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Police helicopter crash in Glasgow city centre

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  • Police helicopter crash in Glasgow city centre

    A police Eurocopter EC-135 crashed around 22:30 last night through the roof of a pub in Glasgow. Currently the 3 crew - 2 police officers and a pilot - and 5 on the ground are confirmed dead, still 14 in hospital with serious injuries and some still missing.

    Apparently the pub had about 120 people in at the time, most of whom merely describe hearing a bang and having parts of the ceiling come down.

    According to witnesses on TV the engine made 'strange sounds' and the rotors stopped and the helicopter came down nose-first into the roof. The blades are described by a former pilot/trainer as being intact, indicating very low rotor speed. The pub is next to the river, no information whether the pilot was trying to ditch.

    It doesn't appear that there was any fire as a result.

    BBC News: http://www.bbc.co.uk/news/uk-scotland-25165894

  • #2
    transmission failure?

    Comment


    • #3
      Ugh. Awful.
      I do work for a domestic US airline, and it should be noted that I do not represent such airline, or any airline. My opinions are mine alone, and aren't reflective of anything but my own knowledge, or what I am trying to learn. At no time will I discuss my specific airline, internal policies, or any such info.

      Comment


      • #4
        Originally posted by Evan View Post
        transmission failure?
        Very likely. The description sounds like a total gearbox failure. RIP all concerned and especially my emergency service colleagues.
        If it 'ain't broken........ Don't try to mend it !

        Comment


        • #5
          Investigators have found no evidence of mechanical fault, but neither main nor tail rotors were rotating on impact, and it had 95 litres of fuel on board.

          From the report:
          "Initial assessment provided no evidence of major mechanical disruption of either engine and indicated that the main rotor gearbox was capable of providing drive from the No 2 engine power turbine to the main rotor and to the fenestron drive shaft.

          "Clear impact distortion of the structure had caused a splined shaft on the drive train from No 1 engine to disengage, preventing a similar continuity check."

          There were no flight recorders.

          Source: http://www.bbc.co.uk/news/uk-scotlan...-west-25306936

          Also, the firm running the emergency services helicopters have grounded all EC-135s, although Eurocopter say they are not telling other operators to ground their aircraft.

          Source: http://www.bbc.co.uk/news/uk-scotlan...-west-25353001

          Comment


          • #6
            Reports of sounds like a loud backfiring car !

            Bird strike maybe into an engine....but the other engine should be able to maintain power ? What else could cause such a sudden loss of power. Fuel flow maybe ?
            So many maybe's !
            If it 'ain't broken........ Don't try to mend it !

            Comment


            • #7
              Originally posted by brianw999 View Post
              Reports of sounds like a loud backfiring car !

              Bird strike maybe into an engine....but the other engine should be able to maintain power ? What else could cause such a sudden loss of power.
              Even full loss of power should not cause the rotor to stop turning.
              Ever heard of the autorotation?

              --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
              --- Defend what you say with arguments, not by imposing your credentials ---

              Comment


              • #8
                Originally posted by Gabriel View Post
                Even full loss of power should not cause the rotor to stop turning.
                Ever heard of the autorotation?
                That's what's so baffling about this incident. If he did suffer a sudden power loss then an autorotation should have been possible. But the report states that the aircraft came down like a lift with little or no forward speed. The rotors are still firmly attached to the hub. If they had been turning on impact then they would have sheared at the hub and there would almost certainly have been damage to the tail boom. It seems like the rotor blades have been cleanly cut off to aid recovery of the wreckage and the tail boom is remarkably intact. Very puzzling. I've been around helicopters for some years now and this accident has got me foxed.
                If it 'ain't broken........ Don't try to mend it !

                Comment


                • #9
                  There maybe are some similarities between this incident and the crash of a Eurocopter AS350 in Las Vegas in 2003, as outlined here: http://libraryonline.erau.edu/online...s/AAR13-01.pdf

                  In that accident, a bolt in the rotor-control linkage came out, instantly rendering the helicopter uncontrollable, resulting in a crash.
                  Be alert! America needs more lerts.

                  Eric Law

                  Comment


                  • #10
                    Perhaps the pilot had some medical issue? They do fly with a crew of one pilot and then medics or law enforcement don't they Brian?

                    Autorotation over any urban area is still going to result in some tragedy unless you are very lucky or skilled and can see.
                    Live, from a grassy knoll somewhere near you.

                    Comment


                    • #11
                      Originally posted by guamainiac View Post
                      Perhaps the pilot had some medical issue? They do fly with a crew of one pilot and then medics or law enforcement don't they Brian?

                      Autorotation over any urban area is still going to result in some tragedy unless you are very lucky or skilled and can see.
                      A medical issue would not have caused the rotors to stop though.
                      Police helicopters in the UK fly with a single pilot and as far as I am aware medevac helicopters also only require 1 pilot. My local service has just started night flying using some very trick night vision equipment but they have a company policy (Medical/Police Aviation Services) of 2 pilots for night ops. This has meant that they have had to re-equip with a lightened version of the MD 902 to be able to carry the extra weight.

                      In July 1998 the Kent Air Ambulance AS 355 Ecuriel G-MASK crashed near Rochester with all three crew losing their lives after striking a cable. The subsequent AAIB investigation included a recommendation that all low flying emergency service helicopters be equipped with upper and lower cable cutters. Incredibly, this remained a recommendation and not a requirement. Most aircraft in service today still do not have cable cutters fitted. The cost to retro fit is said to be around 20,000 per aircraft.

                      I'm not suggesting that cables had any involvement in the Glasgow incident. In the absence of any gearbox transmission failure then the rotor hub becomes the focus of attention.

                      As far as autorotation is concerned, the aircraft was fairly low and would probably not have had time to set up an autorotate glide.
                      If it 'ain't broken........ Don't try to mend it !

                      Comment


                      • #12
                        Originally posted by brianw999 View Post
                        As far as autorotation is concerned, the aircraft was fairly low and would probably not have had time to set up an autorotate glide.
                        Just for the record, I didn't mean that an autorotation would have been successfull in this case. Just that a loss of power doesn't cause the rotor to stop rotating, as proved by the mere existance of autorotation.

                        In fact, it's very hard to stop a rotor. Typically a rotor will brake whatever tries to stop it or, if that thing is too tough, it will brake itself. It's very strange to see an intact rotor after an helicopter crash.

                        The only thing that reliablily stop a rotor without braking it is air: make the rotor consume more power than you are giving it, and it will slow down very very fast. But to do that you need to increase the pitch of the rotor and, AFAIK, in modern helicopters the speed of the rotor is controlled by a governol or similar that will automatically reduce the pitch if the speed descends below the "setpoint". More or less similar to the constant-speed, variable-pitch proppellers in airplanes.

                        --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                        --- Defend what you say with arguments, not by imposing your credentials ---

                        Comment


                        • #13
                          Two air ambulance EC135s have now been grounded after a fault has been found with the indicator system for the fuel system, meaning it is giving unreliable fuel information.

                          Source: http://www.bbc.co.uk/news/uk-england-25361925

                          Also, the other emergency helicopters previously grounded after this fault was found are back in operation.

                          Can't see that this is related to the crash though as there was 95 litres of fuel in the tanks, so it hadn't run out while still indicating fuel on board. Unless the systems thought it was empty and stopped pumping fuel to the engine?

                          Even if the engines cut out through fuel exhaustion though, surely that wouldn't prevent autorotation and stop the rotors?

                          I don't really know much about autorotation. Does it require forward motion to keep air flowing through the rotors and keep them turning?

                          Comment


                          • #14
                            Originally posted by sjwk View Post
                            Even if the engines cut out through fuel exhaustion though, surely that wouldn't prevent autorotation and stop the rotors?
                            Correct.

                            I don't really know much about autorotation. Does it require forward motion to keep air flowing through the rotors and keep them turning?
                            In theory, yes. But you don't have enough energy to flare and land.

                            If you lose power during stationary flight, you better:
                            a) Be very very low (a few feet) so either the landing is survivable even without pilot intervention or you can use the inertia of the turning rotor to increase pitch and cushion the landing.
                            b) Be quite high, put the collective fully down to initiate a stationary autorotation, pull the cyclic forward to lower the nose and increase speed to best autorotation speed, and then estabilsh and stabilize in a standard forward autorotation.

                            This height-speed curve is called "the dead man's curve" for a reason. Lose power in the red zone and you are ad ead man. That's why stationary flight in single-engine helicopters done either at "safe drop" heights or quite high.

                            But, in any event, if you are well inside the red zone (say stationary flight at 200ft), you'll crash and maybe die but not because the rotor will stop turning.


                            --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                            --- Defend what you say with arguments, not by imposing your credentials ---

                            Comment


                            • #15
                              Originally posted by Gabriel View Post
                              AFAIK, in modern helicopters the speed of the rotor is controlled by a governol or similar that will automatically reduce the pitch if the speed descends below the "setpoint". More or less similar to the constant-speed, variable-pitch proppellers in airplanes.
                              Is it possible for this safety net to malfunction, or (accidentally) disabled? Also, is it possible for this to work wrong way round, so it stops the rotor blades? Similar to reverse pitch on a prop plane.
                              Please visit my website! http://www.schipholspotter.com/

                              Don't make me use uppercase...

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