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-   -   Cardiff City Footballer Feared Missing after aircraft disappeared near Channel Island (https://www.pprune.org/accidents-close-calls/617514-cardiff-city-footballer-feared-missing-after-aircraft-disappeared-near-channel-island.html)

Sir Niall Dementia 20th Aug 2019 20:02


Originally Posted by Camargue (Post 10549886)
snd - I do agree with your post and can feel your frustation but the fact remains with the level of CO in Sala's bloodstream both were almost certainly unconcious when the plane hit the water. Had the pilot been a 20,000 hour ATPL the end result would be the same (but we wouldnt know the cause as the plane would have more likely turfed in from fl150 and no bodies would have been found.) This doesnt change the legality of the flight but the cause of the crash was not down to a lack of qualifications.

But, does it make the outbound flight any more legal? Although CO has apparently been found in Sala DI was way outside his qualifications for both outbound and inbound flights. CO poisoning is irrelevant. The flight was illegal and Sala died as a result of a criminal act. From available transcripts, pilot qualifications and aircraft registry the flight was illegal. I’d lay good odds that DI didn’t know the return details until too late. He got airborne knowing a) the flight was illegal, b) he wasn’t qualified to fly that aircraft in those conditions at night. He went, and in doing so killed his passenger. CO poisoning was irrelevant to the legality of the flight and his knowledge of it. CO poisoning may have been an added extra to the already potentially lethal cocktail of bad weather, unqualified pilot and a lot of pressure. CO poisoning is no excuse for his willingness to break the law, it may just have been the final straw.

I’d be interested to know just how CO poisoning could have been detected, at the reported levels in a body that had been under seawater for so many days.

DI had no excuse, CO poisoning is no excuse. And the price was horrendous.

SND

jumpseater 20th Aug 2019 22:01


Originally Posted by Mike Flynn (Post 10550005)
The owner of a maintenance company has also remarked it needed a lot done to bring it up to a safe standard

Whilst there’s plenty of circumstantial evidence that rules were being broken on the accident flight and potentially others, there's no evidence that I’ve seen in the public domain, that indicates that the required maintenance had not been completed at the time of the final flight. If there is perhaps you could provide a link to the source.

megan 21st Aug 2019 00:05

Given the mention of the state of maintenance, was the aircraft even airworthy? Local organisation refused to release an aircraft (100 hourly) when owner pressed not to have certain work done. Owner relented, and paid.

PDR1 21st Aug 2019 06:16


Originally Posted by Sir Niall Dementia (Post 10550112)
I’d be interested to know just how CO poisoning could have been detected, at the reported levels in a body that had been under seawater for so many days.

CO poisoning produces permanent damage to red blood cells - it's a signature which remains and can be identified even in a long-deceased body and it gives fairly precise values of the scale. CO poisoning is not just a matter of lack of oxygen (as happens with CO2) - it is actually a poisonous gas. CO "locks" the haemoglobin in the blood such that it can't take oxygen even when it's present. If you suffer CO poisoning beyond a certain level even getting you away from the CO and giving you 100% oxygen via a mask won't save you - you will die unless you are given a rapid and massive transfusion of red blood cells (which is rarely possible).

So the detection of CO poisoning in "a body that had been under seawater for so many days" is not in any way remarkable or strange.

PDR

The AvgasDinosaur 21st Aug 2019 06:37


Originally Posted by PDR1 (Post 10550358)
CO poisoning produces permanent damage to red blood cells - it's a signature which remains and can be identified even in a long-deceased body and it gives fairly precise values of the scale. CO poisoning is not just a matter of lack of oxygen (as happens with CO2) - it is actually a poisonous gas. CO "locks" the haemoglobin in the blood such that it can't take oxygen even when it's present. If you suffer CO poisoning beyond a certain level even getting you away from the CO and giving you 100% oxygen via a mask won't save you - you will die unless you are given a rapid and massive transfusion of red blood cells (which is rarely possible).

So the detection of CO poisoning in "a body that had been under seawater for so many days" is not in any way remarkable or strange.

PDR

However the time lapse from recovery (of victim) to discovery (of toxicity) does seem both remarkable and strange I.M.H.O.
Be lucky
David

piperp2 21st Aug 2019 07:14


Originally Posted by The AvgasDinosaur (Post 10550377)

However the time lapse from recovery (of victim) to discovery (of toxicity) does seem both remarkable and strange I.M.H.O.
Be lucky
David

I wondered about that one...........

DaveReidUK 21st Aug 2019 07:42

I doubt the delay was to the tests, just to the publication of the AAIB Special Bulletin that contained the results.

jumpseater 21st Aug 2019 08:10


Originally Posted by megan (Post 10550225)
Given the mention of the state of maintenance, was the aircraft even airworthy?.

Is that the bloke who saw the aircraft when it needed maintenance several months before the accident, doesn’t know if any faults were rectified by another agency, and says if they had been rectified, (which he doesn’t know), ‘everything would be fine and dandy’?

The piece regarding your local aircraft is irrelevant.

Sir Niall Dementia 21st Aug 2019 08:11


Originally Posted by PDR1 (Post 10550358)
CO poisoning produces permanent damage to red blood cells - it's a signature which remains and can be identified even in a long-deceased body and it gives fairly precise values of the scale. CO poisoning is not just a matter of lack of oxygen (as happens with CO2) - it is actually a poisonous gas. CO "locks" the haemoglobin in the blood such that it can't take oxygen even when it's present. If you suffer CO poisoning beyond a certain level even getting you away from the CO and giving you 100% oxygen via a mask won't save you - you will die unless you are given a rapid and massive transfusion of red blood cells (which is rarely possible).

So the detection of CO poisoning in "a body that had been under seawater for so many days" is not in any way remarkable or strange.

PDR

Thanks PDR. Some googling on my part comes up with similar explanations. Apparently CO suicides often change their minds, but then find its too late to escape from the stuff.

SND

PDR1 21st Aug 2019 10:40

The most tragic cases of CO poisoniung usually come from campers in the UK. When camping a popular dining solution is to just fire up a disposable barbeque - it's easy, gives a nice charcoaled flavour and involves minimal washing up. But on a typical British camping holiday there is a very high probability that it will be either:

1. Hissing down with rain
2. Blowing a gale
3. Hissing down with horizontal rain

Sadly some decide to use the babeque anyway. To do this they might tip up the sides of their awning/dining-shelter or even just bring the whole thing inside the tent - I've even heard people suggest that this allows the baberque to warm up the tent a bit. The unfortunate fact is that the charcoal burns underneath a layer of ash (the white bit) which resticts the flow of oxygen such that the almost pure carbon produces lots of carbon monoxide (colourless, odourless and deadly). Even in a drafty dining shelter the CO concentration can reach lethal levels very quickly - if the used disposable barbeque is left to burn out inside a tent you will have created a remarkably cost-effective gas chamber for ad hoc executions. So if nothing else, I would ask readers to take away the thought that barbeques are only ever outdoor things - only use in very well ventilated areas no matter hoiw inconvenient that wind may be!

PDR

Mike Flynn 21st Aug 2019 11:25

Carbon monoxide poisoning is an extremely rare cause of aircraft fatalities in the UK.

This aircraft had already flown for over an hour so what could have gone wrong?

PDR1 21st Aug 2019 11:35

Any number of things - the two that immediately leap to mind being either a piece of corrosion in a heat-exchanger finally burning through to give a hole, or simply that the late night return flight was through cooler air so the cabin heather was turned up to a higher level (increating the amount of CO being pushed into the cabin). It's equally possible that the CO leak was present from the moment the engine started, but it too half an hour to build up to a fatal concentration.

The whole "it worked yesteday so it is strange that it broke today" argumnent that we hear so often is utterly inappropriate for complex systems - it assumes dice have a memory, which they don't (I checked).

PDR

G0ULI 21st Aug 2019 13:53

Given that the pilot responded to ATC calls immediately prior to the crash, the claimed potentially fatal levels of carbon monoxide found in the blood may not be quite what they appear from a simple reading of the analytical report. The pilot being considerably less fit and much older than the passenger should have succumbed much more readily to the effects of carbon monoxide poisoning. Biological processes are capable of producing high levels of alcohol and other substances in the blood after death.

There can be absolutely no doubt that carbon monoxide poisoning may have been a contributory factor in this incident, but the primary factors are still weather, an unqualified pilot, and an aged aircraft that had apparently not been maintained to the highest standards. Everything was being done on the cheap in order to save money. There's your cause!

Genghis the Engineer 21st Aug 2019 15:06

There is evidence that sedentary smokers are less prone to hypoxia than fit non smokers.

I have no idea if that maps to CO poisoning, but I suppose it's at least hypothetically possible.

G

Chronus 21st Aug 2019 18:14


Originally Posted by Mike Flynn (Post 10550606)
Carbon monoxide poisoning is an extremely rare cause of aircraft fatalities in the UK.

This aircraft had already flown for over an hour so what could have gone wrong?

Icing, alt air selection, dam burst, all with a maybe of course. As is all too well known, it is rarely one single factor, it is when more than one that conspire to combine to form the chain for an accident.

The interesting one in this incident is yet again the one that relates to human factors. By that is meant what was it that placed this particular pilot and his passenger in that aircraft for that fateful flight.

Laguna123 21st Aug 2019 18:39

M.O.T
 

Originally Posted by megan (Post 10550225)
Given the mention of the state of maintenance, was the aircraft even airworthy? Local organisation refused to release an aircraft (100 hourly) when owner pressed not to have certain work done. Owner relented, and paid.

My first post as I have had an interest in this from the start and sat and watched what people have been saying.

Maintenance has started to become an issue for obvious reasons.

My understanding is that from what Mr Penney has stated is that the aircraft was due an MOT at the end of the year, so a good guess is December.

So other flights in the said aircraft could have taken place before the fatal night.
i suppose my thoughts are: could this of have been an in flight issue not caused by bad maintenance if the aircraft had clocked up a fair few miles since its MOT. This can certainly happen in a Car even after a few weeks of it passing its Test. failure of parts

double_barrel 22nd Aug 2019 05:33


Originally Posted by PDR1 (Post 10550358)
CO poisoning produces permanent damage to red blood cells - it's a signature which remains and can be identified even in a long-deceased body and it gives fairly precise values of the scale. CO poisoning is not just a matter of lack of oxygen (as happens with CO2) - it is actually a poisonous gas. CO "locks" the haemoglobin in the blood such that it can't take oxygen even when it's present. If you suffer CO poisoning beyond a certain level even getting you away from the CO and giving you 100% oxygen via a mask won't save you - you will die unless you are given a rapid and massive transfusion of red blood cells (which is rarely possible).

So the detection of CO poisoning in "a body that had been under seawater for so many days" is not in any way remarkable or strange.

PDR

Cold you point me to some background on that? My understanding is that, as you say, CO binds very tightly to Hb blocking O2 attachment, but I wasn't aware of any detectable damage to the rbc's themselves. And even if that was the case, I would expect virtually every rbc to be lysed so long post mortem. I had assumed that CO would eventually dissociate from Hb after death because of all the changes that must completely screw-up the Hb molecule. i guess maybe some blood deep in the tissues would be preserved well enough for an analysis?

ShyTorque 22nd Aug 2019 05:59


Originally Posted by Laguna123 (Post 10550963)

My first post as I have had an interest in this from the start and sat and watched what people have been saying.

Maintenance has started to become an issue for obvious reasons.

My understanding is that from what Mr Penney has stated is that the aircraft was due an MOT at the end of the year, so a good guess is December.

So other flights in the said aircraft could have taken place before the fatal night.
i suppose my thoughts are: could this of have been an in flight issue not caused by bad maintenance if the aircraft had clocked up a fair few miles since its MOT. This can certainly happen in a Car even after a few weeks of it passing its Test. failure of parts

Laguna, that is why an aircraft used for public transport is required to be on a regular inspection and maintenance programme, controlled by the authorities. With an aircraft you don't just wait until the "MOT" to see if anything needs doing. An aircraft used on a merely private basis isn't required to be maintained quite so strictly.
Obviously, regular maintenance on an aircraft costs a lot of money.

This is one of the reasons why real professional operators get very upset by amateurs undercutting them on price and therefore on safety. See the posts placed here by SND, for example.

PDR1 22nd Aug 2019 11:09


Originally Posted by double_barrel (Post 10551280)
Cold you point me to some background on that? My understanding is that, as you say, CO binds very tightly to Hb blocking O2 attachment, but I wasn't aware of any detectable damage to the rbc's themselves. And even if that was the case, I would expect virtually every rbc to be lysed so long post mortem. I had assumed that CO would eventually dissociate from Hb after death because of all the changes that must completely screw-up the Hb molecule. i guess maybe some blood deep in the tissues would be preserved well enough for an analysis?

I was probably a little careless in my choice or words - in this instance by "damaged" I meant that the Hb is permanently put in a state where it cannot transport oxygen - once it has formed CO-Hb i6t is essentially impossible to get it to release the CO and form the O2-Hb which can accept and release oxygen in the "usual" manner, so (in my usage) the Hb is "damaged". There are various ways of determining the propotion of CO-Hb in a blood sample (and indeed in other body fluids) from gas chromatography at the expensive/accurate end to manual spectrometry at the "cheap, time-consuming and reliant on skill" end. But most path labs use an autmated spectrophotometry technique, usually in the form of a specifically designed "CO-oximetry analyser". These machines have proven to be pretty reliable and sufficiently accurate to give a confident post-mortem indication of whether CO-Hb was a cause (or significant contributor) of death.

CO-Hb itself seems to be a remarkably robust and stable molecule which doesn't decay much in normal conditions, and barely decays at all when chilled, so a few days on the sea bed is unlikely to compromise the results significantly. There was a reason why I was aware of all this which I'm afraid I can't go into, but the subject of post-mortem determination of C) poisoning is a well published field because (I understand) CO-poisoning is the most common form of lethal poisoning in the western world. Most of the papers get very technical very quickly, but an easily digestable source would be this one:

https://acutecaretesting.org/en/arti...em-co-oximetry

You may be espcially interested in the section headed "STABILITY OF COHb WHEN MEASURED BY CO-OXIMETRY" (about 2/3ds of the way down) which provides the following:

"A number of studies [23, 27, 28] have addressed the issue of stability of COHb as measured by CO-oximetry in stored blood samples. They have confirmed that COHb is remarkably stable.

No change in CO-oximetrically determined COHb from baseline was noted in postmortem samples collected into heparin and stored for up to 3 years in a refrigerator [28].

Hampson [27] determined that there was no significant change from baseline in COHb for unrefrigerated samples mailed across the US and back again. And Kunsman et al[23] confirmed that stability of CO-oximetrically determined COHb was not dependant on the use of a particular anticoagulant/preservative combination."


HTH,

PDR



double_barrel 22nd Aug 2019 12:06


Originally Posted by PDR1 (Post 10551582)

HTH,

PDR

Thanks, that's very helpful. And as you say, it goes a long way to explain the lethality of CO, I knew its binding to Hb was tenacious, but had no idea it was locked-in like that. I think I will take a look at the underlying biochemistry out of interest.


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