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Nobody was injured in this weird, weird, WEIRD helicopter accident, so you can laugh away from minute one. I feel sorry for the people getting shaken so badly, but it is hilarious.
It happened last Wednesday in Para, Brazil. I’m sure some of our readers would be able to explain why this thing started to shake so badly after landing, because I have absolutely no clue.
http://www.youtube.com/watch?v=K1Qxa031xBA
Clearly what they had on in the cockpit.
“shaken so badly”
ahaaaaaaaaaaaaa
It may be because it was a fairly flimsy helicopter that just happened to be vibrating at its resonant frequency
You’re on it! This is a phenomenon known as ground resonance; basically what happens is (generally) some moderate impact between the ground and the helicopter will set one of the blades advancing out of sync with the others (helicopters with 3+ blades and this type of “fully articulating” rotor system are vulnerable to this). When that happens, there’s a resonant vibration between the blades and the ground. An increasingly out of balance rotor system then basically shakes the whole machine apart. It would not be a fun experience! Usually this happens when a helicopter lands a bit hard, I’m not sure if that happened here. A blade dampener failure could also explain this.
Further reading: http://en.wikipedia.org/wiki/Ground_resonance
You learn something every day …than you good sir!
Ground effect combined with resonance…hope he had insurance….
My guess is the engine, the prop shaft or the connection between the 2 was slightly lose and thus gave it enough room to create a kind of gyro effect as oppose to just a rotation.
Could be miles off though of course
as is the case with aircraft and helicopters especially, even the slightest miss alignment can lead to catastrophic failure
The aircraft suffered excessive vibration while still airborne which then developed into a phenomenon known as ground resonance. Ground resonance can develope in a perfectly airworthy aircraft, it is the result of an out of balance condition, combined with reactive forces from the landing gear, as the vibration is fed in part by the gear bouncing off the ground, the solution is usually simply to engage a hover, in this case this did not happen (and may not have help as there seemed to be another issue in addition to that, I’m not really a rotor guy, so that’s about the best I can give you
It’s just like that washing machine. It appeared to shake itself to pieces in the same way. http://www.youtube.com/watch?v=6_PLnInsh7E