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North Sea Helicopter ditching 10th May 2012

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North Sea Helicopter ditching 10th May 2012

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Old 18th May 2012, 21:46
  #181 (permalink)  
 
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EASA AD No.: 2012-0087-E

http://ad.easa.europa.eu/blob/easa_a..._2012-0087-E_1

The plot thickens......
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Old 18th May 2012, 22:14
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So, EC had identified the faulty shafts but now they're not so sure. We have gone from continuing to monitor, to ditching (perfectly acceptable to EC), to 6 hrs between downloads, to 4 hrs and back to 5 hrs to accommodate certain operators and now 3 hrs if you have a newish shaft. Presumably if the shaft has done more than 500 hrs it is likely to be ok - test flying phase complete. The incident was 8 days ago and the goalposts have moved again. Fill you with confidence?
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Old 18th May 2012, 22:17
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Two Questions are begged....

Why 500 Hours?

Why not simply "REMOVE" all suspect shafts and return them to EC?

After all....we are not looking a vast number of these things in the fleet are we!

Last edited by SASless; 18th May 2012 at 22:18.
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Old 18th May 2012, 22:20
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thankfully not a big problem for aberdeen operators at the very least.

all are equiped with m'arms and all downloaded between flights. just got to look at a different parameter.

May not be good for length of flights tho.

Last edited by ironchefflay; 18th May 2012 at 22:21.
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Old 18th May 2012, 22:26
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So you have the choice, the 5 hr 225 or the 3 hr 225, which one do you want to take offshore? Which one does your customer want you to use? I think it is a bigger problem than it first appears.
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Old 18th May 2012, 22:36
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Nothing, you are quite right, there is nothing that can be done.
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Old 19th May 2012, 01:33
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10 shafts per batch, so 9 remaining. None of which are in the UK, according to EC. G-REDW had the only one.
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Old 19th May 2012, 06:39
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So day VFR only presumably to make a ditching more survivable...but why is there not a sea state limit?
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Old 19th May 2012, 06:53
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Not just a batch problem

if you re read the AD you will see that it is applicable to all shafts with a serial number M0370 or greater and less than 500 hours so it appears that EASA are not convinced that this is a batch problem. I imagine the 3 hours limitation says something about their view on predicting this type of failure with HUMS.

I wonder how many 225s up in Aberdeen it will effect?
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Old 19th May 2012, 08:05
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Iron

It wasn't sarcasm, it is very easy to misinterpret the written word. I fully agree, there is nothing we can do. That doesn't make the situation any better though.
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Old 19th May 2012, 08:45
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Greyarea. EASA weren't the only sceptical ones...
L2s and (more so) S92s are probably about to take up the majority of longer flights.
My wonder is: with the speed at which the issues in EADs are typically rectified, how long will this drag on for?
Too long and it may well add a fair few nails in the coffin of any future development of the puma.
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Old 19th May 2012, 10:20
  #192 (permalink)  
 
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Honestly, I think that there are a lot of candidates for the "Conjecturing Olympics" contributing to this thread. There could be entrants for events like:

Jumping to conclusions
Running around in circles
Punching above your weight
Swimming out of your depth
Skating on thin ice
Shooting in the dark
Tossing things into the ring
Rocking the boat
Crossing swords
Leaps of logic.

It's all very entertaining to watch though.

Last edited by Colibri49; 19th May 2012 at 10:21.
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Old 19th May 2012, 10:25
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Sea state limit?

Daysleeper,

So day VFR only presumably to make a ditching more survivable...but why is there not a sea state limit?
Good point!! There is of course a sea state limit - SS6, which is the "demonstrated" limit of the floatation kit. This equates to 6 metres.

These are weather reports received in Aberdeen from two offshore installations on 25 Oct 2011:

Time: 0708hrs
Wind: 124 at 53kts gusting 60kts
Cloud: 8/8 at 1500ft
Visibility: 11km
Temp: 11
Dew point: 8
QHH: 1002mb (hPa)
Significant wave ht: 6.5metres
Max wave ht: 10metres
Additional info: 'Within limits of DACON scoop - this is the only means of rescue available at this time'.
Time: 0925hrs
Wind: 130 at 50kts gusting 60kts
Cloud: Clear
Visibility: 8km
Temp: 11
Dew point: 7
QHH: 1003mb (hPa)
Significant wave ht: 7metres
Max wave ht: 11metres
Had Bond 88R ditched that morning, do you think the outcome would have been the same?

Obviously, you would not have expected anyone to be flying that morning, wouldn't you? Wrong! Only the pilots of one North Sea operator declined to fly that morning. The other two continued to fly as usual. As you can imagine, this caused problems for the company not flying, as the oil company clients started asking questions! Which lead to the management demanding answers from the pilots. Fortunately, all the pilots (around 20) refused to change their minds about not flying - only a decrease in sea states would have done that.

You would also expect that all three North Sea operators would have some form of instruction for operations with high sea states - wrong again! A comprehensive Flying Staff Instruction (FSI) was issued in October 2008, agreed by all three operators, but this was withdrawn after three days. Why, you may ask? Because the oil companies in Oil and Gas UK didn't like the restrictions it put on the operators when sea states increased! We, the pilots, were promised by our managements, that 'other guidelines' would be issued in due course. Three years later, in 2011, no such 'guidelines' existed. The only 'guidance' available was from BALPA and good old fashioned common sense - ie don't operate outside the aircraft's limitations!

So I'll ask you once again, what would have been the outcome of the Bond 88R ditching had it occured on 25 October 2011?

Stay safe everyone.

bondu
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Old 19th May 2012, 10:29
  #194 (permalink)  
 
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How else are we arm chair experts to pass our time? It is a rumour network, which is tantamount to a casual blether by medium of text.

Personally I'd like to nominate myself for shooting in the dark. Which field will yours be? Heckling from the bleachers?
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Old 19th May 2012, 13:31
  #195 (permalink)  
 
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Bondu,

There is risk to almost everything we do in life.

The Authorities have calculated the Risk factor of those kinds of failures that will put you into the oggin.

The Oil Companies and Operators have determined the trade off between Risk and Cost and have apparently decided the current mode of operation is worth the cost.

Their case is proved by the very fact that 88R did not happen in Sea States you describe.

The two Operators that flew were just as safe as the one that did not fly as it turned out.

As the chance of having to ditch is so insignificant....and the likelihood of having to do so in Sea States above the certification level of the Aircraft....why not operate over Sea States in excess of SS6, air temps at or below freezing, and water temps not much warmer?

If we write off a crew and a load of passengers now and then....they are paid for under the Cost-Benefit Analysis the Oil Company and Operator have done....are they not?
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Old 19th May 2012, 15:52
  #196 (permalink)  
 
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SASless,

You are absolutely correct, as usual! Just so long as the Cost-Benefit Analysis stays in the black, who really cares. I always wonder what the beancounters would decide if one of their own relatives was a regular passenger, or heaven forbid, if the beancounters actually had to fly themselves?

Just a silly question though: I wonder just how much the oil companies place on the loss of two pilots, up to 19 pax and of course an expensive EC225/S92/AW139 etc? Half a days profit: a full days profit? No doubt they will have it covered by some fancy insurance. Of course, their fancy expensive lawyers will argue that the decision rests with the helicopter operator not the oil company. And the operator will no doubt say that the pilots should have exercised their judgement and push any and all blame onto the crew.

Nothing changes!

bondu
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Old 20th May 2012, 07:07
  #197 (permalink)  
 
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Bondu,

I suspect that the Oil Company's insurance will not be involved at all. They have a contract with the operator and since the operator retains operational control of the helicopter, only the insurance of the operator will be involved.
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Old 20th May 2012, 11:20
  #198 (permalink)  
 
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Bondu

Remember, SS6 is not Limitation, it is only what the equipment has been certified to in a wave tank. The key issue is whether or not the heli will roll over, and this is not only related to wave height but also wavelength and in particularly whether the waves are breaking.

If the heli did roll over, the outcome might or might not have been worse.

Bearing in mind there is no such thing as Safe or Unsafe in aviation (merely shades of grey) it is surely down to probabilities. Probability of ditching in the first place is very low, probably of ditching in unsuitable sea conditions say 50 times less (ie let's say 7 days a year with high SS) so it is getting down to the levels of probability around which the fundamental design of the heli is based, eg the propensity of the rotor blades to remain attached etc.

HC
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Old 20th May 2012, 11:57
  #199 (permalink)  
 
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HC

I don't know if is the case but isn't the S92 limited to SS6 in the Flight Manual as opposed to the certification?
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Old 20th May 2012, 13:06
  #200 (permalink)  
 
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I don't know if is the case but isn't the S92 limited to SS6 in the Flight Manual as opposed to the certification?
No, it is not the case - there is nothing in the limitations section about sea state.
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