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-   -   Police helicopter crashes onto Glasgow pub (https://www.pprune.org/rotorheads/528850-police-helicopter-crashes-onto-glasgow-pub.html)

S Jones 30th Nov 2013 19:26

A local SBS user reported that his last contact was 22:21:49 at 725ft. Network shows last contact 75 feet 2224

Am I the only one who's seeing that and thinking that equates to a descent of 650 feet in little over 2 seconds?
That seems a bit more (or a lot, actually) than just falling at autorotation speed.

Wetbulb 30th Nov 2013 19:26

- Faster than normal descent.
- But slower than terminal velocity.

Vortex ring?

Nemrytter 30th Nov 2013 19:32

S Jones, that's two minutes - not two seconds.
To travel so far in 2 seconds you'd need to have a descent rate of something like 19,000fpm. Far faster than freefall would give (assuming you're not descending to begin with).

S Jones 30th Nov 2013 19:33

Nemrytter, Sorry, yes my mistake, you're right.

787-1 30th Nov 2013 19:46


from witness reports inside the pub, it seems to have been a 2 stage event, with the heli ending up the roof with more control than just gravity, followed shortly after by the wooden roof collapsing under the weight. So providing these witness reports are factual, some level of auto-rotation control was still possible. Pure gravity would have smashed right through the ceiling.
If thats the case, wouldn't the crew survive ?
Sounds like a high impact/heavy landing causing structural damage to the roof which subsequently failed.

Personally I would expect to survive a 7-8ft drop whilst strapped in / plus roof below you.

tartare 30th Nov 2013 20:20

The roof that the pilot landed on appears to be a flat structure from photos - am I right?
The reason I ask is that I wonder that given the darkness, would it have been immediately apparent from above that it was in fact a building and not just a dark open space.
Are NVGs used by pilots on this operation?
Power failure of some kind, rapid yaw, or pitch - possibly both, an attempt to regain control and rapidly look for somewhere to put the machine down?
What's the avoid curve for the EC135 T2?
I should add, I'm not inferring pilot error or blame in anyway.
It must have been nightmarish.

MightyGem 30th Nov 2013 20:26

Is it just me, or is anyone else getting fed up with the way that the local population; ie, members of the public, the Fire Brigade, Chief Police officers, MPs and anyone else given the chance, are bigging themselves up over this in that giving the impression that: a) how they all got together to overcome this disaster, and b) people elsewhere wouldn't have been able to. :ugh:

Rant over, chill….

staplefordheli 30th Nov 2013 20:27


Armchair_Ace
Tragedy & Emoticons
Thank you staplefordheli for taking the time to reply to my frustrated rant.
Your post on this thread about a dreadful accident, to be honest, really wound me up. To me it came across as "non-pilots, what do they know" & is an attitude that exists on & spoils this forum. Yours was simply the straw that broke the camel's back & I would have used any other had I come across them today. You seem to have a good knowledge of helicopter workings & your explanation of the bangs was very informative - much more useful than rolling eyes!
Ok point taken onboard

I think I should have perhaps explained rather than the emocon which was more aimed at those with a working knowledge of rotary AC or for that matter turbines and pistons

Bit akin to someone saying after a rail crash that the train driver appeared to have trouble steering if you know what I mean
Didn't want to be shot for being the messenger

barry lloyd 30th Nov 2013 20:43


Is it just me, or is anyone else getting fed up with the way that the local population; ie, members of the public, the Fire Brigade, Chief Police officers, MPs and anyone else given the chance, are bigging themselves up over this in that giving the impression that: a) how they all got together to overcome this disaster, and b) people elsewhere wouldn't have been able to.
As the son of a fire officer, yes. My father attended many large fires and other incidents during his career, but generally didn't speak about it very much. No disrespect is intended to anyone involved in the rescue and recovery operation; we hear and see so much about drunkenness and its attendant problems outside many of the UK's pubs today and it's particularly reassuring to see people helping each other in such distressing times, but this constant 'bigging up' of those involved is becoming a little tiresome.

S Jones 30th Nov 2013 20:44

MightyGem "Is it just me, or is anyone else getting fed up with the way that the local population; ie, members of the public, the Fire Brigade, Chief Police officers, MPs and anyone else given the chance, are bigging themselves up over this in that giving the impression that: a) how they all got together to overcome this disaster, and b) people elsewhere wouldn't have been able to.
Rant over, chill…. "


Hasn't bothered me. TBH it's heartening to know that most people there formed a human chain to rescue others, not knowing if the rest of the roof was going to cave in on them.

What did irk me was the dumb blonde Scottish female BBC reporter who spent most of this lunchtime drivelling. She'd run out of facts and was bottom-scraping for opinions. I half expected to see the landlord's dog being interviewed next. Overkill, get off the screen dear, my TV's starting to get your fizzog burnt into it.

Those people turn it into a freakshow. People died. Give us just the facts (I gave up correcting one paper from describing the fenestron in one photo as the EC135s "wheels"), and move on. Allow people to grieve.

ShyTorque 30th Nov 2013 20:49


But the engine intakes on the 135 are way inside the airframe, so that I think a yaw movement would have nearly no influence.
I'd agree but we really don't know. I don't think it's something to be ruled out of hand, because it's not something that would normally be tested on any helicopter, for obvious reasons.

jayteeto 30th Nov 2013 20:54

From 800ft at night, a low flat roof would easily be mistaken for a clear area. Flare and check height is equally difficult for an eol. You don't need to be that much in error to have a potentially fatal fall. All speculation from me, an ex police pilot with 7 years operating at night over a city. In my next 3 years flying an air ambulance I have discovered that minor bumps and falls can cause fatalities, life is so fickle, a simple wrong choice of seat in the bar decided people's fate.
This is a rumour network, some of us know 100% that certain contributors are talking real guff, however WE are speculating as well as them. More informed speculation, but still only opinion. Stop slagging people off for having an opinion. By all means correct errors.

ShyTorque 30th Nov 2013 20:56


Surely the idea that a chopper pilot would choose to land on the roof of a building when he could land on the ground, even a busy junction, is somewhat strange? Cars and pedestrians would be likely to have at least some chance of getting out of the way, whereas those in a building would not, not to mention the added danger to the crew if the roof gave way.

Also surely the C of G of this craft would mean it stays upright when the blades are seized?
I believe (from one photo I saw) that there is an area of open ground, albeit not very large, immediately to the rear of the pub. It's possible that this dark area was chosen but the dark coloured roof was indistinguishable from the open ground until too late to avoid.

We really can have no idea how a "stopped rotor" EC135 would fall to earth. Again, no-one has yet volunteered to be the test pilot for this.

East11 30th Nov 2013 20:59

@tartare

Lurker2500's google map link shows the aerial view and I bet from certain angles it would have looked just like road, esp at night.

Noticed some of the photos on the beeb showed bits of branch/tree on the roof of the pub, and again on the satellite view you can see trees on the adjacent plot, in fact growing out of the shell of the building.

Might give an idea of trajectory.

NorthernChappie 30th Nov 2013 21:00

Is it just me, or is anyone else getting fed up with the way that the local population; ie, members of the public, the Fire Brigade, Chief Police officers, MPs and anyone else given the chance, are bigging themselves up over this in that giving the impression that: a) how they all got together to overcome this disaster, and b) people elsewhere wouldn't have been able to.

Rant over, chill….


Yes - and they were ALL supposed to be at St Andrews Night Ball tonight - last one before independence vote so it was a big night for them. Friday night put an end to that for the emergency services chiefs and should have done for anyone else with a sense of decency. Apart from Salmond of course who is no doubt hooching it up having left the nippie sweetie in charge.

I'm sickened by some of the rhetoric today from politicians - all SNP regrettably and I am not particularly political by nature. I agree that exactly the same response would have happened anywhere else whether Scotland or the wider world.

Most of my PPL is done at another heli emergency base and based on the professionalism I see from those folks, I have nothing but respect and profound sadness tonight for the crew.

S Jones 30th Nov 2013 21:02

@Shy, there's a few spaces. Not sure how empty the car park to the north would have been though, going by the 120 customers in the bar.

http://img824.imageshack.us/img824/6643/lg6d.jpg

EDIT: added shot with pub unobscured.

ShyTorque 30th Nov 2013 21:03


What's the avoid curve for the EC135 T2?
As a performance Class A, twin engined aircraft, we can rest assured that normal police operational flight scenarios are not near the parameters. Both deliberately so and by their very nature.

zorab64 30th Nov 2013 21:05

lonewolf - your understanding of the implication is correct - i.e. most of the rotor inertia may have been "used" by the time of impact, hence very low rotor speed at the final stage.

Re inertia - most twin engine helicopters have low inertia rotor systems, as they're optimised for powered flight. As it's normal for such machines to stay powered in the event of a (very rare) single engine failure, the rotor systems will autorotate, but Nr tends to be a challenge to control (in a modern twin anyway). A single, such as B206, will have a rotor system that has a good deal of inertia should the (normally reliable) engine fail, and makes it relatively safe and easy to get into auto. I'm sure this debate has been debated & discussed in greater detail in rotorheads by experts such as Nick Lappos.

RotorRPM - to clarify, the tail rotor area, fin & horizontal stabilisers appear largely intact and a separate photo showing the fenestron itself, i.e. the fan, appeared mostly full of blades. I say "appeared" as I felt the angle was difficult to see if there were blades attached to the bit out of view.

S Jones 30th Nov 2013 21:06

I seem to recall in the Pete Barnes accident in January, someone was able to plot his course.
Is anyone able to find out the route SP99 took, as that could give an indication of where they were trying to reach.

Stu B 30th Nov 2013 21:18

Which direction was the aircraft approaching from? From that direction, would the nature of the building been obvious to the crew as being a busy bar, or perhaps apparently just an anonymous building with a flat roof, and more attractive as a landing point than a busy road - reports of groups of passers-by later helping with rescue suggests the street may have been quite busy.

Or, from the approach direction, would the path have had to pass over the bar to reach the apparently spacious crossroads, so that the aircraft may not have had enough energy to pass over the building to reach the junction (even by really milking the last of the energy form the rotor at the last moment to the point where flight could no longer be sustained?)

A very obstructed built-up area would be a very hostile environment to complete an engines-off landing even if full control was available and the crew may be unlikely to have the luxury of more than a "barely-suitable" option to try to get down into.


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