S92 "unexpected control responses"
Holy sh*t!!!!!! Boy were those guys lucky. Does their diary read: note to self, if in doubt there is no doubt - shut down and get it checked?
Interesting that HUMS showed out of limits before the flight commenced but this wasn't picked up.
Surely some kind of automatic 'red light' should pop up on the HUMS interface as opposed to relying on someone going in to check every single possible parameter for exceedances?
Surely some kind of automatic 'red light' should pop up on the HUMS interface as opposed to relying on someone going in to check every single possible parameter for exceedances?
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Why the delay?
Special Bulletin out from AAIB: https://assets.publishing.service.go...017_G-WNSR.pdf
The Sikorsky S-92, like its competitor the AH H225, is a good modern aircraft with a safety record well ahead of many of its predecessors. However, I do not think it is so perfect that it can sustain the pressure of being the sole or main large helicopter in O&G crew change. If it is doing most of the work then it will have most of the accidents. There needs some solution that spreads the load before that scenario plays out in the most frightening way.
Agree, this should have been treated as a catastrophic loss right from the start for investigation purposes. It was only extreme luck and crew reactions that prevented loss of life.
A few years ago I was taken to task for suggesting a cockpit warning regarding excedances, & told that pilots would not be able to understand the data, seems the engineers have only a loose grasp as well.
As FC80 says & I suggested
Interesting that HUMS showed out of limits before the flight commenced but this wasn't picked up.
Surely some kind of automatic 'red light' should pop up on the HUMS interface as opposed to relying on someone going in to check every single possible parameter for excedances ?
As FC80 says & I suggested
Interesting that HUMS showed out of limits before the flight commenced but this wasn't picked up.
Surely some kind of automatic 'red light' should pop up on the HUMS interface as opposed to relying on someone going in to check every single possible parameter for excedances ?
500e - I actually noticed after I posted that there is a footnote in the report that basically says that there is an upgraded HUMS groundstation available that automatically flags up any problems but this version wasn't being used.
It does seem like a rather large hole in the Swiss cheese to not have had that from the beginning. I've seen some of the kind of data HUMS spits out and it's not (as far as a stupid pilot like me is concerned at least) always easy to interpret.
Huey - no, HUMS parameters are downloaded to a data card which is then removed from the A/C at the end of the flight and downloaded again onto an engineering groundstation. Live streaming would be impractical and hugely expensive right now I'd imagine.
It does seem like a rather large hole in the Swiss cheese to not have had that from the beginning. I've seen some of the kind of data HUMS spits out and it's not (as far as a stupid pilot like me is concerned at least) always easy to interpret.
Huey - no, HUMS parameters are downloaded to a data card which is then removed from the A/C at the end of the flight and downloaded again onto an engineering groundstation. Live streaming would be impractical and hugely expensive right now I'd imagine.
Certainly in the big jet world, things have moved on a touch. Quick Access Recorders for FDM have been replaced by Wireless Ground Links (commonly known as WiGgLes) triggered by weight on wheels and/or shutdown. Anywhere with wifi internet or data SIM connectivity means a data packet is automatically transferred per sector. Granted on Rotors Running rig turnrounds that doesn't give much time, but by the time of the next landing critical info could be conveyed. All of course assuming the important "criticial event" triggers are set up and the home base station has full analytical capability. Not quite real time but better than end of working day download.
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2016-24-51
As a PAX I'm surprised that an operator would "miss" a HUMS threshold exceedance on the TRPCS, especially in light of the previously issued AD # 2016-24-51, dated November 18, 2016.
I appreciate that the aircraft can only be designed and operated within budget constraints, but a TR failure on an approach to a helideck is not very conducive to the drivers or SLF. What price do the operators really place on safety...
The fact that this failure mode appears to have surfaced several times before, and with it being such a critical part of the machine's airworthiness, would have IMO warranted a much more higher profile and proactive maintenance and inspection regime, including HUMS threshold monitoring.
We have been relying on this type to get to work since 2006 over here in Newfoundland, we had CGR491 on March 12, 2009 which could have been avoided if the failure mode from Broome in July 2008 had been correctly diagnosed and an AD for immediate stud change out applied. I sincerely hope that lessons are learned here this time round, as somebody earlier had said this was a large hole in the Swiss cheese.
I appreciate that the aircraft can only be designed and operated within budget constraints, but a TR failure on an approach to a helideck is not very conducive to the drivers or SLF. What price do the operators really place on safety...
The fact that this failure mode appears to have surfaced several times before, and with it being such a critical part of the machine's airworthiness, would have IMO warranted a much more higher profile and proactive maintenance and inspection regime, including HUMS threshold monitoring.
We have been relying on this type to get to work since 2006 over here in Newfoundland, we had CGR491 on March 12, 2009 which could have been avoided if the failure mode from Broome in July 2008 had been correctly diagnosed and an AD for immediate stud change out applied. I sincerely hope that lessons are learned here this time round, as somebody earlier had said this was a large hole in the Swiss cheese.
What value is data when ignored?
As mentioned earlier two bad events occurred post detection by HUMS equipped aircraft, yet each aircraft was signed off as "Serviceable".
As a perfect helicopter is impossible to design,build, and maintain...there needs to be a detection system to assist in ensuring faults being found and reported ergo HUMS being invented and incorporated into modern Helicopters.
What good is HUMS if its successful detection of a problem is not properly used in a timely fashion?
Half assed measures undo every Safety Program.
HUMS alone is not the last word on the airworthiness of an aircraft but it sure goes a long way in making such a determination.
Why can HUMS not be modified to provide a Cockpit warning of some kind should a fault situation be detected?
Why can the ground station not be modified so that n immediate fault message not be provided in real time to Engineering?
If airlines can live stream engineering data the it would seem the helicopter industry could do the same in specialized operations such as the North Sea and Gulf of Mexico?
Yes....that costs money....probably a lot of money....but at what point does those costs are offset by preventing aircraft losses that kill a dozen or more people per event?
As a perfect helicopter is impossible to design,build, and maintain...there needs to be a detection system to assist in ensuring faults being found and reported ergo HUMS being invented and incorporated into modern Helicopters.
What good is HUMS if its successful detection of a problem is not properly used in a timely fashion?
Half assed measures undo every Safety Program.
HUMS alone is not the last word on the airworthiness of an aircraft but it sure goes a long way in making such a determination.
Why can HUMS not be modified to provide a Cockpit warning of some kind should a fault situation be detected?
Why can the ground station not be modified so that n immediate fault message not be provided in real time to Engineering?
If airlines can live stream engineering data the it would seem the helicopter industry could do the same in specialized operations such as the North Sea and Gulf of Mexico?
Yes....that costs money....probably a lot of money....but at what point does those costs are offset by preventing aircraft losses that kill a dozen or more people per event?
SASless: are you familiar with the opposite problems in HUMS, false positives? My experience (about 2 decades ago) with a much older version of a system like the HUMS was plagued by that. I am not sure what the current state of play is with HUMS and various similar systems, but let's not pretend that it offers omniscience.
Look at the human factor here: if a given HUMS type of system is low confidence as perceived by the people using it, then there is ample opportunity for their frustration with such a system to believe that yet another false positive has confronted them.
Not saying that this is the case regarding this incident, nor the previous loss in Norway, but it's a human factor that should not be swept under the rug.
Look at the human factor here: if a given HUMS type of system is low confidence as perceived by the people using it, then there is ample opportunity for their frustration with such a system to believe that yet another false positive has confronted them.
Not saying that this is the case regarding this incident, nor the previous loss in Norway, but it's a human factor that should not be swept under the rug.
Non-Driver - for the sake of argument, what you're suggesting re. downloading via WiFi/4G every time the aircraft touches down at home base wouldn't offer any improvement on the current frequency of HUMS checking - I believe every operator in the NS now dowloads the data before every flight - including rotors running turnarounds. 
at what point does those costs are [sic] offset by preventing aircraft losses that kill a dozen or more people per event?
No room left under the rug with this one since the same thing happened with the pilots and the aircraft behaviour. They were presented with what we now know was evidence of impending failure but in the circumstances they were able to assure themselves that the effect was typical of local air conditions.
