PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Rotorheads (https://www.pprune.org/rotorheads-23/)
-   -   North Sea heli ditching: Oct 2012 (https://www.pprune.org/rotorheads/498649-north-sea-heli-ditching-oct-2012-a.html)

cyclic 24th Oct 2012 20:26

CHC aside, where are the rest of the faulty shafts? EC said they knew where they all were, which is obviously not the case. I don't think we should completely reliant on HUMS data to find components prone to failure. I'm sure there will be a lot of head scratching going on at the moment.

morfmedia 24th Oct 2012 20:37

BBC News - Super Puma inquiry finds helicopter fault

HeliComparator 24th Oct 2012 20:50

Cyclic, I agree - clearly the shaft in question was not subject to the 4 hr mandatory download, so something is wrong with the list of shaft numbers in the ASB. I suspect we will be back to all shafts being subject to the AD/ASB. As you say, that should be short term measure and fixing the underlying problem the closing action.

HeliComparator 24th Oct 2012 20:54

I see from the beeb article that our friend JF gets it completely wrong as usual!

Wizzard 24th Oct 2012 20:58

From the BBC website:


Aviation writer Jim Ferguson said: "Unlike the 10 May Bond incident, this emergency saw the shaft crack actually taking out both lubricating oil pumps and hence the immediate water landing was absolutely essential and prevented a far worse outcome than a ditching.
Wrong again Jimbo :ugh::ugh:

heli-cal 24th Oct 2012 21:25

Malabo,

So, as PIC, you're happy to gamble with the lives of everyone else aboard, and to continue flight, despite 'Land Immediately' being the correct course of action?

The aircraft cost is of no consequence in comparison to the lives of those aboard!

HeliComparator 24th Oct 2012 21:39

Complaint sent to the BBC
 
In the news article relating to the recent ditching of an EC225 helicopter in the N Sea, once again the BBC chooses Jim Ferguson to give his opinion on the event, as if it were fact. Unfortunately Mr Ferguson is just a plane spotter and has no technical nor operational experience of helicopter operations. Whenever he is called upon to give his opinion in such matters, he always gets his facts completely wrong, as is the case in this report where he makes completely incorrect statements when comparing this event to the ditching of the Bond helicopter in May - despite what he says, the two AAIB reports show that the problems were virtually identical. This is a sensitive subject up here for the offshore workforce, and the spread of mis-information does not help. I can appreciate that it might be difficult to get statements from people who actually know what they are talking about, but the BBC should resist using Jim even if there is no one else - the BBC should stick to facts as published by the relevant experts such as AAIB, or perhaps the manufacturers and operators (but remembering that they have vested interests). Rather than asking Jim Ferguson, why not just ask the old lady who works in the local laundrette - she would have just as accurate a picture of the facts as Jim does, and might be more entertaining!

HeliComparator 24th Oct 2012 21:43


If the EMERG Lube was working, then yes I would drive the 14nm (thanks for that figure) or 7 minutes to a dry feet landing.
Let's see, 14 miles at the maximum allowed speed of 80kts in 7 minutes - must be a very strong tailwind!

Anyway, if Emerg Lube was working, maybe. If not, definitely not unless you want to die and take everyone else with you. You stand a fair chance ditching in SS6, you stand no chance if the gbx gives up in flight.

jimf671 24th Oct 2012 22:39


... 14 miles at the maximum allowed speed of 80kts in 7 minutes ...
To be fair HC, that might be the answer to the wrong question.

When the emergency started, the aircraft was not at the ditiching site but was a few miles further south and at 3000 feet. Out to the right of the flightpath was a piece of land that was not 14 or 11 or whatever NM further away than the ditching site. On the closest part of that land is a lighthouse and at lighthouses you find a big H.

Of course, Fair Isle does not have the world's most inviting coastline and staying the hell away from it cannot be faulted.

HeliComparator 24th Oct 2012 23:07

New EC ASB out requiring HUMS download every 3 hrs for EC225. Bit of a pain but at least it gets us flying again.

Tcabot113 24th Oct 2012 23:14

Historically HUMS can detect 50% or so of impending failures. It has generally been good at detecting the second occurrence. In this case it failed for whatever reason. HUMS is decent as a second line of defense, it should never be elevated to a go/no go system.

Conclusion should be all shafts inspected (and replaced if needed) prior to next flight and in case of a loss of oil pressure ditch. If the emergency lube is so problematic to give off false failure warnings, it can easily give no indication of a real failure. This would be the Cougar 92 crash all over again.

TC

Camper Van Basten 25th Oct 2012 02:46


Conclusion should be all shafts inspected (and replaced if needed) prior to next flight
Yeah, let's do that.

Inspecting that shaft (visually) is a very long, laborious, and difficult task, especially considering the number of aircraft / flights we're talking about. Replacing it is an overhaul function.

I'm not sure what the best solution is, but that certainly isn't it.

Tcabot113 25th Oct 2012 05:35

CVB

Making sure it did not happen the first time is the most cost effective approach. Having a second identical set of multiple failures is inexcusable. We have seen in this case relying on HUMS is not a substitute for airworthy components.

Also, I do not see a one time visual inspection to keep aircraft out of the drink is unreasonable in light of the current events.

TC

Tcabot113 25th Oct 2012 06:18

TM

Original reports on the first event indicated a detectable manufacturing defect. Visually inspect for that! If it can not be inspected for then yes they all should be grounded until a replacement shaft is available.

If the back up lube actually worked with no false alarms this would be just a minor issue, but it now has a proven 100% failure rate which leaves no choice but to ditch. It will be interesting to see if the lube warning is miswired or has a CWA logic issue.

TC

Pittsextra 25th Oct 2012 07:05


If the back up lube actually worked with no false alarms this would be just a minor issue, but it now has a proven 100% failure rate which leaves no choice but to ditch. It will be interesting to see if the lube warning is miswired or has a CWA logic issue
well maybe the logic that is when something has physically failed no about of lubrication is going to heal it??? I guess in the design of this system if there is other data that over rides the suggestion that lubrication is working OK it gives warning?

Harry the Hun 25th Oct 2012 07:17

At Pitts
 

well maybe the logic that is when something has physically failed no about of lubrication is going to heal it??? I guess in the design of this system if there is other data that over rides the suggestion that lubrication is working OK it gives warning?

Please say again, you are coming in garbled.

obnoxio f*ckwit 25th Oct 2012 07:32

I'm afraid I have had to join HC on this one:

Sir, I have just read your news article concerning the ditching of a Superpuma helicopter in the North Sea on Monday ("Super Puma inquiry finds helicopter fault"). Why does the BBC insist on trotting out the buffoon Jim Ferguson at every opportunity whenever helicopters in the North Sea are discussed? Once again he has proved he is not nearly as qualified as he thinks he is to comment on such issues. His remarks on this event, plus his comments on a recently released report on the May 2012 Bond ditching, are blatantly wrong, yet will be believed by many as they has been given by an 'expert' on the BBC. Surely it is possible to find someone in Aberdeen who actually knows what they are talking about?

Regards

Obnoxio f*ckwit

onesquaremetre 25th Oct 2012 07:36

Minor Issue?
 

If the back up lube actually worked with no false alarms this would be just a minor issue
Don't forget the Bond ditching had a chip warning as well because the shaft moved and teeth started to break up. That doesn't appear to have happened here but the origin of the problem appears similar. Hardly a minor issue.

Pittsextra 25th Oct 2012 07:41

yes I'm sorry, haste and speed.

My point being that in the case of mechanical failure within the gearbox at some point no amount of lubrication is going to help. The false readings given in the case of REDW were suggested as

"it was concluded that a bleed air pressure sensor at the
top end of the specified tolerance could generate an MGB EMLUB caption, even though all the parts of the emergency lubrication system are operating within their specifications."

I'm not sure what the logic is with the system vis if the Emergency Lube is functioning very well when that is not the thing thats going to save you.

Edited to add:- perhaps the error and MGB EMLUB caption was a blessing when the bevel gear vertical shaft has failed.






Harry the Hun 25th Oct 2012 07:45

North Sea heli ditching: Oct 2012
 
Who designed and manufactures the MGB and Emer Lube system, is it EC or some other company?


All times are GMT. The time now is 01:05.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.