North Sea Helicopter ditching 10th May 2012
HC....if the aircraft rolls over with people inside....the outcome is definitely going to be worse than if it stays upright. There might not be fatalities...but the stress and exposure would cause harm to the occupants.
A controlled ditching....and loading of the rafts directly from the cabin beats hell out of the thing going upside down, cabin filling with water, occupants escaping from underwater, then having to enter the rafts (if at all possible) from the water.
Bondu's point about considering Sea State and Environmental conditions as a limitation to Offshore Flights bears consideration.
There is not a single scheduled Offshore Flight that must be flown when scheduled.....every single one of them could be delayed or cancelled till conditions improve.
When does "inconvenience" trump "Safety"......that is the question that needs to be argued.....not "probability"!
A controlled ditching....and loading of the rafts directly from the cabin beats hell out of the thing going upside down, cabin filling with water, occupants escaping from underwater, then having to enter the rafts (if at all possible) from the water.
Bondu's point about considering Sea State and Environmental conditions as a limitation to Offshore Flights bears consideration.
There is not a single scheduled Offshore Flight that must be flown when scheduled.....every single one of them could be delayed or cancelled till conditions improve.
When does "inconvenience" trump "Safety"......that is the question that needs to be argued.....not "probability"!
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The question then becomes "who decides." The operators? The oil companies? The government?
Very doubtful the oil companies will - costs versus probabilities = costs win. Operators, unless they all get together and put their foot down - what's the probablity of that? - won't. As for the government regulating it, undoubtedly the first question would be - if we restrict helicopters from flying over let's say a sea state 6, what about commercial airliners? We all know what the answer to that question would be.
Very doubtful the oil companies will - costs versus probabilities = costs win. Operators, unless they all get together and put their foot down - what's the probablity of that? - won't. As for the government regulating it, undoubtedly the first question would be - if we restrict helicopters from flying over let's say a sea state 6, what about commercial airliners? We all know what the answer to that question would be.
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Cyclic
Some good did come out of Cougar 491, one area was discussions wrt. the limitation on sea state, especially over here where we have a much higher number of annual sea state days > SS6 criteria in comparison to other offshore flight operational areas.
Although all our regular S92s have been upgraded to SS6, the decision on acceptable flying conditions is to my knowledge made by Cougar based on mutual agreement with the operators (see Q42 in the attached Q&A link below). There are different limits based on each operator/installation type. The common denominator is 6 metres, no one over here will officially fly regular operations in that and/or wind speeds > 55 knots. Visibility is our other big issue over here, we have a lot of fog days.
http://www.cbc.ca/news/pdf/nl-helico...y-20090512.pdf
Bond 88R could indeed have been a much different story via multiple scenarios. Having not flown with Bond in many years I do not know what type of HUEBA is used if any, last I recall is the Shark rebreather but they may have moved on to the Airpocket Plus, either one I know from personal experience are IMHO inferior to the HUEBA, e.g. my last OPITO refresher was done in Malaysia last year where they make you do 5 HUET exercises, the last one being deploy Airpocket Plus underwater upside down, knock out window/door and egress. Add in cold water shock etc. and the statistics tell us that maybe only 50% of occupants will manage to egress an inverted helo.
Safe flying
Max
Some good did come out of Cougar 491, one area was discussions wrt. the limitation on sea state, especially over here where we have a much higher number of annual sea state days > SS6 criteria in comparison to other offshore flight operational areas.
Although all our regular S92s have been upgraded to SS6, the decision on acceptable flying conditions is to my knowledge made by Cougar based on mutual agreement with the operators (see Q42 in the attached Q&A link below). There are different limits based on each operator/installation type. The common denominator is 6 metres, no one over here will officially fly regular operations in that and/or wind speeds > 55 knots. Visibility is our other big issue over here, we have a lot of fog days.
http://www.cbc.ca/news/pdf/nl-helico...y-20090512.pdf
Bond 88R could indeed have been a much different story via multiple scenarios. Having not flown with Bond in many years I do not know what type of HUEBA is used if any, last I recall is the Shark rebreather but they may have moved on to the Airpocket Plus, either one I know from personal experience are IMHO inferior to the HUEBA, e.g. my last OPITO refresher was done in Malaysia last year where they make you do 5 HUET exercises, the last one being deploy Airpocket Plus underwater upside down, knock out window/door and egress. Add in cold water shock etc. and the statistics tell us that maybe only 50% of occupants will manage to egress an inverted helo.
Safe flying
Max
Hmm...probabilities. The probability of me having an engine failure in my EC135 during a flight are extremely remote(has there ever been one?). The probability of me having one during the few minutes during take off and landing are even less. The probability of me having one during the few seconds it takes to accelerate to single engine fly away speed during take off are infinitesimal.
However, I'm still required to fly the Cat A/Class 1 profiles.
As the probabilities are so small, need I bother?
However, I'm still required to fly the Cat A/Class 1 profiles.
As the probabilities are so small, need I bother?
SAS- by outcome I mean of course long term injury, death etc. and whilst this obviously becomes more probable, it would by no means be a certainty bearing in mind the extensive training and safety gear.
You are of course right, no flights HAVE to be conducted. In fact helis are intrinsically dangerous and it would be far safer to keep them in the hangar. In fact sitting on an enormous pocket of pressurised and explosive oil and gas, whilst probing it with a long steel drill is even worse. Best we go back to horse power, though do mind those hooves, they are quite dangerous.
Or to put it another way, Oil and gas industry including transport is a calculated risk. The calculations of risk should be based on science and not the fear of seeing big waves underneath you.
You are of course right, no flights HAVE to be conducted. In fact helis are intrinsically dangerous and it would be far safer to keep them in the hangar. In fact sitting on an enormous pocket of pressurised and explosive oil and gas, whilst probing it with a long steel drill is even worse. Best we go back to horse power, though do mind those hooves, they are quite dangerous.
Or to put it another way, Oil and gas industry including transport is a calculated risk. The calculations of risk should be based on science and not the fear of seeing big waves underneath you.
Last edited by HeliComparator; 20th May 2012 at 20:18.
MG - I am inclined to agree. Aviation regulation is obsessed with engine failure training when it is not a significant cause of multi engine heli accidens. It is historical from when piston power was the order of the day, and the authorities have not moved on because they are using emotion rather than hard facts to decide what is important.
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Helicomparator - you're right the assessment should be based upon the risks.
Unfortunately the risks associated with probing a high pressure reservoir, getting the stuff onboard, separating it and stuffing it down a pipe are on a well designed installation (there are a few) pretty close in round terms to the risks of getting to and from it for the people who work there.
For the pilots who fly them to and from the risks are actually significantly higher.....
For risks I'm talking about the individuals risk of death per annum, whilst undertaking their normal rotas.
For Mighty Gem - the chances of an engine failure during that critical period of flight are actually more of less equal to the rest of the entire flight (if it is under an hour). Big power changes are very likely to cause issues. Hence the need to fly profiles which offer a chance of recovery.
The major disappointment for me is that all of the 'newer' designs which are used offshore in the UK have had a variety of issues - which frankly should not have occured. From my personal perspective if you certify a helicopter on the basis of 10-9 failures per hour and it promptly fails then the certification should be pulled. For the 332 and 225 failures - I despair - designing reliable transmissions after all this time should not be so hard....
Unfortunately the risks associated with probing a high pressure reservoir, getting the stuff onboard, separating it and stuffing it down a pipe are on a well designed installation (there are a few) pretty close in round terms to the risks of getting to and from it for the people who work there.
For the pilots who fly them to and from the risks are actually significantly higher.....
For risks I'm talking about the individuals risk of death per annum, whilst undertaking their normal rotas.
For Mighty Gem - the chances of an engine failure during that critical period of flight are actually more of less equal to the rest of the entire flight (if it is under an hour). Big power changes are very likely to cause issues. Hence the need to fly profiles which offer a chance of recovery.
The major disappointment for me is that all of the 'newer' designs which are used offshore in the UK have had a variety of issues - which frankly should not have occured. From my personal perspective if you certify a helicopter on the basis of 10-9 failures per hour and it promptly fails then the certification should be pulled. For the 332 and 225 failures - I despair - designing reliable transmissions after all this time should not be so hard....
Avoid imitations
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For the 332 and 225 failures - I despair - designing reliable transmissions after all this time should not be so hard....
Gasax - not sure you are right about the levels of risk far more people have died whilst offshore than whilst in transit by helicopter. But when someone falls off a rig, is asphyxiated etc it is just another industrial accident. Only when an installation turns into an inferno with associated good photo opportunities and multiple deaths does the level of public interest reach that occurring when a heli ditches and everyone is fine.
On the subject of design, I firmly believe that the certification system is mostly to blame. There are such huge hurdles to be overcome to achieve certification of new bits, that manufacturers prefer to limp on with old designs when they can. When they can't, rather than designing a new system from scratch, they will design a bolt-on patch to allow the deficiencies to be lived with.
Of course these great certification hurdles, once overcome, in no way guarantees a safe product as is routinely demonstrated. And don't get me started on the effectiveness of software certification - it is a joke!
Certification is nothing more than a block to progress and product improvement. Discuss!
Regarding your last para, if that were done there would be nothing left flying and it would be the rowing boat offshore for you!
HC
On the subject of design, I firmly believe that the certification system is mostly to blame. There are such huge hurdles to be overcome to achieve certification of new bits, that manufacturers prefer to limp on with old designs when they can. When they can't, rather than designing a new system from scratch, they will design a bolt-on patch to allow the deficiencies to be lived with.
Of course these great certification hurdles, once overcome, in no way guarantees a safe product as is routinely demonstrated. And don't get me started on the effectiveness of software certification - it is a joke!
Certification is nothing more than a block to progress and product improvement. Discuss!
Regarding your last para, if that were done there would be nothing left flying and it would be the rowing boat offshore for you!
HC
Last edited by HeliComparator; 21st May 2012 at 10:03.
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HC - this is partly how I earn a living - the numbers for helicopter transport are that bad....
One would have hoped that defect tolerant design codes would have lead to an improvement - but they have not - at least in the present incarnation. I'm not sure the certification inself is the real reason. For instance JAR approvals for a new engine are quite modest - but of course the certification process and approvals engineers can have a huge influence in terms of 'opinion engineering', drawing things out by insisting of often irrelevent justifications - and that leads to manufacturers doing everything possible to avoid the certification process. Hence the re-treading of earlier 'successful' designs with numerous mods.
Shytorque -- yes the information to date does suggest a QC issue - but underlying that are design decisions - this is a 'low duty' shaft with appropriate levels of design detailing. Titanium studs would be another. At the end of the day it all rolls up into an overall incident rate.
One would have hoped that defect tolerant design codes would have lead to an improvement - but they have not - at least in the present incarnation. I'm not sure the certification inself is the real reason. For instance JAR approvals for a new engine are quite modest - but of course the certification process and approvals engineers can have a huge influence in terms of 'opinion engineering', drawing things out by insisting of often irrelevent justifications - and that leads to manufacturers doing everything possible to avoid the certification process. Hence the re-treading of earlier 'successful' designs with numerous mods.
Shytorque -- yes the information to date does suggest a QC issue - but underlying that are design decisions - this is a 'low duty' shaft with appropriate levels of design detailing. Titanium studs would be another. At the end of the day it all rolls up into an overall incident rate.
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HC:
You are quite correct to point out that wave height alone is not sufficient. The wavelength and period, leading to the steepness of the waves are just as important, if not more so. However, such data is not measured offshore so cannot be transmitted to the crews before flight planning. This is a similar situation to the question of heave. As offshore pilots we all knew that actual heave was not the real problem – it was/is heave rate. How many years did it take to finally get heave rate data introduced? How many years will it take for the ‘authorities’ to act on accurate sea state reporting?
Probability – what is the probability of having to ditch? 1 in 10 to power 7? 10 to 8? 10 to 9? Since 1989, there have been 5 separate incidents of G-reg helicopters ditching around the North Sea:
Apr 1989 G-BGKJ Bo105 Oil pollution flt near Scacsta 1 passenger
Jan 1995 G-TIGK AS332L Crew change flt near Brae A 16 pax
Nov 2006 G-JSAR AS332L2 Crew change? Dutch sector 13 pax
Feb 2009 G-REDU EC225 Crew change flt near ETAP 16 pax
May 2012 G-REDW EC225 Crew change flt near Aberdeen 12 pax
5 incidents in 23 years, all different reasons, but with the same end result – 60 pax in the sea. How does that stand up against the level of ‘probability’? Based on Aberdeen Airport’s latest figures, there are approx helicopter 500,000 passengers per year. That would amount to around 11.5 million in 23 years. 60 pax out of 11,500,000 – that’s about 1 in 200,000. I wonder how they feel about being just a ‘slim probability’. How do the oil workers perceive that probability? Let us not forget that these guys are just going to work. If they are late, so what? And perception is the key word here. Why are there no Chinooks flying offshore oil support today? Should the oil workers, your passengers, lose faith in the EC225 or the basic survivability of ditching, what then?
So, let’s look at what the ‘authorities’ have to say. A gentleman by the name of David Andrew Howson of the CAA SRG, issued a paper titled “RESEARCH INITIATIVES FOR IMPROVING THE SAFETY OF OFFSHORE HELICOPTER OPERATIONS” – link www.ihst.org/Portals/54/Partners/India/3_Howson.doc
Page 4 makes interesting reading.
Further suggested reading is HOSS/WP-99/8.5, (link http://www.jaa.nl/secured/Operations...20Survival.pdf) extracts below:
The history of North Sea oil support helicopters has been one of continuing safety improvements. In the early days, neither pilots nor passenger had survival suits or even lifejackets. Offshore survival training didn’t exist. No HUMS systems, single engine helicopters, single pilot operations, DECCA moving maps. I could go on, but you should get my drift. The industry must continue to improve safety and the perception of safety.
bondu
Edited to correct figures - thanks John
You are quite correct to point out that wave height alone is not sufficient. The wavelength and period, leading to the steepness of the waves are just as important, if not more so. However, such data is not measured offshore so cannot be transmitted to the crews before flight planning. This is a similar situation to the question of heave. As offshore pilots we all knew that actual heave was not the real problem – it was/is heave rate. How many years did it take to finally get heave rate data introduced? How many years will it take for the ‘authorities’ to act on accurate sea state reporting?
Probability – what is the probability of having to ditch? 1 in 10 to power 7? 10 to 8? 10 to 9? Since 1989, there have been 5 separate incidents of G-reg helicopters ditching around the North Sea:
Apr 1989 G-BGKJ Bo105 Oil pollution flt near Scacsta 1 passenger
Jan 1995 G-TIGK AS332L Crew change flt near Brae A 16 pax
Nov 2006 G-JSAR AS332L2 Crew change? Dutch sector 13 pax
Feb 2009 G-REDU EC225 Crew change flt near ETAP 16 pax
May 2012 G-REDW EC225 Crew change flt near Aberdeen 12 pax
5 incidents in 23 years, all different reasons, but with the same end result – 60 pax in the sea. How does that stand up against the level of ‘probability’? Based on Aberdeen Airport’s latest figures, there are approx helicopter 500,000 passengers per year. That would amount to around 11.5 million in 23 years. 60 pax out of 11,500,000 – that’s about 1 in 200,000. I wonder how they feel about being just a ‘slim probability’. How do the oil workers perceive that probability? Let us not forget that these guys are just going to work. If they are late, so what? And perception is the key word here. Why are there no Chinooks flying offshore oil support today? Should the oil workers, your passengers, lose faith in the EC225 or the basic survivability of ditching, what then?
So, let’s look at what the ‘authorities’ have to say. A gentleman by the name of David Andrew Howson of the CAA SRG, issued a paper titled “RESEARCH INITIATIVES FOR IMPROVING THE SAFETY OF OFFSHORE HELICOPTER OPERATIONS” – link www.ihst.org/Portals/54/Partners/India/3_Howson.doc
Page 4 makes interesting reading.
Further suggested reading is HOSS/WP-99/8.5, (link http://www.jaa.nl/secured/Operations...20Survival.pdf) extracts below:
“Taken on their own, the FAR/JAR would require the designer to select a reasonably severe wave condition for the area in which he expects the helicopter to operate and to demonstrate that the probability of a capsize has been minimised. FAA and JAA however, have adopted an interpretation (AC29-2A para 337(a)(3)) which states that Sea State 4 is considered to satisfy the reasonably probable requirement.”
“Although sea keeping qualities vary from one helicopter type to another, most types currently in use will capsize in sea states in the range 4 to 5 and above. A recent study of wave climates along a representative selection of main helicopter routes in the northern North Sea and West of Shetland (regarded in JAR-OPS 3 as a Hostile environment), indicates that Sea State 4 will be exceeded on 26-36% of occasions over the whole year (Ref. 1). During the winter period between December-February, this increases to between 51-65%. If the certification requirement was raised to Sea State 6, the risk of exceedence would fall to a maximum of approximately 3% over the whole year and 3-7% in the winter months.”
bondu
Edited to correct figures - thanks John
Last edited by bondu; 21st May 2012 at 13:52.
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EASA AD 2012-0087 EC225
5 incidents in 23 years, all different reasons, but with the same end result – 60 pax in the sea. How does that stand up against the level of ‘probability’? Based on Aberdeen Airport’s latest figures, there are approx helicopter 500,000 passengers per year. That would amount to around 11.5 million in 23 years. 60 pax out of 11,500,000 – that’s about 1 in 1,000,000.
All NS offshore helicopters were twins, DECCA was as good as you could expect and generally did a good job if you had the DANAC version, SP ops for rig shuttles but two pilot for crew changes.
HUMS was up there with pagers, mobile phones and the internet. We didn't have them because they hadn't been invented
During the winter period between December-February, this increases to between 51-65%. If the certification requirement was raised to Sea State 6, the risk of exceedence would fall to a maximum of approximately 3% over the whole year and 3-7% in the winter months.”
Perhaps there is merit to requiring Sea State 6 flotation systems. It will still come down to a determination of cost/benefit....which unfortunately has to be measured in human lives at some point.
If we use the logic of some....comparing the offshore helicopter industry to the World's Airline industry....should we not first agree we should have the same reliability numbers that the Airlines maintain?
When we do....have the same reliability, fully instrumented approaches, lead in lighting, radar surveillance, stable landing areas....and all the rest....then perhaps that is a fair comparison....but not until then.
Even then....would we revert to wearing our normal casual attire to/from the rigs and platforms?
John me old Son....
I distinctly remember being single pilot, two channel SAS, Mk 19 Decca (pre TANS), and flogging between Teeside and the Ekofisk in a S-58T, wearing a Musk Ox Rubber/Canvas Survival suit and Nomex flight suit.
When we started the Ninian Shuttle....as the field was being built....we were two Pilot crews.
I drew the line at night Single Pilot....Ma's favorite Son preferred having two feet solidly ashore once the Sun went down. It did not make me very popular with some of the Office Pilots but I am here today all fat and sassy.
We lost one 212 and almost lost a 58T doing single pilot night flights offshore. One disappeared and the other had to be rebuilt after going inverted (or some very unusual attitude in that the cabin attendant commented about standing on the overhead of the cabin).
What I am saying....is Bondu is closer to the truth than you are. Your experience was on the Brent Shuttle as I recall.
Bristow had been operating Whirlwinds, then Wessex offshore long before the S-58T and 212's showed up.
Also...my memory of the Mk 19 Decca is this.....I want to meet and shake the hand of any Man that ever did the Decca approach to Sumburgh, Single Pilot, at Night, IMC, in Snow, in a S58T or Wessex. That is the approach that required both a Map and Key change. I personally do not believe it is possible to multi-task to that degree! One would have to have the arms of an Octopus and the mental dexterity of a couple of Einsteins to get that done and remain greasy side up.
There has been a lot of improvement on the North Sea.....but there is no reason to stop improving yet.
I distinctly remember being single pilot, two channel SAS, Mk 19 Decca (pre TANS), and flogging between Teeside and the Ekofisk in a S-58T, wearing a Musk Ox Rubber/Canvas Survival suit and Nomex flight suit.
When we started the Ninian Shuttle....as the field was being built....we were two Pilot crews.
I drew the line at night Single Pilot....Ma's favorite Son preferred having two feet solidly ashore once the Sun went down. It did not make me very popular with some of the Office Pilots but I am here today all fat and sassy.
We lost one 212 and almost lost a 58T doing single pilot night flights offshore. One disappeared and the other had to be rebuilt after going inverted (or some very unusual attitude in that the cabin attendant commented about standing on the overhead of the cabin).
What I am saying....is Bondu is closer to the truth than you are. Your experience was on the Brent Shuttle as I recall.
Bristow had been operating Whirlwinds, then Wessex offshore long before the S-58T and 212's showed up.
Also...my memory of the Mk 19 Decca is this.....I want to meet and shake the hand of any Man that ever did the Decca approach to Sumburgh, Single Pilot, at Night, IMC, in Snow, in a S58T or Wessex. That is the approach that required both a Map and Key change. I personally do not believe it is possible to multi-task to that degree! One would have to have the arms of an Octopus and the mental dexterity of a couple of Einsteins to get that done and remain greasy side up.
There has been a lot of improvement on the North Sea.....but there is no reason to stop improving yet.
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John,
Apologies on the figures!
As for single pilot ops, I was still doing crew changes from Unst out to the Ninians single pilot in 1992. Yes, most of the flying was inter rig shuttles, but it was common the fly up to three pax in and out of Unst if the loads were too high for the S61s.
As for DECCA DANAC, yes it was the best at the time. But that's precisely my point - things have improved. New technology, new ways of operating etc. That's what should happen, isn't it? We have to keep pushing for better kit, better understanding of the environmental conditions we operate in.
bondu
Apologies on the figures!
As for single pilot ops, I was still doing crew changes from Unst out to the Ninians single pilot in 1992. Yes, most of the flying was inter rig shuttles, but it was common the fly up to three pax in and out of Unst if the loads were too high for the S61s.
As for DECCA DANAC, yes it was the best at the time. But that's precisely my point - things have improved. New technology, new ways of operating etc. That's what should happen, isn't it? We have to keep pushing for better kit, better understanding of the environmental conditions we operate in.
bondu
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SASless,
I spent three years operating from Ninian North - all single pilot, day/night IFR. With a DECCA moving map that 'jumped' a lane in heavy rain - just when you needed it most! Those were the days!! Tell the young uns today and they'll never believe you!
You are absolutely correct - this is not the time to stop pushing for improvements!
bondu
I spent three years operating from Ninian North - all single pilot, day/night IFR. With a DECCA moving map that 'jumped' a lane in heavy rain - just when you needed it most! Those were the days!! Tell the young uns today and they'll never believe you!
You are absolutely correct - this is not the time to stop pushing for improvements!
bondu
What fun this kit was to operate in anything that had "static" like rain or snow! It worked great on nine knot ships surrounded by water!
gasax, sorry but if you are saying it is incorrect that many fewer people have died in transit by helicopter to/from offshore North Sea, than have died whilst working on North Sea oil/gas installations, then I find it very hard to believe and please provide the figures and the source.
If you want to factor it by the number of hours of exposure, then possibly you are right because they spend a long time offshore, and a short time in the helicopter. However in terms of the risk encountered when doing a job offshore, I would consider that to be distorting the figures because it is surely the overall probability of coming to grief during an offshore rotation that is the real-world issue.
If the same number of people had onshore jobs, how many more or less would have died on the roads driving to work every day, than did in a helicopter?
HC
If you want to factor it by the number of hours of exposure, then possibly you are right because they spend a long time offshore, and a short time in the helicopter. However in terms of the risk encountered when doing a job offshore, I would consider that to be distorting the figures because it is surely the overall probability of coming to grief during an offshore rotation that is the real-world issue.
If the same number of people had onshore jobs, how many more or less would have died on the roads driving to work every day, than did in a helicopter?
HC
Last edited by HeliComparator; 21st May 2012 at 14:47.
