Helicopter ditches . . .

Anything goes in here.....
User avatar
Rich H
Posts: 9314
Joined: Sun Jul 31, 2005 10:11 pm
Location: Preston

Re: Helicopter ditches . . .

Post by Rich H » Fri Oct 26, 2012 7:18 am

What he said.
The gear will be machined separately to the shaft most likely then EBW
May even be a different steel for the gear/shaft
1994 Lotus Esprit S4 - Work in progress
1980 Porsche 924 Turbo - Funky Interior Spec
2004 Smart Roadster Coupe - Hers

User avatar
Scotty C
Meat
Posts: 8352
Joined: Thu Mar 10, 2005 12:11 am
Location: Aberdeen

Re: Helicopter ditches . . .

Post by Scotty C » Fri Oct 26, 2012 8:19 am

if its the same problem that they had that caused the deths a couple of years ago why have all the shafts not been changed?
"Here for a good time not a long time"

User avatar
kerryxeg
Posts: 1035
Joined: Tue Mar 21, 2006 2:15 pm
Location: Aberdeen

Re: Helicopter ditches . . .

Post by kerryxeg » Fri Oct 26, 2012 8:36 am

I don't have anymore info than exists in the investigation report,but fwiw.

A batch of shafts was recalled after the last incident as it was thought this was a bad batch. This repeated failure indicates a more fundamental issue could be the cause. The issue seems to be vibration in the system leading to shaft failure. So this could be related to several components and the design. There are 2 gearbox types, just heard the version not involved in the incident will be allowed to fly.

woody
Posts: 5637
Joined: Mon Dec 26, 2005 4:03 pm
Location: Southside Triangle

Re: Helicopter ditches . . .

Post by woody » Fri Oct 26, 2012 8:44 am

Scotty C wrote:if its the same problem that they had that caused the deths a couple of years ago why have all the shafts not been changed?

Scotty, the regulators will have investigated the previous event. It seems they have instigated a stricter inspection schedule (again, I only skim read the report). This decision will have been reached based on anaylsis of the root cause of the fractures; the design of the shaft, the affected batch of part & serial numbers (was there a time when the shaft was made by a different supplier or small changes made affecting only some production), what corrosion coating is used/present & it's effectivity, what vibes were recorded by the various sensors & their relationship with part stresses. What is the fatigue life of the shaft (again not familiar with helicopters, but as a major rotating part it's likely to only be allowed to fly x amount of cycles) Perhaps the shafts were visuallly inspected, the AD introducted NDT inspectiuons like Eddy Current or a local FPI. All of which would be control factors to allow the aircraft to fly with the same parts installed.

From what I've read this shaft was not from what was considered the pool of Part and Serial numbers likely to be affected and would therefore not have been included in the previous AD and not subject to any increased observation. Again, have to note all of the above is my educated guesswork and I have no knowledge of this incident.

User avatar
Rich H
Posts: 9314
Joined: Sun Jul 31, 2005 10:11 pm
Location: Preston

Re: Helicopter ditches . . .

Post by Rich H » Fri Oct 26, 2012 10:04 am

Bear in mind that the shaft failures might actually be a symptom of another fault.

Again not familiar with the arrangement but it could be a change in another component that has changed the operating environment for this part.
Even a change in operating procedures could do it. Yanking on the rotor brake to speed up turn arounds? A change in gearbox oil supplier?
Could be human error - we have filled several Tornado hydraulic systems with engine oil and several engines with hydraulic oil...

Could potentially be almost anything if it's a secondary failure.

Flight safety is protected by layers and layer of safety checks adn balances, but they have holes and sometimes they line up
Image

With several examples now avaialble for comparison you would like to hope the cause can be found and corrected.
1994 Lotus Esprit S4 - Work in progress
1980 Porsche 924 Turbo - Funky Interior Spec
2004 Smart Roadster Coupe - Hers

User avatar
neil
Posts: 3259
Joined: Fri Apr 06, 2007 1:55 pm
Location: Aberdeen

Re: Helicopter ditches . . .

Post by neil » Fri Oct 26, 2012 10:11 am

Looks like the design of the shaft has changed, the newer one being the one with the problems:
http://www.stepchangeinsafety.net/templ ... ileID=1563
Based on this they've now got 9 of the older Super Pumas flying. EC225 and anything else with the new type shaft is still grounded.
Exige V6

User avatar
tut
Barefoot Ninja
Posts: 22975
Joined: Tue Mar 15, 2005 5:53 pm
Location: Tut End, Glen of Newmill

Re: Helicopter ditches . . .

Post by tut » Fri Oct 26, 2012 6:03 pm

The bottom line is that whatever the fault is it needs rectifying before another helicopter of that type takes off again.

It does not need Einstein to work that out.

tut|

woody
Posts: 5637
Joined: Mon Dec 26, 2005 4:03 pm
Location: Southside Triangle

Re: Helicopter ditches . . .

Post by woody » Fri Oct 26, 2012 6:53 pm

tut wrote:The bottom line is that whatever the fault is it needs rectifying before another helicopter of that type takes off again.

It does not need Einstein to work that out.

tut|

Can't see anyone arguing that one. :)

User avatar
Fluoxetine
Posts: 1423
Joined: Thu Aug 17, 2006 5:57 pm
Location: Baile Átha Cliath / Abergloom

Re: Helicopter ditches . . .

Post by Fluoxetine » Sat Oct 27, 2012 12:19 pm

Our logistics team have indicated it may be months before this is resolved, as opposed to days or weeks... :shock:

User avatar
robin
Jedi Master
Posts: 10546
Joined: Mon Mar 27, 2006 1:39 pm

Re: Helicopter ditches . . .

Post by robin » Sat Oct 27, 2012 4:45 pm

Does this mean that people end up spending longer off/on shore due to reduced availability of aircraft?
I is in your loomz nibblin ur wirez
#bemoretut

User avatar
rossybee
Posts: 11093
Joined: Tue Mar 15, 2005 9:13 pm
Location: Dundee

Re: Helicopter ditches . . .

Post by rossybee » Sat Oct 27, 2012 4:59 pm

robin wrote:Does this mean that people end up spending longer off/on shore due to reduced availability of aircraft?
That opens a whole different can of worms ref fatigue/increased accidents etc.

Current Vantage system utilised in North Sea is 21 days max working.
Ross
---------
1972 Alfaholics Giulia Super
2000 Elise S1 Sport 160
2004 Bentley Conti GT
2017 Schkoda Yeti
2x Hairy GRs (not Toyota)

Now browsing the tech pages :mrgreen:

:cheers

User avatar
tut
Barefoot Ninja
Posts: 22975
Joined: Tue Mar 15, 2005 5:53 pm
Location: Tut End, Glen of Newmill

Re: Helicopter ditches . . .

Post by tut » Sat Oct 27, 2012 5:33 pm

Very unlikely that they will change their work schedules and conditions Robin, this has happened in the past and I remember thirty years ago that there was something similar and they went out by ship.

It will be sorted out shortly and everything will return to normal.

tut

JohnStewart
Posts: 895
Joined: Wed Jun 14, 2006 6:07 pm
Location: Kintore
Contact:

Re: Helicopter ditches . . .

Post by JohnStewart » Sat Oct 27, 2012 8:28 pm

rossybee wrote:
robin wrote:Does this mean that people end up spending longer off/on shore due to reduced availability of aircraft?
That opens a whole different can of worms ref fatigue/increased accidents etc.

Current Vantage system utilised in North Sea is 21 days max working.
Yes, for a short period of time, there will be people who have spent longer offshore than they should have, but I believe the helicopter operators are already pulling in aircraft from other parts of the world to assist, and sometimes using different aircraft from their Southern North Sea bases (e.g. 11 or 12 seat helis instead of the usual 18 or 19).

With regards the Vantage system (my day job), it is configurable on an operator by operator basis what warnings they want to put in place (e.g. x days out of y for example). Minimum rest period warning level is normally 1/3 of previous trip (e.g. 7 nights onshore for a 21 night offshore trip), but there are some installations that are still working on a 28/28 rota for example (commonly US drilling rigs). The current POB screen for example can be sorted by nights offshore, to quickly identify those who have been offshore the longest on a location, but having said that, we've done a number of ad-hoc reports this past week giving operators lists of all their people offshore across all locations including arrival date and trip duration so they can prioritise passengers and optimise their use of helicopters. For example if one heli was available to go to a field with 3 platforms, they might pick 8 from one location, 7 from another and 3 from a third instead of doing 18 from a single location.

The last time there was fog for about a week, they did have vessels lined up to transport passengers, but there are limitations on that (max 12 I think) so it would be a last resort.

User avatar
rossybee
Posts: 11093
Joined: Tue Mar 15, 2005 9:13 pm
Location: Dundee

Re: Helicopter ditches . . .

Post by rossybee » Sat Oct 27, 2012 8:52 pm

Yep, our nightshift just left having done 23 nights, so they couldn't work the last 2 nights.

I am ad-hoc :roll:
Ross
---------
1972 Alfaholics Giulia Super
2000 Elise S1 Sport 160
2004 Bentley Conti GT
2017 Schkoda Yeti
2x Hairy GRs (not Toyota)

Now browsing the tech pages :mrgreen:

:cheers

User avatar
Eric K
Posts: 602
Joined: Wed Mar 28, 2007 12:04 am
Location: Old Aberdeen
Contact:

Re: Helicopter ditches . . .

Post by Eric K » Sat Oct 27, 2012 10:26 pm

rossybee wrote:I am ad-hoc :roll:
Don't do yourself down mate. ;) :mrgreen:

Cheers,

Eric :)
Slow, slow, quick, quick, slow ...

Post Reply