Twisting By The Pool - Fiji Style

[touring_pilot]

Seven people survived a helicopter crash on Fiji's Treasure Island last night.
The Eurocopter they were in was trying to land when it crashed, the Fiji Broadcasting Commission reported.
It is believed the aircraft may have been caught by a strong gust of wind.
A witness, Bob Carroll, wrote on Facebook: "A beautiful day trip to Treasure Island changed dramatically as an inbound helicopter attempting to land on the Treasure Island helipad only 50m from where we were dining caught a wind gust that sent it into a tree and then crashing into another tree right next to the pool ... scary but thank God all got out of the chopper and we are all OK."
- NZ Herald (http://www.nzherald.co.nz/)


Seven people survive chopper crash in Fiji - World - NZ Herald News (http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11565548)

[spinwing]

Mmmmm ...

Helipad not particularly over size is it ... :eek:

[Heliringer]

Video.

Watch: Helicopter crashes at Fiji resort, seven on board escape | Stuff.co.nz (http://www.stuff.co.nz/world/south-pacific/75429212/watch-helicopter-crashes-at-fiji-resort-seven-on-board-escape)

[Peter3127]

Would be one hell of a gust ...

Has that "camera strap around the collective" look?

"Hey Hank, get a photo of that nice beach". "OK Honey" .... :yuk:

[John Eacott]

Looks suspiciously like a strong onshore breeze from the approach and the nose low (initial) touchdown; if so then I'd have opted for a crosswind rather than downwind landing. Speculation only at this stage, of course.

I suspect the person taking the video may have thought themselves a bit lucky, though. That's as close as I'd ever want to get to a turning and burning rotor :oh:

Talk about brown trouser moment.....

[Heliringer]

If we are speculating I'd say landed collective not fully down, moved the cyclic and it started to rock on the toes due to a forward C of G issue (overloaded). Bit of panic, snatched the collective and binned it.

Didn't really notice too many white caps or spray from the water so not that windy or at least nothing the AS350 couldn't handle.
New to type or just a low timer?

Glad everyone walked away.

[Gordy]

Heliringer

If we are speculating I'd say landed collective not fully down, moved the cyclic and it started to rock on the toes due to a forward C of G issue (overloaded). Bit of panic, snatched the collective and binned it.

Didn't really notice too many white caps or spray from the water so not that windy or at least nothing the AS350 couldn't handle.
New to type or just a low timer?

Agreed 100%

[John Eacott]

The first 20-30 seconds show an approach from camera left, crabbing in as if in a crosswind, then very twitchy turn to his right and touch down on the toes of the skids.

Maybe a bit of both downwind plus collective not fully down?

[John R81]

Had someone demonstrate to me in my 120 the danger of getting a strong gust under the tail by flying backwards at no more than 15 knt. No warning, but wind got under the tail and pitched us nose down just like that. Can't apply rear cyclic - risk = chop the tail - so "wait it out".


Demo over an airfield with adequate height to demonstrate safely so nothing more than a twitching sphincter. It put me off setting down downwind as I reasoned that the same could happen from a tail-wind, and close to ground / buildings I would have no time to recover.


The speed of attitude change looked just like that to me; and he had no room to recover.




Not saying there was not some other cause, just that an on-shore breeze of "less than you might think" might do exactly that.

[Johnny31297]

Well, I assume something or someone bumped the cyclic, possibly the front sear pax while getting out. Take a look at that freeze frame just before the heli pitches forward. That's a lot of disk tilt for a gust, don't you think?

http://i.imgur.com/k1dyGZc.jpg

[Mattyt]

Hi, new here so please be gentle :)

Just an observation, but on this crash and a couple of others, (the shaking to pieces in Brazil etc,) when things go wrong in the AS350, the front windscreen/ Cabin, seems to detach from the roof just infront of the main rotor very quickly. In the event of an accident, the pilot become exposed very quickly. Is this a weakness in the 350/355 model ?

[hueyracer]

@Nescafe:

I like your story....so what did you do other than telling this story here?

Did you actually file a report with the FAA/CAA?
Did you talk to the Director of Operations of this company?

I totally agree you did the right thing by saying something to the pilot-but it does not stop there..

If one of my pilots would do such things, i would appreciate a feedback from the passengers (which is why we hand out cards).

[zalt]

Please don't take offence Nescafe but perhaps going back to the hotel, looking in the phone book and calling the Fiji CAA might have been more appropriate.

[wanabee777]

Has anyone here had any experience with the Civil Aviation Authority of Fiji (CAAF) ?? (http://www.caaf.org.fj/index.php)

Just curious.

[Hot and Hi]

...someone bumped the cyclic, possibly the front sear pax while getting out.
Which cyclic to you mean? For sightseeing ops, it is normal practice to remove the secondary controls. In particular, as this was a 1+6 pax configuration, I believe it is almost impossible to have a cyclic on the front pax (i.e., left) side.

[RINKER]

I haven't seen the video due slow internet here.
But how about an unfortunately timed hydraulic failure.

R

[wanabee777]

Thanks H & H.

The reason I asked the question was because of a recommendation by our dispatcher one night on a flight from LAX to SYD.

We had a passenger who was having chest pains and we were formulating a diversion plan in case the situation worsened.

Even though NAN was our closest suitable airfield, our dispatcher recommended that, if at all possible, we use NOU due to "political instability" in Fiji.

As it tuned out, we were able to proceed to SYD.

[Gordy]

Rinker:
But how about an unfortunately timed hydraulic failure.

The accumulators on the Astar will give you about 2-3 full cyclic movements after Hyd failure, so chances are this has nothing to do with Hydraulics.

[John R81]

Went through frame by frame. The first sign of movement in the disk that I see is the rearward blade lifting way above the track of the other 2, which are only slightly below level. Don't see how a cyclic movement would do that. My guess is that this is a downwind settle with onshore gusting wind.

[fencehopper]

https://www.facebook.com/ruy.flemming/videos/10208233629229257/

another but this was a near miss

[evil7]

WtF! Are these guys on their first flight in this environment??:(:=

[Reely340]

John R81: Can't apply rear cyclic - risk = chop the tail - so "wait it out".There! you said it! I've been trying to get a concise answer about exactly that topic ever since I got my license, none of the CPLs I talked to could clarify:

Is it normal that at zero pitch & flight idle, full aft cyclic will trash the tail?

There is that US Army video of old instructing about mast bumping. Initially they demostrate how the rotordisk of a Huey (on the ground) will nicely tilt according to cyclic input. I was amazed at the angle that rotordisk can move.
Then there were accident reports of Robbos cutting off their tails inflight.
Okay, both are of semi-ridig see-saw type. :ouch:

But now you were implying that "emergency strength" rear cyclic on an AS350 rotorhead would chop the tail. :eek::eek:

So would I trash my S300-C tail when applying full aft cyclic at flight idle (e.g. no pitch -> no upward coning)
Nobody warns me about that, the AFM has no restricting as well.

[FH1100 Pilot]

No, Reely, you should be able to pull full aft cyclic in most running helicopters, even on the ground at flat pitch. Really, Reely. In fact, the procedure for bleeding the hydraulic system of the FH1100 called for repeated *FULL* fore and aft excursions with the cyclic while at 100% NR flat pitch on the ground. Even though I knew it wouldn't hit...it was pretty nerve-wracking, let me tell you. Same with the Bell 206 - it won't hit. And I wonder if there are any helicopters certified in which full aft cyclic would cause the blades to hit the tail under normal circumstances? Would that even be allowed?

But here's the problem: If your tailboom is coming *up* (like due to a gust of wind) while your main rotor blades are tilting *down* back there (due to your aggressive over-reaction)...well, could be trouble! Things can get quite dynamic back there.

[malabo]

Wind not a factor, there was no gust. Pilot had good smooth control of the aircraft and was within an inch of setting it down nicely. Pad size was reasonable for the operation.
I'm with Peter3127, somebody else pulled collective.

[jymil]

The facebook video was for sure due to overcontrol when the pilot was surprised by the slope gradient. I also don't think a gust can ever be the sole cause of the results we've seen on the Fiji video.

[[email protected]]

Agreed jymil - the FB video clearly shows that an inappropriate cyclic movement can rapidly change the attitude of the helo - it is a natural pilot reaction if you feel the tail going down to push forward with the cyclic - if you panic and shove it forward while you still have some collective applied then the videos amply demonstrate what happens.

JohnR81 - the rearwards flight demo has been a standard one in the military for many years. The idea is to make pilots aware that the combination of groundspeed and windspeed must be considered when manoeuvring. In particular, the demo should highlight that, when trying to arrest rearward movement, care must be taken with forward cyclic to avoid a rapid nose down pitch and, if it is experienced, the recovery should be led with collective.

[Nubian]

Fiji video,

By the way the helicopter touches down nose low, suggest that it is having a CG far in front (not uncommon in the 350, and especially if it is fitted with the bench). In a normal downwind landing (with CG within limits) you will sit with more aft cyclic than if you do the same landing into wind. This chap is landing on an edge of a wall up to the helipad, and I will not be surprised if he get some ''lift'' that lifts his tail more than he expects. It appears also that the helicopter is rocking/ touching aft a bit hard, so the pilot may have pulled collective to soften the landing, but with the combination of tailwind and collective-intput finds himself airborne. Now, if you have a foreward CG in this scenario, you'll run into the aft stop of the cyclic and you will accelerate forward if you don't floor the collective. You pull pitch and the nose will come up, but if there is palm trees in your way of escape, you'll end up on youtube....

Facebook video,

The guy don't misjudge the slope gradient...... he misses the pad (marked by 4 dark point, lights?!), by landing too far back and over controlling in the recovery. Similar to the B3 trying to land on the dolly in CA, but with a much happier outcome.

From the 2 videos, I find the general handling of these pilots to be fair to poor and suspect that these pilots don't have much experience.

[krypton_john]

It seems v ery unlikely to me that anyone other than the pilot could have pulled the collective. Those Island Hopper ships are all single control and the pilot would have had his hand controlling the lever.

[Reely340]

FH100: But here's the problem: If your tailboom is coming *up* (like due to a gust of wind) while your main rotor blades are tilting *down* back there (due to your aggressive over-reaction)...well, could be trouble! Things can get quite dynamic back there. First of, thx a lot for that infomation, I was hoping full aft cyclic would be basically tail safe.

However, you're saying, that a rotodisk spinning at 100% Nr might be caught by the tail being pushed up (by external forces, further than aft cyclic is able to tilt back the disk).

I can easily see that happen with them semi rigid seesaw two bladed rotors, a gust whacking the tail into the rotordisk. (Robo et.al.)

I can picture a fully articulated rotorhead to be flexible enough (flapping hinge) to leave the rotordisk (inertia!) unaffected when the fuselage bucks its tail.

But can that happen on rigid BO105/BK117/EC135 rotors or bearingless AS350s as well?
I'd have guessed that all ac with mast moment indicators (and limits) won't allow the bladetipspath to deviate significantly from being in an plane perpendicular to the mast, w/o breaking it, of course.

( Then again, maybe I wrongly count bearingless rotorheads as similar to rigid ones. Does an AS350 have mast moment limits?)

[Devil 49]

"Does an AS350 have mast moment limits?"

No.

[Reely340]

Thx. Which means tail wind gusts CAN kick the AS350 tail into the rotordisk, right?