Go Back  PPRuNe Forums > Aircrew Forums > Rotorheads
Reload this Page >

Police helicopter crashes onto Glasgow pub

Rotorheads A haven for helicopter professionals to discuss the things that affect them

Police helicopter crashes onto Glasgow pub

Old 18th Jan 2014, 14:12
  #1801 (permalink)  
 
Join Date: May 2007
Location: Banished (twice) to the pointless forest
Posts: 1,555
Shy, but only if it is broken.
airpolice is offline  
Old 18th Jan 2014, 14:55
  #1802 (permalink)  
 
Join Date: Dec 2007
Location: UK
Age: 76
Posts: 158
Coil spacings

A stretched filament will have increased coil spacings from impact if illuminated, it is in a soft state.
Robin400 is offline  
Old 18th Jan 2014, 15:09
  #1803 (permalink)  

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 12,765
Robin, I agree, a non-illuminated filament is relatively brittle and likely to snap under impact, just as if it failed in normal service due to old age and vibration. A lit one is much more flexible and more likely to be displaced from its normal position in the envelope under a heavy impact.
ShyTorque is offline  
Old 18th Jan 2014, 15:09
  #1804 (permalink)  
 
Join Date: May 2007
Location: Banished (twice) to the pointless forest
Posts: 1,555
So, the state of the bulbs might tell us nothing.

If it is intact, then either it was on, and survived the impact, or it was off at impact, and survived.
airpolice is offline  
Old 18th Jan 2014, 15:19
  #1805 (permalink)  

Avoid imitations
 
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 12,765
Airpolice, It's a bit more complicated than that.
ShyTorque is offline  
Old 18th Jan 2014, 15:23
  #1806 (permalink)  
 
Join Date: Dec 2007
Location: UK
Age: 76
Posts: 158
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.

Last edited by Robin400; 18th Jan 2014 at 15:52.
Robin400 is offline  
Old 18th Jan 2014, 15:54
  #1807 (permalink)  
 
Join Date: Jul 2013
Location: Uk
Age: 63
Posts: 59
That's assuming they are bulbs and not LEDs!
PieChaser is offline  
Old 18th Jan 2014, 17:54
  #1808 (permalink)  
 
Join Date: Nov 2006
Location: After all, what’s more important than proving to someone on the internet that they’re wrong? - Manson
Posts: 1,550
Warnings panel for Eurocopter EC-135, consisting on the following pieces:
1 front panel size 266x38 mm (black)
1 auxiliary panel
14 annunciators

Components needed (optional):
2 Rafi 19H tactile switches
4 3mm high efficiency green leds
4 3mm high efficiency red leds
20 3mm high efficiency yellow leds
Welcome to Hispapanels SL website. We are a company that designs and manufactures panels for flight simulation.
Comes with free Anorak!

RVDT is offline  
Old 18th Jan 2014, 18:11
  #1809 (permalink)  
 
Join Date: Jul 2013
Location: Uk
Age: 63
Posts: 59
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.
PieChaser is offline  
Old 18th Jan 2014, 19:30
  #1810 (permalink)  
 
Join Date: May 2007
Location: Banished (twice) to the pointless forest
Posts: 1,555
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.
airpolice is offline  
Old 19th Jan 2014, 08:38
  #1811 (permalink)  
 
Join Date: Feb 2006
Location: On the big blue planet
Posts: 941
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.
At least the MASTER CAUTION are 4 bulbs, just changed one

skadi
skadi is offline  
Old 19th Jan 2014, 15:19
  #1812 (permalink)  
 
Join Date: Jan 2008
Location: glasgow
Posts: 179
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?
falcon900 is offline  
Old 19th Jan 2014, 22:49
  #1813 (permalink)  
 
Join Date: Jan 2014
Location: Liverpool
Posts: 1
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?
Rustchaser is offline  
Old 20th Jan 2014, 05:33
  #1814 (permalink)  
 
Join Date: Feb 2006
Location: On the big blue planet
Posts: 941
I'm therefore left with one thing that could conceivably cause the accident as described, and that is the rotor brake.
That tiny thing could not stop a driven rotor! It even works hard to stop it after normal shutdown.

skadi
skadi is offline  
Old 20th Jan 2014, 08:47
  #1815 (permalink)  
 
Join Date: Jul 2000
Location: Nova
Posts: 1,241
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.
Tandemrotor is offline  
Old 20th Jan 2014, 10:59
  #1816 (permalink)  
 
Join Date: Nov 2004
Location: UK
Posts: 291
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!
zorab64 is offline  
Old 20th Jan 2014, 11:39
  #1817 (permalink)  
 
Join Date: Jan 2008
Location: glasgow
Posts: 179
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?
falcon900 is offline  
Old 20th Jan 2014, 12:19
  #1818 (permalink)  

Purveyor of Egg Liqueur to Lucifer
 
Join Date: Nov 2002
Location: Alles über die platz
Posts: 4,617
SilsoeSid is offline  
Old 20th Jan 2014, 12:37
  #1819 (permalink)  
 
Join Date: Jul 2011
Location: Offshore
Age: 70
Posts: 143
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
talkpedlar is offline  
Old 20th Jan 2014, 14:25
  #1820 (permalink)  
 
Join Date: Dec 2007
Location: UK
Age: 76
Posts: 158
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?
Robin400 is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.