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-   -   Very weird 206 crash video Langley BC 20 May 2021 (https://www.pprune.org/rotorheads/640612-very-weird-206-crash-video-langley-bc-20-may-2021-a.html)

lelebebbel 23rd May 2021 06:37

Very weird 206 crash video Langley BC 20 May 2021
 

Is this some crazy visual illusion, or is that thing spinning clockwise? The video doesn't appear to be reversed or mirrored, the tail rotor is on the correct side, the leading edges seem to point counter clockwise as they should. Any theories what is going on here? Media says this happened "after undergoing maintenance".

megan 23rd May 2021 06:53

Camera frame rate, a tutorial.


MichiScholz 23rd May 2021 07:55

hello,

it is impossible to start a turbine in the wrong direction even if it would be possible the free whelling unit behind wont drive your gearbox. The picture fom highrpm shows the debris from the impact spreading away in the correct direction. So this is just an ilusion.

Agile 23rd May 2021 08:40

Take off like a brute, and instantly overpitch it. Great job!

[email protected] 23rd May 2021 09:21

If that was 'post-maintenance' then don't let them service your helicopter...........

SARWannabe 23rd May 2021 09:40


Originally Posted by MichiScholz (Post 11049542)
hello,

it is impossible to start a turbine in the wrong direction even if it would be possible the free whelling unit behind wont drive your gearbox. The picture fom highrpm shows the debris from the impact spreading away in the correct direction. So this is just an ilusion.

Very true the frame rate makes it look compelling, but it is just that.

alicopter 23rd May 2021 09:43

Check weight and balance hover? Fire extinguisher in proximity? Well done the guy under the 500, quick thinking and abnegation of his own security to go and help. Respect.

SASless 23rd May 2021 11:56

Take Off to Landing...constitutes one flight.

How does the guy log the time for this one?

If he cannot log any flight time....does it count as an Accident or Incident?:ouch:

Akrapovic 23rd May 2021 12:02


Originally Posted by SASless (Post 11049683)
Take Off to Landing...constitutes one flight.

How does the guy log the time for this one?

If he cannot log any flight time....does it count as an Accident or Incident?:ouch:

Logging it as P i/c would be a bit cheeky. . .

exTabber 23rd May 2021 12:04

To be fair, he did walk away from it so does it count as a good landing?

gulliBell 23rd May 2021 12:16

According to the owner of the helicopter, I suspect not.

malabo 23rd May 2021 15:24

PIC assumes a pilot, looks more like a couple of kids that learned on an iPad sim app.

Someone with sharper eyes than mine may be able to pick up more detail. Registration isn’t current.

https://cimg4.ibsrv.net/gimg/pprune....f262f3610.jpeg
https://cimg5.ibsrv.net/gimg/pprune....4b09ca088.jpeg

Fareastdriver 23rd May 2021 15:30

How about attaching the tail rotor blades the wrong way around. The would cause them to go into overpitch which would overcome the pilot.

Not new. The first Puma that came out of centralised service at Odiham came out with the main rotor blades mounted the same as the Wessex.

I know because I was going to do the air test..

SASless 23rd May 2021 15:39

I have seen an Alouette III that flew fine with the Tail Rotor Blades on in reverse.....would have been signed off after the Air Test until a sharp eyed individual noted that minor discrepancy

Mr. Murphy must have immigrated to France where he took up Helicopter Design Engineering.

For the record I was engaged in winning a round of Uckers while that was happening.

hoss183 23rd May 2021 15:41


Originally Posted by highrpm (Post 11049522)
Looks very clockwise to me, and looks like the trailing edge is leading the leading edge.

If it's clockwise, why is the debris plume moving in the anti-clockwise direction from impact of the blade?

lelebebbel 23rd May 2021 16:14

I think that screenshot solves it. The transmission is moving to the right, as it should with the blade at the top of the frame having just hit the ground in the normal counterclockwise direction. Well then, maybe someone just rolled it up to 100% with the collective halfway up or something.​​

Ascend Charlie 23rd May 2021 19:26

Almost looks like something had snagged the front of the skid and tripped it.

etudiant 23rd May 2021 22:51

Is there a good reason for helicopters to shift to forward flight immediately on takeoff rather than to ascend vertically for a few hundred feet before heading out?
Iirc, some recent accidents might have been avoided that way.

Ascend Charlie 23rd May 2021 23:43


Originally Posted by etudiant (Post 11050011)
Is there a good reason for helicopters to shift to forward flight immediately on takeoff rather than to ascend vertically for a few hundred feet before heading out?
Iirc, some recent accidents might have been avoided that way.

Ummm... yes... it needs a heck of a lot more power to climb vertically, and it puts you into the Avoid area of the Height/Velocity curve.

tdracer 24th May 2021 01:19


Originally Posted by etudiant (Post 11050011)
Is there a good reason for helicopters to shift to forward flight immediately on takeoff rather than to ascend vertically for a few hundred feet before heading out?
Iirc, some recent accidents might have been avoided that way.

Forward speed increases lift - just like on a fixed wing. It's just not as critical on a helo.

etudiant 24th May 2021 01:21


Originally Posted by Ascend Charlie (Post 11050032)
Ummm... yes... it needs a heck of a lot more power to climb vertically, and it puts you into the Avoid area of the Height/Velocity curve.

So going vertical is more expensive (fuel and engine stress), plus it puts one into a dead mans space, too high to land in one piece and too low to autorotate. Got it, trades one set of risks for another.

Ascend Charlie 24th May 2021 05:13

Not just "more expensive", because in many cases, the aircraft has power for an In Ground Effect (IGE) hover and transition to forward flight, but not enough for Out of Ground Effect.(OGE) or OMG.

Sloppy Link 24th May 2021 06:40

It would count as a flight “from the moment the rotors start to move for the purpose of flight to the moment they stop”
Took off with HYD deselected? From my memory, apart from the position of the switch that isn’t 8n your immediate sight line, there is no other indication that HYD is selected or not until you lift into the hover and realise you need more effort than you expected with the resultant over controlling.

Only a guess.

Jetstream67 24th May 2021 07:48


Originally Posted by Akrapovic (Post 11049689)
Logging it as P i/c would be a bit cheeky. . .

Pilot in Command : “No”

Ascend Charlie 24th May 2021 09:54

If the HYD was off, the pilot would feel the feedback in the cyclic and the hugely increased effort in raising the collective - I doubt that anybody with a milligram of brains could try to yank it into the air without realising that the hydraulics were off.

OldLurker 24th May 2021 11:41


Originally Posted by SASless (Post 11049683)
Take Off to Landing...constitutes one flight.
How does the guy log the time for this one?
If he cannot log any flight time....does it count as an Accident or Incident?:ouch:

If he can log the time ... is there a record for shortest logged flight? This one looks like less than 10 seconds.

Hughes500 24th May 2021 12:10

Ascend, you are assuming everyone has common sense there ( if sense was common then everyone would have it ) I have seen quite recently a pilot get in a 206 on my home airfield and start his 206 up with the rear tie down still done up ! So I wouldn't put it past anyone to take off with hydraulics off

gulliBell 24th May 2021 13:13

I'm going to cut the guy some slack on the basis that no qualified pilot could accidently wreck a serviceable helicopter in the way we saw that helicopter wrecked in that video. There must have been something seriously whacky with that helicopter which was outside the competency of any pilot to do something to change the outcome. For the life of me I can't think what that might be, other than the passenger yanked on the flight controls unexpectedly.

JohnDixson 24th May 2021 16:43

Media reported:"after undergoing maintenance", in an earlier post. One would think that the ground run part would include trying small control movements and looking for the correct rotor response ( assume one can move the pedals on this model before starting the engine and confirming that control input is free and properly phased. Then, before getting energetic about getting up and away, lift it to just skids beginning to break ground and again, small control inputs, after which a very slow lift to a low hover and repeat the control inputs etc. Not what the video shows, but then again, perhaps something went amiss as they were just slowly lifting and the result was beyond their ability to perform any corrective action. Test flights following maintenance have to be treated very carefully.

PEASACAKE 24th May 2021 17:00


Originally Posted by Hughes500 (Post 11050374)
Ascend, you are assuming everyone has common sense there ( if sense was common then everyone would have it ) I have seen quite recently a pilot get in a 206 on my home airfield and start his 206 up with the rear tie down still done up ! So I wouldn't put it past anyone to take off with hydraulics off

Seen it done numerous times. Seen one start up with the blade tied down and intake and engine blanks in until somebody ran up and told him to stop cranking.

I personally partially blame mobile phones for a lot of it, too distracting.

FH1100 Pilot 24th May 2021 22:38

"Passenger?" Hmm.

krypton_john 25th May 2021 05:00


Originally Posted by lelebebbel (Post 11049501)
https://www.youtube.com/watch?v=mTyJV8czKBU

Is this some crazy visual illusion, or is that thing spinning clockwise? The video doesn't appear to be reversed or mirrored, the tail rotor is on the correct side, the leading edges seem to point counter clockwise as they should. Any theories what is going on here? Media says this happened "after undergoing maintenance".

Was Hogg at the controls again?

havick 25th May 2021 07:28


Originally Posted by krypton_john (Post 11050888)
Was Hogg at the controls again?

^^^^^ This post for the win.

Michael Gee 25th May 2021 08:01

Was this Heli fitted with Duels - if so had 'co pilot' - pax anything to do with what happened ? Big bag on knee etc.
Maybe that's where the reason lies.

Max Contingency 25th May 2021 08:26


Was this Heli fitted with Duels
I am led to understand that duelling in the cockpit has largely been eliminated since the advent of compulsory CRM training.

Ascend Charlie 25th May 2021 10:36

"Guns or knives, Butch?"

[email protected] 25th May 2021 11:14

Never bring a knife to a gun fight:)

Devil 49 25th May 2021 14:24


Originally Posted by JohnDixson (Post 11050537)
Media reported:"after undergoing maintenance", in an earlier post. One would think that the ground run part would include trying small control movements and looking for the correct rotor response ( assume one can move the pedals on this model before starting the engine and confirming that control input is free and properly phased. Then, before getting energetic about getting up and away, lift it to just skids beginning to break ground and again, small control inputs, after which a very slow lift to a low hover and repeat the control inputs etc. Not what the video shows, but then again, perhaps something went amiss as they were just slowly lifting and the result was beyond their ability to perform any corrective action. Test flights following maintenance have to be treated very carefully.

I haven't flown a 206 for a quarter century, but I have a few thousand hours in'em, thousands of starts and tens of thousands of takeoffs.
reflight! Preflight! Preflight!. If it's coming out of maintenance review the record and talk to those who did the work.
Part of the (my?) cockpit set up prestart checklist is run the controls through as much of their range as you can, watch the rotors change position appropriately.
The 206 cockpit is narrow, so one can't really 'wipe' the cockpit with the cyclic, but you can check for full and free movement of the pedals and collective. Full right pedal, open the door and lean out to look at the T/R blades for appropriate pitch.
The normal post start included checking that one could isolate the hydraulic system from the pump and the change in control effort is obvious. I can't remember if the controls moved to their trim position in the 206, but one would move them to assure that you could.
A guess as to why this aircraft crashed? A yank and bank gone wrong?

gator2 25th May 2021 15:29

sure looks to me like the left skid toe catches something as they start up. If you play it slow I believe i see the skid deforming a bit down at the same time the ascent is suddenly arrested.

Dave B 25th May 2021 16:40

Probably not relevant but I seem to remember from my years ago on 206s, that it is possible to fit the main gearbox support links the wrong way round, as they are handed, and this can affect the handling when collective is pulled. It is however a memory from way back.
We also had a pilot who complained that the aircraft took off as he rolled the throttle up, so one of our engineers went out and took the collective clamp off and put the lever down.


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