Puma incident at ABZ Today

[NorthSeaTiger]

What happened with a Puma rejected take off at ABZ today ? Any news of the cause ?

NST

[Helitemp]

The Bristow Puma G PUMI had a fracture to the fwd spindle lug on lift off at Aberdeen this afternoon. A large open fracture at the six oclock position on the fwd lug of one of the main rotor spindles.:uhoh:

[Aser]

fwd spindle lug
Humm.. I need a translator please, must be another term to use. :confused:

[SASless]

Pretty sharp eyes to have seen that whizzing about over yer noggin!

[NorthSeaTiger]

:eek: oh dear that's a bit nasty :eek:

[Aser]

Thanks Um...Lifting...,
So just plain the hub blade grip or yoke.

[Wizzard]

For information the L2 and 225 rotor head are of a completely different design to the L/L1.
They were very, very lucky
Wiz

[GenuineHoverBug]

There is a brief Telex Info on the subject out from Eurocopter today. A very worrying picture is attached, showing a crack you could place you finger in, if you wished.

This reminds me of the fatal S61N accident on the Norwegian side in 1978.

The detached blade was recovered from the sea floor, and it was found that a crack had opened in the spindle lug. But those guys were enroute ....

[peterperfect]

Will be interesting to see where HUMS features in preventing a potential nasty like this ?

[Phil Kemp]

The same thing happened to TIGC, in 1982 at the NW Hutton. The spindle cracked at the 12 o' clock position and some fast and very wise decision making on the part of the crew, to put the machine back on the deck of the Balder, means that they are still here to talk about it!

The spindle design is similar on the Sikorsky/Aerospatiale fleet of that era, and helicopters from both manufacturers have suffered from a number of fatal consequences from failures in this area.

It will be very interesting to understand the origin of this particular failure.

Well done to the crew!

[FlightOops]

For the sake of the ignorant, could somebody explain what exactly the crew "experienced" in order to make the decision to land.

Clearly the fault is major and could have had a catastrophic outcome had they not been able to put it down, however from the SASless post ("Pretty sharp eyes to have seen that whizzing about over yer noggin!") and from the explanation from Um...Lifting (merci, petite chou) it is not clear what indications the crew would have had.

Just for the curious.

Thanks and ditto "well done the crew",
FO.

[Geoffersincornwall]

The bulletin said that the pilot experienced a sudden thump followed by a vibe.

Good decision

G

:ok:

[Mikila1A]

Have not seen or can find the Telex from here on the left side of the pond.

Anyone got a copy of the Telex or the picture?

[Forcelink]

Yes, some of us have seen this all before!

Initial Telex info from EC:
TELEX INFO – EUROCOPTER – TELEX INFO – EUROCOPTER – TELEX INFO – EUROCOPTER T.F.S. No. 00000335 dated October 17, 2006 EUROCOPTER – MARIGNANE – TLX 42506F Page 1 of 2 TELEX INFO – EUROCOPTER – TELEX INFO – EUROCOPTER – TELEX INFO - EUROCOPTER
T E L E X I N F O R M A T I O N
AIRCRAFT: AS 332 Civil Version(s): C, C1, L, L1
Military Version(s): B, B1, M, M1, F1
AIRCRAFT: AS 532 Military Version(s): AC, AL, SC, UC, UE, UL
ATA : 62
SUBJECT: MAIN ROTOR HEAD SPINDLE
Failure of a Yoke
Dear Customer,
EUROCOPTER informs you that an Operator has discovered a crack in a spindle yoke, which led to the failure of the section. The failure is located on the leading edge, in the lower section of the spindle yoke (see Figure 1).
The event occurred in hover flight before performing an offshore flight. The crew heard a muffled noise combined with high-amplitude vibrations. The pilot decided to land immediately, and landed with no further damage.
The spindle concerned, P/N 332A31-1485-06, is in the post MOD 0743100 definition status and had logged 3032 operating hours at the time of the incident.
Initial investigations carried out on site have not shown any anomaly able to explain the failure. The spindle will soon undergo laboratory examinations in order to confirm the initial investigations which have evidenced a fatigue type crack affecting a significant part of the failure. The failure shows a large number of macrographic marks which are indicative of rotor stops.
EUROCOPTER will keep you informed of the conclusions of the investigations and analyses into the cause of this event.
TELEX INFO – EUROCOPTER – TELEX INFO – EUROCOPTER – TELEX INFO – EUROCOPTER T.F.S. No. 00000335 dated October 17, 2006 EUROCOPTER – MARIGNANE – TLX 42506F Page 2 of 2 TELEX INFO – EUROCOPTER – TELEX INFO – EUROCOPTER – TELEX INFO - EUROCOPTER

Subsequently Alert SB 05.00.67 Released with inspection requirements for the spindle yoke.

Unfortunately, I could not import the images of the crack (fig 1) onto PPRUNE.

"rotor stops"....now there is a good username!!!

[Thridle Op Des]

I seem to recollect discussing the NW Hutton incident with the pilots concerned that they had actualy initiated forward cyclic input when there was suddenly a huge 1 per and a similarly large split in the track. With great presence of mind they managed to haul the 332L back on deck without anything falling off.

Eurocopter seem to have this habit of forgetting their past experiences to prevent future incidents - I'm thinking of identically poorly designed inclined drive shaft covers on the 330J and 332L.

TOD

[OffshoreHeli]

Latest

http://news.bbc.co.uk/1/hi/scotland/north_east/6085894.stm

[crud12001]

What will this mean to crew change flights and BP's Jigsaw.

Will there be delays in flights going offshore?.

Anybody know??

CRUD!"))!

[Pan Pan Splash]

PeterPerfect
Will be interesting to see where HUMS features in preventing a potential nasty like this ?


As I undertsand the aircraft is fitted with a very mature HUM system. This is one of those instances where to argument for and against cockpit displays for HUMS systems rears its head. Essentially, HUMS data would not predict this type of sudden failure, it would detect it after the event, but even then, I suspect it would only show as 1R or probably 4R vibration, in which case, the first rectifcation call would probably be a track and balance. Sadly, in my opinion this is a case where the HUMS probably would be useless, and the Pilot made a great call in aborting the take off.. Well done that man:ok:

[coalface]

In answer to CRUD12001's question, the extra inspection shouldn't affect the daily flying schedules as NS helicopters seldom fly more than 10 hours a day. The extra inspection will be part of the end of day inspection which already includes a detailed inspection of main rotor head parts. I am assuming the extra inspection is just a very close visual of the affected parts.

As to Jigsaw, their aircraft are L2s which have a totally different main rotor head so are not affected by this problem.

[lynx247]

When the crew aborted, did they land immediately and shut down on the spot, or attempt to ground taxi back to base with the vibration? Or rather, would the vibration have forced a land and shut down - i.e. what procedure should be followed in this instance?

If anyone can post a picture of the fracture, I'd be keen for a look.

[OffshoreHeli]

If you get a bang and vibration which forces you to make the decision to reject then where you stop is where everybody gets off. This is what happened on the day.

[HeliComparator]

PPS - you are right, unfortunately in this case HUMS would not have picked up the problem until after the crack let go - by which time it was pretty obvious to the pilots!

lynx - they made the very good decision to shut down immediately. By chance they had started to transition on a cross runway, so they rejected the takeoff and stopped clear of the main runway and right outside the airport fire station, which I guess is as good a place to park as any under the circumstances. There is a picture in the Eurocopter alert telex, which you can download from Eurocopter's TIPI website (though you have to be registered).

HC

[LEGAL TENDER]

Sorry.. Off Topic, but thought I'd take advantage of the ABZ thread without starting a new one.
Could any ABZ based Bond pilots send me a PM please?

thanks