Helicopter crash New York City
Joined: Sep 2000
Posts: 166
Likes: 7
From: states
Utility
Not a big deal---most of those flights are only 20-30 minutes. When I flew tours in Hawaii, a standard day was 8 x 55 minute tours per aircraft, and we would do that year round. There were obviously slow days in there too.
In utility, it is not uncommon for my aircraft to fly 6 or 7 hours per day on revenue Hobbs which can equate to 3 or 4 hours on the collective Hobbs depending upon type of work. Hay-bombing it is common to see 11-12 hour flight days in summer.
In utility, it is not uncommon for my aircraft to fly 6 or 7 hours per day on revenue Hobbs which can equate to 3 or 4 hours on the collective Hobbs depending upon type of work. Hay-bombing it is common to see 11-12 hour flight days in summer.
Joined: Sep 2003
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Likes: 189
From: Redding CA, or on a fire somewhere
Shameless plug: I do have 2 positions open for “apprentice utility pilots” if anyone is US legal with 2,000 hours and wants to get into this type of work….fire & power-lines primarily…power work is all HEC in Bell 407’s or BK 117’s.
Joined: Nov 2010
Posts: 880
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From: Australia
Here is the best explanation so far---not mine BTW, I tend to agree and am merely copying it:https://www.youtube.com/watch?v=graz-V-Hksw
Turn sound on!
We have all seen this one at this point but depending on where you watched it, the media scrubbed the audio off of and talked over it. Slow it down, you will clearly hear the sound of a tail rotor drive shaft impacting the metal of the tailboom....
Turn sound on!
We have all seen this one at this point but depending on where you watched it, the media scrubbed the audio off of and talked over it. Slow it down, you will clearly hear the sound of a tail rotor drive shaft impacting the metal of the tailboom....
The caption at the start suggests the frequency of the sound heard during the lead-up to the breakup matches the rotor RPM. Is that really the case? In any case, it certainly reduces in frequency over time suggesting what ever it is is slowing down. I am not sure if video or audio are at 'live' speed. Not even sure the audio is from same location as where this video was taken? To me the sound seems more like a jack hammer being used in the bowels of a ship. The regular sound of a 206L can't be heard beforehand either, why? Was sound of the breakup so loud that it dominated anything else picked up by the microphone in a busy city?
Once the source of audio is validated, should be straightforward for NTSB to analyse its dominant frequency and whether that matches main rotor RPM, tail rotor RPM or tail rotor drive shaft RPM (if different) or anything else, including harmonics.
With the sound synchronisation, the "banging" is already starting before the helicopter emerges from behind the building.
Joined: Sep 2003
Posts: 2,081
Likes: 189
From: Redding CA, or on a fire somewhere
Flight hours and cycles are two almost totally Independant contributors to structural damage. The Hawaii 737 is the poster child for the importance of cycles. If cycles were an issue for tour hellos, something would have popped up by now. There is another issue involved in this accident.
Joined: Oct 2003
Posts: 221
Likes: 2
From: Hampshire, UK
Juan Browne has recently also uploaded the video but now with the audio apparently synchronised with the video (presumably by matching the fuselage striking the water with the sound of such an impact):
https://youtu.be/PFesmc48JNY?si=9srGyELlF--ml_Eg
The caption at the start suggests the frequency of the sound heard during the lead-up to the breakup matches the rotor RPM. Is that really the case? In any case, it certainly reduces in frequency over time suggesting what ever it is is slowing down. I am not sure if video or audio are at 'live' speed. Not even sure the audio is from same location as where this video was taken? To me the sound seems more like a jack hammer being used in the bowels of a ship. The regular sound of a 206L can't be heard beforehand either, why? Was sound of the breakup so loud that it dominated anything else picked up by the microphone in a busy city?
Once the source of audio is validated, should be straightforward for NTSB to analyse its dominant frequency and whether that matches main rotor RPM, tail rotor RPM or tail rotor drive shaft RPM (if different) or anything else, including harmonics.
With the sound synchronisation, the "banging" is already starting before the helicopter emerges from behind the building.
https://youtu.be/PFesmc48JNY?si=9srGyELlF--ml_Eg
The caption at the start suggests the frequency of the sound heard during the lead-up to the breakup matches the rotor RPM. Is that really the case? In any case, it certainly reduces in frequency over time suggesting what ever it is is slowing down. I am not sure if video or audio are at 'live' speed. Not even sure the audio is from same location as where this video was taken? To me the sound seems more like a jack hammer being used in the bowels of a ship. The regular sound of a 206L can't be heard beforehand either, why? Was sound of the breakup so loud that it dominated anything else picked up by the microphone in a busy city?
Once the source of audio is validated, should be straightforward for NTSB to analyse its dominant frequency and whether that matches main rotor RPM, tail rotor RPM or tail rotor drive shaft RPM (if different) or anything else, including harmonics.
With the sound synchronisation, the "banging" is already starting before the helicopter emerges from behind the building.
Joined: Apr 2025
Posts: 1
Likes: 0
From: Ireland
How would you manhandle a 206L to make the tailboom fold? Considering it appears to be in level flight and under power.
There’s rumour, then there is fantasy. With so many non aviation folks following a high interest topic, it is frankly irresponsible on a professional site (that comes ahead of the rumour in the title) to give credence to such unsubstantiated nonsense.
There’s rumour, then there is fantasy. With so many non aviation folks following a high interest topic, it is frankly irresponsible on a professional site (that comes ahead of the rumour in the title) to give credence to such unsubstantiated nonsense.
we have operated 206 Tours in the past. The machines were rigged for duel pilot operation for recurrent training, et cetera
but when operating with passengers, the copilot pedals were enabled ,has anyone asked the question about the copilot pedals position at the time of the catastrophic failure?
Joined: Feb 2007
Posts: 29
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From: Scotland
Hi guys. Just clicked into this site.
we have operated 206 Tours in the past. The machines were rigged for duel pilot operation for recurrent training, et cetera
but when operating with passengers, the copilot pedals were enabled ,has anyone asked the question about the copilot pedals position at the time of the catastrophic failure?
we have operated 206 Tours in the past. The machines were rigged for duel pilot operation for recurrent training, et cetera
but when operating with passengers, the copilot pedals were enabled ,has anyone asked the question about the copilot pedals position at the time of the catastrophic failure?
Joined: Jun 2016
Aviation Qualifications: CPL
Posts: 1,318
Likes: 386
From: Brantisvogan
Hi guys. Just clicked into this site.
we have operated 206 Tours in the past. The machines were rigged for duel pilot operation for recurrent training, et cetera
but when operating with passengers, the copilot pedals were enabled ,has anyone asked the question about the copilot pedals position at the time of the catastrophic failure?
we have operated 206 Tours in the past. The machines were rigged for duel pilot operation for recurrent training, et cetera
but when operating with passengers, the copilot pedals were enabled ,has anyone asked the question about the copilot pedals position at the time of the catastrophic failure?
It helps to scroll back and read the discussion before offering repeats.
Joined: Oct 1999
Aviation Qualifications: ATPL
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From: Den Haag
Joined: Feb 2015
Posts: 258
Likes: 58
From: USA
in any case, I have had a copilot apply full pedal at 100 kts (well, maybe 97! ), in a B212, and my tail didn’t come off. He decided to adjust his seat fore and aft, after I gave him control so I could eat my bacon roll. The floor was wet, and didn’t offer any friction, so his foot slipped with full force. Never did get to finish the roll as it ended up in the chin bubble……
Joined: Oct 1999
Aviation Qualifications: ATPL
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From: Den Haag
I don’t think so. Our 212s in the water were CFIT at night (North Sea), disorientation and loss of airspeed (North Sea), blade delaminating (Nigeria), swashplate failure (Nigeria) and another Nigerian ditching that was never established. Maybe others I’m not aware of
Joined: Aug 2024
Posts: 10
Likes: 8
From: Philippines
I know you guys dont like it when people theorize about these crashes before an official report, but look, its what we do so may I?
Everything ive seen, and in particular the NTSB footage of the guy poking around the tail, suggests the tail rotor drive shaft bonds failed and cut the top of the tail boom open leading to loss of anti torque control, and an immediate yaw leading to loss of lift and low G resulting in the rotor being unloaded and the head hitting the mast and bending the mast at the transmission, ripping the entire lot out of the roof as a seperate event after the severing of the tail boom,
The pics of the inside of the tail boom show about 3-4 scratches where, after peeling that 20cm section open, the vibrating spinning driveshaft started whacking the split open piece of steel on its white side and only had a fraction of a second to work 3-4 lines of the white paint off.
Someone posted the video of the sound enhanced thing a few posts back, I think thats the sound of the TR driveshaft smacking around in its little cover.
Everything ive seen, and in particular the NTSB footage of the guy poking around the tail, suggests the tail rotor drive shaft bonds failed and cut the top of the tail boom open leading to loss of anti torque control, and an immediate yaw leading to loss of lift and low G resulting in the rotor being unloaded and the head hitting the mast and bending the mast at the transmission, ripping the entire lot out of the roof as a seperate event after the severing of the tail boom,
The pics of the inside of the tail boom show about 3-4 scratches where, after peeling that 20cm section open, the vibrating spinning driveshaft started whacking the split open piece of steel on its white side and only had a fraction of a second to work 3-4 lines of the white paint off.
Someone posted the video of the sound enhanced thing a few posts back, I think thats the sound of the TR driveshaft smacking around in its little cover.
Last edited by JeremyThompson; 20th April 2025 at 07:24.
Joined: Oct 1999
Aviation Qualifications: ATPL
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From: Den Haag
It was going fine until you said this:
But, I’m not opposed to the idea that the transmission detaching could have been caused by a combination of dynamic, and aerodynamic forces, resulting from the loss of the tail boom just aft of the mounting point. Why it detached, I have no idea, but I very much doubt it had anything to do with a flailing TR drive shaft. Because of the speed they run at, they experience low torque and so are very lightweight. My earlier remarks were connected to the suggestion of the pax applying pedal.
an immediate yaw leading to loss of lift and low G resulting in the rotor being unloaded and the head hitting the mast and bending the mast at the transmission, ripping the entire lot out of the roof
Last edited by 212man; 20th April 2025 at 10:02.
Joined: Aug 2024
Posts: 10
Likes: 8
From: Philippines
So im not saying the TRDS vibration jolted the main transmission mounts off, im saying the helicopter ended up in a disaster because of the failure of the entire tail rotor and boom, and then that led to the loss of loading on the disc.
When the tail rotor fails, the helicopter spins. That sudden uncontrolled spin throws off the balance of the main rotor, which then can’t keep lifting properly, so it becomes ‘unloaded’ and stops holding the aircraft up. Mast bumping did then occur, but it happened after the main event. It itself was not the main event.
In other words, the tail rotor stops working, and the whole helicopter starts spinning. Because there's nothing for the engine to push against anymore, the main rotor slows down in relaion to the air. And when it slows down, it cant make lift anymore and the helicopter falls.
That falling, is so quick and is effectively immediate, and would have resulted in the pilot pulling back on the cyclic, almost certainly sealing the fate of the rotor mast assembly.
EDIT: i should add, im quite focused on the images that helispotter also refferenced earlier on, where he showed the angle of the mast coming out on an angle from the transmission. Theres no goood foootage or photos yet close up, but it looks like a pretty good indicator of engine induced damage, not from hitting the water. Mast bumping usually bends or snaps the mast but theres no rules about what that must look like. typically with robbies its a completel crack and separation. The 206 mast is prety hefty.
Last edited by JeremyThompson; 20th April 2025 at 13:42. Reason: added mroe context re: tramisssion mast angle, edit 2, terribly worded. try again
Chief Bottle Washer
Joined: Sep 2000
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From: PPRuNe
JeremyThompson you have a severe lack of knowledge about mast bumping which affects the head of the mast, not the base. Your post history indicates a fascination with accidents along with an overall lack of understanding of the backgrounds.
Any more of such contributions to this thread will result in an Access Mask being applied to you for this Forum.
Joined: Aug 2024
Posts: 10
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From: Philippines
Im sorry but im making a valid well educated analysis here but no one is able to understand it because its a bit complicated for me to put in text.
Yes, Mast bumping is typically a thing which happens under power, so is typically, severe at the top of the mast.
But this was not under normal power situation, as torque was lost due to an entire drivetrain component missing.
There have atually been quite a substantial number of number of military related incidents where the bumping has lead to cracked transmission cases.
But for commercial examples, N6181A, September 16 September 12, 2016 - mast bumping event on ground
"The inspector performed a limited inspection and noted substantial damage sustained to the main rotor mast and to the transmission system."
Now im sorry to offend anyone, my posts are meant to be informative. Is there any chance I can maintain an ounce of respect on here ? I resepct everyone else, why is there none available for me?
Yes, Mast bumping is typically a thing which happens under power, so is typically, severe at the top of the mast.
But this was not under normal power situation, as torque was lost due to an entire drivetrain component missing.
There have atually been quite a substantial number of number of military related incidents where the bumping has lead to cracked transmission cases.
But for commercial examples, N6181A, September 16 September 12, 2016 - mast bumping event on ground
"The inspector performed a limited inspection and noted substantial damage sustained to the main rotor mast and to the transmission system."
Now im sorry to offend anyone, my posts are meant to be informative. Is there any chance I can maintain an ounce of respect on here ? I resepct everyone else, why is there none available for me?