Chinook - Still Hitting Back 3 (Merged)
Just a numbered other
By the way, you still have not answered my question!!! JP
Ask me a question, I'll try to answer it.
What made them go away? After 15 years I would imagine that even in a safety critical component such as this (ie if it ain't bust don't fix it) there would be redesign, revision and update.
The code was rewritten...for the fadec software. Everyone flying the ch47 knows that....
The Rev 1 version software only removed the spurious Eng Fail caption by reducing the sensitivity of the routine - that's it!
It's a bit of a puzzle isn't it, C240? Faulty code leading to uncommanded engine run downs, run ups, shut downs as well as spurious failure warnings, and misleading and confusing indications. Rev1 deals only with "spurious Eng Fail caption" (thanks for that info), yet all the rest seem to have gone now as well! Perhaps if we apply a bit of CRM and trouble shooting we might narrow down the possibilities. Did the other problems disappear before, coincident with, or after Rev1? How does it look from your seat? Or is the answer a Homer like shrug and "Yea, well what can you do?" Any ideas? Anyone?
Chug,
Thats my point, you automatically link the software with the 'engine run downs, run ups, shut downs as well as spurious failure warnings, and misleading and confusing indications'. As Brian kindly reprinted from the EDS Scicon report:
How does it look from my seat? I'm still as happy to fly the Chinook today as I was in 1994. Like many others.
Thats my point, you automatically link the software with the 'engine run downs, run ups, shut downs as well as spurious failure warnings, and misleading and confusing indications'. As Brian kindly reprinted from the EDS Scicon report:
A category one anomaly indicates an actual coding error or non-compliance with the documentation. However this does not mean that it necessarily has any safety implications, it may not even affect the overall operation of the system.
Last edited by chinook240; 21st Apr 2009 at 08:29.
Just a numbered other
JP:
Bit of a loaded question then, JP.
If the intention was to scrape over the hills with 200ft to spare, by being 500 yds left, then we would indeed be looking at a
and I'd have to agree.
Such a plan is incredible. Ludicrous.
I think I answered you before.
What actually occurred to prevent the most likely plan (to turn left along the coast at low level in VMC) will never be known.
Forget about assumed tracks and so on, but can we also agree that if the a/c had been about 500 yds to the left, (confusion between lighthouse compound and fog signal compound?- just a theory) it would have cleared the hill ahead with around 200 ft to spare, and no-one would then ever have known about this most greivous breach of airmanship ie flying blind over hills?
If the intention was to scrape over the hills with 200ft to spare, by being 500 yds left, then we would indeed be looking at a
most greivous breach of airmanship ie flying blind over hills
Such a plan is incredible. Ludicrous.
I think I answered you before.
What actually occurred to prevent the most likely plan (to turn left along the coast at low level in VMC) will never be known.
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Hi Chug,
at this present time, the primary goal for the Campaign is to secure the removal of the unsustainable slur against Rick and Jon, and for the words 'Gross Negligence' to be permanently removed from their record.
I also agree that any lasting legacy should not be in their names, but in the names of all who made the ultimate sacrifice due to the cost cutting efforts of others. I would suggest that that particular campaign should be orchestrated by someone with more influence than individuals such as me. I would hope that, perhaps, a body such as the National Audit Office or a brave Member of Parliament might take up that baton. I have said, before, that I would like to hang up my 'irritating' boots once Rick and Jon's names have been cleared, but would willingly support anyone who would seek to ensure a more robust and transparent airworthiness procedure.
I have already made comment to one, or two, influential people in respect of airworthiness and introduction into service of equipment in the hope that they will take the matter forward at some point.
Chinook 240,
thank you for the up to date information in relation to FADEC, and the limited rewrite. Interesting that you say that The Rev 1 version software only removed the spurious Eng Fail caption by reducing the sensitivity of the routine. Are you aware that on 17 May 1994, ZD576 had the Emergency Power Caption light illuminate three times, indicating an engine problem, and on 25 May 1994, the Master Warning Signal was activated, indicating that the Nº2 (right hand side) engine was about to fail? Spurious, or not, I'm sure this would be quite distracting.
Perhaps, encompassing everybody's theory (and being slightly fanciful), the crew had just made the waypoint change when a spurious Eng Fail caption light came on, the crew then made a slight turn to the right to make landfall for an emergency landing and, due to the distraction, hit the Mull. I can't prove that to be correct (and actually doubt it to be correct), but there is no-one who can actually prove it wrong, based upon what little evidence is known. Absolutely no doubt whatsoever? I don't think so.
I'm also very grateful that you continue to fly Chinooks. You, and your colleagues are doing a magnificent job and deserve the thanks of the Nation. I hope that by being as irritating as I am, and making the MoD be more careful about what they release into service, I am still doing my bit too.
Mr Purdey,
Why do you continually press for answers, yet offer none in return? Hardly cricket, is it?
My best, as always.
Brian
"Justice has no expiry date" - John Cook
at this present time, the primary goal for the Campaign is to secure the removal of the unsustainable slur against Rick and Jon, and for the words 'Gross Negligence' to be permanently removed from their record.
I also agree that any lasting legacy should not be in their names, but in the names of all who made the ultimate sacrifice due to the cost cutting efforts of others. I would suggest that that particular campaign should be orchestrated by someone with more influence than individuals such as me. I would hope that, perhaps, a body such as the National Audit Office or a brave Member of Parliament might take up that baton. I have said, before, that I would like to hang up my 'irritating' boots once Rick and Jon's names have been cleared, but would willingly support anyone who would seek to ensure a more robust and transparent airworthiness procedure.
I have already made comment to one, or two, influential people in respect of airworthiness and introduction into service of equipment in the hope that they will take the matter forward at some point.
Chinook 240,
thank you for the up to date information in relation to FADEC, and the limited rewrite. Interesting that you say that The Rev 1 version software only removed the spurious Eng Fail caption by reducing the sensitivity of the routine. Are you aware that on 17 May 1994, ZD576 had the Emergency Power Caption light illuminate three times, indicating an engine problem, and on 25 May 1994, the Master Warning Signal was activated, indicating that the Nº2 (right hand side) engine was about to fail? Spurious, or not, I'm sure this would be quite distracting.
Perhaps, encompassing everybody's theory (and being slightly fanciful), the crew had just made the waypoint change when a spurious Eng Fail caption light came on, the crew then made a slight turn to the right to make landfall for an emergency landing and, due to the distraction, hit the Mull. I can't prove that to be correct (and actually doubt it to be correct), but there is no-one who can actually prove it wrong, based upon what little evidence is known. Absolutely no doubt whatsoever? I don't think so.
I'm also very grateful that you continue to fly Chinooks. You, and your colleagues are doing a magnificent job and deserve the thanks of the Nation. I hope that by being as irritating as I am, and making the MoD be more careful about what they release into service, I am still doing my bit too.
Mr Purdey,
Why do you continually press for answers, yet offer none in return? Hardly cricket, is it?
My best, as always.
Brian
"Justice has no expiry date" - John Cook
Last edited by Brian Dixon; 21st Apr 2009 at 15:43.
Chinook HC2 Airworthiness
C240, thank you for your reply. I am glad that you are as happy as ever to fly the Chinook. I share Brian Dixon's gratitude and admiration for what you and your colleagues achieve with that aircraft. If the Huey was the archetypal image of aviation in Vietnam, then surely the Chinook is that for Iraq and Afghanistan?
There would appear to be an enormous improvement in Engine Control reliability these days compared to when the HC2 first entered service. As you rightly say this might not be down to initially faulty software in the DECU that controls the FADEC fuel scheduling, thus determining engine power whether demanded or not. Like Inspector Clouseau I suspect no one yet I suspect everyone, but I have what my old CRM manual called a "High Incidence of Suspicion" about that software. Brian reminds us that in under 20% of the software EDS Scicon found a total of 485 anomalies alone of varying categories. BD wanted a rewrite. CA had only granted a restricted RTS. Is it possible that before a full RTS was granted that rewrite happened, clearing out all the recurring malfunctions and hence the need for the restricted RTS, with the exception of the spurious Eng Fail caption that was removed by Rev1 to that rewrite? Presumably the whole point of BD checking, or having checked, the software is to correct/rewrite faulty code. Once it passes their analysis and is accepted the subsequent revisions would start from there, wouldn't they?
There would appear to be an enormous improvement in Engine Control reliability these days compared to when the HC2 first entered service. As you rightly say this might not be down to initially faulty software in the DECU that controls the FADEC fuel scheduling, thus determining engine power whether demanded or not. Like Inspector Clouseau I suspect no one yet I suspect everyone, but I have what my old CRM manual called a "High Incidence of Suspicion" about that software. Brian reminds us that in under 20% of the software EDS Scicon found a total of 485 anomalies alone of varying categories. BD wanted a rewrite. CA had only granted a restricted RTS. Is it possible that before a full RTS was granted that rewrite happened, clearing out all the recurring malfunctions and hence the need for the restricted RTS, with the exception of the spurious Eng Fail caption that was removed by Rev1 to that rewrite? Presumably the whole point of BD checking, or having checked, the software is to correct/rewrite faulty code. Once it passes their analysis and is accepted the subsequent revisions would start from there, wouldn't they?
Brian, thank you for your reply. Who can wonder that you look forward to the time that Rick and Jon's reputations are restored to them? For not only would justice have prevailed but you could at last hang up your boots (which would irritate only those thoroughly deserving of such) and enjoy a very well earned rest. I take your point and certainly do not wish to add to your very considerable burdens. My belief is that ZD576 was unairworthy along with its sister HC2's when awarded its restricted RTS by CA. The very high level of engine control and warning malfunctions are far more than initial entering service problems. MOD knew this yet pushed on against BD protests. When the aircraft crashed on the Mull of Kintyre with such a heavy loss of life, and a high profile and highly significant political loss at that, an explanation other than lack of airworthiness had to be found ASAP. The very next day the human error verdict was being bandied about. This hardened in time to the findings that this thread is pledged to overturn. It is my belief that will require the MOD to admit, as they did with Nimrod, that the aircraft was unairworthy.
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Do the loadies still have to do the 15 minute connector checks then?
Regards,
Brian
"Justice has no expiry date" - John Cook
Regards,
Brian
"Justice has no expiry date" - John Cook
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Chinook
Chinook240. It is easy to get lost in this long-running discussion, but perhaps as an operator you could tell us (a) Were the Mk2s airworthy all those years ago? (b) Are they airworthy now? (c) What, if anything, has changed in the meantime? With all good wishes, and, like other contibutors here, sincere appreciation for your operational efforts. JP
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And so are the 'spurious' decu codes, thrown up every 20 mins or so still there? And do the dolls eyes still drop every sortie on the maintenance panel? And do the warninings still come on, on the CAP?
The fact there was a reluctance to bring the a/c back from Boscombe speaks volumes...The test pilot strugled to find a crew to recover an a/c Boscombe wouldnt.
These 'minor' problems were resolved pretty damn quick, certainly within 12 months of the ch47 coming on line across the board post the crash on the Mull.
Indeed, within 12 months the aircraft was being flown by all with full confidence.
Read again the first 3 lines....
The fact there was a reluctance to bring the a/c back from Boscombe speaks volumes...The test pilot strugled to find a crew to recover an a/c Boscombe wouldnt.
These 'minor' problems were resolved pretty damn quick, certainly within 12 months of the ch47 coming on line across the board post the crash on the Mull.
Indeed, within 12 months the aircraft was being flown by all with full confidence.
Read again the first 3 lines....
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Perhaps, encompassing everybody's theory (and being slightly fanciful), the crew had just made the waypoint change when a spurious Eng Fail caption light came on, the crew then made a slight turn to the right to make landfall for an emergency landing and, due to the distraction, hit the Mull. I can't prove that to be correct (and actually doubt it to be correct), but there is no-one who can actually prove it wrong, based upon what little evidence is known. Absolutely no doubt whatsoever? I don't think so.
At the waypoint change the handling pilot applied significant control inputs to turn left up the coast of the Mull causing the connections in the broom cupboard to fail(1) inducing sudden continued changes in fore and aft pitch(2)(3) causing DECU connectors to come partly loose generating multiple spurious warnings(4). The jolting and erroneous warnings overwhelmed the aircrew and uncontrolled the chinook flew on into the fog covered Mull.
Notes:
1. HoL Report Para 57: 57. After the accident the investigators found that both inserts for the thrust balance spring attachment bracket had detached as well as most of the other inserts to both pallets. The AAIB stated, "as an insert could apparently pull out of the pallet without appreciable distress to the components necessarily resulting, the possibility that insert(s) had detached prior to the accident could not be dismissed" (para 7.4.2). In the Flight Control Summary the AAIB reiterated that "the possibility of control system jam could not be positively dismissed" and further stated that "little evidence was available to eliminate the possibility of pre-impact detachment of any of the pallet components" (para 7.4.9).
2. HoL Report Para 115: 115. Witness A also had personal experience of UFCMs in Chinook Mk 1s (QQ 792-6). In one case over a period of days an aircraft bounced vertically every time it was turned right.
3. HoL Report Para 111: 111. In relation to possible jams Squadron Leader Burke explained that, due to the complexity of the Chinook control system, a jam caused by a loose article such as the balance spring in the broom cupboard in one of the three axes, pitch, yaw or roll, could lead to quite random results in all three axes sometimes and certainly in two of them. He had personal experience while lifting off from the ground of a jam in one axis affecting the other two (Q 935).
4. HoL Report Para 54: 54. The AAIB considered the engines and controls and because of the reported FADEC service difficulties investigated the DECUs in detail. DECU no. 2 remained partially functionable with deficiencies consistent with impact damage, and with no faults or exceedances traced in its memory of the last flight. DECU no. 1 had suffered gross fire damage with part of its casing melted away and severe damage to the interior components whereby its memories of exceedance and fault listing had been destroyed.
5. I have not seen the SuperTANs report, but nothing I have read shows that it recorded the attitude of ZD576.
Of course uncommanded pitch changes would mean that there was never any last minute flare.
Equally the lack of a chain of events of co-incident broom cupboard and DECU failures would explain the lack of any further accidents.
Like Brian, I cannot say that this scenario occurred, but to find the pilots guilty of gross negligence then to my mind you have to prove this scenario could not happen.
EG
Last edited by ExGrunt; 23rd Apr 2009 at 15:44.
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Given that the delaminated honey-comb control pallette was re-fixed the day it arrived in Aldergrove, (fact) has anyone asked the question of the qualities of the glue used, the time needed to cure prior to the next flight? And how this is tested? Presumably a ground run with control inputs being made, or an air test? though I am not aware of this happening (fact).
I do know for a fact, as do the other aircrew in NI the day the cab arrived, that the pallette had come away from the floor, as we were all invited to view it. The pallette was raised a good 1 1/2 inches from the floor at the rear, and we all commented on how amazing it was the a/c had still been flyable.
ZD576 was far from being a serviceable a/c when it arrived in NI and whilst Jon and Rick clearly accepted it as serviceable to fly on the sortie that terminated at the Mull, I wonder if it actually was?
I do know for a fact, as do the other aircrew in NI the day the cab arrived, that the pallette had come away from the floor, as we were all invited to view it. The pallette was raised a good 1 1/2 inches from the floor at the rear, and we all commented on how amazing it was the a/c had still been flyable.
ZD576 was far from being a serviceable a/c when it arrived in NI and whilst Jon and Rick clearly accepted it as serviceable to fly on the sortie that terminated at the Mull, I wonder if it actually was?
Last edited by Winch-control; 23rd Apr 2009 at 15:05.