HC,
Are you really saying you don't know if EC compares HUMS data across its fleet?

I am astounded if EC doesn't do this, as I am astounded that you think it might be (but not necessarily) just 'fanfare and glossy websites.'

I would think that this cross-fleet HUMS comparison is essential, and that you would applaud the effort. Instead, you mock it and (strangely) seem more concerned about protecting the honor of a favored manufacturer.

Matari, I am a pilot, not a HUMS engineer so no, I am not familiar with the detail of the processes between our company, other companies and EC with regard to HUMS data.

Perhaps you should re-read my post because I didn't mock it, just put a generic caveat on not necessarily being impressed by the glossy cover of a book.

There is clearly some benefit to fleet wide data awareness, but once the fleet pattern is established that becomes a diminishing return. I can certainly see it being of great benefit to a small operator who has 1 or 2 airframes and doesn't fly that much, but much less so for a high intensity operator of multiple airframes whose own internal data represents a pretty comprehensive fleet sample.

Don't forget that Bristow invented HUMS (and I played my own small part in that development) and it was probably over a decade before the OEMs grasped the ball (longer for Sikorsky) so we are used to doing our own things and in the past, being the world experts in the subject at a time when the OEMs didn't have a clue. I am just saying all that so you realise "where I am coming from"

Large fleet operators like Bristow have the ability to gather large amounts of data and develop specific maintenance programs based on their operating profiles and experience. They do not have the ability to look across the fleet at others.

That's where the OEMs can really help.

If Sikorsky is capturing, analyzing and making recommendations based on that fleet data, then good for them. If EC is not, I have to wonder why they aren't adopting the best practices of others.

Organizations change and evolve. Sikorsky (and EC, and Bell) may have been slow off the mark, but it seems that partnerships with operators do pay off for all.

So bravo for Sikorsky, however flashy may be their style. I just wonder why someone who I believe genuinely strives for safety improvements, hasn't even asked the question about what EC does (or doesn't do) with fleet ops data. Bristow has an opportunity to lead, and force changes at EC if needed. But when loyalty to a certain type or manufacturer trumps basic engineering inquiry, then all operators suffer.

Matari
 

You have to remember that OEMs were not only slow off the mark they were very anti. They faced the prospect of an operator telling them, for example, that a new gearbox was producing vibes detected by HUMS and they wanted it replaced under warranty. They would say "on your bike and a curse on your box of tricks'. As far as they were concerned the scope for serious warranty issues was so great they lobbied against HUMS so Bristow, with I believe some help from Shell Aircraft, put up the cash to develop it.

G.
.

Matari, perhaps you think I am omniscient? We have a HUMS Type Engineer whose job it is to look after this sort of thing. He works with SIK and EC and I am confident that if there was a gap in EC's process that was not in Sik's, he would have done something about it. But I don't need to be breathing down his neck to see if he is doing his job properly. I doubt you would expect other pilots to be intimate with all their company's engineering processes so I don't understand why you think I should be?

I am editing my post to say that I guess the truth of it is that I still suspect that all this global analysis of data lark is just so many words. Exactly what processes do SIK follow with all this data? Easy to put it in a sales brochure but what does it actually mean? Any fleet has refinements made to its HUMS systems in the light of experience, obviously having more data helps this happen quicker, but I wonder if the 92 has had more refinement than other fleets, how often do refinements occur now, with the fleet reaching middle age? Can you give me some actual examples where it has achieved something other OEMs did not? Or is it all just talking up what is a fairly straightforward system?

Geoffers, I agree completely and I think 'slow off the mark' was a bad choice of words.

An analogy might be the industrial gas turbine world, where the OEMs followed the same tack. Early on they simply produced engines to sell to customers, and provided minimal service with new parts. When the competition did something new, they followed. They had no 'P&L' to partner with operators. Some within the OEMs viewed outspoken operators as a nuisance at best.

It took really bright, creative and tough operators like Statoil, GDF Suez, Duke Energy, FP&L, ExxonMobil to force the OEMs to make changes. Things like Remote Monitoring and Diagnostics, hot section component repairs, extended life...all these were forced on the OEMs by operators determined to create value and improve reliability and safety of their equipment.

It is a fundamental difference in what the two cultures are trying to accomplish.

The OEMs want to produce safe, reliable, competitive products. Operators want to get the most out of those products, and make them safer and more cost effective within the constraints of their stakeholders and regulatory authorities. This requires collaboration, give and take, and above all, money. Smart OEMs see this, and change the way they do business.

I am only surprised, and we can leave it at this, that someone who opines on all sorts of engineering subjects seems indifferent to an apparent best engineering practice by an OEM who he constantly berates. Openness to new ideas, even if they come from 'Brand X', should be welcomed.

Global data gathering
 

If EC are so keen on gathering data to improve the safety of their own aircraft, as well as improving their own understanding of problems that are arising, why don't they offer AAD as a free service instead of charging quite a substantial sum per aircraft?
Some of the smaller operators are not keen to pay this amount, thus everybody is losing out!

Thread drift
 

Forgive me, but I thought this thread was titled "North Sea heli ditching" ..? We seem to have drifted off thread a little.

Matari - you persist in your line and ignore my question about the actual benefits - if any. Therefore, until you prove me wrong I will have to assume that you can't actually quantify the benefits. Perhaps you too are taken in by the glossy spiel?

ps can't help noticing that your profile says "sales manager". Does that tell us something?

Flyer - fair point but unfortunately everyone is in it for the money - the OEMs, the Operators, the Oil companies and even the pilots. Especially the oil companies (just for you!). Why should the OEMs give stuff away for free when the Operators and Oil Cos are making a profit (and the pilots are scraping a meagre living). I don't recall receiving any free petrol recently!

OMB - surely HUMS is a key issue in this ditching and for once, I don't see thread drift.

OMB....and you are trying to take in a completely different path yourself. Folks are quite happy with the discussion which is dealing with topics related to the ditching if you care to check it.

An old boss once had a sign on his wall that said: 'Nothing happens until somebody sells something.' Pretty accurate, if you think about it.

Back to HUMS: You never know what the data will say. The larger the data set, the better. How can that be bad?

I've seen OEM-captured data from a gas turbine on a North Sea platform, used to prevent a failure in a Petrobras gas turbine offshore Brazil. If Petrobras had not had access to OEM captured data, they never would have known about the pending failure.

Two large, capable engineering companies, connected only by the OEM. Everybody benefited. Again, why knock an OEM trying to do the right thing?

Yes, clearly nothing happened in the billions of years before capitalism was invented.

A well timed article here . So it's all about cutting costs/increasing profit, and not at all about safety. Our shareholders will like it, not so sure about our passengers and pilots!

Sikorsky's comparison of all S-92 HUMS data in the "glossy brochure" FMOC shows some very different data between companies who operate their S-92s differently.

The data is now being used to determine the provision of spare parts known to be used more often in some operating regimes. It can also be used, together with historical parts used data to adjust PBH rates to be operator specific.

AAD costs?
 

Flyer

What is the cost of GEs AAD?

FYI. Bell's commercial HUMS fleet management system monitors 150+ aircraft at no cost to the customers via an Internet based application. This system allows Bell product support to monitor fleet and individual aircraft health, allows operators to see their ships and the rest of the fleet(with all competitor specifics sanitized so no one knows who is who), and emails alerts to the specific operators.

The Sultan

Apologies for dragging this thread back a bit, but my experience with the S92 doesn't agree with HCs. Yes, Sikorsky issue a "toughbook" with each S92 to allow for remote monitoring and maintenance support, however a single computer can be used for HUMS download on numerous airframes. Maybe Bristow haven't realised this yet?

So I am getting the picture now, the centralised fleet monitoring is all about spares / PBH / increasing component lives. Nothing wrong with that of course -it's a good thing - but also nothing to do with safety.

VL that's interesting. We certainly have a networked laptop for each airframe in Scatsta, whether we realise we don't need that, I am not sure. Has it always been the case that a single PC can be used, or was this a development?

HC, your analysis is one sided and simplistic.

SAFETY was of course the initial priority for the FMOC when the S-92 was introduced as a new type. To impugn Sikorsky is, however, one of your characteristics, and one which belittles your 30+ years in the industry.

However, after 7+ years of operations, including one fatal which did not show on HUMS but we have discussed that one enough, (hopefully) other uses have become apparent. Actually, as much as increase component lives for some and decrease their costs, analysis has even reduced lives for those who thrash their aircraft hard.

Not impugning Sikorsky, merely pointing out that Matari's impugnment(?) of EC for not having the same type of centralised HUMS system ( if indeed that is the case) is correct only on commercial grounds, not on safety grounds.

HUMS - the future
 

We have to remember that when HUMS was 'invented' the designers said it would take 10 years to gather enough data to understand what the HUMS is telling the end-user. That would appear to be an underestimate on two counts. The first is the need to extend HUMS usage across the board to expand the spectrum of data accumulated from all types and all applications and the second is to find the tools capable of providing reliable analysis of such a vast quantity of data.

I suspect that the way ahead is to somehow get closer to the problem. Wouldn't it be great if you could implant vibe-sensors into the gear wheels and read the output directly. I wonder if any of the electronics boffins are working on such ideas.

The problems caused by harmonics in a structure with so many rotating components are horrendous and trying to second guess the failure mode is a kind of self defeating process given that identifying a failure mode means that you have put your finger on a weakness. Best answer = remove the weakness. The failure mode is therefore by definition the one that takes you by surprise.

Better sensors could be the way forward.

G. :ok:

Cost of GE AAD
 

Sultan. The last I heard was around $6K per aircraft - at least that is what one OEM is charging.

HC. Although I agree that everybody is in this for profit. However, on a legal stance - if an accident occurs and it is found that AAD was not being used, although everybody knows that AAD provides enhanced risk management, could the operator and/or OEM be held culpable?

Flyer, perhaps the operator could be found culpable in a civil case, but not the OEM since how the aircraft are operated and the approved maintenance programmes are not within their control. I am sure the OEM would be seen to be squeaky clean if they provided the technology but the operator discounted it on the basis of a reasonable cost.

Geoffers - you are right. It is those un-thought-of problems that catch everyone out. The thought-of ones are usually no problem!

HC....be careful.....you might break your arm patting yourself on the back like that!:=

??? I am a simple soul so you will have to explain that if you want me to understand it!

Using HUMS data sounds like a step in the right direction. Afterall, how were component retirement hours figured before? Several thousand hours of test flying, examining the parts and them sitting down in a commitee and more or less compromising on a figure. Then once those components went to their retirement hours, the parts were returned, examined and, after enough were looked at, another committee descision to ask for an extension?

Hopefully HUMS will be another useful tool, as long as it doesn't become the be all and end all in determining a components life.

Perfection on production is key.....
 

..... but is it achievable? Probably not. Sad to say that ours is one of the industries that demands the highest standards of manufacturing but it is far from perfect.

One possible step in the right direction is deal with the problems created by the way each OEM works within a silo that generates a terrible mindset that precludes things they have not seen before but have been seen in other types made by other people.

To what extent, I wonder do OEM's study and test the equipment made by their rivals? Are there any formal liaisons between OEMs on safety critical issues? Should there be? What can EASA do about it?

G. :ok:
.

It is very worthwhile to work hard at improving drivetrain HUMS technology used by the rotorcraft industry, and there are lots of engineers currently doing just that. But even the best HUMS in use today really only monitor for problems that are already occurring, and they have very little predictive capability.

We should also consider the nature of what occurred in this particular failure. Based on the published statements from Eurocopter, it sounds like there was a manufacturing/QA problem with the weld joint on the shaft:

"....As already indicated in the AAIB Special Bulletin S6/2012, the initial visual examination has identified a 360° circumferential crack on the bevel gear vertical shaft (which drives the two Main Gear Box (MGB) lubrication pumps), in the vicinity of the weld that joins two sections of the shaft....".

Eurocopter's use of welding for highly stressed components is actually very common in the aircraft industry. The process used is friction welding. It is a "solid state" joining process and produces joints of extremely high quality. Friction welding is used to save weight and material cost, primarily in situations where the cross section of the component has large changes, such as the given example of a short large diameter gear disc on the end of a long slender shaft.

However, getting good results from friction welding does require careful control of the process. The other factor that would seem to indicate there was a manufacturing issue is the shaft appears to have failed in a location that would not likely be highly stressed (and that's what makes it a good location for the weld joint).

Just all speculation on my part. But it's certainly an interesting topic of discussion!

HC - I can't be totally sure, but I don't think this is a recent development. It certainly has been an option for at least the last 5-6 years. My understanding was that if you didn't want to take the HUMS card to the groundstation (one PC), then you could take each aircraft's toughbook to the aircraft for analysis.

As an aside, the toughbook was also touted as a reference library containing electronic and up to date versions of the MM, IPC, etc that could be used "beside" the aircraft. I'm not sure if they are ever used this way?

AAD
 

Flyer,

Thanks, for the info. I assume the 6k is per aircraft per year.

The flip side of the AAD argument is that you are paying for it and something happens then the AAD provider should be held liable. In the recent incidences including the loss of rotor on the Puma the AAIB report indicated that AAD techniques provided no improvement in warning time. Actually if all chip detections had been reported to the crew there would have not been a crash.

The Sultan

HUMS and G-REDL, discuss.

Sultan
 

I meant to add - that's the cost per month per aircraft!

This is what EC concluded:-

Manufacturer’s analysis of G-REDL HUMS

The helicopter manufacturer was provided with a copy of the G-REDL HUMS database and the downloaded HUMS data card from 1 April 2009 operations. Their analysis was performed by two teams; the first being by their customer
technical support team which reviewed all CIs. They concluded that there was ‘nothing abnormal to report’.

Pitts - We have already discussed at great length the problem of using current HUMS technology to establish the health of planet gears in an epicyclic, I suggest you look back for that discussion which was only a month or so ago, rather than trying to re-start it.

HC - no the point I was making is that its irrelevant what data sharing exists or doesn't exist if the data isn't going to make a difference.

In the EC225 cases it alarmed and allowed a controlled ditch but HMES isn't in my view anything more than a "best efforts" and depends hugely on which component fails.

Of greater interest is the mechanical issues which I can't see being resolved anytime soon. Does anyone know what % EC225 sales are as a total of Eurocopter revenues??

I do not know what to make of this as yes 2 shafts failed and it got the treatment it deserved with all subject to 3hr download of HUMS and yes most grounded in the interest of aviation safety etc. I do find it sad as somebody nowhere involved in this market that the 225 is treated so harshly(correctly again?) and being replaced by models with problems too yet not as defined as a specific shaft failure as on the 225 so flying threw their issues? Are the unions as informed about the MGB cracking and now airframe cracking issues on the 92 or the tailboom issues on the 139 as they are of the obvious and clear issue of the post 2009 shaft with 2 failures on the 225 which has a clear solution? What if the next one is not a 225-and I hope there is no next one?

There is a huge argument between HC and the rest as to HUMS data and the usage there of with speculation on all sides towards what EC does. The facts have been stated about Sikorsy and Bell but has anyone actually established how euroarms work and what EC does or doesnt do with the data? It is a argument with facts from Sikorsky and Bell it seems and a assumption that EC does nothing despite having euroarms I think is the EC specific HUMS version? As said I do not know this market or am involved, just find it astonishing the arguments and sentiment!

Not a good time for EC I presume at all but so the industry goes and it seems that they at least have a clear target to fix and as per the B3e restrictions and issues with the TR bearings after no previous issues on the B3's it seems that maybe our thurst for power has caught up with our technology? People referred in this threat to older more reliable platforms than the 225, 332L2,S-92, AW 139 but then those were the times when we all demanded more power from the engines!?

Victor, I think one thing to bear in mind is that the algorithms, signal processing etc in the HUMS systems of all the OEMs is pretty much the same. The AAD process is a newer devlopment but as far as I am aware, it is not built in to any of the OEM's systems, rather it is a bolt-on provided by GE.

The system on the 225, by the way, is called M'ARMS.

You are of course absolutely right in that the 225 is the demon of the moment, but other types such as 139 and S92 have all had substantial technical problems in the past that grounded or nearly grounded them. I hope and expect that once this shaft issue is resolved, the EC225 will come back into favour, though a lesson has been learnt about not having all your eggs in 1 basket.

Thanks for the correction HC, I last dealt with a offshore EC many years ago and then the state of the art was the euroarms. It was a L2 and a very old L2. I just wonder if the 2 225 failues had more than 1 possible cause whether it would have been this easy to ground a fleet. It almost is so simple the cause that is so clear and the cure that it is easy to say ground until fixed whiilst most modern helos are flying threw issues but they are not as clearly defined so no clear demand to fix before we fly again etc! I am probably way of base but it seems that the obvious and simple is the problem here?

Given the process - or rather lack of - EC can not be surprised.

In the end, without wishing to sound smart after the event but where in the process have EC taken care of their brand and reputation in this pre-accident?

It all seems very "matey" and customer friendly without a thought that actually if something ends in a million pieces who did we put the trust in the hands of? After all the operator is a commercial entity and personally I don't think it is a great idea having alarms (in this case yellow, red) and then a woolley grey area beyond that.

You look at recent AAIB findings on EC machinary that has HUMS and there is a lack of consistancy with its usage and indeed understanding as to what and how it should be used.

I must say I have found this thread enlightening. I am an amateur pilot who works offshore. We normally fly out on 225's. I must say that a huge majority of the offshore work force has lost all confidence in this aircraft due to the events of late. I am glad to see it is held in such high regard by those who fly it and work on it. Our operator had not had any incidents as I believe they have excellent maintenance procedures.

We have received very little in the way of information as to what the problems actually are with the gearbox issues which only serves to enhance the fear of flying as a passenger in one.

If you are a pilot and not serious about maintenance ...
 

HC, I am amazed at your attitude regarding aircraft maintenance. Perhaps what you are saying is not how you actully go about your day to day business.

Maybe it was my military training, but I suggest to you that if you don't become personally familiar with what is behind keeping your bird in the air, you are setting yourself up to make some incorrect decisions on taking a bird up, or keeping one flying, or not keeping one flying. (This goes particularly for helicopters, who have more moving parts than fixed wing).

Professional pilot: not only do you need to know your aircraft inside and out, you need to know how it works, and what makes it work.

Nonsense. Chaging or fixing parts before they fail, and hence before they fail In Flight, has a bit to do with Flight Safety. Do you understand?

I mention this in part to me not being the only person who feels this way.

The US Army (operators of the world's largest helicopter fleet) is currently spending millions on a program to improve their Condition Based Maintenance posture. Their intent is to better ensure that parts that are not wearing out (or otherwise showing signs of impending failure) are left on wing and parts that do show those signs are removed in a timely fashion. It has everything to do with a combined set of factors: readiness, cost, and safety. They are all bound together.

Geoffers.
Amen, Deacon.
As I understand it, yes. But one still has to collect data and know what info aides a decision, and what is noise.
Well put. The fifty pound brains are working on it, but as you point out, it's one of those multi-variable problems that does not lend itself to quick, easy solutions.

Another note on HUMS in real life. (I hope we can all agree that HUMS, in its current form, is NOT a silver bullet by any means).

The US Navy has a number of HUMS-like programs for its helicopter fleet. The operators still run into the problem of identifying and rejecting false positives. It's an ongoing battle no matter who you are, in terms of fleet operation, maintenance, and management.

As Geoffers points out, it's a field with ample opportunity for improvement and development. It is my belief that in due course, HUMS programs and diagnostics will improve and make rotary wing ops both safer and more cost effective.

Tying this post back to the ditching event, the impression being left in some minds, if carelessly presented, might be that HUMS is an ironclad sort of system that allows for no fault or simple go/no go decisions.

That message should be squelched when found.

Of course, however in this case it is being used to increase component lives in order to decrease costs, not to improve safety. In fact reducing safety margins. Do you understand?

abzoilworker, I suppose I can't be surprised about your comments regarding the offshore workforce's confidence in the 225, but suffice it to say that all helicopters have their problem areas and, although the 225 is in the spotlight at the moment, the problem will be resolved. I agree that the lack of clear information leads to crewroom / canteen gossip which usually causes a downward spiral of confidence and the catastrophisation of the situation. That is just human nature, regardless of whether there is sound science behind it.