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Who were the "police observers" and how did they get there?
100% not pilot Suicide.
How can you come to a conclusion that it was not murder-suicide with any more certainty than it was murder-suicide?
konabunny - MemberHow can you come to a conclusion that it was not murder-suicide with any more certainty than it was murder-suicide?
Take a step back... If you plan to crash a helicopter into, for some reason, a pub, why would you take steps first to make it harder to fly? The sequence of events makes this scenario seem incredibly unlikely, I like a bit of tasteless speculation about tragic events as much as the next man but I think you have to really [i]want [/i]to believe this.
And
konabunny - MemberWho were the "police observers" and how did they get there?
They were Police observers- that's what Police helicopters are for, observing. They got in through the door.
Is there a reason to switch off the transfer pumps at the first warning? Wonder if you're not supposed to run the pump dry so he turned it off and tried to continue on the other tanks...
I remember from reading the Apache and Hellfire books that Army Air Corps pilots can get in bother if the return with tanks below a certain level....wonder if the pilot here had a vested interest in keeping as much fuel as possible in the main tank?
EDIT - Actually, no point in a layman regurgitating content from the report when there are people who know their stuff.
Reading though this, and as a complete layman, I'm also minded of other crashes where the pilot has misunderstood what's going on. Is it possible he heard the warnings, looked at the main fuel gauges and saw he had plenty of fuel left, and assumed that there was a fault with the warning system?
Doesn't explain why the pumps were off, but might explain why he kept flying after the warnings sounded.
Short Answer: Pilot Error.
Long answer: unknown.
Ie, we know the pilot failed to carry out the correct low fuel procedures, failed to land in direct contravention of the operating requirements, and then failed to carry out an emergency autorotation.
All those things we know.
What we don't know, and almost certainly never will, is the chain of events that lead to those actions (or lack or actions) occurring.
It's like to be a highly complex situation, almost certainly with affects of tiredness, confusion, and also other behavioral aspects (such as not wanting to land and then have to be recovered etc).
flight data/cockpit voice recording are taken on board as this may well have answered a lot of people's questions a lot sooner.
Err. How would that help. The FDR would tell you that the pumps were switched off, but not why. The CVR is hardly going to record him saying. "I'm just going to switch the pumps off because of x" unless he was in the habit of talking to himself
I'm apalled at some of the stupidity displayed on here today. (The suicide speculation) Sorry guys. Has to be said.
I would say it was more likely the pilot knew he was low on fuel so was limiting the amount transferred into the fuel cells to better help him manage the fuel. He may have then left it too late to re-engage the transfer pumps meaning they didn't kick in and caused the aircraft to go down.
Auto rotation at night in a busy built up area would be horrendous. If he was low flying anyway the chance for him to utilise autorotation would be low.
I'm no pilot though!
[quote=somouk ]I would say it was more likely the pilot knew he was low on fuel so was limiting the amount transferred into the fuel cells to better help him manage the fuel.
I still don't see any way in which that would help.
Just to back up the pilot error bit, these things do happen and I can see how they could happen more easily in a situation where there's only one pilot.
The transcript from the CVR of Air France 447 is a good example of this and makes for some sobering reading: [url= http://www.popularmechanics.com/flight/a3115/what-really-happened-aboard-air-france-447-6611877/ ]http://www.popularmechanics.com/flight/a3115/what-really-happened-aboard-air-france-447-6611877/[/url]
From my completely uninformed viewpoint it's got pilot error written all over it, I don't know where the suicide theory comes from. The sad thing is all the reports of anger from surviving relatives about unanswered questions, the AAIB report is as utterly thorough as any such thing can be given the circumstances. We don't know why the transfer pumps were turned off, but mistakes do happen - Eastern Airlines 401, British Midland 92, Air France 447, etc.
Meant to say thanks for the insights from all, Moose in particular.
The 'returning to base' doesn't add up. I could have sworn there were eye witnesses who say the helicopter was hovering over the pub when it fell, the crash photos would also suggest this. There appears to be no forward momentum in the helicopter when it crashed.
I thought that was covered, an attempted flare at too high an altitude killed forward motion so the final impact was an almost vertical descent? Will see if that's justified or just inebriated ramblings.
Ok, at least a smidge of rambling -
"The Emergency and Malfunction Procedures advise pilots to flare at a height
of 100 ft agl and establish the landing attitude for the touchdown, maintaining heading and applying the collective lever to reduce the rate of descent and cushion the touchdown.
The evidence at the accident site indicated that the helicopter had no forward
speed at impact, which implied that a flare manoeuvre had been carried out
during the final descent. Flaring the helicopter also had the potential to increase
the Nr, if the speed of the rotors was above 75%. However, the height at which
the flare manoeuvre was carried out could not be determined."
Fair enough, but when the warnings sound, would checking the transfer pump switches not be one of the first things you do? He had a good 10 minutes to do that.
Suppose at that point you realised that you'd inadvertently turned the transfer pumps off a few minutes earlier, but instead of switching the transfer pumps back on, you mistakenly turned the primer pumps on (the report notes that these were adjacent, and were inexplicably in the on position after the accident).
You might then feel completely confident that you'd understood the problem and fixed it, and then ignore the continuing warnings because it would take some time for the transfer pumps to replenish the supply tanks.
Pure speculation, but as others have said, this sort of misunderstanding of the situation seems the most likely explanation. The fact that they continued with normal operations after the warning suggests that the crew weren't concerned by what should have been a serious warning.
As for why the transfer pumps got turned off in the first place - the report speculates that one of the pumps may have run dry, resulting in a warning, the correct resolution of which was to turn one (but not both) transfer pump off. Perhaps this was fumbled.
As an experienced aviator but with only a couple of hours on Helos, I would imagine it was quite stressful when he got those low fuel cautions at night, over a city with potentially limited landing options.
The 'press-on-itis' to recover to base might have been overpowering when he thought he had 10 minutes of fuel and the immediate options to land might have been hazardous. I've known very experienced pilots get themselves caught out fuel-wise due to various factors. There might have been other self-generated pressures to continue to base, who knows?
Switches can be left in the wrong place; I'm lucky, in my jet I have another pilot to point out I've done something wrong, one of them on this thread. He didn't. We all make mistakes. Some are a pride-thing, some are safety critical. It's just trying to trap and mitigate them at the right time.
What other rotary types had he flown? Were the switches differently orientated? Difficult to see at night?
This really doesn't even sniff of foul play and any suggestion of that is unfounded and in poor taste.
It sadly appears to be a catalogue of errors (we'll never know the causes of them all) that lead to the fateful flameout.
Pretty much like any aviation incident. Just with an awful outcome. RIP.
Sorry for my ignorance, but what is autorotation?
Is it normal to fly helicopters with such low fuel reserves, do they not have rules like airlines?
I think it's when they free fall enough to get the rotor spinning again (like a sycamore seed), so they can then go forward a bit. I think.
Sounds like there was plenty of fuel but it wasn't going where it should have because the switches were wrong.
[url= http://fearoflanding.com/accidents/accident-reports/glasgow-helicopter-crash-mystery-76kg-of-fuel-in-tank/ ]Good write up of the incident/report on Fear of Landing blog here[/url]
This really doesn't even sniff of foul play and any suggestion of that is unfounded and in poor taste.It sadly appears to be a catalogue of errors (we'll never know the causes of them all) that lead to the fateful flameout.
Pretty much like any aviation incident. Just with an awful outcome. RIP.
This is the best somethingion in this entire thread. Too many amateur sleuths, too may looking for blame. Sadly there doesn't appear to be such a thing as an accident now.
This is an interesting thread. The contributions from people in the know are very interesting.
Basically it confirms that well trained people will some times do the wrong thing under pressure. Sat at the key board it seem obvious that if an alarm sound warning you of blank then you would swiftly rectify the situation, But that Air France 447 crash shows that people get it wrong. They think they think they know what wrong and have done the right thing to correct it.
This article is worth a read even though its from the Daily Mail. Its the story of a woman dieing on an operating table. The amazing thing at least 3 people present had the skills to save her and the equipment needed was in the room. People get things wrong
It appears that moments after being sedated, Elaine's airway collapsed, preventing adequate levels of oxygen from reaching her brain. Though potentially an emergency, the event is a recognised risk during an anaesthetic and, as such, should be manageable.
Surgeons and anaesthetists are drilled to follow a series of steps at this point - beginning with a non-invasive attempt to get the patient breathing normally, and ending, as a last resort, with an emergency surgical procedure.
This is usually a tracheotomy - where the surgeon cuts through the windpipe, inserting a tube directly into the airway through the throat.
At first the drill was followed impeccably. But then a problem arose: the surgical team tried to get a tube into the airway to help Elaine breathe, but encountered some kind of blockage. According to the drill, this was the time to consider doing a tracheotomy.
Elaine, by this point, was turning blue in the face and one of the nurses fetched tracheotomy equipment. A second nurse phoned through to the intensive care unit to check there was a spare bed available.
But the three consultants appear to have made the sort of human error that is horribly common in crisis situations. They became fixated on what they were doing. The consultants also appear to have ignored the junior staff and remained intent on finding a way to insert a tube into the airway.
The minutes ticked by. After 25 minutes, they were finally able to get a tube into her airway -but even then, the team failed to secure the tube and it was a full 35 minutes before adequate oxygen levels to the brain were restored.Read more: http://www.****/health/article-421989/Blunder-killed-wife.html#ixzz3pW9bLCmY
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Sorry for my ignorance, but what is autorotation?
I'm not a pilot but
Let the helicopter fall building up kinetic energy in the rotor, this slows the descent some what as well
Near the ground reverse the pitch of the rotors to convert the rotors kinetic energy to thurst and slow you still further
Regarding the speculation about the pilot trying to land outside the pub on the junction, the helo flew downstream (river clyde) past glasgow green. Huge big open space with next to no folk pottering about.
If he wanted to land somewhere, that would in my view would appear to have been prime...
Subsequent to the flameout? I doubt that.
It is yards.....
@allfankledup: Do you have any idea what that would look like from the air at night? Black nothingness, that's what. Personally I'd rather shoot an approach to ground I can actually see.
Allfankledup
how many hours do you have on type? Have you flown this route at night in the given conditions in recent times? Are you fully appraised of the pilot's workload/arousal/stress in this case?
The AAIB who comprise of test pilots, line pilots, engineers and psychologists all haven't explained the decision making and mechanical inputs of the handling pilot, so I'm not sure your comments have any value, unless you know a whole lot more you're not saying.
Glasgow Green has trees, lamp posts, an obelisk, loads of other junk it would be very bad news to land on - I might well go for the lit up junction I could at least see rather than take a chance on landing into blackness.
[quote=somafunk ]Good write up of the incident/report on Fear of Landing blog here
Thanks for that, it answers most of my questions. Definitely looking more AF447 - the pilot somehow made several mistakes and they compounded. I presume there are changes which could be made to prevent such mistakes being made, or prevent them causing a crash, but this is such an unusual occurrence that the issue hadn't arisen before?
I'll happily apologise for my stupid comments earlier in this thread.
As the main tank still contained fuel, and the two supply tanks were running towards empty. If the main tank pump were operated, would it be able to supply fuel at a rate sufficient to keep the engines running?
Yes. According to the report, either one of the pumps can deliver more fuel than both engines on full power, and in normal operation fuel constantly spills back from the topped-up supply tanks back into the main tank.
I presume there are changes which could be made to prevent such mistakes being made, or prevent them causing a crash, but this is such an unusual occurrence that the issue hadn't arisen before?
The report is very thorough, and lists every known case where the transfer pumps were erroneously turned off, but concludes that in all cases the circumstances were different to this one.
The specific recommendations made by the report are limited to recommending the installation of flight recorders, and to ensuring that the radio altimeter continues to work after loss of both engines, which might have improved the chances of a successful autorotation as there's evidence to suggest that the pilot flared the autorotation too high above the ground.
Newer helicopters have pumps that can be run dry without harm. This removes the one legitimate cause for switching off a fuel transfer pump in flight, although the report seems skeptical about dry running being the reason for the pumps being switched off during the flight.
Auto-rotation, with the engines off you need to immediately lower the collective to maintain rotor speed. Once the rotor speed has decayed below a certain percentage of normal rpm then you are not getting it back and they will stop turning very quickly. That percentage might be 80-90% depending on type of helicopter so there is little margin for error.
AS the helicopter approaches the ground you raise the collective to flare for the landing. In all of this though you need forward airspeed, it won't be able to hover.
It sounds like on this occasion the pilot misjudged his flare hight and ended up at 100 feet with no forward speed and the rotors stopped.
imnotverygood - MemberErr. How would that help. The FDR would tell you that the pumps were switched off, but not why. The CVR is hardly going to record him saying. "I'm just going to switch the pumps off because of x" unless he was in the habit of talking to himself
Correct FDR will provide pump status....if it's one of the parameters recorded. CVR on the other hand would hopefully provide an insight into what was going on during the flight. It picks up not just speech of the pilot but all those onboard as well as ambient noises (engine/transmission sounds for example). I would expect one of the observers to be sat in the front assisting the pilot at times with checklists etc and I would expect that there would be conversation going on all the time rather than flying in deathly silence. Good crew resource management would dictate that the pilot would have appraised the crew of the low fuel warnings and communicated his intentions based on what he thought the situation was; just because the observers are not aircrew does not mean the pilot does not talk to them and tell them what is happening.
There is no guarantee that had there been a CVR fitted it would answer all the questions that remain, however it may have provided a much needed insight into the reasons for certain decisions.
Question for the experts... under what circumstances are the transfer pump switches required?
My car has a fuel pump (+ regulator and return), it's essential at all times for the car to run, as I imagine they are in a helicopter, or not....?
When would you switch them off normally, or in an emergency situation?
Is it just for when a pump is faulty? any other reasons?
An aircraft has multiple fuel cells, the transfer pumps transfer fuel between these cells. There's a few different configurations but that's all technical wobble.
And depending on the configuration when/what/how/why/etc will dictate when the transfer pumps are turned on, or off. But that will all be laid down in the tech manuals and flight reference cards.
[quote=pdw ]Newer helicopters have pumps that can be run dry without harm. This removes the one legitimate cause for switching off a fuel transfer pump in flight, although the report seems skeptical about dry running being the reason for the pumps being switched off during the flight.
I've seen comments in other reports about the pumps being switched off because they're running dry - presumably when fuel in main tank gets low and when flight manoeuvres result in fuel not sitting level in the tank - because running dry damages the pumps. Though as pdw says, the report seems to dismiss the idea that the pumps would have run dry.
When would you switch them off normally, or in an emergency situation?
Only if one of the pumps runs dry. As the main fuel tank becomes low, either the front or rear pump may become uncovered, depending on the pitch of the helicopter. In this case, you turn the affected pump off to stop it overheating, but you wouldn't turn both off.
The report deemed that it was feasible that one of the two pumps would have run dry based on the fuel level and maneuvers being flown, but that a) the warning would have happened a few minutes after they calculated that the pumps were turned off and b) should have resulted in only one pump being turned off.
My car has a fuel pump (+ regulator and return), it's essential at all times for the car to run, as I imagine they are in a helicopter, or not....?
If you're interested, it's worth reading the full AAIB report. It gives really quite a good explanation of how the system works.