Helicopter crash off the coast of Newfoundland - 18 aboard, March 2009
As Flyt3est has indicated, the HHMAG (a group which contained the world-wide great and good of the HUMS community - what a pity the advent of EASA caused its demise) discussed cockpit indication at length.
Because the issue was so complex and in view of the lack (at that time) of the required level of reliability, and the simplicity of the systems (events only - and even those provided on a heuristic basis) - a working group was tasked to consider it in detail. This group made a finding that, for the time being, cockpit indications would only complicate the life of the pilot - not simplify it. It also reiterated that the aim of HUMS was to spot developing faults, clusters and trends in time for them to be addressed on the ground and before they could impact upon a flight.
In common with others, I still have my doubts that cockpit indications provide the answer. Perhaps the problem is believing a primary indication that appears irrational and cannot be confirmed by some other means. It could be that, in these days of digital systems and software control, more effort is required in the provision of algorithms that provide (and indicate) secondary confirmation based upon alternative diagnosis paths.
In passing I must say I was amazed at the complexity of the S92 emergency checklist - surely this information could have been better presented in the form of a flow-chart (and this provided on some diagnostic screen with all paths shown and coloured appropriately).
Jim
Because the issue was so complex and in view of the lack (at that time) of the required level of reliability, and the simplicity of the systems (events only - and even those provided on a heuristic basis) - a working group was tasked to consider it in detail. This group made a finding that, for the time being, cockpit indications would only complicate the life of the pilot - not simplify it. It also reiterated that the aim of HUMS was to spot developing faults, clusters and trends in time for them to be addressed on the ground and before they could impact upon a flight.
In common with others, I still have my doubts that cockpit indications provide the answer. Perhaps the problem is believing a primary indication that appears irrational and cannot be confirmed by some other means. It could be that, in these days of digital systems and software control, more effort is required in the provision of algorithms that provide (and indicate) secondary confirmation based upon alternative diagnosis paths.
In passing I must say I was amazed at the complexity of the S92 emergency checklist - surely this information could have been better presented in the form of a flow-chart (and this provided on some diagnostic screen with all paths shown and coloured appropriately).
Jim
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You are quite right about the "wing" mirrors on the Super Puma fleets but at one company we had to fight to get them on, even though the S61N's had them fitted, as they were seen to be causing drag.
JimL,
Are you referring to the one I posted previously or the actual Sikorsky Checklist?
If you have access to a Bell 412 checklist you will see it is just as elaborate as the 92 checklist.
We have to remember the Factory Check List is written for all cases, generic operations, and thus will not necessarily be in the best layout for use in every cockpit.
Does not the CAA allow the operator to write their own version of the aircraft checklist?
The FAA in Part 135 requires the operator to do so. Most merely use the factory checklist but some operators do construct their own and submit it to the FAA for approval.
Probably the best checklist I ever used was the Bristow S-58T checklist we had in the mid-70's. The layout and content was excellent with both the Normal Procedures and Emergency Procedures contained in the same flip chart style document. When folded to the cover page....one either saw the Normal Section or turn the chart around and you had the Emergency Section and each had tabbed pages for the various procedures so you could locate what you were looking for with ease.
n passing I must say I was amazed at the complexity of the S92 emergency checklist - surely this information could have been better presented in the form of a flow-chart (and this provided on some diagnostic screen with all paths shown and coloured appropriately).
If you have access to a Bell 412 checklist you will see it is just as elaborate as the 92 checklist.
We have to remember the Factory Check List is written for all cases, generic operations, and thus will not necessarily be in the best layout for use in every cockpit.
Does not the CAA allow the operator to write their own version of the aircraft checklist?
The FAA in Part 135 requires the operator to do so. Most merely use the factory checklist but some operators do construct their own and submit it to the FAA for approval.
Probably the best checklist I ever used was the Bristow S-58T checklist we had in the mid-70's. The layout and content was excellent with both the Normal Procedures and Emergency Procedures contained in the same flip chart style document. When folded to the cover page....one either saw the Normal Section or turn the chart around and you had the Emergency Section and each had tabbed pages for the various procedures so you could locate what you were looking for with ease.
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Power Supplies for S-92 CVR & FDR
S92 Mech,
What is the power source for the CVR and FDR? Is it powered by AC Primary Bus or DC primary bus receiving power only from main generators or APU? You may understand where I'm going here
Pave
What is the power source for the CVR and FDR? Is it powered by AC Primary Bus or DC primary bus receiving power only from main generators or APU? You may understand where I'm going here
Pave
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power for the CVR/FDR 1 and 2 comes from the primary busses under normal circimstances, and will run when powered by the APU. the CVR/FDR 1 is also connected to the battery bus. an imersion senson or G sensor will shut it off to prevent data loss in an accident, cant remenber the figures though, something like 18G Horizontal and 20G vertical. dont quote me on the figures though, i dont have my books open at the page right now to confirm that!
332 Wing mirrors.
As I recall, Bristow being the lead Super Puma operators had a problem with the transmission fairing (doghouse) becoming loose before the reinforced fasteners were introduced. I think the wing mirrors were installed for the crew to keep an eye on the fairings in flight, of course, I stand to be corrected, it was some time ago.
As I recall, Bristow being the lead Super Puma operators had a problem with the transmission fairing (doghouse) becoming loose before the reinforced fasteners were introduced. I think the wing mirrors were installed for the crew to keep an eye on the fairings in flight, of course, I stand to be corrected, it was some time ago.
Last edited by Oldlae; 4th Apr 2009 at 08:05. Reason: clarity
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AS332 Wing Mirrors
The wing mirrors are part of the fit required for a limited icing clearance. They enable the crew to monitor any ice build up on the engine intake baskets.
The wing mirrors are part of the fit required for a limited icing clearance.
When the 332 was introduced in Aberdeen they were not fitted and were not going to be fitted because of weight until Doogal (RIP) had his double flameout.
Doogal got them both lit again and then all Bristows 332s sprouted mirrors virtually overnight.
Useful pieces of kit. No helicopter should be without them.
Same as the tail pylon hinge restraint. Just the rubber stopper until one started coming out of a 330J in 1978. They fitted a copy of the RAF 330C mod, a metal clamp. Come the 332 with a bigger rubber stopper. Had they learned? No, not until one came adrift again and the aircraft crunched in.
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Question about news story
Hi PPRuNe:
There is a story today, Apr. 7, (and there was another one yesterday) about the Newfoundland helicopter crash on the Globe and Mail's website. I made a couple of comments on that story, and one of the other posters directed me to this site.
I am a former (very former) journalist who did some work on aviation accidents. I have friends in the industry and military (now mostly retired). But that is the limit of my close experience with aviation.
I thought The Globe's reporters did a particularly good job with this story. But I wonder what people who post here, who know a great deal more about all this than I do, think of it.
There is a story today, Apr. 7, (and there was another one yesterday) about the Newfoundland helicopter crash on the Globe and Mail's website. I made a couple of comments on that story, and one of the other posters directed me to this site.
I am a former (very former) journalist who did some work on aviation accidents. I have friends in the industry and military (now mostly retired). But that is the limit of my close experience with aviation.
I thought The Globe's reporters did a particularly good job with this story. But I wonder what people who post here, who know a great deal more about all this than I do, think of it.
The problem with news stories as you reference is they are far from detailed enough and suffer the problem of limited length to be able to fairly discuss the topics and allow a reader to form an opinon based upon sufficient facts to be accurate.
The story was well written and seemed fairly objective but due to reasons I cite it raises more questions than it answers.
The situation is far more complex than can be addressed in a couple of thousand word article.
If they were to start a series and devote weeks worth of space they might do a much better job of describing the situation but they would have to do a lot of research and interview a great number of people to do so effectively.
Are they willing to devote those kinds of assets to the project?
The story was well written and seemed fairly objective but due to reasons I cite it raises more questions than it answers.
The situation is far more complex than can be addressed in a couple of thousand word article.
If they were to start a series and devote weeks worth of space they might do a much better job of describing the situation but they would have to do a lot of research and interview a great number of people to do so effectively.
Are they willing to devote those kinds of assets to the project?
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I don't think the story was fair at all for the following reasons:
From a post I made on another forum:
With all of the hype and media crap arguing about the "30 min run dry capability", I would suggest that everybody use caution in their interpretation of what is being discussed.
Remember one important fact. The present S92A Flight Manual does not state anywhere in the Emergency Procedures that continued 30 min flight is allowed for the type of indications this crew were faced with. This was not a BYP (Bypass) problem
From the flight manual:
If the MGB OIL PRES warning or the MGB OIL PRES caution and any of the following secondary indications of gearbox
failure are observed:
MGB oil pressure below 5 psi
Smoke or fumes in the cabin
Any subsequent hydraulic system failure
Progressively increasing power required to maintain flight
Unusual vibrations or noises.
6. Land immediately.
Therefore if the crew reports are correct that they did report a complete loss of MGB oil pressure, LAND IMMEDIATELY was their option
There seems to be statements from certain areas that the crew was possibly under the idea that the gearbox did have a run dry capability and therefore proceeded under this assumption. I don't think it serves the crew very well for this kind of conjecture to be running rampant. I would find it hard to believe, that with their knowledge of the aircraft they would continue flight, thinking that they had 30 mins remaining, especially with the return distance to a shore point.
I just think that we should give them the benefit of the doubt until proven wrong.
carholme
From a post I made on another forum:
With all of the hype and media crap arguing about the "30 min run dry capability", I would suggest that everybody use caution in their interpretation of what is being discussed.
Remember one important fact. The present S92A Flight Manual does not state anywhere in the Emergency Procedures that continued 30 min flight is allowed for the type of indications this crew were faced with. This was not a BYP (Bypass) problem
From the flight manual:
If the MGB OIL PRES warning or the MGB OIL PRES caution and any of the following secondary indications of gearbox
failure are observed:
MGB oil pressure below 5 psi
Smoke or fumes in the cabin
Any subsequent hydraulic system failure
Progressively increasing power required to maintain flight
Unusual vibrations or noises.
6. Land immediately.
Therefore if the crew reports are correct that they did report a complete loss of MGB oil pressure, LAND IMMEDIATELY was their option
There seems to be statements from certain areas that the crew was possibly under the idea that the gearbox did have a run dry capability and therefore proceeded under this assumption. I don't think it serves the crew very well for this kind of conjecture to be running rampant. I would find it hard to believe, that with their knowledge of the aircraft they would continue flight, thinking that they had 30 mins remaining, especially with the return distance to a shore point.
I just think that we should give them the benefit of the doubt until proven wrong.
carholme
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There has been at least one reference to the Oil Temperature indication, "almost certainly registering ambient' was I think the statement.
It might just be worth mentioning that the temp sensors that are used in vehicles I.E. a bulb which must be wetted with the coolant will show a reduction in temperature as the coolant runs dry and is not therefore wetting the bulb.
ambient (indicated) temp will then be much less than that which might be being generated in a major bearing, or cylinder head, that is running dry and located some distance from the bulb.
It is illogical to assume that anyone or everyone who drives a modern helicopter has had the experience of driving a water cooled vehicle which has had a hole in the radiator and exhibited this characteristic, or, indeed been briefed of the idea.
Therefore it is logical that, if the temp sensor needs to be wetted with the coolant oil to register the temp inside the xmon in this aircraft, that the crew may have seen a low temp indication and thus been fooled into thinking that indeed there must still be oil there because it is now showing a cooler temperature.
Even the investigators of the voice comments on the CVR may not be aware of this characteristic and if not it may help them understand comments that may seem out of place. Like "look at that, ok, power up".
If that were the case a simultaneous recorded lower oil temp on the data recorder may be the nub of an explanation.
May be?
all the best tet.
It might just be worth mentioning that the temp sensors that are used in vehicles I.E. a bulb which must be wetted with the coolant will show a reduction in temperature as the coolant runs dry and is not therefore wetting the bulb.
ambient (indicated) temp will then be much less than that which might be being generated in a major bearing, or cylinder head, that is running dry and located some distance from the bulb.
It is illogical to assume that anyone or everyone who drives a modern helicopter has had the experience of driving a water cooled vehicle which has had a hole in the radiator and exhibited this characteristic, or, indeed been briefed of the idea.
Therefore it is logical that, if the temp sensor needs to be wetted with the coolant oil to register the temp inside the xmon in this aircraft, that the crew may have seen a low temp indication and thus been fooled into thinking that indeed there must still be oil there because it is now showing a cooler temperature.
Even the investigators of the voice comments on the CVR may not be aware of this characteristic and if not it may help them understand comments that may seem out of place. Like "look at that, ok, power up".
If that were the case a simultaneous recorded lower oil temp on the data recorder may be the nub of an explanation.
May be?
all the best tet.
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I haven't read the preceding 18 or so pages so forgive me if this has already been answered.
If the S92 was certified with an exception to the 30 minute rule because the "likleyhood" of a failure was "extremely remote" then my question is this:
Since there have been two failures (That I'm aware of) in five years it would seem that the "extremely remote" condition is no longer met. If this is the case then are there not grounds for suspending the type certificate or at least restricting it. No overwater flight, for instance.
I live in St.John's and saw a Cougar S92 flying a couple of days ago. Nice to see them back at it but I can't help wondering just how comfortable the pilots are at this point. Also, of course, the rig workers.
If the S92 was certified with an exception to the 30 minute rule because the "likleyhood" of a failure was "extremely remote" then my question is this:
Since there have been two failures (That I'm aware of) in five years it would seem that the "extremely remote" condition is no longer met. If this is the case then are there not grounds for suspending the type certificate or at least restricting it. No overwater flight, for instance.
I live in St.John's and saw a Cougar S92 flying a couple of days ago. Nice to see them back at it but I can't help wondering just how comfortable the pilots are at this point. Also, of course, the rig workers.
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Hmmmm...just got this from our local newspaper.
Sikorsky Aircraft Corp. says no “run dry” requirement is necessary for certifying civilian helicopters “as described in media reports.”
Sikorsky spokesman Paul Jackson said in an e-mail that the S-92A is “fully compliant with the lubrication system failure requirement” of the U.S. Federal Aviation Regulations (FAR).
The Globe and Mail reported Monday that the S-92A — the same model helicopter that crashed off Newfoundland March 12 killing 17 people — failed a key safety test.
That test, known as a run-dry requirement, determines whether the aircraft can keep flying if the oil in its main gearbox leaks out.
Sikorsky says a bypass switch in the S-92A allows pilots to capture the remaining oil if there is a leak.
It must be switched on within five seconds of noticing a drop in oil pressure.
“The aircraft has a bypass system that isolates leaks and re-circulates oil in the main gearbox once activated by the crew,” Jackson said in an e-mail.
“This system was certified by the (U.S.) Federal Aviation Authority as meeting the lubrication system failure requirements and was accepted by Transport Canada and EASA.”
EASA is the European Aviation Safety Agency.
“While the investigation into the Cougar S-92A accident continues, we cannot disclose any details that may be pertinent to the investigation. Sikorsky, however, takes exception to the characterization that the helicopter failed to meet any FAR 29 requirement,” continued Jackson.
So: Is the "run dry requirement" not a requirement after all? And how does the crew "notice" a drop in oil pressure? Aural warning, master caution? 5 seconds doesn't seem like a long time when it could be an indication problem, for instance.
Sikorsky Aircraft Corp. says no “run dry” requirement is necessary for certifying civilian helicopters “as described in media reports.”
Sikorsky spokesman Paul Jackson said in an e-mail that the S-92A is “fully compliant with the lubrication system failure requirement” of the U.S. Federal Aviation Regulations (FAR).
The Globe and Mail reported Monday that the S-92A — the same model helicopter that crashed off Newfoundland March 12 killing 17 people — failed a key safety test.
That test, known as a run-dry requirement, determines whether the aircraft can keep flying if the oil in its main gearbox leaks out.
Sikorsky says a bypass switch in the S-92A allows pilots to capture the remaining oil if there is a leak.
It must be switched on within five seconds of noticing a drop in oil pressure.
“The aircraft has a bypass system that isolates leaks and re-circulates oil in the main gearbox once activated by the crew,” Jackson said in an e-mail.
“This system was certified by the (U.S.) Federal Aviation Authority as meeting the lubrication system failure requirements and was accepted by Transport Canada and EASA.”
EASA is the European Aviation Safety Agency.
“While the investigation into the Cougar S-92A accident continues, we cannot disclose any details that may be pertinent to the investigation. Sikorsky, however, takes exception to the characterization that the helicopter failed to meet any FAR 29 requirement,” continued Jackson.
So: Is the "run dry requirement" not a requirement after all? And how does the crew "notice" a drop in oil pressure? Aural warning, master caution? 5 seconds doesn't seem like a long time when it could be an indication problem, for instance.
BB
If you are referring to the Peter Cheney article, "Doomed helicopter failed vital safety test, files reveal", then I’d have to say that I found it generally misleading.
Sikorsky won the Canadian Maritime Helicopter Project (MHP) bidding the MH-92 (Formally H-92) NOT the S-92. The Canadian Military CH-148 Cyclone (MH-92) and its systems - including the main transmission oil system – are a far cry from those certified on the Civil S-92, but hey, that wouldn’t make for a great story would it.
There have been 4 Puma accidents in only the first 3-months of this year (three of which crashed into the sea and 3 of which resulted in fatalities), but in spite of this and without a completed Air Accident Investigation Report as to the reasons for any of these or the one in question on this thread, some seem intent solely on demonising this manufacturer prior to the conclusion of any detailed investigation of all the events that led up to the final moments.
Whatever blame is attributed to this tragic accident, I’ve no doubt that there will be some serious soul searching going on within the industry and we can only hope that changes for the better will come as a result.
If you are referring to the Peter Cheney article, "Doomed helicopter failed vital safety test, files reveal", then I’d have to say that I found it generally misleading.
Sikorsky won the Canadian Maritime Helicopter Project (MHP) bidding the MH-92 (Formally H-92) NOT the S-92. The Canadian Military CH-148 Cyclone (MH-92) and its systems - including the main transmission oil system – are a far cry from those certified on the Civil S-92, but hey, that wouldn’t make for a great story would it.
There have been 4 Puma accidents in only the first 3-months of this year (three of which crashed into the sea and 3 of which resulted in fatalities), but in spite of this and without a completed Air Accident Investigation Report as to the reasons for any of these or the one in question on this thread, some seem intent solely on demonising this manufacturer prior to the conclusion of any detailed investigation of all the events that led up to the final moments.
Whatever blame is attributed to this tragic accident, I’ve no doubt that there will be some serious soul searching going on within the industry and we can only hope that changes for the better will come as a result.
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Hi Hilife: Thanks for responding to my query. (And thanks to other posters here. I am learning a few things.)
The story you refer to was yesterday's Globe story. You should look also at today's. The reporters certainly believe the gearboxes on the two machines are at least similar, and they quote a company spokesman today who leaves that impression. If you know that they are substantially different, you might want to email Peter Cheney. Reporters appreciate that kind of input. As a reporter, you often have to pick up expertise as you go along. You do your best, but sometimes it is a scramble, more so now than when I was in the business because of declining resources.
The story you refer to was yesterday's Globe story. You should look also at today's. The reporters certainly believe the gearboxes on the two machines are at least similar, and they quote a company spokesman today who leaves that impression. If you know that they are substantially different, you might want to email Peter Cheney. Reporters appreciate that kind of input. As a reporter, you often have to pick up expertise as you go along. You do your best, but sometimes it is a scramble, more so now than when I was in the business because of declining resources.
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Originally Posted by Hilife
There have been 4 Puma accidents in only the first 3-months of this year (three of which crashed into the sea and 3 of which resulted in fatalities)
I/C