Schweizer Helicopter Mishap @ A.I.M.- May 2008
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- เผยแพร่เมื่อ 7 ก.ย. 2013
- Schweizer mishap @ Aviation Institute of Maintenance in May 2008 at Brisco Field in Lawrenceville, GA. This wasn't a catastrophic crash, but was exhiliarating none the less. All this thing would've done to cause possibly serious injury to somebody was for it to roll over on it's side and throw the blades, which weren't far from hitting the ground.
This is ground resonance, and it happened because the oleo dampers were removed and replaced with rigid braces (probably temporarily for servicing the oleos). I say this with 100% certainty because you can actually see them plain as day on the skids if you know what you're looking at, and this is what happens when you do that. It is not allowed to be flown like this, and shouldn't even even be run up, and here we see why. In fact, at the very least it should be marked as not for flight/remove before flight. Without the dampers, any little jolt through the airframe can send the blades off balance (for those who don't know, they lead and lag individually), and the oscillations build once they start. The ONLY remedy (and what he should have done) is to actually lift off without hesitation so that the blades can rebalance... and hope it doesn't start up again on set-down and shutdown. This was totally unnecessary, and I wonder if there is an actual pilot among them.
fatqcockandballs Excellent Explanation,I saw the Ground Resonance start as soon as he lower the collective,He should keep the pitch slightly positive until shut down
Hahaha @fatqcockandballs. Thanks for that authoritative explanation. I thought it was lucky the Hughes collapsed in that manner as it's a lot more stable splayed out on the tarmac. Just shows how quickly something can get out of hand.
Not being a pilot, (except from armchair) can the oscillation be triggered by poor control inputs, like the collective or throttle? I was looking to see if he backed off.
Shame too to wreck a lovely machine, as it didn't seem to need quite as much work to get airworthy in the minutes before the chap got in compared with when he got out.
very interesting- thanks
Very interesting, thanks for the information. It looks as if this copter just vibrated itself to death. I would have crapped my pants.
You saw the helicopter peeing itself just before...
Flight Crew: Should we tell him that the oil is leaking out?! No, Let him find out for himself, He's a big boy.
7:40 😒
Did anyone else notice that after the copter had crashed and the blade is spinning around all the people who walked toward it...wow, not the place you want to be at that moment.
I did, I left a comment about it. Seems like a stupid thing to do...
evidently they didn't hear about 'Twilight Zone' the movie.
AMEN! I was an EMT years ago and the first rule was you want to help, but no rescuers die. The person(s) may or not survive, but adding rescuers to the death/ injury toll will not help.
I didn’t see the pilot belted in !?
I noticed the guy flying the thing was at least smart enough to not get out until the blades completely stopped. If he had that might have been just enough to tip the thing over.
Wow, it really smoothed out and traveled nicely once the pilot added more forklift. Stupid ground resonance. Thanks for sharing. ✅
This old Hughes 269 went into ground resonance, because the oleo dampening struts on the landing gear look to be replaced by some solid bar links, in an attempt to get in a ground run up. This was a BIG mistake, since the oleo struts are supposed to be installed in order to absorb shock forces from ground/skid contact, so that these shock forces are prevented from being transmitted up to the rotor system, and thus knocking the blades out of phase this each other about the lead/lag hinges.
This was a great demonstration of ground resonance, and it is VERY fortunate nobody got hurt in the process!
Exactly!
I'm rather amazed at this video, being someone who is into anything with engines, I would have never continued seeing oil leaking that bad.
Does the pilot have a safety belt?
Well before that the whole damn thing was shaking. If he knew anything about anything he'd have shut it down and take it back to the garage for a full teardown.
The guy's clearly not a mechanic. I think it should be required to be a helicopter pilot.
@@nevinkuser9892the leak had nothing to do with what happened. But it certainly was another sign of bad maintenance.
@@andyharpist2938there are 4 pt harnesses in these helicopters.
You should have a sitcom. Yours would be one of the great ones. Good luck and keep em coming.
I agree with paul, being both a helicopter pilot and a crane operator, at least 3-4 people stood around for several min. Seeing this oil leak and not one person even tried to get his attention and tail him to shut it down.. this to me is an inherent safety issue, in the crane world anyone see anything that doesn’t look right is able to shut the whole operation down, this speaks poorly for all the on- lookers involved.
I have viewed this video a couple of times and just noticed something that caused this to happen. I have many years as an A&P mechanic maintaining and rebuilding this model of helicopter. If you look close there are no landing gear shocks (struts) on the landing gear. They just put solid pieces of metal on the landing gear which is a big mistake. They put (shock absorbers) on for a reason and that is to prevent ground resonance. Clearly someone used bad judgment when they decided to "run" the helicopter up without the proper parts installed.
What part failed ? Drive shaft u-joint ?
@@flyonbyya Nothing failed, the helicopter went into ground resonance, "that's when the main rotor blades moved out of there track and caused the helicopter to vibrate and start destroying itself". If the out of "phase" rotation on the main rotor blades continues the helicopter will break many things until the main rotor blades rotation stops.
@@jamescox9859 ✌️👁️👁️👍
This is what happened to an identical helicopter at my local airport but no one witnessed it. The pilot was "shook" so badly that his kidneys quit functioning for a time. I've always wondered about his incident, now I know what happened. That is amazing.
Dang
What you mean is, he pissed himself?
@Imperfect Cell That happens to me whenever I hit a bum note on my Hammond.
The thing looked like a piece of junk to begin with - parts missing, bent left skid tube. Ground crew should have shut him down over that oil leak.
My father was a ww2 vet he said only fly in a chopper if its saving your life, he also said props on choppers and planes were there to keep the pilots cool as well because he said they brokeout into a terrible sweat if they stopped turning
One hell of a good camera man, awful close to spinning blades of death with no regard for ur own safety. Nicely done!
Hey thanks! I love freelance videography, and I had to get the shot, LoL.
many can fly a helicopter....but not many can make it piss and walk away sideways.......nice work sir.........
😂🤣😆🤪
Nice Work ..................BULLSHIT! CRASH?
You have to tighten your nuts. This is why the caps came loose and you were pissing brake fluid all over and this caused your slippy's to get all wet and Looby and slap you around like a Drunken Fish. Probably shouldn't get drunk next time just smoke some weed Maybe or some cocaine for courage because you looked pretty scared and I also noticed that you pooped your pants that is why you wouldn't get out because your friends would all see your poo stain and smell it and point and laugh. If this happens again pin the throttle to level out the rotational circumference and Gyro that shitt around for a couple laps like nothing happened then maybe lands down the street and try running 40 to 1 ratio because you obviously fouled a plug.
Like a boss. 😁
🤣😭😂🤣
I trained in the TH-55. There were no crashes due to maintenance problems while I was there. The Army had a contract maintenance and it was top notch.
Then again, i have never seen a bird with wings on top of his head, or an airshow of vintage helicopters!
I know this video has been around for a while, and I’ve seen it before, but I heard something this time that I hadn’t heard in the past. That was the pilot telling the others to back away until the blades stop spinning. Good lookin out on his part.
You meant giant food mixer just on top of his head ?
Bad stuff happens anytime there's a ponytail dude involved.
Kowboy USA I agree
When it started dancing and coming apart, I dove behind my T.V! 📺🤸♂️
Kowboy, You look like one yourself.
Yeah ponytail and those baggy pants tell the story.
Only if the ponytail has highlights.
4:08 when the old guys are hiding behind boxes, you know they know something is going to happen.
got that right ahahah
Yeah, because as a pilot, that's exactly what you expect of your mechanics... To be cowering behind crates. Happens all the time
That's how they got to be old guys!
And to be honest If I was there I'd be hiding behind something solid too, NOT filming it without a _very_ long lens.
Like Marlin Perkins hiding in the bushes.
Ground resonance. 1. wrong blade dampers, should have the elastomeric ones. 2. Blades out of track / balance. 3. and worst of ALL NO DAMPERS ON THE LANDING GEAR. the engine had nothing to do with it. The solid struts instead of dampers on the landing gear made this a done deal as soon as he engaged the blades. Expert opinion - YES. I was one of those that built that Helicopter. The landing gear dampers are there for a reason.
the vibration from out of balance and out of track were so obvious at 3:24 to 3:42 (the close up) you could see his pectorals and whole body shaking.he should have shut it down shortly after engaging the rotor,not lift the collective! that's what stubbornness buys.
Yes you could clearly see the vibration, but without the landing gear dampers, He NEVER should have turned the blades at all.
yep.he shouldn't pilot a fling wing ever again.
completely agree with all of above. it also looked like 'pilot' never had shoulder straps, wonder if he had a lap belt on.
David, is there an equation to calculate when ground resonance will take place? I.e., rotor length vs length of aircraft or landing gear? I'm in aviation technology school (as well as math major) and am thinking of writing a paper on ground resonance
" Hey mister, you have a leak "....05:48....." No thanks, already took one".
“I’m all shook up, hein hein hein...”.
A rather strange sentence from the description section: "This wasn't a catastrophic crash, but was exhiliarating none the less".
Praveen b LMAO wow
Put together and flown by Fairground Technicians who have just done a short course in the "Moving Teacups".
The Oleos (shock absorbers) were replaced with solid shafts on the landing gear. 100% reason this happened. All semi and fully articulated rotor systems have to have shock absorbing landing gear or this will definitely happen. If he pulled collective the helicopter would have come off of the ground and the ground resonance would have stopped, but it still would have been tricky to get back on the ground without the same result..
That is literally what my brain came up with too. Ha, I agree...
Looks like a Rigid blade system though
These guys made a completely illegal modification to the aircraft and it's exactly what caused this as Kurt said. Also,the pilot has had VERY poor training. One of the first things drilled into me when I transitioned to this same type of aircraft was to PULL COLLECTIVE!
Holy crap I didn't notice that first time around and I used to fly these. Cowboys for sure. The old style dampers too, not a torque wrench in sight.
Back on autorotation?
HAAAaaa! I've been a News cameraman all my life and lifted a Hawker Harrier off the ground at Oshkosh! This footage and capture was fantastic. Cut off all the other excess, use notes, either your voice, or text to talk about the leak, explain what's being seen and by presentation, you'll triple the views, in time. This is awesome, bro. Keep doing what you love.
Hey, thanks man!
On the bright side of things the skies are much safer now and we have properly adjusted the resell value of one slightly used helicopter
You didn't even flinch when the bird started tap dancing.
Finally a cameraman filming an actual aircraft incident without filming his feet or the wall while running
So, you are saying that he did a good job basically ?
He actually could have filmed him being beheaded, well just cut in half in every possible parts with these high velocity blades that failed to touch the ground.
Some people just fail to see the danger.
What about this camera man at 1:08 ? th-cam.com/video/pOfg0Q5mX3o/w-d-xo.html
I had ground resonance twice. Both times were on Astars. Both times I lifted off immediately and it went away as fast as it came. If you have lots of RPM its best just to lift off so it can balance itself out.
How can you tell when your blades are out of balance? By your missing teeth. 😆
Load the blades, always.
get away from that nasty ground asap.
Actually, you can see that once the oscillation gets started, the mass of the pilot's arm drives resonant inputs to the collective. This sort of thing has destroyed other helicopters - the Cheyenne program lost a prototype to it. It's not really a PIO, because PIO generally involves unskilled inputs - here it's just the fact that the mass of the arm is attached to the collective. One of the comments below mentioned "shock struts" - would this component have provided the required damping? Anyway, very interesting, thanks for posting!
Many years later, probably not? Sitting on the ground should have fully compressed the struts. They're meant to absorb energy from landings to prevent a "jolt" from being transferred to the rotor head and then back to the ground.
I'm watching this on a massive screen. His hand dropped the collective as soon he felt it, which brings the question: Why was he pulling the collective at all if he had no intention of flying?
I've seen at least one ground run on a Cabri G2 where I think the pilot's grip on the cyclic may have coupled an oscillation. Because it didn't get worse after it was fully developed and the oscillation was perfectly in sync with the pilot being wobbled side-to-side.
I've been there where the love of flying blinds one to the lack of funds for maintenance.
I hope none of these guys made it out of school. To stand and watch an airctraft run with an obvious fault and do nothing but laugh when shit hits the fan......... I would not trust any of them with a bicycle
YOU got that RIGHT Slick!
That’s what friends are for!
I wouldn't trust anyone wearing JNCO's to tie my shoes, let alone touch an aircraft.
…you'd run towards the spinning rotors…? to do what with your bare hands?
They don't even bother to fix their shitty-running forklift from the way it was revving up and he had to ride the clutch. A motley crew indeed.
The oleo struts are missing. BTW, the early AS 350 had a ground resonance problem as well. They're all good now though.
Hardly the fault of the cameraman with all of those mechanics looking-on. I do not claim to be an expert on the Schweizer, but I DO have about 85 hours in them as this was the Primary Trainer in the US Army when I went through Flight School in the mid-to-late 1970's. But they taught us that helicopters with oleo struts on the undercarriage are susceptible to this phenomena called "ground resonance" and there are many accounts of this phenomena yielding far more catastrophic results than what we see in this video. Apparently the guy at the flight controls managed to take the appropriate action in order to stop it but it had already evolved beyond the point of being able to prevent any damage...and you can hardly fault him for that as you can see that catastrophe can manifest itself in milliseconds. It is difficult for me to tell if the leak even had anything to do with what resulted here unless it had ultimately caused the engine to run rough enough to create a low frequency vibration which may have been capable of inducing ground resonance while the aircraft may have been light on the skids, but I won't speculate on that because it didn't appear to me that it was light on the skids in that moment either. Just a bad day, but the good news is that nobody was hurt in the process of things falling apart, which some would rationalize is a small miracle in and of itself.
Larry Curtis s
? LOL ok. Not totally sure what you meant by that but thanks. ;)
Excellent explanation. Thank you
Thanks 4 this video
No prob!
wow. i dont wanna be a helicopter when i grow up anymore
i still identify as one
+Matt Lifts apache attack helicopter
SnarkieVlogs I am a helicopter
My friend was a helicopter, but he was cured.
SnarkieVlogs hahaha
I was an instructor there and am actually in this video, lol. This helicopter was donated to the A and P school. The struts were removed, the chopper didn t run, and it needed quite a bit of work when it arrived. The guy in the cockpit had thousands of flight hours in helicopters including hundreds in that airframe. He was a great guy and mechanic but shit happens. After this happened he put the chopper back together and wanted to run it again. Our supervision did not let him while I was still there.
Accidents don't "just happen".
The shock absorbers were removed from the landing gear.
Had one of these helicopters at my school. If I recall we were strictly prohibited from flying anything there due to legal reasons. We used to do ground run ups like this on it for the students but always kept the blades disengaged for this exact reason.
You didn't panic but instead kept the camera on it the whole time. Rare sight, nice job.
As for this crew, irresponsible would be an understatement. Even before the leak was evident, the pilot was jiggling like a bowl of Jell-O. I know copters shake a little but this thing was an unbalanced disaster waiting to happen.
Nice job...
Sorry but is that an ironic comment ?
The cameraman continued filming, no danger at all with these spinning blades at very high speed and very high velocity just on top of the ground.
Taking risks to be beheaded much ?
Are you really serious ?
Is the cameraman good enough for you on the following link ?
th-cam.com/video/pOfg0Q5mX3o/w-d-xo.html
LoL, yeah, I was really starting to wonder what kind of school this was since they are willing to fly an un-airworthy aircraft. I just KNEW this was coming, so I had to video it. It just goes to show you how professional or not an Aviation School is just by the things they allow. I'm glad nobody was hurt, and especially since there was an open air restaurant called "The Flying Machine" only about 100 feet away from the crash site with people watching.
chopperbubba Looks like an engine test to me. Clearly it failed. And what a weakly built bit of kit, falls to pieces from a bit of vibration.
chopperbubba testing an engine without a load is not testing an eng...
Poo
More like the Aviation Institute of Retards. I love how all the guys approach the helicopter after it breaks down, and just blankly stare at it. You see the same type of behavior at mental hospitals. Hahaha!!!
. . . did they try to get it put back together (properly) and in the air, or did it become Spare Parts after this?
Thank you BEST camera person also brave operator ,nice pedestrian too.till then keep smiling with lol politely and healthy safely maintenance.
Great video!
Absolutely amazing... out of four or five people standing around on the ramp with their THUMBS up their asses, PLAINLY seeing that there was a huge oil leak going on, and not a SINGLE ONE has the sense to go let the pilot know there was an issue??? Stay the HELL away from MY aircraft!
Ya noticed that to, huh? Did ya notice also right from the beginning of the startup that the tail boom/tail was vibrating up n down?
RODNEY L.
Hahaha its normal, until RPM get high enough to stabilize the tail
Somebody go get the duct tape from the top drawer of my tool box in the hanger and we'll have this bird up in no time.
I was lookin' for Red Green. Didn't see him...
I got the beer
So many people saying its because of the oil that is leaking, no it wasn't the oil, it would have just over heated and that's it, but the vibrations on this helicopter put it into ground resonance which caused the destruction
(READ THIS IF YOU DON'T KNOW WHAT GROUND RESONANCE IS): Ground resonance is when vibrations go from the ground to the helicopter rotor blades causing the rotors to imbalance, and when it imbalances it causes more vibrations which causes the ground resonance to be more severe
The most true and pure meaning of... 'The pilot was shaken up'
Knuckle heads... Loved how his hat flew off his head on to the ramp.
Yes of course hats are not allowed on the ramp with active aircraft. Rest assured professionals do the real work
When you have ground resonance with a
300 always more collective to leave the ground as soon as possible!! but it's more easy to say then to make!
You clearly have 0 hours flying helicopters and 0 training. If you did, you would know he did not have the rotor speed.
Better for you to change business... helicopters are not for you little man , you don t know anything about me and helicopters experience , attack is very easy , try to return at school to learn a little helicopters mecanical ah ah ah
I liked the confidence of the two guys standing behind the big boxes at the beginning of the video. Or maybe that's foresight...
Hi, I would be interested to license this video. Is it generally possible to get in touch with you regarding this? Kind regards
You knew something bad was going to happen when you see he people hiding behind the boxes
the older mechanics got old by not being stupid, or ignorant. faa has laws but those can be ignored. the laws of physics cannot be broken, they break you
Please rename this video to say "Ground Resonance" rather than calling it a crash. Very useful video for instructing student pilots on how quickly Ground Resonance can develop. They need to know exactly how to correct it the second they feel the onset--in this case the pilot should have lifted up to a hover, although I don't know if it was possible in this particular 300's state of repair. Thank you for posting the video.
Well, that escalated quickly 😂
I have flown this model and it appears to be missing some keys elements especially on the landing skids. No shock absorbers that I can see on the skids? Iv'e flown quite a few hours in these and they are great chopper, especially for training on. Ground resonance is a bastard when it bites and it can happen to anyone. Glad no-one was hurt.
The shock absorbers are the only key elements missing for this accident. If the rotor dampers are functioning properly and the shock absorbers (struts) are charged to the proper level, then this will not happen.
that thing was a bag of shit and those so called mechanics need a good slapping for letting the pilot carry on and putting all those lives at risk when they could clearly see as we all could there was a serious leek
' " que gran cagada ""
leak didn't cause the accident. I could hear and see a bad vibration when he first cranked it up. Main blades may have been out of track. Yow.
***** i know enough to know a seizure when i see 1 and the effect it has on the shaft and consequently the heli
think maybe it was a test and done purposely?
lol "oil starvation".... no
This was a classic case of ground resonance.
"pulling the pole into a hover would have been a really bad idea"
Actually, pulling into a hover is what he should have done. Ground resonance only happens when in contact with the ground.
Observing structural failure of the left landing gear, and the blades still turning at deadly rpm, the "ground crew" charged up to the unstable disintegrating machine and stood under the deadly spinning blades - with only the vestiges of stability remaining by a fortunate but unlikely chance saving several people from fatal head smashing. Very scary.
Fatal RPM? It was down to about 15 RPM when the first guy went, and 6-10 when the rest joined in. Hardly fatal. 15 COULD be, but even that would be very unlikely, It would be about like getting hit by a bat.
Bruh heli blades at flight speed spin at 400(ish) knots at the blade tip. even if it was 15% thats still 60+ knots.
If those blades were 2 feet closer to the ground, the outcome would've been alot different. Glad it worked out and everyone safe.
I think it was just really happy to see everyone. what a good boy!
i flew on those helicopters in my flight training.. They are very good helicopters safety wise (once in the air) but very dangerous machines on the ground when the blades are spinning. They are extremely prone to ground resonance... ive experienced it multiple times in these.. unless the pilot reacts fast the helicopter will be a goner.
That's not true, I have never had a problem with ground resonance with over 5000 hrs in these models alone. It is only when the shocks are not properly serviced or the main rotor dampeners are not serviced prpperly.
@@jamescox9859 well I experienced it twice during that training alone (during the first 150 hours ) .
I don't fly on those helicopters since I finished my training , and I never experienced it since then .. but it does happen often on these .. but since most ppl are trained correctly in how to respond to it ,it's not a big deal in the grand scheme of things .
Blade tracking was way off. Looks like one high and two on track. Dampers were over-run when he pulled up the collective and the loads increased and the fun began. Very glad no one was hurt.
The schwiezer uses elastomeric bearings as dampers, not compressed cylinders, how could they pay a factor?
Oops your wrong: "ntsb.gov/aviationquery/brief2.aspx?ev_id=20040506X00569&ntsbno=LAX04LA197&akey=1"
"The skid damper assemblies were examined and tested for charge at a maintenance facility in the presence of the National Transportation Safety Board investigator-in-charge. The landing gear dampers are pressurized with nitrogen gas. Technicians pressurize the dampers in accordance with the current operating temperatures and environments at the time of the maintenance period. The dampers assist in absorbing the vibration consistent with helicopter operations. In post accident tests, the rear dampers had a lower charge than that specified in the maintenance manual for the helicopter. The forward dampers were within limits. The main rotor dampers were examined with no mechanical anomalies noted."
Josias Rivera
"In table B-2 of the Schweizer Handbook of Maintenance Instructions, Section 2, page 2-8, item 30 on the 100-hour inspection checklist states the following:
"Forward and aft landing gear dampers (LH [left-hand] side and RH [right-hand] side) for operation and conditions, and for damper extension with full fuel tank (Basic HMI, Section 12). Visually check dampers for leakage; replace if leakage is obvious or extension is not within limits (Basic HMI, Section 12)."
Oh haha we are talking about 2 different systems. My apologies, I thought you were referring to the main rotor system. Evident now you were talking about the skids.
Josias Rivera True but the blade lag dampening also has a limit of travel. Seeing this guy bolting the blades on leaves me with little confidence any other limits on the blade specific parameters were followed. I don't know the specifics on the 296 lead/lag settings. Obviously there has to be a max lead/lag. Seeing the rotor disk from the top would have been very helpful.
I see no N-number on the chopper -- might this be the reason why there is no NTSB report? Was it an instructional airframe?
Is ground resonance a problem with a two blade main rotor?
Looks like the thing had a friggin seizure
The proverbial accident waiting to happen. It just happened to be ground resonance, but given the attitude toward the oil leak, the incident may well have saved the pilot's life by preventing the take off with a non-flightworthy helo - who knows what else was wrong with the machine. Who are those people? Is this actually a maintenance school? Seriously?
Yeah, it is an actual maintenance school now located in Duluth Ga. I attended that school for the entire 1920 hours or 18 months. I would say that, some of the training is well presented, but in other areas, it seemed the school (which is privately owned) would not update their training aids. We had to train on equipment that was very outdated and falling apart. A lot of the equipment was so dilapidated that in many classes, like hydraulics or reciprocating engines, we couldn't fix anything because either there wasn't any good items to work on or the required tooling was broke or unattainable. I would recommend someone go to a facility like Embry Riddle before this place, which is far more professional in its training program. So, isn't it ANY wonder that this helo crashed the way it did. It was sitting in the corner of the hangar for many months before they ran it up. And there is no telling how long it was sitting before they got it.
corisco tupi
Ground resonance, where a slight imbalance between rotor, lifting forces reacting with struts on ground getting into a resonance... the cure is to lift off into hover.... it was not necessarily the maintenance condition of the aircraft, but pilot incompetence played a roll. Also the struts did not have their oleo dampers on them... removed for some reason which made the condition likely... once resonance starts the amplitude will increase quickly until their structural damage.
What this shows clearly is that the pilot essentially becomes incapacitated due to various forces. I have seen various comments over the years that fail to recognise this phenomena.
What a joke. guys standing around watching as the engine looses oil on the manifolds, and nobody tell the pilot to shut it down.
Agreed. Loser ground crew. Should have given the "chop to the throat" signal wwwaaaaaaaaaaaaaaaaaaaaaaaayyyy before the shake, rattle and (almost) roll!
Totally agree.
Yep, agreed. Total amateur hour
Well, these comments are amateur hour. Obviously they anticipated an oil leak. It’s not common to surround a helicopter with fire extinguishers. The oil leak had nothing to do with the cause of the accident. It’s called “ground resonance” and it is caused by rotor blades out of balance or bad shock absorption. Just like it said at the beginning of the video. It’s a real thing, look it up.
@@Tenere7mufd1924 Just like the military, manned fire extinguishers should be there on starts such as this. I would say you are the amateur. A leak check for fuel and oil leaks should have been one step, then if NO leaks go to the next step, engagement. No one seems to care a bad fire was very possible with oil dripping on the exhaust, everyone watching had the right to tell the pilot to chop the throttles and shut down. If they had solid braces instead of shocks then they knew nothing about helicopters dynamics even with phasing the blades before start up.
3:24 you can see by the way he's bouncing around that there's some kind of vibration going on
Never encountered ground resonance myself but I always heard that the only way to stop it is to lift off quickly
Unfortunately once it has started it is impossible to stop. You have to understand what is happening before it gets to that point or else you are too late. The problem is, it happens so fast that it is hard to "catch" it fast enough to stop it. One thought is if you feel anything that is not normal from what you have been used to while landing, then lift off. No one knows exactly what that "normal" is because either you lift off and land again or the helicopter has destroyed itself and you have been injured or shaken up badly.
YOU WOULD NEVER GET ME INTO ONE OF THESE PIECES OF JUNK NO WAY JOSE.
AS a retired fixed wing pilot, I honestly believe that anyone flying in a helicopter is either MAD, OR THEY DO NOT APPRECIATE THE RISKS INVOLVED.
You're just jealous of those of us who can keep our lifting surfaces at flight speed while the cockpit remains at zero air speed. (LOL!)
It’s not IF you’re gonna crash, it’s when.
I've been flying fixed wing for 50 years and just started taking lessons in an Robinson R22 and loving it. I'm addicted to helicopters.
Well it's a good thing nobody cares what you think.
WOW. This aircraft is flown in the right seat since the tank is on the left. The Oleos are missing and the skid was uneven from the get go! What kind of thought process makes one even start the engine up under these circumstances? Well....great job on making a candidate for a static display....hopefully that's all this guy is planning on! Just WOW!!!
Thanks for the video. Excellent example for bad ADM and the wild ride we have all experienced more less while operating fully articulated rotor systems.
Maintenance call owner afterwards: "Hay man, the thing we talked about for $5000, it's gonna be $100.000 now....are you ok with that?"
5:48 when your mom comes home and you haven't done the chores
Man I recognize some of the instructors. Glad I’m out of that school.
Got into an old helicopter and noticed some oil leaking overhead in the cabin directly below the rotor mast. I ask if that's anything to worry about and the pilot said "No, only if it stops dripping".
What? Any leaking directly below the rotor mast is cause for concern. Being a mechanic and pilot, I have heard things like this before and every time some one told me that, I checked out the rotor system and find serious problems. One time someone came to me for some flight instruction and I told them the rotor system was "shaking" to much and I was tole this was normal. Of course I told them I would not fly until it was checked out. Found all three rotor dampers were out of hydraulic fluid and the mast nut was loose. NEVER take a pilots word that nothing is wrong just because that is "normal" for him.
@@jamescox9859
Not flying wasn’t an option at the time. Lol. Auto-ing down early wasn’t option either. Better off dead. Pucker & pray.
what was the cause?
Did you think that vibration was just going to fix itself?
The cameraman didn't move a muscle like a boss
I thought at the first sign of ground resonance the pilot is supposed to get airborne immediately.
I love how the guy casually walks over and grabs the fire extinguisher before the melt down,
Helicopter shatters into bits. Catastrophically disintigrates. Bits fly off.
Five expert onlookers: "Let's move in, and stand under the rotor disc and ascertain if the blades will fly off, craft will roll over or if we can help stop any rotating parts killing anyone within 150m."
Ground Resonance ... Never seen that happen on startup...
Can somebody explain to me why the people watching didn't tell the pilot to shut the engine down immediately they saw the oil leak? They clearlyl saw the oil leak. which was a serious oil leak and the pilot either was not told about it and it did not register on the his oil pressure gauge or just ignored it thinking it would go away. Its quite amusing.....
I know right, that's what i'm saying. The thing starts dumping oil, I seen it and the guys on the ground see it. How could they not. Or did the pilot know and try shutting it down. I know nothing about real helicopters and how they operate. But yea the thing looks pretty much totaled. That would suck.
This about sums up why I walked out of AIM first semester.
Nice video keeping aim on the aircraft during this mishap. I always stay behind something.I would have powered down as soon as the smoke was seen.Can this helicopter be repaired, or is there also internal damage which is too extensive? Thank you.
"That'll buff right out." -These guys, probably.
5:55 knocked his hat clear of his head.
That thing looks like I feel on a Sunday morning after an excellent Saturday night out!!
I'm guessing that zoom in at 3:33 that shows his body shaking the rpm is exactly half what it is when it all flies apart.
It didn't want to fly, it wanted to walk!
Why continue when it's obvious there's and on-going issue when you have fluids leaking
What's that about when half the bolts are loose anyway.
Would love to read the NTSB report.
You have to pull the rotor blades back until they make a loud noise, then do the final torque adjustment otherwise the rotor may be unbalanced. I have seen this before live. The guy flying it was able to hover a bit before putting it down in the apron while everyone was ditching for cover. Then a mechanic experienced on this model came and adjusted the blades by hand. 30 minutes later it was flying smoothly. It may be it you never know right!
What? The adjustment you are talking about is done with the main rotor dampers on the bench. There is a procedure that some very experience mechanics use to "help" set the dampers but sometimes you have to replace a bad damper because it was not rebuilt right, the old plates that or worn were not replaced and some of the parts in the dampers are worn to much.
Remind me not to go to that aviation maintenance school...and hopefully not to fly in anything they wrench on!
They've gone.
Ground Resonance = calls for an immediately lift off, or else matter
or cut-off?
stealhty1: Yep, depending on the rotor RPM and the power setting: shut down or lift off but in any case you have to decide very quickly. In this video, the man with the camera was playing russian roulette, as chunck of metal were flying everywhere. Nobody was hurt. God was in good mood this day.
stealhty1 finally, someone who actually understands how to fly.
@@rolandprotoy5752 hopefully he was ducked down with just the camera up.
Just SMDH at how close so many of them were standing to an unproven rebuild. As a former helicopter mechanic, it scared the piss out of me every time I had to standby with the extinguisher while the pilots ran things up.
Centripetal force is a killer with blades having the ability to travel hundreds of feet after a ground strike.
No, it's lack of centripetal force that's a killer. Centripetal force is the force that keeps things from flying outward.
@@andrewalexander9492 It depends on the condition of the system when the force is measured. Pre failure is centripetal. Post failure is measured by the velocity at which people shit their pants.
@@ksnax No, centripetal force is a force acting toward the center of rotation. Period. That's the definition of centripetal force. The definition doesn't change depending on when you measure it. This is basic high school physics
@@andrewalexander9492 And without it, the blades would never spin.
Was there oil in the engine?
The only thing I like about rotorcraft is that they have the decency to part themselves out.
Yep. This will do it. Done scrolling and now I can move on. Ahhhhhahahahahaha!!!
Did anyone notice he was loosening with the ratchet
he is indeed ,,,,
He is Very Lucky, the first thing I noticed was that he wasn't even strapped in, not that he was going to lift off to begin with but that copter bucking like that could have thrown him out and blades in contact with heads and limbs don't fare well most times.
I remember Vic Morrow and what happened to him and those 2 kids.
It started off great as someone was tightening main rotor bolts with no torque wrench.