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S92 "unexpected control responses"

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S92 "unexpected control responses"

Old 14th Apr 2018, 12:26
  #201 (permalink)  
 
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Chance,

Perhaps I wasn’t clear enough earlier.

My point was meant to be...a Pilot had to use full yaw control input in conditions not requiring such extreme input in an aircraft generally accepted as having excellent amounts of tail rotor authority.

I would think a proper reaction to that singularity would have been along the lines of....”Whoa...what the heck just happened!” followed by some discussion with his Crew Mate along the lines of “Did you see that?”.

When your flight controls noticeable differ from normal inputs for any given situation there should be some healthy concern.

What I am describing is analogous to a sudden onset of an unusual vibration while inflight....if you notice the change....you should consider the source and implications resulting from that unusual event.
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Old 15th Apr 2018, 00:05
  #202 (permalink)  
 
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Originally Posted by chance it View Post
All of your statement doesn’t detract from what I said ...it was a lot more serious than an ‘unexpected control response’ , and had it happened away from a landing site could have had a very different ending .
Apate , for negativity read realism. It seems ok to berate the Puma on this forum but to even question the S92 one gets accused of being drunk ?
I agree with you. IMHO, it was at least a lost of tail rotor control (if we assume the power increase for landing occured well before the bearing total collapse -because they were already over the helideck at 4ft- and the sharp yaw to the right, we can think on lost of thrust as well, despite the report stating it was not). And yes, it could have been a disaster. And yes, the 92 is subject to failures.
Reading other threads, I also noticed a "225 vs 92" tendency on posts. I fly the S92 and feel safer than if I was flying the 225, what I could do without problem if required to.
Maybe the magnitude of the failure, as said before, and the manufacturer way of dealing with situations like these make people (not just some pilots) think this way.
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Old 15th Apr 2018, 06:34
  #203 (permalink)  
 
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I said LAND, not DITCH it.
Great, 100nm from the nearest land or offshore site and the light comes on.

The 225 did have a similar light though with the "temporary" gearbox shaft fix in 2012-13 which allowed 30mins flight at Vy.
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Old 15th Apr 2018, 11:24
  #204 (permalink)  
 
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Except that a hums warning is generally found at base after landing is it not? I admit I haven't flown a heavy since may 2016 so please disregard if things have moved on since then.

Si
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Old 17th Apr 2018, 06:42
  #205 (permalink)  
 
Join Date: Jun 2016
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In the early days of the S92, a Norsk Helikopter crew experienced the same failure enroute to Bergen. They treated it the way they were used to trough their simulator training/OPCs and did a perfect running landing accordingly in Bergen.
I believe the focus we have in Norway on using simulators for training and not only checking, is the right way to building experience/confidence among the crews.
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Old 17th Apr 2018, 20:36
  #206 (permalink)  
 
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What is missing from HUMS is something that we wanted to have when it first started in the 1980s. A light in the cockpit which would say.

DO NOT FLY THIS HELICOPTER
or
LAND AS SOON AS POSSIBLE
The problem is that there is a huge gulf in certification between software taking measurements in flight that will be downloaded on the ground for analysis by engineers/computers to make an "it would be a good idea to manually check this bit of the aircraft" decision, and software that takes measurements in the air to present an indication to the pilot as to whether to continue flight or not. A huge gulf.

HUMS is predicated on the situation that there is sufficient time between a degradation becoming detectable and the subsequent failure of a component, that download of the data and ground analysis of it will detect the former before the latter. Trying to put general-purpose measurement and analysis functions onto the aircraft such that the result is instantly available to the pilot as a 'land NOW' indication is not only expensive, but it is hard. There are numerous false positives that could, conceivably, cause aircraft (and people) to be lost due to Land Immediately alerts that are wrong.

Given the general assumption within the use-case of HUMS, it is not actually a good vehicle for flight deck alerts - it is an indicator to an engineer that there could be a problem with a particular part of the aircraft and hence that should be checked. It is up to those checks to determine whether the aircraft should fly or not.

If there is a specific failure case where the time between a degradation being measurable and the subsequent failure occurring is too short for the 'standard' HUMS turnaround then there is a very good case for developing and installing systems to measure and alert on that specific situation. These would be developed to the appropriate certification level and the results (hopefully) be trustworthy enough to present on the flight deck.
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Old 18th Apr 2018, 08:00
  #207 (permalink)  
 
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Trying to put general-purpose measurement and analysis functions onto the aircraft such that the result is instantly available to the pilot as a 'land NOW' indication is not only expensive, but it is hard
And essentially is showing that HUMS is not doing the job it's intended to do (as you describe).
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Old 18th Apr 2018, 11:32
  #208 (permalink)  
 
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Is my impression that HUMS is doing its job....but the Human Interface is causing the failures to effectively warn the Pilots that result in tragedies?

It seems the required response to the output of the HUMS systems has been lacking in several of the events.

It takes effective, timely, and accurate interpretation of the Data to complete the Loop on HUMS and what is expected of it.
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Old 18th Apr 2018, 12:15
  #209 (permalink)  
 
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Beware

Every ‘aid’ to assist decision making is welcome but -
On one hand we bemoan the increasing automation of flying and the consequential degrading of flying skills - on the other hand we stress the importance of ‘captaincy’.
However we all know that companies only like demonstrations of ‘captaincy’ when it does not affect the schedule or bottoms line.
The crew had ample indications that this flight should have stopped way before they ‘manfully’ kept it on the deck. Unexpected requirement for full opposite pedal FFS!
Hums appears great and is as good as the engineer interpreting the data - by all means make the data less ambiguous but please let us not forget the real failing here and where any resources should be targetted.
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Old 18th Apr 2018, 12:38
  #210 (permalink)  
 
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Originally Posted by SASless View Post
Is my impression that HUMS is doing its job....but the Human Interface is causing the failures to effectively warn the Pilots that result in tragedies?

It seems the required response to the output of the HUMS systems has been lacking in several of the events.

It takes effective, timely, and accurate interpretation of the Data to complete the Loop on HUMS and what is expected of it.
I didn't mean in general - I meant that if you had a warning in the cockpit that said 'land immediately' it would imply the HUMS wasn't doing its true role prior to that.
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Old 18th Apr 2018, 14:17
  #211 (permalink)  
 
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Like many who post here, I have considerable offshore time. Granted, it's only Gulf of Mexico time and only in relatively small ships compared to the S-92, but i'd be surprised if the wind limits overseas are much different than what we adhered to in the GOM.

That said, I can't recall a single time in 13 years of offshore flying when it was required that i put in FULL left pedal response to a gust of wind while in a hover. Such a gust would undoubtedly produce a rolling or sliding effect in addition to the yaw. Wind over offshore platforms is seldom uniform in any respect. It's quite chaotic, especially when the velocity increases to the point that it would cause yaw excursions in a (big!) hovering helicopter much less the puny 206's and Bo-105's I flew.

Now we get to an S-92 pilot who had to push FULL left pedal to counter an uncommanded yaw. And then he took off anyway without further questioning or troubleshooting? Look, there may not have been a light on the dash that said, "Do Not Fly This Aircraft," but there sure should have been one in the minds of that crew! I mean, aren't we supposed to be the "brooding introspective anticipators of trouble" that newsman Harry Reasoner observed about us back during the days of the Vietnam War?

When did we stop that?

I think it's totally right and justified to look into the captaincy issues at play here.
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Old 18th Apr 2018, 21:04
  #212 (permalink)  
 
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Years ago in the dark ages we had In-Cockpit Blade Integrity Indicators in addition to Individual blade mounted indicators. Overtime...the Cockpit Warning Lights were removed due to spurious indications and the Blade Indicators remained.

Different technologies separated by quantum leaps in sophistication.....but similar issues in how to include the Pilot into the equation!
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Old 19th Apr 2018, 00:03
  #213 (permalink)  
 
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On the captaincy issue, I think a chunk of the problem is that the offshore industry is so brow-beaten by cuts and clients breathing down necks wanting to make a big fuss about any glitch in the service, that there is a tendency to just want to keep one’s head down and not make a fuss. Turned into bus-driving zombies if you like. One can argue that pilots shouldn’t react like that, but human nature is what it is and no point in trying to pretend otherwise.
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Old 19th Apr 2018, 06:23
  #214 (permalink)  
 
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Originally Posted by HeliComparator View Post
On the captaincy issue, I think a chunk of the problem is that the offshore industry is so brow-beaten by cuts and clients breathing down necks wanting to make a big fuss about any glitch in the service, that there is a tendency to just want to keep one’s head down and not make a fuss. Turned into bus-driving zombies if you like. One can argue that pilots shouldn’t react like that, but human nature is what it is and no point in trying to pretend otherwise.
Hear, hear.
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Old 19th Apr 2018, 10:25
  #215 (permalink)  
 
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On the captaincy issue, I think a chunk of the problem is that the offshore industry is so brow-beaten by cuts and clients breathing down necks wanting to make a big fuss about any glitch in the service, that there is a tendency to just want to keep one’s head down and not make a fuss.
well that's not the case on the contract I fly. If we stop for any potential safety related problem we get nothing but support and even praise from the clients health and safety and aviation departments
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Old 19th Apr 2018, 10:53
  #216 (permalink)  
 
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Originally Posted by Brother View Post
well that's not the case on the contract I fly. If we stop for any potential safety related problem we get nothing but support and even praise from the clients health and safety and aviation departments
I'm not surprised to hear that
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Old 19th Apr 2018, 14:57
  #217 (permalink)  
 
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Agree 212, we stress it constantly.
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Old 19th Apr 2018, 16:47
  #218 (permalink)  
 
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Originally Posted by industry insider View Post
Agree 212, we stress it constantly.
You are fortunate - as many companies stress ‘safety’ but when it comes to perceived cost savings they appear to be simple words.
Heck, one such company even has the temerity to host an annual Safety Conference, inviting the ‘Great’ and the ‘Good’! The same company in fact which threw aircraft at customers at a loss then entered Chapter 11.
Not all companies are the same of course and you guys must be some of the lucky ones but you are in a minority.
It is increasingly difficult for Accountants to regard the crew as invaluable, highly-regarded assets when so many of them behave as blinkered bus drivers, fearful for their own longevity. T&Cs are a joke for such a responsible position. The classic downward spiral of “getting what you pay for” has been costed by the bean counters and affect to financial and reputation assessed as “acceptable”.
That said, it is amazing how just one strong and knowledgeable manager in the right position can effect change for the good so keep your chin up ;-)
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Old 19th Apr 2018, 22:08
  #219 (permalink)  
 
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Originally Posted by Brother View Post
well that's not the case on the contract I fly. If we stop for any potential safety related problem we get nothing but support and even praise from the clients health and safety and aviation departments
Do the client’s health and safety and aviation departments pay the bill and sign up the contractor again at end of contract? Large oil companies are not homogeneous, there are different internal factions at play and sometimes the contractor is the piggy in the middle.
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