more on helicopter crash.

[The Other Mike]

A V S I M

It's someone sat indoors playing flying

[unknown]

OOI some of us fly other things too. This speculation is ridiculous and will achieve nothing - wait for those with access to the information to work out what happened.

[Nightjar]

On 10/12/2013 13:35, unknown wrote: ...

It won't solve the reason for the crash, but I disagree that it will achieve nothing. At the very least it gives those who do not know much about the subject some indication of what could not happen. On past performance, the full AAIB report could take anything up to a couple of years to appear.

Colin Bignell

[The Natural Philosopher]

And still be inconclusive.

Did you watch the series on air accident investigations a few years back? One crash they reckoned that almost certainly one instrument of a pair had duff wiring and they switched the good one off..but they never found the broken joint.

Or the chinook that hit a mountain. Why would the very experienced pilot pull up into cloud?

The official reason is still IIRC 'pilot error' but chinook pilots say that if the rotors went into dangerous overspeed due to a wide open throttle, that was the thing you would do...and this is not an unknown occurrence.

[Peter Parry]

Ask the hundreds of other very experienced pilots who discovered the perils of hard centred clouds. Controlled flight Into terrain even has its own acronym it is so common (CFIT).

[Nightjar]

One reason I had a radar altimeter fitted to one of my aircraft.

Colin Bignell

[Grimly Curmudgeon]

"Around this time, a witness described a noise like a loud ?misfiring car? followed by silence. He then saw the helicopter falling rapidly."

Flame out.

[Peter Parry]

In aircraft incidents it pays to be very cautious about witness descriptions. The brain tries to fit reality into its concept of what reality should be and the two are rarely the same.

For one classic incident I was involved with of controlled flight of a perfectly serviceable aircraft into a hill witnesses described the aircraft exploding in the air, burning in the air, tumbling. In fact almost anything except "flew into hill in straight and level flight" because "everyone knows" aircraft don't do that..

[John Williamson]

The preliminary report linked to ^ up there ^ says that it had 400 kg of fuel at departure from base and they drained 95 kg of fuel out of it at the investigation hangar. 95 kg of fuel is about 20% of a full load.

Basically, the report says they have no idea what caused the crash, as there was plenty of fuel on board, and they haven't yet found any mechanical faults that couldn't only have been caused by the impact.

[Nightjar]

On 10/12/2013 07:21, Windmill wrote: ...

Once the helicopter had been removed from the building, 95 litres of fuel were drained from the fuel system. No details are given of where it was found, but the two engine supply tanks between them hold about that much when full.

Colin Bignell

[Tim+]

Um, all the recent reports quite clearly state that 95L of fuel was drained from the tanks after the accident.

Do try and keep up if you want to add anything new to the speculation.

Tim

[Adrian]

Where's the fun in that?

[fred]

In article , tony sayer writes

A very active and informative discussion there, thanks for the link.

[Harry Bloomfield]

fred presented the following explanation :

The consensus seems to be, if I'm understanding it(?) that it was maybe confusion over fuel tanks and fuel transfer pumps and that it ran out of available fuel (?).

[fred]

In article , Harry Bloomfield writes

My impression was that they are simply throwing up possibilities for discussion without any real consensus as yet.

This one interested me:

"Don't know much about helicopters-I'm a fixed wing man myself, but my partner said to me today on my return home that the helicopter may have been making a strange noise quite a few miles east of the eventual crash site according to some local kids would be around the Uddingston-South Lanarkshire area Don't know how much cognisance should be made of this, but you never know.. "

Uddingston it is about eight miles East of the crash site which in turn is about a mile east of the helicopter's operating base.

No speculation into what that may mean about the incident is intended.

[Dave Liquorice]

95 l so not quite 95 kg.

But close enough. B-)

The fuel is also turbine fuel aka kerosene, parrafin etc. It's not that easy to light, it needs to be vaporised first, either by heat (on wick) or by atomisation through a nozzle.

Aye, the screwing up of transfer pumps is a possibilty but with 20 mins flying time on a full seperate supply tank to a single engine how does messing up transfer pumps kill both engines at the same time. Surely the pilot would have reported the earlier loss of an engine? In fact I don't think the regulations would have allowed him to fly over the city at night with only one engine, even along the river...

[Tim+]

That seems to be the "best guess" so far but hard to understand why an experienced pilot got confused in the first place.

Tim

[charles]

but if he was already over the city, he have to go somewhere.

[Andy Burns]

I've heard the phrase "Aviate, Navigate, Communicate" so reporting it is not at at the top of the list, but you'd think one of the police on board could report it to their control even if the pilot had his hands too full to report it ATC.

[Dave Liquorice]

And with seperate supply tanks with 20 mins flying time when full per engine how a fup up with transfer pumps could kill both engines at the same time I'm not sure. From brief reading of the tank system I'm not even sure that there is a pumped way of emptying either supply tank, it seems that the return is via spillways inside the combined tanks with the levels of said spillways different so one engine will die due to lack of fuel before the other.

Redundant systems seem to be fairly well thought out on this 'copter.