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Old 17th Apr 2009, 09:48
  #81 (permalink)  
 
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HC,

A little bit harsh - particularly as Bristow has been part of the ongoing improvement project with GE. It proceeds slowly (more slowly than we would prefer) but that is a function, not of money, but of the scarcity of personnel to 'manage' and 'work' on these research and development systems. How much return do you think that GE (or others) could make on the sale of any such system?

Remember the dream with this particular development system, that it could sit as an anomaly detection tool above any HUMS (or any other data rich) system and provide a uniform interface.

Before this accident, there was no imperative to speed up development in any area. Let us see what the AAIB/EC/GE analysis of the HUMS data provides in this case - it might result in a clear focus that will provide an acceleration and concentration of effort. The recommendations might well be in the HF area but, until we see the report, we cannot possibly know.

maxwelg2,

It's OK to make these statements but you need to understand that there are dangers associated with physical intervention - you need to remember what brought you into this forum in the first place. There is need for interpretation in all but the simplest systems; we need all the tools in the toolkit and all appropriately utilised (as the Sultan previously indicated in his remarks about mag-plugs) but we also need qualified personnel.

Some years ago (at the last HHMAG meeting attended), the FAA indicated that they intended to spend several millions on HUMS implementation; I for one have not yet seen the fruit of that investment. Has anyone else?

Jim
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Old 17th Apr 2009, 10:52
  #82 (permalink)  

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I would ask why there aren't enough people with the knowledge to utilise HUMS to its full advantage.

Perhaps the government could do more to encourage young people to take up engineering. They are talking about apprenticeships - the aviation industry could gain a lot from an increase in the numbers of properly trained and sufficiently paid specialists.

Perhaps manadatory action is required.
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Old 17th Apr 2009, 10:54
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Thank you all for your replys to my post , I feel that there are 2 ways forward the single track, " we know what is best" or the one "we are all in this together", some take one route, others try and look at the overall picture.
HC you are correct I have never seen a HUMS ground station or a M'ARMS station, not being a professional helicopter pilot this thread is only of academic interest to me, other than hoping that discussion will push forward safety, but I have looked at a fair amount of telemetry information from in car systems, still don't understand all of it, would totally agree it is a specialised field, but big trends are noticeable, as in 192. why was it not acted upon, I would have walked away if someone could not have given me a very sound reason for jump in reading.
If there is a dodgy graph, I would like to have it explained to my satisfaction.
maxwelg2
We are thinking along the same lines, I feel that physical intervention produces its own dangers, so the best of both worlds is the way forward.
JimL
Thanks for your offer will PM you, don't know how much will sink in but will try to get my head around as much as possible.
I appreciate the 5 tonnes and over, presumably due to cost , complexity & commercial pressure, perhaps with further work and a larger user base, the cost should come down allowing lighter helicopters to utilise maybe a cut down version of the technology,
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Old 17th Apr 2009, 12:30
  #84 (permalink)  
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JimL,

Some years ago (at the last HHMAG meeting attended), the FAA indicated that they intended to spend several millions on HUMS implementation; I for one have not yet seen the fruit of that investment. Has anyone else?
As you well know.....promises from government are not exactly something would care to bet the house on especially coming from the FAA whose concept of urgency comes closer to being a Slug Race than a Hare Chase.

Unless they put a time certain in the promise and then followed it up by hundreds of PR fete's.....then expecting the usual delays and over runs.....don't ever look forward to seeing something from that bunch.

Their bureaucratic chain is advanced of the Italian style and they had an 800 year head start on the FAA.
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Old 17th Apr 2009, 12:43
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Jim

Your point
Before this accident, there was no imperative to speed up development in any area
sums up my point really well - but do we really have to rely on people dying to trigger a move to improve? We all knew that HUMS had not moved on from its infancy - Smiths/GE at least tried to do something but not many were listening.

You are right that its perhaps not primarily a function of money, its probably primarily a function of interest from the industry. Someone (a body or an individual) has to "own" a project like that and push it along, otherwise it stagnates with or without money.

HC
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Old 17th Apr 2009, 13:37
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HC,

As with all of these systems; they work better when they are someone's hobby-horse - as I have said to you many times.
You are right that its perhaps not primarily a function of money, its probably primarily a function of interest from the industry. Someone (a body or an individual) has to "own" a project like that and push it along, otherwise it stagnates with or without money.
As I said in an earlier post, the body that used to provide the focus was the Helicopter HUMS Management Group (HHMAG); when EASA became the legally competent body for airworthiness, the CAA could not progress the issue any more, and no longer had a budget for arranging, facilitating and hosting the meetings. Virtually the last act of the HHMAG was an attempt to ensure that the UK/Norway Requirement was adopted by EASA.

EASA neither adopted the group (the excuse was that their methodology did not extend to standing committees; hence the disbandment, as well, of all JAA committees - before taking advantage of their knowledge for the production of OPS Regs), nor did they take over the role of continuing to require HUMS. As I also indicated earlier (without any comment on PPRune), the EASA Ops Proposal does not contain a requirement for HUMS - which puts it out of compliance with an ICAO Recommended Practice. Without a State invoking Article 14 of the Basic Requirements, HUMS will cease to be a requirement at the time that EASA OPS comes into force.

Progress indeed!

Jim
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Old 17th Apr 2009, 13:42
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Another AAIB message...

Super Puma crash: Air Accidents Investigation Branch issues another compulsory inspection notice

Whether it's improvement to HUMS, iHUMS, or to the system for interpreting the data or whatever, something has to happen.
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Old 17th Apr 2009, 13:58
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EASA Airworthiness Directives Publishing Tool
EAD issues by EASA
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Old 17th Apr 2009, 14:05
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Oilandgasman, that's the original.

The new release, so far published only by the AAIB (soon EASA I expect) is not just about mag plugs, it's is about taking the epicyclic of every Super Puma apart and looking for something we don't know about.
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Old 17th Apr 2009, 14:26
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Hello. A few of my thoughts on HUMS for my first post.

Health and Usage Monitoring Systems are advisory, not executive. I can’t really see and alternative whilst HUM is an inexact science; and it is still far from being anything more than that. It certainly helps though, and I think most of those involved in RW (and indeed FW) engineering would agree that it currently makes flying safer, and in time will make it much safer. And cheaper – it’s on the path to CBM.

Meanwhile, it is immature technology and there are problems. Rotorcraft are hostile environments for delicate diagnostic systems, and HUMS are rarely 100% serviceable. It has to be working and someone has to look at, and understand, what it is saying for it to give protection. That person has to recognise the difference between ‘no exceedences’ and an unserviceable system. They should know that alert levels are statistical probabilities, not engineering/operating limits (unless actual fault data exists – the same fault shouldn’t be missed twice). They have to understand that alert levels will be different on similar aircraft with different HUMS and that the confidence levels in those alerts will vary, as will the criticality attached to the many cautions that their HUMS will provide.

Developments (like those at Chandlers Ford) in data mining, and possibly neural networks, to provide more accurate fault indications are particularly exciting and, from what I have seen, are very promising (google ProDAPS). However, I still think we are a few years away from allowing a vibration based diagnostic computer system to ground our aircraft without recourse to a well trained and HUMS educated engineering human brain.
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Old 17th Apr 2009, 15:03
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Short finals, yes you are of course correct. Have rechecked EASA and there is nothing new there at the moment. But the inspection work you have mentioned is being reported in the media with a 7 day time limit. I wish you all well with this task.
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Old 17th Apr 2009, 15:11
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shortfinals said
The new release, so far published only by the AAIB (soon EASA I expect) is not just about mag plugs, it's is about taking the epicyclic off every Super Puma apart and looking for something we don't know about.
Is this necessarily the case or could it be a boroscope inspection?
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Old 17th Apr 2009, 15:47
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Athough we have already seen a drawing of the MGB, this URL brings up a presentation which has (on slide 20) the drive train of the AS 332 with the superimposed EUROHUMS sensors indicated.

http://www.luftfartstilsynet.no/mult...eros_2084a.ppt

Jim
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Old 17th Apr 2009, 18:19
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Air Accidents Investigation: Initial Report 2 - Super Puma accident
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Old 17th Apr 2009, 19:37
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Helicopters grounded for 48 Hours

Posted on other thread relating to the Bond accident. Full article at BBC NEWS | Scotland | North East/N Isles | Helicopters grounded for 48 hours
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Old 17th Apr 2009, 22:47
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This may be a stupid question, but why is the AS332L1 not included in the MGB increased inspection requirements? Different design or based on lower power/load requirements?

The GE PowerPoint on ProDAPS was an interesting read. Many areas to be improved e.g. re-tuning sensor baseline data post-maintenance to account for revised quiescent harmonics etc.

JimL, I appreciate your point on the less invasive inspections the better, but in this specific case there does not appear to be any other choice until the root cause failure mode is determined. The only good thing that comes out of these tragedies is increased awareness and focus on preventative actions.

Has anyone considered a possible manufacturing issue with the gears on this specific MGB batch? I would expect QA/QC to be very tight, but will boroscope inspections be enough or will the gears require x-ray etc. to determine serviceability?
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Old 18th Apr 2009, 02:12
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Has anyone considered a possible manufacturing issue with the gears on this specific MGB batch
I'm sure a lot of people have - I certainly have.

A few years ago, in my previous company, a Bell-212 had a blade grip failure on a 1200 hour rotor head. Fortunately for the crew they were about 75 ft during the landing phase onshore, and 'got away with it,' though I think the underwear were written off! The point being that a vey old, established and proven design was the victim of poor manufacturing QA, and the head contained latent stresses which eventually resulted in the lower tang completely shearing accross its width.
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Old 18th Apr 2009, 05:16
  #98 (permalink)  
 
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This may be a stupid question, but why is the AS332L1 not included in the MGB increased inspection requirements? Different design or based on lower power/load requirements?

I’m told the gears in both the A332L2 and EC225LP are subject to increased hardening during the manufacturing process, I suspect as a result of increased torque levels.

I'm also told some of the Dauphins require repetitive boroscope inspections of the internal gearbox areas, but due to the seriousness of this inspection, I would be surprised if boroscoping alone would satisfy the level of inspection required by the Airworthiness Authorities.
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