North Sea heli ditching: Oct 2012
Yes. Design Verification.
Joking might be excused under the banner of gallows humour in this particular instance given all are well, although in no small thanks to the pilots.
Fair play to the CAA but actually I'm not sure the terrain - hostile or not - cares too much when the gearbox internals are sh1tting themselves.
This is going to end up as a Harvard business school case study. Eurocopter have winged it since May in a vein attempt to avoid what is now the almost certain fact that they will need to say that a design, material, manufacturing (or combination) has caused issues. The failure of the Emergency lubrication system is a sideshow.
Beyond that the failure of the MGB in the 2009 crash of G-REDL suggests a more worrying attitude. In the case of REDL it was suggested in the AAIB report that the planet gear was lifed to 6600hrs in the AS332, 4400hrs in the EC225. I think I'm right in saying that the failure occured at around 3800hrs but then the manufacturer seeming to want to rely heavily on HUMS which whilst mandated what are the thresholds of the condition indicators before the operator is well over the line?
Two things seem to hold true. The manufacturer in the event of a failure seems to rely very heavily on the HUMS and whilst they don't suggest it is the primary method of detecting gearbox degradation thats exactly how it seems to be spun when a EC225 ends in the sea.
Beyond that as has already been said before an alarm is fine but without strict guidelines of what exactly means "no go" I'm not sure the alarm was anymore help in the case of REDL.
Last edited by Pittsextra; 25th Oct 2012 at 19:49.
Cyclic yes I know, but that tragic accident is nevertheless unrelated to this one from a technical point of view.
The problem with that is you are using tech to cover up flakey mechanicals and when the technical specialisms are such that the manufactuer knows more than the authority its not hard to see how they can cloud issues.
Its a very dangerous situation.
Or to make the reasoning more obvious: Do you think fixing the one issue will do anything to prevent what happened in the other case ?!.
HC says
"For the record, Bristow downloads the HUMS data at each return to base, and an aircraft is in not despatched until the HUMS data has been checked and found to be "green". That process takes less than 5 minutes".
(Could be 4 hours of data?)
If correct surely it is no beyond reason to mandate this, 5 minutes v £XXm seems a good return.
I presume the new data is run against legacy data, & anomaly's logged\displayed, it is still not clear why there is no way of presenting real time information even in crude form,by continuous data streaming over air.
Formula 1 seems to have a fair grip on what is happening within engines, gear box & hydraulic systems, G force, steering angles, throttle & some life science for driver +++
"For the record, Bristow downloads the HUMS data at each return to base, and an aircraft is in not despatched until the HUMS data has been checked and found to be "green". That process takes less than 5 minutes".
(Could be 4 hours of data?)
If correct surely it is no beyond reason to mandate this, 5 minutes v £XXm seems a good return.
I presume the new data is run against legacy data, & anomaly's logged\displayed, it is still not clear why there is no way of presenting real time information even in crude form,by continuous data streaming over air.
Formula 1 seems to have a fair grip on what is happening within engines, gear box & hydraulic systems, G force, steering angles, throttle & some life science for driver +++
Shoes pinch a bit when they are on the other foot don't they?
If the Cougar Crew had complied with the Checklist (as the Co-Pilot reminded the Captain at least twice)....what would the score have been?
The accident analysis clearly demonstrated a prompt controlled ditching would have prevented the Gearbox failure that caused the uncontrolled crash into the water that proved fatal.
In the North Sea events the crews DID follow the Checklist.....despite the temptation in one case of having land quit near and all turned out well. That they did because of a false report of a failure of the Emergency Lube system does not change the fact they ditched rather than continue to fly a machine with a suspected gearbox failure.
We cannot say that about the one that shed its rotor head can we....and do we really know what caused that one? We know what failed....but do we know with definity what caused that to happen?
Why is it we see the EC aircraft being limited to a HUMS download every three hours.....are the MGB's that susceptible to failures that such monitoring is necessary?
You are quite correct I have flown neither the 225 or the 92 and that allows me to be absolutely impartial in my evaluation of the two. I never worked for Sikorsky or EC...I have not been a Company Type Captain, have not been involved in making recommendations to Management about which aircraft to buy, and have had no involvement in formulating SOP's, writing Checklists, or anything like that for an Operator for either of the two aircraft.
Are you that free of bias?
Face it....EC has a problem every bit as serious as Sikorsky did. Like it or not....currently your favorite helicopter is grounded as being unsafe to fly in the Commercial Market.
I would suggest implying Bristow is bullet proof on this is just Whistling as you walk past the Graveyard.
The fact Bristow has not had one of these events does warrant examining to see what is being done different by your Engineering staff that might not be happening elsewhere....as there might just be something there worth duplicating by other Operators.
Yet....the absence of an event does not mean it cannot happen to Bristow.
S92 had a head start on catastrophe, now it is 225's turn to catch up a bit, but now that the fleet has effectively been grounded this problem will be fixed and without loss of life.
If the Cougar Crew had complied with the Checklist (as the Co-Pilot reminded the Captain at least twice)....what would the score have been?
The accident analysis clearly demonstrated a prompt controlled ditching would have prevented the Gearbox failure that caused the uncontrolled crash into the water that proved fatal.
In the North Sea events the crews DID follow the Checklist.....despite the temptation in one case of having land quit near and all turned out well. That they did because of a false report of a failure of the Emergency Lube system does not change the fact they ditched rather than continue to fly a machine with a suspected gearbox failure.
We cannot say that about the one that shed its rotor head can we....and do we really know what caused that one? We know what failed....but do we know with definity what caused that to happen?
Why is it we see the EC aircraft being limited to a HUMS download every three hours.....are the MGB's that susceptible to failures that such monitoring is necessary?
You are quite correct I have flown neither the 225 or the 92 and that allows me to be absolutely impartial in my evaluation of the two. I never worked for Sikorsky or EC...I have not been a Company Type Captain, have not been involved in making recommendations to Management about which aircraft to buy, and have had no involvement in formulating SOP's, writing Checklists, or anything like that for an Operator for either of the two aircraft.
Are you that free of bias?
Face it....EC has a problem every bit as serious as Sikorsky did. Like it or not....currently your favorite helicopter is grounded as being unsafe to fly in the Commercial Market.
I would suggest implying Bristow is bullet proof on this is just Whistling as you walk past the Graveyard.
The fact Bristow has not had one of these events does warrant examining to see what is being done different by your Engineering staff that might not be happening elsewhere....as there might just be something there worth duplicating by other Operators.
Yet....the absence of an event does not mean it cannot happen to Bristow.
Join Date: Nov 1998
Location: UK
Posts: 460
Likes: 0
Received 0 Likes
on
0 Posts
technically there does not seem to be a causal connection between the two 225 shaft failures on the one side and the 332 sun gear failure on the other side
Join Date: Jan 2001
Location: UK
Age: 71
Posts: 1,364
Likes: 0
Received 0 Likes
on
0 Posts
Congratulations to the CAA for having the balls to issue their Directive. 
When I read the EASA AD its logic and rationale seemed to have so many holes it looked like a Swiss cheese.
The CAA do not appear to be advertising their initiative by broadcasting it on their website on the pages that the media might check. It must be a difficult thing for them to do politically, in essence publically disagree with the all-powerful (but wrong) EASA bandwagon.
Cannot but wonder at the pressures that may be being applied. I wonder if the general media will catch-on to what is happening?
When I read the EASA AD its logic and rationale seemed to have so many holes it looked like a Swiss cheese.
The CAA do not appear to be advertising their initiative by broadcasting it on their website on the pages that the media might check. It must be a difficult thing for them to do politically, in essence publically disagree with the all-powerful (but wrong) EASA bandwagon.
Cannot but wonder at the pressures that may be being applied. I wonder if the general media will catch-on to what is happening?
Last edited by Helinut; 25th Oct 2012 at 23:18.
The BBC know about it:
Restrictions imposed on Super Puma helicopter
Restrictions imposed on Super Puma helicopter
The Civil Aviation Authority (CAA) has banned the use over sea of helicopters similar to one which ditched off Shetland.
The CAA order applies to all Super Puma EC225s and some AS332s, except those involved in "life-saving" operations.
The manufacturer has ordered extra safety checks in an attempt to prevent a repeat of the incident.
An air accident report on Monday's ditching said it was caused by a serious gearbox failure.
All 19 men on board the Super Puma EC 225 survived.
Continue reading the main story
“
Start Quote
I understand that Eurocopter has to rebuild confidence in our company. Two ditchings are two too many”
Derek Sharples
Eurocopter executive vice president
Eurocopter said gearboxes should be monitored more closely and at more regular intervals.
The French company said Monday's problem was similar to one which caused a helicopter to ditch in the North Sea in May.
It said all its efforts were now being devoted to fully understanding the root cause of the failure.
Eurocopter executive vice president Derek Sharples told the BBC Scotland news website: "I understand that Eurocopter has to rebuild confidence in our company.
"Eurocopter has issued a new set of measures to reassure operators, crew and passengers that the aircraft is safe to fly. With these measures we seek to eliminate any reoccurence.
"We understand these concerns and take them seriously. Two ditchings are two too many."
Investigators found a failure in the lubrication system of the helicopter which ditched near Fair Isle.
A special bulletin issued by the Air Accidents Investigation Branch (AAIB) said the main and standby oil pumps were not working.
Shaft crack
All those on board the Super Puma EC 225 were rescued safely after it ditched during a flight from Aberdeen to the West Phoenix rig, west of Shetland.The AAIB report suggests that the helicopter came close to being involved in a much more serious incident on Monday.
The bulletin said a 360 degree crack was found on the bevel gear vertical shaft of the helicopter.
This crack prevented the oil pump gears from being driven.
The AAIB said the European Aviation Safety Agency (EASA) and the manufacturer were urgently reviewing the effectiveness and scope of an airworthiness directive previously issued for this helicopter type.
Flights by other aircraft of the same type have been halted.
'Growing concern'
BBC Scotland has also learned that two North Sea search and rescue Super Pumas operated by BP have been restricted to "life-saving" operations only in the wake of the incident.
These are rescuing people from the water, and "life and death" medical evacuation cases.
BP said it was looking at bringing in Sikorsky aircraft to provide temporary cover while the industry examines the evidence from the CHC-operated Super Puma ditching.
Balpa, the union which represents professional pilots, said there was now "growing concern" amongst pilots and offshore workers.
'Saving lives'
Willie Wallace, regional industrial officer with the Unite union, said: "We clearly have a problem with the gearbox components on these particular helicopters.
"The manufacturer Eurocopter has ordered safety checks and said that 'two ditchings is two too many'.
"We agree. We cannot rely on luck to keep saving lives."
The crew of another Super Puma helicopter ditched in the North Sea in May after a gearbox failure.
All 14 passengers and crew involved in that incident, about 30 miles east of Aberdeen, were rescued.
A special meeting of the industry's helicopter safety group is due in Aberdeen on Thursday afternoon.
The CAA order applies to all Super Puma EC225s and some AS332s, except those involved in "life-saving" operations.
The manufacturer has ordered extra safety checks in an attempt to prevent a repeat of the incident.
An air accident report on Monday's ditching said it was caused by a serious gearbox failure.
All 19 men on board the Super Puma EC 225 survived.
Continue reading the main story
“
Start Quote
I understand that Eurocopter has to rebuild confidence in our company. Two ditchings are two too many”
Derek Sharples
Eurocopter executive vice president
Eurocopter said gearboxes should be monitored more closely and at more regular intervals.
The French company said Monday's problem was similar to one which caused a helicopter to ditch in the North Sea in May.
It said all its efforts were now being devoted to fully understanding the root cause of the failure.
Eurocopter executive vice president Derek Sharples told the BBC Scotland news website: "I understand that Eurocopter has to rebuild confidence in our company.
"Eurocopter has issued a new set of measures to reassure operators, crew and passengers that the aircraft is safe to fly. With these measures we seek to eliminate any reoccurence.
"We understand these concerns and take them seriously. Two ditchings are two too many."
Investigators found a failure in the lubrication system of the helicopter which ditched near Fair Isle.
A special bulletin issued by the Air Accidents Investigation Branch (AAIB) said the main and standby oil pumps were not working.
Shaft crack
All those on board the Super Puma EC 225 were rescued safely after it ditched during a flight from Aberdeen to the West Phoenix rig, west of Shetland.The AAIB report suggests that the helicopter came close to being involved in a much more serious incident on Monday.
The bulletin said a 360 degree crack was found on the bevel gear vertical shaft of the helicopter.
This crack prevented the oil pump gears from being driven.
The AAIB said the European Aviation Safety Agency (EASA) and the manufacturer were urgently reviewing the effectiveness and scope of an airworthiness directive previously issued for this helicopter type.
Flights by other aircraft of the same type have been halted.
'Growing concern'
BBC Scotland has also learned that two North Sea search and rescue Super Pumas operated by BP have been restricted to "life-saving" operations only in the wake of the incident.
These are rescuing people from the water, and "life and death" medical evacuation cases.
BP said it was looking at bringing in Sikorsky aircraft to provide temporary cover while the industry examines the evidence from the CHC-operated Super Puma ditching.
Balpa, the union which represents professional pilots, said there was now "growing concern" amongst pilots and offshore workers.
'Saving lives'
Willie Wallace, regional industrial officer with the Unite union, said: "We clearly have a problem with the gearbox components on these particular helicopters.
"The manufacturer Eurocopter has ordered safety checks and said that 'two ditchings is two too many'.
"We agree. We cannot rely on luck to keep saving lives."
The crew of another Super Puma helicopter ditched in the North Sea in May after a gearbox failure.
All 14 passengers and crew involved in that incident, about 30 miles east of Aberdeen, were rescued.
A special meeting of the industry's helicopter safety group is due in Aberdeen on Thursday afternoon.
Don't forget this Bristows Puma ditch
That no one knows the circumstances of.
http://www.pprune.org/rotorheads/486...ex-g-pumi.html
That no one knows the circumstances of.
http://www.pprune.org/rotorheads/486...ex-g-pumi.html
Last edited by lowfat; 26th Oct 2012 at 00:14.
Join Date: Mar 2007
Location: London
Posts: 198
Likes: 0
Received 0 Likes
on
0 Posts
I was a bit disappointed by the Eurocopter man on the telly last night saying that the EC225 is a very safe helicopter.
What do you expect him to say?
He has to say that to one and all, it's his priority!
Join Date: Dec 2003
Location: Aberdeen, UK
Age: 61
Posts: 46
Likes: 0
Received 0 Likes
on
0 Posts
Well done to the crew of CHCN on a job well done!
Lowfat
I believe that PUMI was an unplanned ditching of a perfectly serviceable helicopter due to poor handling.
No Gearbox issues, hence irrelevant in this discussion apart from the ditching aspect (which was not planned), and evacuation process...
similar to the Bond ETAP 'ditching'.
Lowfat
I believe that PUMI was an unplanned ditching of a perfectly serviceable helicopter due to poor handling.
No Gearbox issues, hence irrelevant in this discussion apart from the ditching aspect (which was not planned), and evacuation process...
similar to the Bond ETAP 'ditching'.
Last edited by Jetboxer; 26th Oct 2012 at 01:36.
Join Date: May 2012
Location: Aer
Posts: 431
Likes: 0
Received 0 Likes
on
0 Posts
The problem with effectively grounding the EC225, even with the EC enhanced monitoring is that there will have to be a very solid reason to rescind the grounding. Without some concrete assurances that this problem is somehow fixed (with a new shaft?) which could take a long time, the EC225 could be having a long rest. In this instance, I think that increased oversight would have been better than a grounding.
"Oversight" can only be maintained by the HUMS being downloaded within every 3 hours of TOTAL running time, airborne and non-airborne. However I don't believe that we should be flying again until the emlube is made not only 100% reliable, which it is, but that the problem of false warning of emlube failure gets convincingly sorted out.
IMHO the present shaft has to be replaced with the older type which used different processes and techniques to join the bevel gear to the shaft. That will obviously take a long time to achieve. The French told our bosses that it can't be done, but I don't understand why. It has to be done!
With these provisos, I'll feel comfortable to fly again while a replacement for the existing shaft is being produced and tested. However our passengers will understandably need a lot of convincing.
IMHO the present shaft has to be replaced with the older type which used different processes and techniques to join the bevel gear to the shaft. That will obviously take a long time to achieve. The French told our bosses that it can't be done, but I don't understand why. It has to be done!
With these provisos, I'll feel comfortable to fly again while a replacement for the existing shaft is being produced and tested. However our passengers will understandably need a lot of convincing.
Join Date: Nov 1998
Location: UK
Posts: 460
Likes: 0
Received 0 Likes
on
0 Posts
With these provisos, I'll feel comfortable to fly again while a replacement for the existing shaft is being produced and tested. However our passengers will understandably need a lot of convincing.
Join Date: May 2012
Location: Aer
Posts: 431
Likes: 0
Received 0 Likes
on
0 Posts
Pitts
Increased HUMS downloads as Colibri says, not much else can be done. The 3 hour downloads should be sufficient to show the beginnings of propagation if past experience is anything to go by.
Now that it is grounded, what action can be taken to rescind the grounding?
New shaft? Design, test, manufacture and install; 1 year?
If it is 1 year, there are not enough spare 332Ls with functioning MGBs or S-92s around to make up the deficit. The oil companies will be looking for a way to not continue to pay the operators, who won't be making enough revenue to pay the banks. How long before some jobs may have to go?
Increased HUMS downloads as Colibri says, not much else can be done. The 3 hour downloads should be sufficient to show the beginnings of propagation if past experience is anything to go by.
Now that it is grounded, what action can be taken to rescind the grounding?
New shaft? Design, test, manufacture and install; 1 year?
If it is 1 year, there are not enough spare 332Ls with functioning MGBs or S-92s around to make up the deficit. The oil companies will be looking for a way to not continue to pay the operators, who won't be making enough revenue to pay the banks. How long before some jobs may have to go?
This is what the passengers are being told/briefed:
G-CHCN ditching incident - Step Change in Safety
http://www.stepchangeinsafety.net/te...setFileID=1562
G-CHCN ditching incident - Step Change in Safety
http://www.stepchangeinsafety.net/te...setFileID=1562