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Old 19th May 2017, 11:05   #1801 (permalink)
 
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Concentric

This does appear to be a plausible mechanism to explain the crack propagation in the gears. It cannot be the sole reason because a crack has to be initiated by some other event or process first, but once that opening or pit is created it would seem that eventual failure is inevitable. Every compression cycle would be the equivalent of driving an incompressible hydraulic wedge deeper into the material. As the process continues the hardness of the surface layer would assist in driving the crack propagation deeper into the softer underlying material.
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Old 19th May 2017, 11:37   #1802 (permalink)
 
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Gouli,

Indeed, the crack has to be initiated somehow and it appears from the report that it was from one of a series of micro-pits 15mm - 16mm from the top face of the bearing, so all of them slightly below the line of maximum Hertzian pressure at 14mm but where sliding contact might begin. That it was not one isolated micro-pit (a rare occurrence in itself) but one of several in a row is, I think, a clue as to how it came to exist. Those other micro-pits should give the metallurgists something to analyse.
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Old 13th Jun 2017, 21:07   #1803 (permalink)
 
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Plan B

Dear All
As we are waiting for the final report , and modification / inspection-cycle or change of manufacturer of certain parts: How many ac are effected ( Norway and UK)
And what have the operators done.
I have followed this thread with great interest , but have little grasp of the local , regional and worldwide consequences for the SuperPuma.

I do compare this with the rudderhardover that B737 did suffer long time ago.
It is do or die, but they found the likely cause and did a good fix!

Anyway, I understand the Norwegian NTSB are mostly respected for not bowing to undue external pressure.

At the end of the day: we can never have main rotors depart without warning like this again. Your part of aviation is inherently more challenging than airliner ops is , never mind the wings going AWOL.

Regards
Cpt B
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Old 1st Jul 2017, 09:34   #1804 (permalink)
 
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There was a couple of low key press releases by Airbus claiming the 225 will be returning to service soon.
https://www.flightglobal.com/news/articles/h225-helicopter-to-return-to-full-flight-status-soo-438783/

https://www.flightglobal.com/news/articles/uk-caa-sees-no-prospect-of-quick-return-for-grounded-438857/

This survey has appeared on one of the offshore sites.
http://www.airbushelicopterssurvey.com/
I dont think they realise how things have moved on
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Old 1st Jul 2017, 09:38   #1805 (permalink)
 
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Originally Posted by S92PAX View Post
I dont think they realise how things have moved on
Not exactly sure to understand what you mean here?
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Old 1st Jul 2017, 09:46   #1806 (permalink)
 
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I meant the 225 has been replaced and even if was introduced again the strength of feeling against flying in it is too great to overcome.
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Old 1st Jul 2017, 10:07   #1807 (permalink)
 
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Interesting articles. Regardless of one's individual opinion, the market doesn't really need the H225 at the moment. S-92s took up most of the slack and the Super Mediums are taking slots where they fit which will free up more S-92s to use where a heavy type is definitely required.
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Old 1st Jul 2017, 18:35   #1808 (permalink)
 
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TM is probably right about the current market needs.

Super Puma on the front page of the P&J again today. Plenty of opinions inside from people who know less than nothing about helicopters. Plenty of mistakes as well. (H255?!)
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Old 2nd Jul 2017, 23:09   #1809 (permalink)
 
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https://www.energyvoice.com/oilandga...rth-sea-skies/

Quote:
The spokesman said: “Airbus Helicopters has launched an online helicopter users’ survey.

“We are keen to hear directly from these users, mainly pilots and passengers, regarding their thoughts on helicopter features in general and the H225 in particular.

“This broad and valuable feedback is key to helping us address the concerns, priorities and requirements of those who use our helicopters on a daily basis.”
I wonder if they will share the results?
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Old 3rd Jul 2017, 11:23   #1810 (permalink)
 
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https://www.energyvoice.com/oilandga...rth-sea-skies/



I wonder if they will share the results?
I am sure that if a lot of E&P workers were to reply positively then they would.

More relevant is that the industry in the North Sea changed. Operators/customers increased the use of medium types and many more of these have been introduced. I can see the use of the S92s being reduced and the mediums taking up a bigger share of the market.

What the Bergen crash seems to have been is a catalyst for this change.

AH have a decision to take on their new large helicopter, the mock-up shown in Paris asking as many questions as it answered. This survey is likely to have been issued partly to tell them how closely it can resemble the 225 and still sell, as evolution rather than revolution is always the preferred design approach.

Returning the 225 to the North Sea in any significant quantity has always seemed unrealistic in my opinion - but when you have a lot of history and personal in investment in a product it is very hard to let go.

Last edited by birmingham; 3rd Jul 2017 at 11:56.
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Old 4th Jul 2017, 11:32   #1811 (permalink)
 
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I think a number of the operators are able to claim compensation from Airbus during the time the 225 is grounded - much of this income is then ploughed into medium types, with the remainder kept for other operational costs or, in the rare case given the poor state of the industry, profit. When they are no longer able to make a claim (if/when the 225 is cleared to fly again), they may have to revert back to using it purely for financial reasons. I think there is still a market for them there - the S92 is not without its own problems.
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Old 4th Jul 2017, 12:45   #1812 (permalink)
 
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While the oil price is in this current regime, there will be increasing moves away from heavies as for most oil companies, the main driver in all decisions is price. The costs of heavies make them uneconomic in comparison. The H225 is dead in the water commercially unless Airbus can cut their hourly DOC/ PBH dramatically and the leasing companies accept the hit and drop the lease rates dramatically. Even then, it's reputation is still in the toilet.

It goes back to the Air Advisers and C&P people at the oil companies - who is going to sign up their workers to an H225 contract? Answer - no one for the foreseeable future.

IMHO AH would be better off focusing on selling what they have to militaries and spending their time and money creating something else.
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Old 5th Jul 2017, 12:23   #1813 (permalink)
 
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It goes back to the Air Advisers and C&P people at the oil companies - who is going to sign up their workers to an H225 contract? Answer - no one for the foreseeable future.

Agreed - if you don't work in E&P it is easy to miss the commercial point. All the major helicopter people were suffering long before Bergen

CGG a major services company baked by the French state filed for bankruptcy recently, their revenues are only 30% of what they where before the slump. Many other service companies are 50% or less. So the problems go beyond the 225 or helicopters. Since Bergen the North Sea has moved to the S92 and mid-sized types but there have been no significant new orders for new builds announced to meet the gap other than a couple to be used for SAR contracts for Statoil. It has been about redeploying existing machines.

Even if this hadn't happened there would have been a big downturn in demand for helicopters. The timing of the Bergen incident was such that it was probably the final nail in the coffin. The 225 and other Pumas certainly have some sort of future but there are few signs in the O&G market that it will be needed here.

Last edited by birmingham; 5th Jul 2017 at 12:35.
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Old 5th Jul 2017, 13:30   #1814 (permalink)
 
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when you see that AW is dumping 169 at high 6 mil you know wheres the market.

But OEMs somehow come up with the same conclusion that the market will bounce back in foreseeable future. And they are burning cash flow to flood the market when low so they are "prepared for the market comes back".
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Old 5th Jul 2017, 16:48   #1815 (permalink)
 
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Originally Posted by Mee3 View Post
when you see that AW is dumping 169 at high 6 mil you know wheres the market.

But OEMs somehow come up with the same conclusion that the market will bounce back in foreseeable future. And they are burning cash flow to flood the market when low so they are "prepared for the market comes back".
The problem this time is fracking and to a certain extent renewables. As soon as the price moves up the US completes more wells. Renewables provide a small but no longer insignificant share - this will increase. Supply will not be an issue for some years,if at all. The N/S will still survive but will be leaner - with smaller operators and a greatly reduced cost base. Statoil will hang on in there; there have even been new discoveries - one very significant. But increasingly it will be the preserve of specialists. - but there will be no return to the status quo of mega platforms and mass transit.

It will be a very different North Sea with different transport needs.

Last edited by birmingham; 5th Jul 2017 at 17:00.
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