Was it a AW139 somewhere in Asia, probably Macao??

Building
 

Business took me away for a couple days, but I would like to publicly thank "CJ Romeo" and "Electric John" for their input, as well as "andrewruk" who sent me a PM.

I will defer to these folks as to the construction of the Clutha, as they know more of it than me, and f they say the roof was all wood then it is. As I said, all I had to go on were pics which weren't hi-res enough to be absolutely sure of what I saw and part my interpretation of them appears to have been wrong, which is shown in newer pics. My apologies, my experience is in the US and apparently it doesn't cross over here well where things are done differently.

Still, I think we all agree that this was a much stronger roof than usual which would have withstood a much harder impact without immediate failure than one would suppose, especially with the masonry wall they refer to inside, of which I was unaware prior to their posts. That changes a lot of things as far as strength and support issues go.

CJ Romeo is right about rooftop AC units, gravity does most of the work holding them in place and little other fastening is needed or done, so if any part of the A/C struck one it would not have presented much of an obstacle.

One last point as to noise of impact. Being large and flat, a roof when struck acts much like a drumhead, emitting a low-ish frequency 'boom' when something strikes it. I've heard that 3 times when crane rigging failed and the load dropped. Once I was on the roof when an AC unit twice the size of the one on the Clutha dropped from about 20 ft- luckily I was at the other end, but it felt like an earthquake under my feet! Also luckily it didn't go through but it made one heck of a dent. And then once I was 50 ft away from a full concrete truck that overturned on a concrete bridge and I heard absolutely nothing- very strange indeed as others say they looked only when thy heard it impact the barrier and then flip, and that it was a loud event. I can't explain that at all but I got the driver out safely.... Life is indeed strange!

I will leave the thread to others from this point on and comment only via PM to those who contact me to keep the clutter down. May we learn what can be learned and not ever need another thread like this again.

The Scottish Daily Record reported

I am sure one of the Highland newspapers said that they had been taking part in a search near Inverness earlier in the day, refuelled and returned to base and changed crew.

SASless, this isn't a very useful attempt at analysis.

Bar had patrons, talk, noise, a band, and the acoustic buffer of walls and a roof to mute any sound form the outside -- be it a car, helicopter, or an elephant's mating call.

Bar patrons' attention was most likely on what they were doing, or the lovely pair on that gal over there ... :E ... I'll venture a guess that they were not silent, ears atwitch, listening for a helicopter engine sound/noise.

With the speed at which this event looks to have taken place, any noise form above would first be an interruption to what they were doing, followed by a "what's that noise" sort of response.

Their alert cue to the presence of an unexpected helicopter was the thump on the roof. Attention getter, no question.

What the bar patrons didn't hear in terms of engine noise is irrelevant.

Their attention was not on what was outside and above them until after the thump.

By the way, I am pretty sure you are aware that the first cue most of us on the ground have of a helicopter flying nearby or overhead is rotor noise, not engine noise.

The T/R malfunction videos posted, the one in NY and the one that disappears behind the trees, shed some light on what can be walked away from, and give some weight to TC's point on the last phase of this descent being high RoD ... since they didn't walk away from it.

I confess to a degree of surprise at no Special Bulletin from AAIB a week on. As with Sumburgh, and in view of the similarly high profile nature of the type/role, I did expect an early indicator to give reassurance (assuming reassurance is in order). The statement 'both engines delivering power at time of impact' re Sumburgh did much to dispel rumours about fuel starvation or MGB/other major component failure being the root cause (whilst still leaving proper space for the detailed report to find in due course on root/contributory causes and aggravatng conditions).

Other posters have referred to the 'process of elimination' in investigation, and some insight from the AAIB into what can be/has been positively eliminated so far would be useful.

The current complete vacuum is creating some pretty unhelpful 'heat without light'

In the course of preparing for various BBC appearances last weekend, I asked AAIB if they could give me any idea of when we might expect an interim report.

Their reply surprised me. They are preparing such a report, they said, but they will not necessarily publish it. Apparently they only publish such reports when there is some action, such as an AD, perhaps, that operators and manufacturers are required to take.

I was left to infer from this that, at the time of the conversation, no such action had been identified, and that an interim report was not expected to be published.

Airsound: received but, as AAIB S7/2013 said, "This bulletin provides an update on the significant investigation findings to date."

Far from announcing an AD or other essential action for operators, this special bulletin was, in effect, a statement that any requirement for immediate action by the manufacturer/operators had already been (to all intents and purposes) eliminated. Which seems to conflict with the briefing you were given.

Lone,

Open thine eyes....and ears....the helicopter was inside the Pub.

Ever been next to a crashed helicopter and wondered how long the engine would continue to run? Been there...done that....and shut off the Main Fuel Switch to hasten getting the thing to quieten down.

Need I post some videos to prove my point?

Absolutely.....the Bar Patrons inside...would never hear the Engines outside....but that was only half the situation in this case as the Helicopter wound up smack dab in the middle of things inside the Pub.....and after the crashing of Timbers and the Band shutting down....there is a good likelihood someone would have heard the Turbine Engine(s) if they were still operating.

As I noted....there are numerous reasons why they would not be running post Crash....but whether they were or were not is relevant to the investigation.

I am merely stating there is no evidence in the public domain that indicates they were running.....thus the assumption can only be they were not.

AAIB will tell us one day with some certainty whether they were or were not operating.....I hope.

FFF. I don't disagree with you - that was what surprised me. Maybe it was a question of semantics, and I should have asked specifically about a Special Bulletin.

EASA AD 2013-0289-E: Eurocopter Deutschland EC 135 and EC 635 helicopters: Fuselage - Rear Structure / Ring Frame - Inspection


http://www.caa.co.uk/docs/33/2013120...D20130289E.pdf

I'm told that a Southern EMS operator has been told that it is "unlikely to be the rotor mast - new rumour is fuel." That was not from the AAIB but from an organisation intimately involved with its manufacture ;)

If memory serves, wasn't there an incident in Wisconsin concerning the FADEC? Where one throttle was found at idle after the crash? Maybe someone has a better memory.

Hopefully just mere coincidence.

They've given it 50hrs !

SASless, I see your point, thanks.

As helicopter comes through the roof your point was that "I heard the engine running" observation isn't there. I didn't read it that way, thanks for recaging my gyro there. :ok:

Whether or not engines "quit in flight as the event began or as the trigger to the event" versus "were shut off on the way down" remains unknown.

Paco,


CHI08FA128

Thanks for that - interesting that they can use the NVRAM

I am not a helicopter pilot and welcome criticism.

(1) An unknown roof is not the best place to land. No evidence the aircraft was changing direction to the adjacent roadway.

(2) A great deal of kinetic energy was dissipated rupturing substantial and close floor joists in the compound roof. An internal masonry wall may have been involved. The roof was struck with considerable force.

(3) No evidence the rotors were turning at impact. The engines were not running.

(1) The helicopter was intact descending very fast but not in free fall. By the time the pilot stopped the rolling and rotation ("tumbling") reported by witnesses he lacked height to stabilize autorotation and regain full control.

(2) The immediate forced landing was precipitated by a sudden failure with no warning.

(3) Witnesses heard unusual mechanical noises earlier prior.

(4) There is an AD on the ring frame holding the fenestron to the boom.

(5) Photos of the scene show the fenestron broken off?

Edit: http://www.caa.co.uk/docs/33/2013120...D20130289E.pdf

Paco, it was clear to every operator very soon after the incident that it wasn't the mast, as clear as it is that the engines weren't running when the ac was embedded in the pub. As for the fuel rumour, what did your source hint at?

a. Lack of?
b. Contamination?
c. Activation of fuel valve?
d. Some other starvation?

Mmmm;
a. Covered earlier many times!
b. Despite all the checks and filters?
c. Inadvertent, Intentional (because of an engine bay fire for example) or some form of wiggly amp malfunction.
d. Such as?

Theories are all well and good, as are "I heard it froms", but please have some form of reasoning behind them otherwise they are just "how abouts"!

Ornis,

The AAIB Representative did make an assertive comment confirming the aircraft was intact prior to impact and that all components were accounted for. That statement suggests there is no obvious evidence to suggest the Fenstron had separated from the aircraft prior to impact.

The EC AD results from a Pilot's Post Flight Inspection discovery of the cracking between the Rivets and is not necessarily related to this event.

The fenestron is in the photos so did not depart the aircraft in flight. If the attachment is (badly) weakened the fenestron would be more likely to break off in the impact.

Naturally this emergency AD is not a consequence of this accident but it's relevant until shown otherwise.

SS, if you're in the mood to dismiss various hypothesis, how about a Kegworth? In other words, No 1 starts failing/fails, No 2 is shut down.