Airpolice, It's a bit more complicated than that.

If you stretch a coil spring it will return when released, if in the soft state, illuminated, it will not return to the original length. If the impact is severe it will fracture in both cases.
Metallurgical examination will determine whether it was hot or cold when the fracture occurred.

That's assuming they are bulbs and not LEDs!

Comes with free Anorak!

https://encrypted-tbn1.gstatic.com/i...nCxcEQzG_vRm0u

Haha wondered how long it would take. I mean what would I know I am just a fixed wing Pilot!
I will find out on Monday if they are LEDs on the real thing.

Extensive analysis of all "blue light" radio traffic at the time, not just the stuff involving the helicopter, will be required to make an educated guess at what was going on that just might have got their attention.

Little things, like which division the crew were listening to, might point at what they were up to, just prior to impact.

Whether they were in fact returning to base, or looking at a job/potential job, might never be established.

At least the MASTER CAUTION are 4 bulbs, just changed one :)

skadi

Still harping on about fuel
 

Could manoeuvering the aircraft to transition from the cruise in preparation for landing not cause fuel to overflow from the supply tanks back into the main?

Rotor brake?
 

I've read the initial CAA stuff. It appears that a serviceable helicopter with its rotors stopped crashed onto a pub roof.

I know what happens if the transmission fails (catastrophic in most cases). Engine problems seem ruled out by the initial report (as does fuel starvation) and by the knowledge that pilots train for exactly that.

I'm therefore left with one thing that could conceivably cause the accident as described, and that is the rotor brake. I'm not familiar with the EC135 rotor brake, so I don't know what conditions could cause (or for that matter prevent) rotor brake operation in flight However, On the current evidence (not the tabloid fluff but the CAA) I'm left with a possibility that fits the known circumstances.

Any thoughts out there?

That tiny thing could not stop a driven rotor! It even works hard to stop it after normal shutdown. :E

skadi

Rustchaser

The AAIB report says something along the lines of "no evidence of major disruption to either engine"? That's not necessarily the same as "engine problems seem ruled out".

I'm afraid we are all in the dark here, and that is very likely to remain the case until a report is published.

Falcon #1833 - Your questions have been mostly answered by others but, yes, Police Pilots are used to launching for a job, and being re-tasked in flight to somewhere else, at any stage in the flight. One does not generally brief for a flight, you brief for the whole shift, since you never know what/where you're going to go to - an update brief will normally just relate to an unexpected pax or extra fuel (endurance) required, or possibly a longer range unusual task, most likely to be slow-time & planned, rather than immediate/reactionary. Almost every flight is a constant re-prioritising exercise juggling tasks, distance, weather, fuel, alternate base/fuel, etc.

As has also been intimated by others, whilst you can reduce fuel consumption (e.g. sitting in the hover into a 20-30kt wind for 20 mins) that period seldom lasts long enough to make more than 5 mins difference to a typical 1:45 - 2:00 (night) endurance, since the rest of the time you're normally rattling along at Max Cont to get to/from jobs as quickly as possible - it generally works out at a very steady 200kg/hr for airborne or ground calculation purposes.


Rustchaser - skadi is correct, and if you read the thread in full, you'll see that rotor brake theories have been discounted by numerous posts early on. In any event, the 135 rotor brake requires a very conscious decision to pull an overhead lever out of its stowed position and apply it (FLM says below 50%). You'll find most pilots are uncomfortable enough about pulling it on at 50%, & leaving it to stop, as part of the rotor brake proving process when the pads or disc are changed!

Still harping on about fuel
 

Thanks Zorab.
You will have gathered that I am still fixated on fuel as the cause!
Given that fuel would certainly have to be on the prime suspects list, I am of the view that the AAIB would have drained the entire system at the scene Leaving aside any health and safety concerns about transporting the wreckage containng fuel, the risks of any leakage in transit compromising the evidence would not have been acceptable. The subsequent Eurocopter statement was in any event unambiguous, so it would seem that the entire contents were 95 litres.
As you appreciate, this is below the MLA for this aircraft flying at night, so even if you do not believe that it caused the accident, fuel was problematically low, in a way which would seem uncharacteristic of the pilot. Quite how it came to be so low, when he had passed up the opportunity to refuel at EGPH on the way home, needs to be understood, and for me the explanation is clear, faulty readings from the fuel probes.
The other significance of the fuel system contents being only 95 litres would be that in ordinary course, the main tank would have been empty, and indeed even the supply tanks would only be part full . The maintank would in fact have been empty for several minutes before the accident.
As I understand it, there are handling restrictions on the aircraft at low fuel levels, connected, amongst other things,with the fact that fuel can still be displaced from the supply tank overflow fences into the main tank. But if the fuel gauge was telling the pilot he was not in this zone, could it be that in the transition from the cruise in preparation for landing, fuel spilled out of the supply tanks into the main? Given that the main was empty, the spilled fuel would be difficult for the transfer pumps to capture and return to the supply tanks, and they certainly would not likely be able to return it to the supply tanks in the same quantities as it had left, so the design assymetry of the supply tanks could have been lost.
More speculation, I know, but what do you think?

Falcon 900?
 

Sir, (with respect) Is it fair to say that you have never flown this (or any other) helicopter?

If this accident was caused by fuel exhaustion (or starvation) the very fine pilot at the controls (and he really was a top guy) would have auto-rotated, taking extreme care to monitor and maintain MR speed.. even faced with the usual inner-city low-level difficulties.

How then would you explain the (alleged) stationary MR blades on the accident aircraft?

Cheers, TP

Sparks and bangs
 

Have we any information regarding sparks and bangs emanating from the helicopter?

If it turns out to be fact my best guess that a relight was attempted by the captain or due to the change in pitch providing the transfer pumps with a small amount of fuel.

What is the SOP regarding the use of igniters?

What do you mean by use of igniters?

[QUOTEWhat do you mean by use of igniters?

[/QUOTE]

Fixed wing only here. In bad wx rain, engine intake icing, severe turbulence and low level, sop was igniters on.

This would help prevent a flame out or even a re-light.

Partial Relight
 

If a partial restart occurred and failed it must be very difficult for the captain to carry out the correct drills and control inputs. Even the best of the best would not have a clue what was happening.

Robin

If an engine flamed out at relatively low level over an urban area, I can't conceive of a situation where I would remain at low level whilst attempting a relight. Nor would I be attempting a relight whilst in autorotation!

Neither of those scenarios represent 'flying the aircraft' in any way shape or form!

Even on fixed wing, it's like saying one of the three pilots of the BA 777 that crashed at Heathrow a few years ago should have tried to relight the engines!:rolleyes:

I can't be at all sure that the witness statements are consistent with a helicopter simply running out of gas?

I can't comment on the issue of continuous ignition on an EC135 as I don't fly them, but I can only imagine it to be an unlikely configuration?