Sky Shuttle AW139 ditches in HK Harbour
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Birdstrike? Hmmm
So it looks like the aircraft entered the water minus the entire tailrotor assembly. Maybe its just me, but I can't get my head around the idea that a birdstrike caused this sort of immediate, catastophic damage.
Any 139 engineers care to comment on the construction of the upper part of the vertical stab and how the tailrotor gearbox attaches to same?
JW
Any 139 engineers care to comment on the construction of the upper part of the vertical stab and how the tailrotor gearbox attaches to same?
JW
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Well done to the crew very well handled...looks like to me from all the photos.a tail rotor problem.. I also see from the video that nasty peice of work the gray haired New Zealander is still mincing around...
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Closer examination of media photos show not only a loss of the TR blades and TR gearbox assembly, but also part of the vertical tail boom holding these up. I seriously doubt if a birdstrike would have caused such catastrophic failure - maybe the TR blades but not so far down.
Regulars to this forum will recall this thread:
http://www.pprune.org/rotorheads/386...ing-doh-5.html
Although the tailboom of the SkyShuttle snapped in a different spot, it would be educational to review the discussions in that thread. In particular, note the effects of ground taxi on tail boom structures.
Regulars to this forum will recall this thread:
http://www.pprune.org/rotorheads/386...ing-doh-5.html
Although the tailboom of the SkyShuttle snapped in a different spot, it would be educational to review the discussions in that thread. In particular, note the effects of ground taxi on tail boom structures.
Just beating the air into submission!
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Having suffered large FOD ingestion through the tail rotor whilst in the hover, albeit in a Lynx, I too find this sort of damage due to a bird stike difficult to understand. It would seem to be a structural failure due to very high stress forces to make such a clean break. I summise that the departure of a TR blade from the assembly would give the necessary high stress force to do such a thing. The outcome of the inquirey will be interesting and for those of us flying the AW19 it can't come quick enough. A big BRAVO ZULU THE THE CREW 
. CRABO.
. CRABO.
Having been certified to the very latest FAR/JAR requirements, certification would have included Bird Strike Protection (2 lb Bird if I recall) on a number of areas, including an advancing TRB at VNE.
Several years ago, I was shown a video of an S-76 TRB Bird Strike Certification Test using a 2 lb pheasant and the outcome for the pheasant was not good (Fluffy splatter), but amazingly the blade appeared intact.
Of course, it could have been a dragon.
Several years ago, I was shown a video of an S-76 TRB Bird Strike Certification Test using a 2 lb pheasant and the outcome for the pheasant was not good (Fluffy splatter), but amazingly the blade appeared intact.
Of course, it could have been a dragon.
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Main large soaring bird in the area is the Black Kite. All rumours at the moment.
Chinese black Kites ( Milvus migrans )
Weight: 650 - 940 g (2)
Also known as:Yellow-billed kite French:Milan Noir KingdomAnimaliaPhylumChordataClassAvesOrderFalconiformesFamilyAccipitridaeGenusMilvus (1)SizeHead-tail length: 55 - 60 cm (2)
Chinese black Kites ( Milvus migrans )
Weight: 650 - 940 g (2)
Also known as:Yellow-billed kite French:Milan Noir KingdomAnimaliaPhylumChordataClassAvesOrderFalconiformesFamilyAccipitridaeGenusMilvus (1)SizeHead-tail length: 55 - 60 cm (2)
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Today's news report which shows the damage to the tail rotor in more details while the ship is being disassembled and inspected. There is also a short interview with a Sky Shuttle engineer (who doesn't reveal anything). Bird strike still unconfirmed.
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Perhaps this is a question for Nick Lappos, but I'm sure Sikorsky originally explained at length when the S-92 came out that the latest FARs had a far greater birdstrike requirement than the ones that applied to earlier generations like the S-76. Certainly that was the Shell Aircraft postion when they recommended phasing out older types for 7/7=1.
Sikorsky did seem to back track on this when the birdstrike occured on the PHI S-76C++ the GOM last year. Something about BCAR validation of the glass screen but not the aftermarket screens?
Sikorsky did seem to back track on this when the birdstrike occured on the PHI S-76C++ the GOM last year. Something about BCAR validation of the glass screen but not the aftermarket screens?
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Like Heli Aviator, I can't see a birdsrike in a FAR/JAR 29 latest amendment aircraft causing quite that much damage. Forward speed would have been relatively low (just through Vtoss).
I once suffered a full birdstrike (seagull) about 100nm from Aberdeen to an S-76A at 145kias close to the inboard top of the LH windscreen (glass heated) and the bird just bounced off with only some liquid entrails making their way into the intake and making a smell.
I once suffered a full birdstrike (seagull) about 100nm from Aberdeen to an S-76A at 145kias close to the inboard top of the LH windscreen (glass heated) and the bird just bounced off with only some liquid entrails making their way into the intake and making a smell.
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AWs responsibility
Whatever the case maybe, we hope that AW will come up with a preliminary report ASAP. As operators we must be kept informed on the actual cause of this accident. The Doha incident way of keeping us informed is not acceptable especially when we get better insights from within the industry! Over to you Agusta.
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Look closely at the video, main structure appears to be intact apart from the casting the TRGB attach's to, main parts missing is the carbon fibre rear fairing, not primary structure.
Nothing even similar to A7-GHC.
S
Nothing even similar to A7-GHC.
S
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If you freeze the vid at R101's post #57, you'll notice a whole section of the rear end spar of the vertical boom has been torn off. It appears to point towards enormous stresses having been built up in that fracture line before the TR forces finally tore that section off. It could be that the bang was purely consequential and not the cause of the accident. No bird, not even an eagle or kyte could have done so much damage. And besides, with smithereens of the TR now lying on the seabed, I think it would be very difficult for any regulator to arrive at any finding of a birdstrike, unless there are obvious traces on the surface of the remaining boom, but we're not hearing that.