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John Eacott
14th Mar 2017, 00:40
Some footage of a Police helicopter possibly tangling with powerlines yesterday, with a resulting fatal crash:

X_KH1py1v8I

Evil Twin
14th Mar 2017, 01:09
Thats quite confronting footage. RIP

Agile
14th Mar 2017, 01:31
wow... always interesting to analyze accident footage, but not this one

SASless
14th Mar 2017, 01:55
Wires will straight up kill you!

Vertical Freedom
14th Mar 2017, 02:01
Disturbing footage.........Rest in Peace Brothers

underfire
14th Mar 2017, 03:35
Looking at the video, the helo failure was not due to wire strike....the tail rotor failed. From the beginning of the video, the tail rotor has failed...In no time does the helo come anywhere near the wires...

https://youtu.be/X_KH1py1v8I

John Eacott
14th Mar 2017, 03:44
Looking at the video, the helo failure was not due to wire strike....the tail rotor failed. From the beginning of the video, the tail rotor has failed...

Maybe, maybe not. Frame rate of the video may have been closer to the T/R speed which may have affected what we see as opposed to what was happening. There is a definite puff of smoke at 25 seconds and the disintegration of the helicopter starts from 30 seconds; probably co-incidental that the video is shooting through the powerlines at that moment.

Hughes500
14th Mar 2017, 07:14
That is horrible, it does look like a TR gearbox failure, think the puff of smoke is the tr box exploding as the entire hub and blades comes off
RIP guys

Phoinix
14th Mar 2017, 07:29
Is it just me or does the helicopter lean sideways on the wire in 0:22?

SuperF
14th Mar 2017, 08:06
this could have been a wire strike. lots of main transmission lines, or whatever your country calls them, have the power lines which are quite big and relatively easy to see (relatively easy, compared to an earth line, because even those big powerlines can disappear...). They can also have an earth line above the powerlines. Those earth lines are far smaller than powerlines, and harder to see, and are above the powerlines.

If you are inexperienced or distracted, you may see the powerlines and focus on them, but then run into the earth line.

and i think that you will find the tail rotor not turning is matching frame rates, etc.

SilsoeSid
14th Mar 2017, 10:01
Playing it back on a 27' screen with the sound medium, at 22secs you can hear a metallic scraping noise and can see the thin earth line lower with the aircraft, as if it has been struck.
Just before the noise, there is a puff of smoke from just in front of the trgb.

The earth line is very hard to see on a smaller screen, but you have the double line at the bottom of this screenshot, two singles above that and then the near invisible earth line caught somewhere on the ac.

http://i52.photobucket.com/albums/g11/silsoesid/mexico_zpshow9hleq.png


Looks to me, and is just my opinion based on what I see and I appreciate others view will be different, as if the ac is crossing the wires at an angle in the descent and caught the tail/trgb on the earth wire.


RiP
:(

aa777888
14th Mar 2017, 12:11
FWIW, my immediate reaction was that it was a tail rotor strike, and in the ensuing loss of control the helicopter went up above the power lines, then back down through the power lines again destroying the main rotor blades.

vaqueroaero
14th Mar 2017, 12:45
I have to agree with SilsoeSid on that one.

A sobering accident indeed. RIP.

Hughes500
14th Mar 2017, 20:26
What is shocking is to see the tail rotor assy come off, the P2 door open then the blades cut the tailboom off. Any thoughts on why the blades cut boom off unless boom fails and goes up into blades ?

rmiller4292
14th Mar 2017, 21:26
I don't think the tailboom failed, more likely a large cyclic input in an attempt to achieve forward flight and slow the rotation of the fuselage.

army_av8r
15th Mar 2017, 01:08
It appears to me that the TRGB did hit the top line. There is a rather loud metal on metal noise that occurs at the same time. As the tail rotor fails, the aircraft begins to rotate right and pitch nose down. My speculation is that the pilot may have rolled engine to idle and was attempting to start a descent, but hadn't lowered the collective fully yet. As rotor RPM drooped, they applied after cyclic to bring the nose level but with decreasing RPM the blades flapped down into the tailboom. Things happen fast, stay safe out there.

Reefdog
15th Mar 2017, 03:39
Definitely hit the earth wire.
I can relate to what is seen on the footage exactly what I did when I had a wire strike in a H-300 C, years ago
Hit wire with T/R, instinctively pull collective to get away from threat, lost T/R, around in circles I went, chop throttle, on ground, smashed it self to pieces.LIVED
The tail boom looks to have hit the main wires and drag up into the rotors
Bloody terrible sight.

Three Lima Charlie
15th Mar 2017, 14:05
This fatal accident occurred yesterday in Indiana. H-500 power line construction.

Pilot dies in helicopter crash in White County (http://www.jconline.com/story/news/local/indiana/2017/03/14/pilot-dies-helicopter-crash-white-county/99182276/)

noooby
15th Mar 2017, 21:11
Question after seeing that horrific footage....

If the earth wire hadn't been there, do you think the crew had seen the main wires? They seem to be descending at a rate that would have put them into the main conductors mere seconds after they had contacted the earth wire.

It seems like they didn't know they were on top of the main conductors at all.

Very sad. RIP to the crew.

army_av8r
16th Mar 2017, 05:59
https://youtu.be/RIZb838Um4M

RIZb838Um4M

much more detailed photos of the accident sequence, not a whole lot more that could have been done after the initial tangle with the wire.

tartare
16th Mar 2017, 06:08
Well that's pretty conclusive.
How terrible.

SilsoeSid
16th Mar 2017, 09:18
To learn from this ...

... I'm not sure if it is something generally taught or even talked about, but something I was told very early on; always cross wires at a pylon.

Of course in this incident they may not have seen the power lines or pylons. In the vid linked to below, from 1:00 the Director of Firemen tells us that it was the third time they had flown that route.
Four dead in helicopter crash near Mt. Signal - KYMA (http://www.kyma.com/news/four-dead-in-helicopter-crash-near-mt-signal/395741570)

Thracian
16th Mar 2017, 12:02
... I'm not sure if it is something generally taught or even talked about, but something I was told very early on; always cross wires at a pylon.

Thatīs what my FI taught to me also.


But there may be situations or sites when/where you cannot stick to this general rule...


Thracian

16th Mar 2017, 12:41
Then in those cases you should keep well away from the wires. In this case the weather seemed fine and there seems no reason to descend into the wires. Very sad.

Thud_and_Blunder
16th Mar 2017, 13:36
Can't always do that, Crab - some jobs involve being close to other, lower powerlines then crossing taller ones.

Our rule is to identify the limit of exploitation toward the higher line, stop, climb and cross the higher lines when in level or climbing flight (not always at a pylon, but with both crew confirming we're above the highest point of the 'threat' line) then when tail confirmed clear descend and resume work on the lower powerline.

evil7
16th Mar 2017, 16:38
Having done some flying in similar environment I guess they weren't aware of the wires and - because they were looking out of (not like the Video into!!) the blue sky they didn't see the wires over the brown ground. Sad accident😳

vaqueroaero
16th Mar 2017, 17:40
As an ag pilot I deal with wires all the time. About 95% of the fields that I spray have wires either running through them, or are bordered on one or more sides by them.
Although people don't believe it, I have found that it is incredibly easy to simply 'forget' that the wires are there, even though I have crossed them countless times whilst spraying a field. When they blend in with the background it makes it even harder to deal with. The fact that they were on their third run leads me to believe that they may have simply forgot the wires were there, or they were looking at the main wires and forgot about the static line, as I have done on many occasions.

There but for grace of God go I.......a very sobering accident as we are getting ready to start our season in a week or so.

16th Mar 2017, 19:04
Thud - very valid if your job is to work the power lines but these guys were on the way back from a rescue in what looks like good weather - they should have just given the wires a wide berth or crossed them at a pylon - basics really.

DOUBLE BOGEY
16th Mar 2017, 19:39
Or maybe cruised at a height that would allow them to chill out. MSA on a good VFR day is a stress free decision.

malabo
17th Mar 2017, 00:24
not a whole lot more that could have been done after the initial tangle with the wire.

Are you a pilot? Throttle off to stop the yaw, collective down and autorotate to the ground. Like Moffatt did in Hong Kong harbor with the 139. Why you train emergencies.

army_av8r
17th Mar 2017, 01:47
Malabo, Yes I am a pilot with almost 5,000 hours, with a vast majority in very low altitude flight profiles/ wire environments. If you watch the video I linked, it is clear that after the ground wire was severed by the tail rotor, it then wrapped around TRGB, and caused the loss of the tail rotor assembly. The cable then remained attached to the tailboom. once the aircraft began to spin it caused the main rotor and cable to entangle which caused the failure of the main rotor and loss of control. after getting the tail wrapped, its my personal opinion that recovery may have been difficult or impossible. obviously keep fighting till the end, but unfortunately this may have unavoidable after contact and entanglement.

megan
17th Mar 2017, 02:24
Like Moffatt did in Hong Kong harboOff thread. Where is young Richard these days malabo?

malabo
17th Mar 2017, 03:47
Off thread. Where is young Richard these days malabo?

Brunei Shell

DOUBLE BOGEY
17th Mar 2017, 05:46
Malabo.....are you a pilot. The procedure you describe would be somewhat ineffective at low speed a few hundred feet from the ground which where they were when the TR depart eventually departed.

Ricktye
17th Mar 2017, 13:27
Are you a pilot? Throttle off to stop the yaw, collective down and autorotate to the ground. Like Moffatt did in Hong Kong harbor with the 139. Why you train emergencies.
Have you forgotten the drastic C of G change when the T/R and GB departed the ship? He had a lot more to worry about than simple yaw!

Fareastdriver
17th Mar 2017, 15:35
When the gearbox and tail rotor depart the CofG shift will cause the nose to drop. The automatic reaction of the pilot is to pull back on the cyclic to correct. The lowers the rear of the rotor disc into the canted up tailboom and general destruction follows.

Dennis Kenyon
17th Mar 2017, 22:08
Sorry M ... in spite of the advice offered by many Flight Manuals, establishing a simple autorotation following T/R failure WILL NOT produce a safe touch down. Yes ... a first vital action is to get rid of the cause of the yaw - the engine - but if no further action is taken the airframe commences a yaw in the direction of the main blades and it doesn't matter much if you strike the ground spinning left or right, the impact will hurt. Unhappily or happily, I've experienced three T/R failures and managed a non-damaging run-on landing on each occasion ... an experience that at least taught me something. For a non-damaging landing on the more popular types, a combination of speed, yaw angle and power needs to be used, an emergency exercise I teach to my new pilots when asked. Safe flying to all please. DRK.

fijdor
17th Mar 2017, 23:34
I have to agree with D.Kenyon, mind you the situation was different from the video, didn't loose anything but simply stop working. My reaction was to pick up speed right away, i had speed to start with, just got some more and the aircraft straightened itsel or just about and went back to the airport for a successful running landing. Lucky me it was winter and the airstrip was gravel and hard pack snow. Took a while before stopping but it did before the ditch.
Aircraft was a FH1100.

JD