Ed Helicopter Crashes into Glasgow Pub

[Nessie]

On the other hand, when you look up in that situation, you're looking up at sodium street lights. These interfere with night vision, and dazzle. I'm not convinced he was really able to see something coming down from above street-light level.

Rolfe.

The sodium lights are yellow so as not to dazzle. The main thing they interfere with is colour recognition. A helicopter with is flight lights on would be visible looking up from the street. If anything the speed of it falling may mean people hear but do not see it.

 

[Information Analyst]

Strathclyde police have an unfortunate record with helicopters.

I think this is their third accident. I don't know how typical that is for police use of helicopters. They do tend to spend a lot of time hovering over built-up areas- and counter intuitively, hovering is not what helicopters are designed for.

I'm pretty certain the Metropolitan Police use the same type, and obviously spend a lot of time hovering over urban areas, but I'm not aware of any crashes in the 12 years I've lived in London. It's unfortunate that some new reports are being couched in terms of how widely used the Eurocopter is, "but now there are concerns about its safety."

Whatever happened here sounds like major failure. The descriptions of it falling out of the sky sound like autorotation was not even possible. Sounds like the whole rotor linkage just ...stopped. Total gearbox crack-up maybe?

After the multiple north sea Super Puma failures and now this, I wonder if we will see tightened regulation of chopper flight over built up areas?

I doubt that's going to happen for police helicopters, despite this. The failure rate in the offshore industry is, I suspect, an inevitable result of how over-use the aircraft are.

 

[Rolfe]

Seeing the chopper over the crowd in September, it would never have occurred to me to worry that it might crash on us. But then someone turned round and expressed exactly that concern, on the basis of the number of crashes that had occurred.

Rolfe.

 

[LondonJohn]

Total number does nothing to back up your statement- "Still much safer than many other forms of transport. "


Look up some comparison, like fatalities/passenger mile. I bet you'll find that putting you foot aboard a helicopter is like stepping into a grave with the other foot on a banana peel.

Fixed wing pilots call helicopters "10,000 parts all flying in close formation" for a reason. They are just waiting to break formation.

I used to have a PPL, and I wouldn't go in a helicopter if I could reasonably avoid it (I've had four helicopter flights - two military and two commercial - and I don't plan to have many more).

My father was a military fighter pilot and he wouldn't go anywhere near a helicopter.

There's a very good set of reasons why fixed-wing pilots are reticent about helicopters in comparison to fixed-wing:

1) Helicopters are inherently aerodynamically unstable: there is virtually no aerodynamic lift generated in forward (or stationary) flight other than that developed by the powered rotation of the main blade. If the main blade fails, you're in big trouble.

2) There's zero redundancy. If anything in the main rotor mechanism - whether powerplant, gearbox, drive or rotor set - fails, then the whole machine fails. By contrast, almost all aircraft are capable of safe flight with single engine failure.

3) There's an added potentially-catastrophic failure point for nearly all helicopters, and that's failure of the tail rotor. Even if the main rotor is fine, a tail rotor failure will almost-inevitably cause uncontrollable counter-rotation, and an uncontrolled descent. Therefore, it can be said that a failure of either of the rotor sets of a helicopter could well cause a catastrophic loss of stable flight. Those aren't great odds......

4) The angle of attack of helicopters in failure tends to be very steep and high-velocity, whereas fixed-wing aircraft - even in total mechanical failure - are usually controllable to the extent of being able to make a shallow descent (unless of course there's either total electrical/hydraulic failure and/or significant structural damage, but those are rare compared with power-delivery-related failure.

5) The key power element of a helicopter - the main rotor drive - is a set of components operating under severe torsion loads. Metal fatigue under long-term load profiles is a real possibility - if servicing practices aren't scrupulously observed, you can end up with fatigue failures in critical components, particularly in the gearbox, final drive and rotor assembly.


Having said all that, I know a couple of helicopter pilots, and they both have utmost faith in their mode of flight (and the machines they use). And of course the Glasgow crash is a double tragedy because of the apparent loss of not only the crew but also the people on the ground. I hope that the AAIB and other authorities can get to the bottom of it, so that at least we can try to minimise the chances of something similar happening again.

 

[LondonJohn]

Seeing the chopper over the crowd in September, it would never have occurred to me to worry that it might crash on us. But then someone turned round and expressed exactly that concern, on the basis of the number of crashes that had occurred.

Rolfe.

Well of course in absolute terms, the odds of a helicopter crashing during any one given flight are probably in the order of 1:100,000 or more*. So from a purely statistical analysis, the vast majority of people who fly in helicopters - including those who fly helicopters for a living - are never going to experience a serious failure or uncontrolled descent.

But Poisson distribution being what it is (it deals with the probability distribution of rare events), I'm still not that keen on the odds.

* Probably a lot more - I haven't checked.

 

[LondonJohn]

I'm pretty certain the Metropolitan Police use the same type, and obviously spend a lot of time hovering over urban areas, but I'm not aware of any crashes in the 12 years I've lived in London. It's unfortunate that some new reports are being couched in terms of how widely used the Eurocopter is, "but now there are concerns about its safety."

The Met actually uses EC-145 helicopters - they are a slightly bigger model than the one that crashed in Glasgow, but with similar spec.

I doubt that's going to happen for police helicopters, despite this. The failure rate in the offshore industry is, I suspect, an inevitable result of how over-use the aircraft are.

And to an extent it's nothing more than a function of the sheer number of journeys made by these helicopters per annum (i.e. without any suggestion of "over-use" with its attendant connotations of poor servicing, pilot fatigue, etc). In addition, many of these journeys are made in appallingly bad weather, and of course they're almost exclusively over open, hostile seas. Therefore, any forced landing is more likely to be a) serious, b) newsworthy and c) fatal - compared to a similar level of forced landing over land.

 

[LondonJohn]

A legal journalist who should know better is collecting "eyewitness" accounts from the PA103 crash, which happened at 19.08 on the winter solstice, and using them to shore up a fantastical conspiracy theory.

I have remonstrated with him that no matter what someone thought they saw at that time, even if it was published in newspapers which were printed well before sunrise the following morning, if what was revealed by that sunrise was categorically something different, these people must be mistaken. No joy.

I imagine the AAIB will treat the Sun editor's evidence with due caution.

Rolfe.

My father served on three different RAF Boards of Inquiry into fatal accidents. In two of them, the Board found that nearly all the eyewitness testimony was fundamentally (and provably) flawed. In one of them, several people reported seeing exactly the same (incorrect) manoeuvre preformed by the aircraft prior to impact; two ten-year-old German schoolgirls were the only ones who accurately described what had happened.

 

[Duffy Moon]

It seems that Stranraer FC's captain is a firefighter in real life.
He worked through the night at the crash site, then turned out for his team.

http://www.bbc.co.uk/sport/0/football/25172701

 

[Rolfe]

My father served on three different RAF Boards of Inquiry into fatal accidents. In two of them, the Board found that nearly all the eyewitness testimony was fundamentally (and provably) flawed. In one of them, several people reported seeing exactly the same (incorrect) manoeuvre preformed by the aircraft prior to impact; two ten-year-old German schoolgirls were the only ones who accurately described what had happened.

It's not impossible Smart was right, but there was a guy on the news specifically warning against putting too much faith on an eyewitness report of something that happened pretty fast, was shocking, and was not something the person was accustomed to seeing.

I'm not surprised children were the most accurate - they can be very literal observers without pasting their own preconceptions on what they're seeing.

In the Lockerbie crash, one observer reported seeing the intact plane cross the A74 road from west to east at a height of no more than 500 feet. That's impossible, as the plane was going in the opposite direction, and didn't make it past the road. It is also absolutely clear that it broke up at 31,000 feet, from the radar returns and from the very wide distribution of the debris. The observer probably caught a glimpse of the wing assembly just before it hit the houses.

Other reports said the plane crossed directly over the town of Langholm, due east of Lockerbie, and hit a hilltop and bounced off on the way to Lockerbie. That's also impossible, as the flight path wasn't at the right angle for that, and there was no hill that had been hit by the plane.

Mistaking what happened in the dark when something shocking happens very suddenly is easy enough to do. The trouble starts when people won't admit they were mistaken and persist with their version. Then when the authorities get fed up with it they start bleating about a cover-up. Then conspiracy theorists latch on to them, and you have a full-blown CT.

Let's hope it doesn't happen with this incident.

Rolfe.

 

[Darth Rotor]

I flew in both fixed wing and helicopter in the Navy. Did some instructing in both.

Helicopters take more maintenance, and they certainly have their maintenance challenges. The North Sea and Gulf of Mexico oil fields rely on rotary wing transport for their manning of the rigs. Most of the time, it all works out ... because of how far the industry has advanced in the past forty years. The down side of commercial operations is the bottom line attitudes that can lead to cutting on maintenance ... and other things that as a pilot chill my blood. (See the S-92 that crashed a few years ago in Canada, most on board died, for one example ... has to do with the bolts holding on the oil filter ... )

There are two of you whose opinion of helicopters are based in emotion: fear.

Are you going to take counsel of your fears? If so, suggest you review whether or not you choose to operate a motor vehicle.

 

[LondonJohn]

I flew in both fixed wing and helicopter in the Navy. Did some instructing in both.

Helicopters take more maintenance, and they certainly have their maintenance challenges. The North Sea and Gulf of Mexico oil fields rely on rotary wing transport for their manning of the rigs. Most of the time, it all works out ... because of how far the industry has advanced in the past forty years. The down side of commercial operations is the bottom line attitudes that can lead to cutting on maintenance ... and other things that as a pilot chill my blood. (See the S-92 that crashed a few years ago in Canada, most on board died, for one example ... has to do with the bolts holding on the oil filter ... )

There are two of you whose opinion of helicopters are based in emotion: fear.

Are you going to take counsel of your fears? If so, suggest you review whether or not you choose to operate a motor vehicle.

I'm guessing that one of the "two" you're referencing above is me......

But you may have misinterpreted my post(s). What I actually said was that I prefer not to use helicopters if I can reasonably avoid doing so. What I actually said was that there are good, engineering-based reasons why helicopters are inherently more risky than fixed-wing aircraft. What I actually said was that the catastrophic failure rate in helicopters is still very very low in absolute terms (I used 1 in 100,000, and added that this was still probably a significant overestimation), but that the nature of Poisson distribution would still make me wary of using a helicopter if a reasonable alternative were available.

By the way, your point about using a motor vehicle is a hackneyed canard that is a favourite among aircraft operators of all types: "You're more likely to die on your car journey to the airport than you are during the subsequent flight". The only problem is that it's not really true. If you have the stomach and the patience for a detailed statistical analysis of this area, you might read this:

http://www.rvs.uni-bielefeld.de/publications/Reports/probability.html


Regarding the relative safety rate of helicopters vs fixed-wing, it's intrinsically difficult to make a valid comparison, mainly owing to the different ways (and roles) in which those two types of aircraft are typically employed. But pretty much every study that's attempted to do some sort of meaningful comparison has concluded that helicopters are significantly more risky than fixed-wing (with the underlying caveat that both are low-risk in absolute terms). Here, for example, is a study suggesting that offshore helicopter transportation is 10 times more dangerous than equivalent fixed-wing journeys:

http://www.si971.com/helicopter_fatalities_10-ti.html


In summary, I certainly don't have any sort of irrational fear of flying in helicopters. And I never said I did. What I said was that I prefer not to do so if I can avoid it, for reasons grounded in engineering principles and statistical analysis.

 

[Soapy Sam]

I always rather liked helicopters. As a kid, I loved watching "The Whirlybirds" (Anyone else remember that?). Flying overland is great because I love to see the scenery. The Shetland coast is pretty spectacular.
I've had some bad chopper trips out west of Shetland,- fog / cloud all the way, winds and turbulence, but even then I prefer them to fixed wing. Lots of psychological factors there. I really don't like flying in jets and I've done so monthly at least for 35 years. I hope to stop soon.
TV news this morning shows no change in the Glasgow situation. No new deaths, no major progress recovering the wreckage. If they ever found that man's missing father, I have not heard it mentioned. I hope he's off on a blinder somewhere, but it doesn't sound likely.

 

[Soapy Sam]

The sodium lights are yellow so as not to dazzle. The main thing they interfere with is colour recognition. A helicopter with is flight lights on would be visible looking up from the street. If anything the speed of it falling may mean people hear but do not see it.

The lights are yellow , cos they're sodium. Not a lot of choice in that department. Slowly being phased out, I think.

 

[Rolfe]

They've still only named one victim, which suggests the rest of the bodies have not yet been recovered. The man named was one of the audience in the pub. That poor man who has been waiting outside since Friday night saying he knows his father was in there still hasn't had any definite news, apparently.

The blood transfusion service have been tweeting to keep people away. They said they had enough blood, and had to concentrate on getting it to where it was needed. They were telling would-be donors they didn't want them yesterday, they want them in later December and into January to replenish stocks and keep them healthy. Lots of public education about donating regularly so that stocks are already in place to cope with this sort of incident, which thankfully was the case this time.

More speculation that the chopper could have made Glasgow Green (maybe 200 yards away), or even the river (just across the road, not good for the occupants of the helicopter but good for people on the ground) if the pilot had had any control at all. Even a crash on the road would have been less catastrophic by quite a long way. Something very very drastic has happened to that thing.

Rolfe.

 

[Craig B]

More speculation that the chopper could have made Glasgow Green (maybe 200 yards away), or even the river (just across the road, not good for the occupants of the helicopter but good for people on the ground) if the pilot had had any control at all. Even a crash on the road would have been less catastrophic by quite a long way. Something very very drastic has happened to that thing.
Rolfe.

Yes I raised that at #28. It means the pilot can't have been trying to use the flat pub roof as an emergency landing pad, surely; also that the gliding effect from the spinning rotors couldn't have operated. It makes helicopters seem rather insecure, as some posters have suggested.

A question, for most police purposes, would it be possible to use fixed wing aircraft? I think one was designed to replace police helicopters recently, but wasn't a success, if I remember right. Anything that might prevent a repetition of this disaster.

 

[Skwinty]

If the helicopter was in any part of the shaded areas of the attached height/velocity diagram, then engine failure would mean a very low probability of successful auto-rotation resulting in an uncontrolled descent.

May the deceased RIP.

 

[Soapy Sam]

Yes I raised that at #28. It means the pilot can't have been trying to use the flat pub roof as an emergency landing pad, surely; also that the gliding effect from the spinning rotors couldn't have operated. It makes helicopters seem rather insecure, as some posters have suggested.

A question, for most police purposes, would it be possible to use fixed wing aircraft? I think one was designed to replace police helicopters recently, but wasn't a success, if I remember right. Anything that might prevent a repetition of this disaster.

Blimps or small drones may be the way forward. Perhaps even microlights.
There has been talk about using the sort of drones used for ground attacks in Afghanistan. Not wildly popular with Joe Public.
For surveillance, a more advanced version of the quad copter Rolfe described in another thread is one possibility. These are fine for surveillance and intelligence gathering, but can't actually arrest someone.

The question about using vehicles to chase suspected villains on the ground is a complex one. There have been a number of high profile deaths and injuries of bystanders by police vehicles on the ground. If a thief, fleeing in a stolen car is dangerous, is it any safer to have him chased by police in another car? Or is that twice as dangerous?

A small, radio operated quadcopter that could track a car might be a far safer (and less expensive) option for much of what police helicopters do.

 

[mummymonkey]

Inside of bar. The aircraft impact is said to be more or less where the couple are sitting on the left. The band were playing on the right. Imagine this with over 100 people inside.

Source: http://ahaufstop.blogspot.co.uk/2011_03_01_archive.html

 

[Craig B]

My daughter reminded me of an incident involving the Clutha last year. She was there early one evening with a friend, a woman from London. They left to go shopping but the friend forgot to pick up her purse, and left it on the table. Another customer spotted it, handed it to one of the bar staff who recalled who left it, and proceeded to run more than 200 yards along the road to find her and return it.

The English lady was astonished that such concern had been shown to a complete stranger in a city centre bar, and said it wouldn't have happened like that in London. I don't know if that's true, but my daughter extends her gratitude to the employees of the Clutha and hopes they are safe and sound.

 

[commandlinegamer]

Source: http://ahaufstop.blogspot.co.uk/2011_03_01_archive.html

Nice find.