Helicopter crash off the coast of Newfoundland - 18 aboard, March 2009
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CHC's response is well spelled out here,
Timeline - Cougar 491 | the fifth estate
About half way down the page, with links to various documents.
Timeline - Cougar 491 | the fifth estate
About half way down the page, with links to various documents.
Of the two CHC documents:
1) Is an occurrence report that covers events up to landing
2) Is an email that mainly focuses on the poor service history of the S-92 gearbox
The other documents (and yopur second link) mostly relate to the lab testing. I was well aware of those investigative documents.
However there are no comments on any of the possible safety actions I would have expected would have been considered:
Safety alert on repair authorisation?
Tighter maintenance control at Broome?
Change in maintenance programme?
A notice to crew about oil loss and what 'Land Immediately' means?
revised training?
Tighter maintenance control at Broome?
Change in maintenance programme?
A notice to crew about oil loss and what 'Land Immediately' means?
revised training?
Wow, I've just read the following column in a Canadian Helicopter magazine which states:
So it was the crews fault????
I suppose he means FAR part 29 and I'd like to remind him what is says in the FAR's
(1) Category A. Unless such failures are extremely remote, it must be shown by test that any failure which results in loss of lubricant in any normal use lubrication system will not prevent continued safe operation, although not necessarily without damage, at a torque and rotational speed prescribed by the applicant for continued flight, for at least 30 minutes after perception by the flightcrew of the lubrication system failure or loss of lubricant.
I would say that the similar problem in the southern hemisphere should be counted to show that failure was NOT extemely remote and a 30 minute test should have been demanded by FAA and Transport Canada.
The columns "author" provides accident reconstruction and "expert" opinions to law firms and the courts.
Some aviators believe FAA part 29 requires the transmision to be able to run dry for 30 minutes. It does not. While I realize some will observe hindsight is 20/20, the only prudent action by the ill fated crew was essentially "written in stone". Had the pilots initiated an immediate and accelerated descent to landing on the water with a deployed emergency flotation system and prepared to abandon the helicopter if the sea state dictaed evacuation - everyone could have lived.
I suppose he means FAR part 29 and I'd like to remind him what is says in the FAR's
(1) Category A. Unless such failures are extremely remote, it must be shown by test that any failure which results in loss of lubricant in any normal use lubrication system will not prevent continued safe operation, although not necessarily without damage, at a torque and rotational speed prescribed by the applicant for continued flight, for at least 30 minutes after perception by the flightcrew of the lubrication system failure or loss of lubricant.
I would say that the similar problem in the southern hemisphere should be counted to show that failure was NOT extemely remote and a 30 minute test should have been demanded by FAA and Transport Canada.
The columns "author" provides accident reconstruction and "expert" opinions to law firms and the courts.
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GT - Out of interest - Which magazine? Is it available online?
212man - While some slackness by the lawyer is regrettable, he seems to have got more right than Sikorsky's MGB designers.
212man - While some slackness by the lawyer is regrettable, he seems to have got more right than Sikorsky's MGB designers.
Digital version on line at www.helicoptersmagazine.com See page 38
Gemini, did you read the TSB report?
The copilot more than once alerted the Pilot in Command that they were in a land immediately emergency/malfunction.
This in no way excuses whaterver design and maintenance errors may be surmised or determined from this mishap, nor the decisions post Broone that did or didn't get made and executed.
It seems to me that a cogent point being made is that "lost helicopter, BUT crew and pax survive" was a future foreclosed by the decision not to Land Immediately, or fly at a profile that allowed a quick flare and safe landing (see my remark a few pages up on the old Hawk 80/80 limp home speed with transmission problems, not sure what the S-92 similar profile would be). Lost helicopter, AND lost crew and pax(save one) is what sadly happened. Understanding the decision tree involved in the Captain's decision not to Land Immediately seems to me a crucial lesson learned, if one can be. Crews are faced with tough decisions all the time. How does one prepare crews to do so?
From the report, I feel comfortable taking the position that the crew's type training, as well as the training and flight manuals used, can be flagged as a "supervisory error" on the human side that contributed to the loss of life, if we accept that loss of the airframe was a mostly mechanical and maintenance issue, rather than a flying issue.
The reports provide a valid possiblity that the captain's choice not to ditch while it was still flying was informed by a training regime that didn't address the system he was flying with sufficient depth for critical items and critical actions.
That said, SASless' point remains well worth considering for anyone flying over very cold and rough water: would any of us ever want to ditch in high sea state, cold water, if we believed the bird could keep flying?
I seriously doubt I would ever have.
The copilot more than once alerted the Pilot in Command that they were in a land immediately emergency/malfunction.
This in no way excuses whaterver design and maintenance errors may be surmised or determined from this mishap, nor the decisions post Broone that did or didn't get made and executed.
It seems to me that a cogent point being made is that "lost helicopter, BUT crew and pax survive" was a future foreclosed by the decision not to Land Immediately, or fly at a profile that allowed a quick flare and safe landing (see my remark a few pages up on the old Hawk 80/80 limp home speed with transmission problems, not sure what the S-92 similar profile would be). Lost helicopter, AND lost crew and pax(save one) is what sadly happened. Understanding the decision tree involved in the Captain's decision not to Land Immediately seems to me a crucial lesson learned, if one can be. Crews are faced with tough decisions all the time. How does one prepare crews to do so?
From the report, I feel comfortable taking the position that the crew's type training, as well as the training and flight manuals used, can be flagged as a "supervisory error" on the human side that contributed to the loss of life, if we accept that loss of the airframe was a mostly mechanical and maintenance issue, rather than a flying issue.
The reports provide a valid possiblity that the captain's choice not to ditch while it was still flying was informed by a training regime that didn't address the system he was flying with sufficient depth for critical items and critical actions.
That said, SASless' point remains well worth considering for anyone flying over very cold and rough water: would any of us ever want to ditch in high sea state, cold water, if we believed the bird could keep flying?
I seriously doubt I would ever have.
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GT Thanks for that.
LW Especially if they were confident in the aircraft.
I've just looked back at a presentation given by the 'Director - S-92 Programs' in May 2003:
Page 2 starts by setting up requirements as a key part of the sales pitch
Page 4 is ironic considering the parts that failed in Broome and St Johns
Only the S-92 is Flaw and Damage Tolerant
Critical Structures Absorb Flaws, Damage and Corrosion
From now on, helicopters will not be brought down by small corrosion pits, dents and damage due to field use!
Slide 42 rings very hollow now
Page 53 confusingly states
Only S-92 Is Designed and Tested to the Latest Standards for Safety and Robustness
Considering what was after the gearbox change the use of 'adapted' rather than 'adopted' looks like a Freudian slip.
Page 54 then has a photo of the Collier Trophy, awarded for 2002 to the S-92.
Other observations:
Amusingly on page 18, in discussing an accident, the identity of the type involved is deleted as 'not germane' (though their is a web address and date for the accident report), whereas on page 21 the S-92 is compared to another type, but the references are for S-92 and EH101. Is it churlish to point out that is was very germane to the VXX cometition?
Page 32 covers the SAR modes, not yet certified by FAA.
LW Especially if they were confident in the aircraft.
I've just looked back at a presentation given by the 'Director - S-92 Programs' in May 2003:
Page 2 starts by setting up requirements as a key part of the sales pitch
The S-92 is the 21st Century Aircraft
Complies with the Latest Standards and Regulations
Only the S-92 complies with all NEW FAA requirements of Part 29, amendment 45
Complies with the Latest Standards and Regulations
Only the S-92 complies with all NEW FAA requirements of Part 29, amendment 45
Page 4 is ironic considering the parts that failed in Broome and St Johns
Only the S-92 is Flaw and Damage Tolerant
Critical Structures Absorb Flaws, Damage and Corrosion
From now on, helicopters will not be brought down by small corrosion pits, dents and damage due to field use!
Sikorsky Design Attention Will Continue Long After Production Delivery
Failure reporting and Corrective Action System (FRACAS)
Failure reporting and Corrective Action System (FRACAS)
- Has been in effect since first flight on S-92
- FRACAS System studies Items that affect safety, reliability, andcost
- Relentless pursuit of problems will continue through Sikorsky World Wide Customer Service
- Design engineers will continue to study and fix these problems
- Operators, Sikorsky, Partners and Suppliers will work as a team to continue to improve the S-92 long into the future.
Only S-92 Is Designed and Tested to the Latest Standards for Safety and Robustness
- To keep ahead of increasing safety standards, S-92 was designed to meet regulations not yet adapted {SIC} at the time
Page 54 then has a photo of the Collier Trophy, awarded for 2002 to the S-92.
Other observations:
Amusingly on page 18, in discussing an accident, the identity of the type involved is deleted as 'not germane' (though their is a web address and date for the accident report), whereas on page 21 the S-92 is compared to another type, but the references are for S-92 and EH101. Is it churlish to point out that is was very germane to the VXX cometition?
Page 32 covers the SAR modes, not yet certified by FAA.
I've have read everything since the day it happened and I'm as shocked today as I was when I first noted that the S92 did not have to have a 30 min. loss of lube test prior to certification.
It's been my experience that the "extremely remote" alternate means of compliance is to be based on extensive in service histroy of a similar type. The S92 was a brand new type certified Cat A to FAR part 29!
Those guys should have had a better chance, it's not just 30 minutes run dry, but 30 minutes at a cruise power to be specified and approved by FAA prior to the test.
I've held my comments until know and only chipping in because of the column in Helicopters magazine today, which seem to point directly at the crew. "If the pilots had initiated an immediate.... everyone could have lived."
It's been my experience that the "extremely remote" alternate means of compliance is to be based on extensive in service histroy of a similar type. The S92 was a brand new type certified Cat A to FAR part 29!
Those guys should have had a better chance, it's not just 30 minutes run dry, but 30 minutes at a cruise power to be specified and approved by FAA prior to the test.
I've held my comments until know and only chipping in because of the column in Helicopters magazine today, which seem to point directly at the crew. "If the pilots had initiated an immediate.... everyone could have lived."
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'adapted' rather than 'adopted'
I'm not sure if I should laugth or cry.
Gemini Twin
What is odd is that column was written almost 2 years after the accident, but perhaps just a month before the final report - a dumb way to get caught out as a columnist.
Sweeping geralisation alert:
Whatever kind of helicopter you fly, from a Bell 47 to a Boeing CH-47, a loss of MGB transmission pressure dictates an immediate landing.
The author also isn't familiar with how the S-92A floats are activated.
LW50. I get your point but....
zalt.
Most ignorant piece I've seen on the subject, but then again he's an expert who provides accident reconstruction and expert opinions to law firms and courts. That makes it all OK then.
zalt.
Most ignorant piece I've seen on the subject, but then again he's an expert who provides accident reconstruction and expert opinions to law firms and courts. That makes it all OK then.
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It's been my experience that the "extremely remote" alternate means of compliance is to be based on extensive in service histroy of a similar type. The S92 was a brand new type certified Cat A to FAR part 29!
Wrt. the article written by Ken Armstrong perhaps he was alleviating to err on the side of caution i.e. don't rely on any run-dry time or glycol cooling or whatever the manufacturer tells you will work.
I myself as a PAX would rather take my chances with a ditching than an unknown MRGB real-time run-dry time with a full contingent of SLF, baggage, and whatever crappy weather the offshore throws at us.
Many lessons are to be learnt from 491 by all. Bashing a column based on data prior to the TSB report release isn't helping anybody. In fact IMHO the opposite is true as the column raises awareness again of the S92's MRGB limitations and the inherent issues in CRM, FSI, ops procedures and the RFM.
Safe flying
Max
Thanks for the reply, GT.
The amount of "lore" versus actual systems knowledge that accrues to an airframe, helicopter or fixed wing, grows and shrinks as facts fill in the blanks. It could very well have been some of that "lore" that led the pilot in command into thinking he had time that he didn't actually have. As that point has been beaten into the ground and covered again and again in this thread, I'll leave it at that.
The amount of "lore" versus actual systems knowledge that accrues to an airframe, helicopter or fixed wing, grows and shrinks as facts fill in the blanks. It could very well have been some of that "lore" that led the pilot in command into thinking he had time that he didn't actually have. As that point has been beaten into the ground and covered again and again in this thread, I'll leave it at that.
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GT,
I agree with your comments you made regarding an article found in the back of a Helicopter magazine.
Traditionally helicopters are equipped with a MBG Oil pressure transmitter from which the MGB oil pressure indicator derives its signal, in addition to the MGB oil temp indicator there Is a low pressure switch which turns on a low pressure warning light.
In the S92 the pressure transmitter signal is also used to turn on a Caution message thru software in the DCU, I believe that it is possible the crew may have believed that when the caution message was changed to a warning message this to be coming from the same source (its is not). Further more The S 92 has over a 100 messages it would be hard to remember the source of each message. Also having been around a few oil leaks they often did result in a passenger to notify the pilot.
Engineering at SAC did think losing all oil to be "extremely remote" so now the pilot gets 5 minutes to make the dissison to try to safe all or land in the Atlantic.
The amount of harsh comments regarding the crew who paid the ultimate price due to bad engineering at SAC is shocking to me.
I agree with your comments you made regarding an article found in the back of a Helicopter magazine.
Traditionally helicopters are equipped with a MBG Oil pressure transmitter from which the MGB oil pressure indicator derives its signal, in addition to the MGB oil temp indicator there Is a low pressure switch which turns on a low pressure warning light.
In the S92 the pressure transmitter signal is also used to turn on a Caution message thru software in the DCU, I believe that it is possible the crew may have believed that when the caution message was changed to a warning message this to be coming from the same source (its is not). Further more The S 92 has over a 100 messages it would be hard to remember the source of each message. Also having been around a few oil leaks they often did result in a passenger to notify the pilot.
Engineering at SAC did think losing all oil to be "extremely remote" so now the pilot gets 5 minutes to make the dissison to try to safe all or land in the Atlantic.
The amount of harsh comments regarding the crew who paid the ultimate price due to bad engineering at SAC is shocking to me.
The amount of harsh comments regarding the crew who paid the ultimate price due to bad engineering at SAC is shocking to me.
After reading the TSB report, I believe it speaks volumes for the benefits of the crashworthy systems required by the latest Part 27/29 regs.
No antemortem injuries to 7 of the 16 pax. Minor contusions to another, but all survived the impact at 2300'/min. vertical and 55-60 knots fwd speed. Two escaped the airframe, but only one made it to the surface.
Kudos to those who demand this level of safety in what they strap their (and their customers) butt to.
No antemortem injuries to 7 of the 16 pax. Minor contusions to another, but all survived the impact at 2300'/min. vertical and 55-60 knots fwd speed. Two escaped the airframe, but only one made it to the surface.
Kudos to those who demand this level of safety in what they strap their (and their customers) butt to.
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While you are factually correct:
But 14 of the 16 pax failed to escape from the aircraft
15 of the 16 pax failed to survive.
Both crewwere badly injured by contact with the structure in the cockpit and unable to escape. TSB have already recommended helmets for pilots.
I see Cougar now partly fund helemts for their crew. I wonder if their SAR crews have to pay towards their own safety equipment.
A case of a crashworthiness success but 94% of the occupants perished?
it speaks volumes for the benefits of the crashworthy systems...
No antemortem injuries to 7 of the 16 pax. Minor contusions to another, but all survived the impact at 2300'/min.
No antemortem injuries to 7 of the 16 pax. Minor contusions to another, but all survived the impact at 2300'/min.
15 of the 16 pax failed to survive.
Both crewwere badly injured by contact with the structure in the cockpit and unable to escape. TSB have already recommended helmets for pilots.
I see Cougar now partly fund helemts for their crew. I wonder if their SAR crews have to pay towards their own safety equipment.
A case of a crashworthiness success but 94% of the occupants perished?
Both of you are correct.....let's see if you can agree on why how to change that survival rate! What caused the lack of successful escape from the aircraft? Cold Water....being knocked senseless by the impact....lack of HEEDS air....bad exits....survival suits failed/delayed exit.....what was it?
Better Immersion Suits, EUBA, more frequent HUET.....all would have helped. unfortunately, all 15 died from drowning.
Point I was trying to make is that crashworthy features do work but far too many pilots ignore the advances they have brought to this industry.
Had that accident happened onshore, the results would have been significantly different.
Point I was trying to make is that crashworthy features do work but far too many pilots ignore the advances they have brought to this industry.
Had that accident happened onshore, the results would have been significantly different.
Leaving aside the reason for the crash/ditching (which has been endlessly discussed over the last two years) there are three main elements which have to be considered when a helicopter comes into contact with the water:
The objective of 2. is facilitated by a number of elements, most of which are satisfied when "certification with ditching provisions is requested". These provision include structural integrity, behaviour of the helicopter in a water landing and 'under reasonably probably water conditions (that) the flotation time and trim...will allow the occupants to leave the rotorcraft and enter the life rafts...'. Ditching approval is usually only required when specified by the Operational Regulations (as it is in ICAO Annex 6 Chapter 2.2.12 and JAR-OPS 3.843).
Point 3. is covered by other provisions (once again, in the Operational Regulations) which specify the carriage of life-rafts (and provisions to ensure that they are available and can be launched) the wearing of survival suits, constant wear life vests, the provision of pop-out windows and measures to ensure that the life-rafts are not punctured immediately after their launching. Operational rules also contain elements to ensure that the location of the helicopter is known during flight and also after ditching.
Some important issues spring to mind (discussed in the accident report): in AC 29-2C is contained the following clarifying text:
* From AC 29-2C it is established that Sea State 4 (wind 17kts - 21kts and signification wave height of 4 to 8 ft).
As you will have seen from the statistics in the report, the Sea State in the Canadian East Coast, the North Sea (and most other open bodies of water North of 45N and South of 45S) is above SS4 for a significant proportion of the time in the winter. Almost a decade ago, there was an attempt to have the AC amended to take account of that fact - it was not successful. In the meantime, the oil companies, deciding that they could not rely upon the regulator to make changes to the guidance, through discussions with the manufacturers and by contractual arrangements, decided to press ahead in an attempt to meet Sea State 6.
Helicopters can survive upright in quite high sea states - if the waves are regular. As we all know, it is the breaking of the wave that dictates when capsize occurs. For that reason, nothing modelled/established in regular waves can be guaranteed. Because we know that it is likely that the helicopter - with its high centre of gravity - will capsize, the principle of 'side floating' was investigated. (Side floating is intended to ensure that after a capsize, one side of the cabin will remain above water.) It is not easy to retrofit but it can be done.
As has been seen from this accident (and as was established in the RHOSS Report in 1995), most passengers will survive an initial impact but will subsequently drown in the cabin. The reasons why are complex. 'Brooks' established in his Canadian trials that breath-hold capacity was insufficient to permit evacuation of the passengers through the emergency exits, following a capsize. We know that cold shock can reduce the breath-hold capacity to less than 10 seconds - even for very experienced personnel. It is for that reason that pop-out windows are provided with the proviso that every passenger should be only one removed from the emergency exit.
Even with this it may also be necessary to increase the size of the pop-out windows and provide a method of increasing the breath-hold time to ensure it exceeds the escape time - by some margin.
Automatic float inflation and externally-launched life-rafts have been systematically fitted in the offshore fleet. It is real progress. However, during a crash, any portions of the emergency kit that is in the impact zone is likely to be damaged and cease to function. We have seen in modelling tests that critical elements of the emergency equipment can be lifted away from the likely impact zone - attention must be paid when considering such reasonably probable events.
Just some points with an impact upon offshore survivability.
Jim
- if the helicopter is performing other than a controlled manoeuvre; crashworthiness (seat stroking, maintenance of the integrity of the cabin, retention of the seats to their fixings, etc).
- the ability of the occupant to escape from the cabin.
- the ability to survive in open water after escaping from the cabin.
The objective of 2. is facilitated by a number of elements, most of which are satisfied when "certification with ditching provisions is requested". These provision include structural integrity, behaviour of the helicopter in a water landing and 'under reasonably probably water conditions (that) the flotation time and trim...will allow the occupants to leave the rotorcraft and enter the life rafts...'. Ditching approval is usually only required when specified by the Operational Regulations (as it is in ICAO Annex 6 Chapter 2.2.12 and JAR-OPS 3.843).
Point 3. is covered by other provisions (once again, in the Operational Regulations) which specify the carriage of life-rafts (and provisions to ensure that they are available and can be launched) the wearing of survival suits, constant wear life vests, the provision of pop-out windows and measures to ensure that the life-rafts are not punctured immediately after their launching. Operational rules also contain elements to ensure that the location of the helicopter is known during flight and also after ditching.
Some important issues spring to mind (discussed in the accident report): in AC 29-2C is contained the following clarifying text:
The FAA/AUTHORITY has determined that a sea state 4 is representative of reasonably probable water conditions to be encountered. Therefore, demonstration of compliance with the ditching requirements for at least sea state 4* water conditions is considered to satisfy the reasonably probable requirement.
As you will have seen from the statistics in the report, the Sea State in the Canadian East Coast, the North Sea (and most other open bodies of water North of 45N and South of 45S) is above SS4 for a significant proportion of the time in the winter. Almost a decade ago, there was an attempt to have the AC amended to take account of that fact - it was not successful. In the meantime, the oil companies, deciding that they could not rely upon the regulator to make changes to the guidance, through discussions with the manufacturers and by contractual arrangements, decided to press ahead in an attempt to meet Sea State 6.
Helicopters can survive upright in quite high sea states - if the waves are regular. As we all know, it is the breaking of the wave that dictates when capsize occurs. For that reason, nothing modelled/established in regular waves can be guaranteed. Because we know that it is likely that the helicopter - with its high centre of gravity - will capsize, the principle of 'side floating' was investigated. (Side floating is intended to ensure that after a capsize, one side of the cabin will remain above water.) It is not easy to retrofit but it can be done.
As has been seen from this accident (and as was established in the RHOSS Report in 1995), most passengers will survive an initial impact but will subsequently drown in the cabin. The reasons why are complex. 'Brooks' established in his Canadian trials that breath-hold capacity was insufficient to permit evacuation of the passengers through the emergency exits, following a capsize. We know that cold shock can reduce the breath-hold capacity to less than 10 seconds - even for very experienced personnel. It is for that reason that pop-out windows are provided with the proviso that every passenger should be only one removed from the emergency exit.
Even with this it may also be necessary to increase the size of the pop-out windows and provide a method of increasing the breath-hold time to ensure it exceeds the escape time - by some margin.
Automatic float inflation and externally-launched life-rafts have been systematically fitted in the offshore fleet. It is real progress. However, during a crash, any portions of the emergency kit that is in the impact zone is likely to be damaged and cease to function. We have seen in modelling tests that critical elements of the emergency equipment can be lifted away from the likely impact zone - attention must be paid when considering such reasonably probable events.
Just some points with an impact upon offshore survivability.
Jim
Jim, very well stated on the issue of combining both the upset of capsized helicopter and the shock hazard of very cold water. I was skeptical of HEEDS when it first came out, in the USN, over 20 years ago, but a couple of my friends were in mishaps with HEEDS available and made me into a believer. It gives you those blessed extra seconds of not having to deal with "where the hell is my air?" while allowing one to deal with with "get out hand over hand before this thing takes me to the bottom!"