Technet101 asked:
"Given a choice....of either landing on top of a building or taking the aircraft to the street (neither of which are first choices), I think the Street would be the choice most of us would have made."

People in the street would steer me away. A rooftop might appear to present a less dangerous option than exposed people. Who knew the roof would collapse into a crowd?
Sometimes you have no good choices and take the lesser of the bad ones.

The crane lift today?
 

Apart from the obvious visible damage it didn't seem to be a case of total destruction of the main cabin? Like I said before let's wait for the guys at Farnborough to come up with the answers, this sadly isn't the 1st Police Helicopter they have seen in the last 3 years

Thomas Coupling,

Reference your comment about fuel.

I too flew the early T1 and T2 CDS and CPDS in the Police role with a MAUM of 2720kg and 2835kg.

The newer T2+ has a MAUM of 2910kg and T2e 2950kg so even though the aircraft have got fatter the MAUM has increased.

G-SPAO (if that is the aircraft involved) is listed as a T2+ so would have the increased AUM so would probably be able to carry a greater fuel load than we were used to. Also it was on low skid and no Mac Pod so may have been lighter.

I'm not saying fuel was not a possible cause but as previously mentioned - there would have been plenty of warnings to say it was time to go home.

It was stated in the media that the AAIB investigation may take up to a year before publication of a formal report (as we know, this isn't an unusual length of time because of the fine detail they must go into).

At the moment, there are many folks with no knowledge of helicopters who are hurting very badly indeed. Understandably so. Do we, as a profession, not owe them some form of reasonable explanation or understanding as to why why their loved ones are gone forever in this tragic accident?

Or do we, as a profession, simply clam up and tell them to wind their necks in and wait a year, allowing others with no relevant knowledge to be paraded in the main media and spout what is often ignorant rubbish? I think I have a good idea what the bereaved would prefer.

One reason may be that because the AAIB reports take time to be published people need to think things through so that, heaven forfend, they are faced with a similar situation they may have a little extra knowledge to help prevent a repeat of whatever event is under discussion. It's a bit like a staff room chat on line mulling over events of the day. There will always be those who post who haven't a clue but still consider that they should pontificate on events but the ones who really know what they are talking about have the facility to correct errors.

G-CPTN,
No Mayday call? Pilot busy. One of my Army Instructors used to say that one of the best Mayday calls you can make will be from a phone box, (this was in the days before mobiles), stating that you are safely on the ground and to send a truck to the following location to collect the wreckage. There's no point in a word perfect Mayday call whilst forgetting to fly the aircraft or deal with the problem.

Sid,
Agree about the engines - after the 2002 Strathclyde crash I seem to recall the AAIB report stating that after getting out of the cockpit, the pilot had to reach back in to shut off the engines which were still running. But, as you well know, shutting them down with the collective throttles will only take them to a low idle. There's a button to press or catch to move, depending on type, to shut the fuel off completely. Taking your hand off the collective to move 4 switch guards and operate the engine main switches would be difficult to say the least in such a short space of time. The fire bottle switches are even further from the collective.

Shy,
One of the issues about "getting the information out there" is that as soon as something like this happens we are told by management "don't talk to the press" - who naturally, if they can't find anyone who does know what they are talking about drag out the usual "experts". I was very impressed by Mr Miller from the AAIB today though!

Not wanting to get involved in any speculation about the reasons but that is also what came to my mind. Was a bit surprised by numerous statements concluding from the shape of the airframe that it was a rather benign 'arrival'.
The EC135 has quite some massive roll-over frames built into the primary structure. To bend it in a way like you see in the pictures will surely take significant impact force. Never ever was that a soft landing followed by a slow breaking through the Roof.

Oldbeefer - if we did what you suggested, there would be no -Pprune now would there?:=

Nomorehelosfor me: have you been infarcated yet !!!:ooh::ooh::D

Floaternorthwest: There once was a naval aviator who ferried underslung loads from shore to ship. He did this time and time again until the co-pilot mentioned the fuel caption was on. The trip continued until the booster pump pressure lights illuminated as well, the trip continued until No1 engine flamed out and they crashed because he didnt pickle the load. The captain died and the co-pilot is a paraplegic. Captions, gongs, sirens all to no avail to a pilot under stress..... But yes, I think in this instance it is a little far fetched that fuel starvation is the culprit, but just airing the option.....;)

Mr Millar from the AAIB concludes the a'c's flight path from start to finish was vertical, not diagonal. This may suggest that something so catastrophic happened that the pilot had no option but to lower the lever and descend. He couldn't "run away" from the problem into fwd flight. To me that means his options were limited or nil. To me that means a catastrophic failure in or around the gearbox area and I base this solely on the condition of the RB's on touch down..

Vortex ring??

This statement may explain why customers in the pub experienced the ceiling coming down in a number of stages...

BBC News - Glasgow helicopter crash: Clutha bar building 'hampered recovery work'

Suggestion to the moderators: Since this is a rumour network, could it be a condition on the forum rules that the decrying of discussions about possible causes (aka speculation) is not allowed. That would at least allow such posts to be deleted (thus shortening this thread by about 50%) and sparing us from those who want to tell us that we shouldn't be speculating, just because they like the sound of their own mawkish voices. We get the same old dreary BS EVERY TIME there is an accident thread, typically from new or limited posters, and I am starting to find it pretty tedious.


You should see the posts that have been moderated! Unfortunately there are often posts which both call for no discussion and then add to the debate; only very rarely does a post get altered by a mod, it is usually a complete deletion.

Splot

As a former fire-fighter and helicopter pilot I find it difficult to follow the thread, and I certainly don't want to add to any speculation, but be aware of the sad fact that it may have been necessary to cut the forward section of the cabin away to remove the crew, which may distort the perceived amount of damage sustained by the actual accident.

The pictures from when they pulled out the chopper look more like a 30 degree nose down attitude while hitting the building hard. Sounds unlikely crew would die from hovering, landing and then crashing 2 meters down into the structure.

Indeed! . . .

See

BBC News - Glasgow helicopter crash: Clutha bar building 'hampered recovery work'

which shows the internal layout of the Clutha, some way down the page.

The small hole in the roof that can be seen in the earlier overhead vid of the aircraft being lifted must be just in front of the stage. Consistent with the reports of "the band bringing the roof down" a very short time before the big impact?

Glasgow Helo Crash
 

On the evidence so far available, it would appear the chopper went down in a straight vertical descent, meaning it had virtually NIL horizontal velocity. Assuming a weight of 2.5t a descent from 300m,and an intial impact absorption/stopping distance of 5m, the dynamic impact force would have been close to 150tons. To put it another way, a weight increase of 60 fold. With a frontal area of say 4 sq.m., this would have equated to an impact force of nearly 40tons per square meter.
Perhaps this helps to explain the apparent damage to the roof of the building and the disposition of the wreckage.

Agreed. The pattern of destruction appears consistent with the ceiling/roof collapse in the side of the bar where the band was playing occurring a little after the aircraft punched through the roof into the other side.

The aerial views video (on the BBC news site) show me a roofstructure of the pub that has exactly the same colour and appearance as the (blacktop) area around the pub. Although I'm not familiar with the immediate surroundings of this area (and ofcourse I don't know how the street looked at that time of night), I find it totally believable that the crew (under stress of the moment, and in night conditions) had a hard time to distinguish rooftop from blacktop around it. What I mean to say is...it may not have been the intention to land it on the rooftop; in fact, maybe they didn't initially realize they were aiming for a rooftop.
Auto's in the dark are no easy thing to do. Mr. Miller confirmed that the helicopter made a vertical descend to 'impact'.
I would make it top priority in my autorotation to get as little forward speed as possible...especially in this area where there is not much space (if any) for a running landing. They may have ended their flare at an altitude a little higher than originally anticipated (depth perception in the dark/goggles is not an easy feat.)
Nr might have been traded off during the final (vertical) descend while trying to control the RoD.

If the aircraft was subject to a frontal deceleration of 60g on the forward fuselage, I'm surprised that the engines, drive train and other heavy stuff on top stayed attached.

what would have to happen to prevent an autorotation? i.e. loss of collective. Could this take place simultaneously with a gearbox failure?