It is, of course, entirely possible that this (the posting - not Buck!!) played some part in my decision to opt for the 1996 redundancy scheme.
The BOI into the Chinook accident was in the process of being Staffed when I arrived. To try to get a feel for the job I read this BOI in great detail, and repeatedly, over many weeks. It is now some 5 years since I had access to this BOI so I hope my memory is still as accurate as it used to be. I will, however, try to answer some of the points and queries that have been raised on this thread.
It was Sir Malcom Rifkind who decided that BOI's could be released to next of kin if they so requested. The only caveats were that the BOI would be reduced to RESTRICTED security level by deletion of any information with a higher classification and that any matter that could be disturbing (photos or descriptions of injuries etc) would be handed over in a sealed package with the advice that the next of kin should not open it by themselves.
In the case of ZD576 it was decided at Ministerial level that copies of the BOI woiuld be given to all Next of Kin simultaneously.
It is not "unprecedented" for the Convening Officer to overrule the findings of the BOI. In fact in 2 other BOI's that were running concurrently with this one (it was a bad year-there were actually 5 on the go at that time) the findings were changed and 2 crews who had been found negligent by the BOI's were exoneratd and pilots who had been left alone by a BOI were found to be negligent by their respective AOC's.
It has been suggested that the Pilots must have been specially chosen for this task. The truth is that this was a detatchment and the Pilots chose themselves - they were the outgoing Detatchment Commander and the incoming Detatchment Commander. They also chose to do all the tasking that day to give the other crew a day off. The BOI decided that there was no administrative reason to preclude this. Whether this was a judicious use of resources is another matter.
"The aircraft returned from an early morning sortie with engine problems and suffering from UFCM's." This is just blatent Press speculation. If this were true it would mean that all the engineering and Flight Authorisation documentation was removed and substituted before the BOI could inspect it; and that all those who gave evidence to the BOI on these aspects lied on oath. The evidence is that the aircraft and crew performed some five and a half hours of internal tasking prior to the final sortie and that the aircraft was given a normal turnround servicing. The only abnormal aspect was that Flt Lt Tapper asked an avionics tradesman to look at the GPS which had been losing signal. The tradesman found no fault.
One of the first things that is taught in Flying Training is that if you are flying below Transition Altitude then you set the regional QNH on the subscale of your altimeter unless you are on approach to an airfield when you set the Airfield QNH or QFE as directed. The AAIB investigation into the crash of ZD576 showed that the Right Hand altimeter was so set but the left hand altimeter was some 10mb lower. There was no evidence that this setting had been altered by the crash. The BOI speculated that it could have been set on Aldergrove QFE.
The Rad Alt warnings were not set in accordance with the SOP. One was set above cruising altitude and the other at minimum where it would have given little, if any, warning of impact with the ground. Again there was no indication that these settings had been altered by the impact.
Several people have criticised Sir William Wratton for saying that the crew should have climbed to their SALT of 2800ft when the true SALT was considerably higher. Much as I regret having to agree with the criticism of a Senior Officer (and I nearly had a straight face as I typed that)I have to accept that he was in error in this case. What he should have said (and possibly meant to say) was that they should have climbed to their CALCULATED SALT of 2800ft. The BOI included a copy of the route chart that had been left with the authorisation sheets. On this chart their planned SALT for the leg Aldergrove to the Mull is clearly shown as 2800ft and their planned cruise speed as 120kts. In fact, on their entire route to Inverness there was not a single planned SALT that took into account the proximity of Ben Nevis. A climb to 2800ft would have meant that they cleared the Mull by 1000ft. I appreciate the problem of the icing level but,if they went into cloud inadvertantly, the possibility of icing has got to be a better option than the probability of impact with the ground.
The distance between Aldergrove and the Mull is approx 43NM in a straight line. To travel this distance in 17 mins gives an average groundspeed of 152kts. Because of the time needed to accelerate the cruise groundspeed would be higher. They did not, however, travel in a straight line; departing initially to the east and transiting overland at very low altitude. It is likely that actual track mileage was about 46NM which would give an average groundspeed of 162kts. The VFR requirements for a Military Helicopter with a groundspeed of 155kts or greater were 5km visibility and 1000ft vertical seperation from cloud.
Several people have quoted the Yachtsman who saw the Chinook approx 2 miles from the Mull. It is my recollection that his evidence was that he saw the Chinook flying "in good visibility just below the cloudbase".
The people on the Mull all reported that the weather was foggy. All heard, but did not see, the helicopter (with the possible exception of the wife of the Lighthouse keeper who stated that she thought she saw the lower red anti-collision beacon but may have imagined it because she would have expected to see one--there is a landing pad close to the Lighthouse). Moreover, there was video evidence taken about 10mins before the crash. This was analysed at Wyton and the visibility at that time assessed as approx 400 metres. The computer projection of the final flight path assessed that the aircraft pitched up 440 metres before impact at an IAS of 150kts.
The evidence in the BOI shows that prior to the crash the aircraft was being flown under VFR in IFR conditions with one barometric altimeter subscale and both rad alt warnings incorrectly set and on a flight plan with incorrectly calculated SALTs.
I know that many will disagree with me but I have to conclude that the findings of the AOC and CinC were justified.
Brian, please feel free to e-mail me if you wish.
I will now retire to await the incoming (and possibly the thought police for breach of the Official Secrets Act)
Oh, If CAS DOES read this then maybe he would like to get his ADC to give me a ring because I think that there may be a way to solve this issue once and for all. Innsworth have my number.
The BOI into the Chinook accident was in the process of being Staffed when I arrived. To try to get a feel for the job I read this BOI in great detail, and repeatedly, over many weeks. It is now some 5 years since I had access to this BOI so I hope my memory is still as accurate as it used to be. I will, however, try to answer some of the points and queries that have been raised on this thread.
It was Sir Malcom Rifkind who decided that BOI's could be released to next of kin if they so requested. The only caveats were that the BOI would be reduced to RESTRICTED security level by deletion of any information with a higher classification and that any matter that could be disturbing (photos or descriptions of injuries etc) would be handed over in a sealed package with the advice that the next of kin should not open it by themselves.
In the case of ZD576 it was decided at Ministerial level that copies of the BOI woiuld be given to all Next of Kin simultaneously.
It is not "unprecedented" for the Convening Officer to overrule the findings of the BOI. In fact in 2 other BOI's that were running concurrently with this one (it was a bad year-there were actually 5 on the go at that time) the findings were changed and 2 crews who had been found negligent by the BOI's were exoneratd and pilots who had been left alone by a BOI were found to be negligent by their respective AOC's.
It has been suggested that the Pilots must have been specially chosen for this task. The truth is that this was a detatchment and the Pilots chose themselves - they were the outgoing Detatchment Commander and the incoming Detatchment Commander. They also chose to do all the tasking that day to give the other crew a day off. The BOI decided that there was no administrative reason to preclude this. Whether this was a judicious use of resources is another matter.
"The aircraft returned from an early morning sortie with engine problems and suffering from UFCM's." This is just blatent Press speculation. If this were true it would mean that all the engineering and Flight Authorisation documentation was removed and substituted before the BOI could inspect it; and that all those who gave evidence to the BOI on these aspects lied on oath. The evidence is that the aircraft and crew performed some five and a half hours of internal tasking prior to the final sortie and that the aircraft was given a normal turnround servicing. The only abnormal aspect was that Flt Lt Tapper asked an avionics tradesman to look at the GPS which had been losing signal. The tradesman found no fault.
One of the first things that is taught in Flying Training is that if you are flying below Transition Altitude then you set the regional QNH on the subscale of your altimeter unless you are on approach to an airfield when you set the Airfield QNH or QFE as directed. The AAIB investigation into the crash of ZD576 showed that the Right Hand altimeter was so set but the left hand altimeter was some 10mb lower. There was no evidence that this setting had been altered by the crash. The BOI speculated that it could have been set on Aldergrove QFE.
The Rad Alt warnings were not set in accordance with the SOP. One was set above cruising altitude and the other at minimum where it would have given little, if any, warning of impact with the ground. Again there was no indication that these settings had been altered by the impact.
Several people have criticised Sir William Wratton for saying that the crew should have climbed to their SALT of 2800ft when the true SALT was considerably higher. Much as I regret having to agree with the criticism of a Senior Officer (and I nearly had a straight face as I typed that)I have to accept that he was in error in this case. What he should have said (and possibly meant to say) was that they should have climbed to their CALCULATED SALT of 2800ft. The BOI included a copy of the route chart that had been left with the authorisation sheets. On this chart their planned SALT for the leg Aldergrove to the Mull is clearly shown as 2800ft and their planned cruise speed as 120kts. In fact, on their entire route to Inverness there was not a single planned SALT that took into account the proximity of Ben Nevis. A climb to 2800ft would have meant that they cleared the Mull by 1000ft. I appreciate the problem of the icing level but,if they went into cloud inadvertantly, the possibility of icing has got to be a better option than the probability of impact with the ground.
The distance between Aldergrove and the Mull is approx 43NM in a straight line. To travel this distance in 17 mins gives an average groundspeed of 152kts. Because of the time needed to accelerate the cruise groundspeed would be higher. They did not, however, travel in a straight line; departing initially to the east and transiting overland at very low altitude. It is likely that actual track mileage was about 46NM which would give an average groundspeed of 162kts. The VFR requirements for a Military Helicopter with a groundspeed of 155kts or greater were 5km visibility and 1000ft vertical seperation from cloud.
Several people have quoted the Yachtsman who saw the Chinook approx 2 miles from the Mull. It is my recollection that his evidence was that he saw the Chinook flying "in good visibility just below the cloudbase".
The people on the Mull all reported that the weather was foggy. All heard, but did not see, the helicopter (with the possible exception of the wife of the Lighthouse keeper who stated that she thought she saw the lower red anti-collision beacon but may have imagined it because she would have expected to see one--there is a landing pad close to the Lighthouse). Moreover, there was video evidence taken about 10mins before the crash. This was analysed at Wyton and the visibility at that time assessed as approx 400 metres. The computer projection of the final flight path assessed that the aircraft pitched up 440 metres before impact at an IAS of 150kts.
The evidence in the BOI shows that prior to the crash the aircraft was being flown under VFR in IFR conditions with one barometric altimeter subscale and both rad alt warnings incorrectly set and on a flight plan with incorrectly calculated SALTs.
I know that many will disagree with me but I have to conclude that the findings of the AOC and CinC were justified.
Brian, please feel free to e-mail me if you wish.
I will now retire to await the incoming (and possibly the thought police for breach of the Official Secrets Act)
Oh, If CAS DOES read this then maybe he would like to get his ADC to give me a ring because I think that there may be a way to solve this issue once and for all. Innsworth have my number.
Guest
Posts: n/a
Hi K52. Welcome to the thread.
Your power of recall is very impressive. There is little, if anything in your post for me to argue with.
However, it still does not convince me that there is absolutely no doubt whatsoever. The AAIB report noted that the No 1 DECU was unreadable. It stated that around 20% of the aircraft was totally destroyed. It stated that although there was no evidence, the possibility of control system jam could not be positively dismissed. It also stated that the pre-impact serviceability of the aircraft could not be positively verified. There are also several more examples that I could offer here but I shall spare you my typing.
I also accept that you may be entirely correct in your assumption and support of the reviewing officers findings. But, in order to find deceased aircrew guilty of negligence, there has to be absolutely no doubt whatsoever. The comments by the AAIB are enough to introduce that doubt, however small, and therefore negate and invalidate the reviwing officer's verdict.
It may be that Rick and Jon made a mistake, but as it stands, there is not the absolute proof necessary to support the current verdict. That is why it should be withdrawn immediately.
Can't see how you have breached the OSA and hope you don't get bombarded with unpleasant responses.
I'm certainly not the CAS but would be interested in hearing your proposal for a solution. Would you be willing to drop me an e-mail??
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
Your power of recall is very impressive. There is little, if anything in your post for me to argue with.
However, it still does not convince me that there is absolutely no doubt whatsoever. The AAIB report noted that the No 1 DECU was unreadable. It stated that around 20% of the aircraft was totally destroyed. It stated that although there was no evidence, the possibility of control system jam could not be positively dismissed. It also stated that the pre-impact serviceability of the aircraft could not be positively verified. There are also several more examples that I could offer here but I shall spare you my typing.
I also accept that you may be entirely correct in your assumption and support of the reviewing officers findings. But, in order to find deceased aircrew guilty of negligence, there has to be absolutely no doubt whatsoever. The comments by the AAIB are enough to introduce that doubt, however small, and therefore negate and invalidate the reviwing officer's verdict.
It may be that Rick and Jon made a mistake, but as it stands, there is not the absolute proof necessary to support the current verdict. That is why it should be withdrawn immediately.
Can't see how you have breached the OSA and hope you don't get bombarded with unpleasant responses.
I'm certainly not the CAS but would be interested in hearing your proposal for a solution. Would you be willing to drop me an e-mail??
Regards
Brian
[email protected]
"Justice has no expiry date" - John Cook
Guest
Posts: n/a
K52 First of many incoming I must be quick as I am in a hurry.
1 The VFR rules apply to airspeed and not groundspeed. The rules were clear of cloud in sight of surface.
2 SALT was 5900ft based on Ben Nevis. The Chinook icing clearence of +4 degC allowed a climb to 2500, not even enough for the local calculated value of 2800'
You do not know what occurred in the last moments of ZD576's flight, so just like all of us and Wratten too, you do not have the evidence to find the pilots guilty of gross negligence 'beyond any doubt whatsoever'
You indeed show your lack of SH experience, in the same way as Wratten did his!
1 The VFR rules apply to airspeed and not groundspeed. The rules were clear of cloud in sight of surface.
2 SALT was 5900ft based on Ben Nevis. The Chinook icing clearence of +4 degC allowed a climb to 2500, not even enough for the local calculated value of 2800'
You do not know what occurred in the last moments of ZD576's flight, so just like all of us and Wratten too, you do not have the evidence to find the pilots guilty of gross negligence 'beyond any doubt whatsoever'
You indeed show your lack of SH experience, in the same way as Wratten did his!
Guest
Posts: n/a
Couldn't agree more Arkroyal. Worth remembering that Fl. Lt. Tapper had been told shortly before the accident by a superior officer that any pilot who broke the icing clearance rules relating to the Mk2 would be held personally liable. Within that less than helpful culture, therefore, the crew would not have considered an overfly of the Mull - especially when a transit over water, first to Corran and then up the Great Glen, would have taken ZD576 to its destination at Fort George. And had the weather deteriorated to such an extent that the crew felt they were in danger of being outside VFR, they should have been able to either stop and find another way through or turn back.
Guest
Posts: n/a
ARK ROYAL
Sorry, that salvo was over. You have based your calculations on a standard lapse rate of 2 degrees C /1000ft (actually its 1.98 degrees C /1000ft up to a height of 36090 ft above which the temperature is assumed to remain constant at minus 56.5 degrees C - I claim my merit star). What was the actual lapse rate that day - was there a temperature inversion? I would still say thay the POSSIBILITY of icing is a better bet than the PROBABILITY of impact with the ground!!
In addition, as you should know, the Military make up their own rules; it is therefore THEIR rules regarding VFR flight that we should take into account. It is, of course, possible that No1 Aeronautical Information Documents Unit made a complete B*lls up regarding VFR for military helicopters but, on the assumption that they didn't,then the requirement for Military Helicopters to fly VFR at a GROUNDSPEED of greater than 155 kts was 1000 ft vertical separation from cloud.
Sorry, that salvo was over. You have based your calculations on a standard lapse rate of 2 degrees C /1000ft (actually its 1.98 degrees C /1000ft up to a height of 36090 ft above which the temperature is assumed to remain constant at minus 56.5 degrees C - I claim my merit star). What was the actual lapse rate that day - was there a temperature inversion? I would still say thay the POSSIBILITY of icing is a better bet than the PROBABILITY of impact with the ground!!
In addition, as you should know, the Military make up their own rules; it is therefore THEIR rules regarding VFR flight that we should take into account. It is, of course, possible that No1 Aeronautical Information Documents Unit made a complete B*lls up regarding VFR for military helicopters but, on the assumption that they didn't,then the requirement for Military Helicopters to fly VFR at a GROUNDSPEED of greater than 155 kts was 1000 ft vertical separation from cloud.
Guest
Posts: n/a
K52,
Re your first paragraph in reply to Arkroyal, it is possible (all conjecture, like the Air Marshals' findings..) that it wasn't icing the crew were bothered about when they strove to maintain VFR Low Level. As you'll have seen in earlier posts, the point was that to go into any temp below plus 4 deg C was outside the Release to Service at that time, and the Chinook force had been specifically told beforehand that any deviation from R to S was something the pilots could be held personally liable for. Neat trick - make an exceptionally difficult set of limitations when applied to real-world tasking, then absolve the organisation of any responsibility when it all goes pear-shaped.
In the RAF SH world, as with the RN and the AAC, no-one relies entirely on a weather-guessers forecast. However, there was probably no point in including Ben Nevis in the S Alt calcs as it would obviously have been so far into the minus on the Celsius scale as to make it an impossible option within the constraints mentioned above.
However, none of this detracts from the point made so well by people more erudite than me: where is the certain knowledge that the pilots were negligent? Nowhere - so why does the unjust verdict still stand?
Re your first paragraph in reply to Arkroyal, it is possible (all conjecture, like the Air Marshals' findings..) that it wasn't icing the crew were bothered about when they strove to maintain VFR Low Level. As you'll have seen in earlier posts, the point was that to go into any temp below plus 4 deg C was outside the Release to Service at that time, and the Chinook force had been specifically told beforehand that any deviation from R to S was something the pilots could be held personally liable for. Neat trick - make an exceptionally difficult set of limitations when applied to real-world tasking, then absolve the organisation of any responsibility when it all goes pear-shaped.
In the RAF SH world, as with the RN and the AAC, no-one relies entirely on a weather-guessers forecast. However, there was probably no point in including Ben Nevis in the S Alt calcs as it would obviously have been so far into the minus on the Celsius scale as to make it an impossible option within the constraints mentioned above.
However, none of this detracts from the point made so well by people more erudite than me: where is the certain knowledge that the pilots were negligent? Nowhere - so why does the unjust verdict still stand?