Interesting Reading about Human Factors
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Interesting Reading about Human Factors
“The trouble starts when I fail to notice that I see only whatever confirms my categories and expectations but nothing else. The trouble deepens even further if I kid myself that seeing is believing. That’s wrong. It’s the other way around. You see what you expect to see.”
Karl Weick & Kathleen Sutcliffe
Managing the Unexpected
Willow Fire Report
The document is the report and findings into the fatal accident of a rapeller at the Willow Creek Helibase in California last year. While it is not "technically" an aviation accident--it was reported as such, and I am sure we can all learn something from the report---especially this piece:
The Human Factors section of the report, beginning on page 33, is particularly interesting. Written by Jim Saveland and Ivan Pupulidy, it discusses, along with other issues, the concept of not seeing elements in our visual field, or “blindness”.
As a side note---the day after the accident, there was a nationwide mandatory stand down and review of equipment and procedures. Some USFS regions chose to extend the stand down, others did not. My crew (Region 4) continued to rappel for the remainder of the season. There is rumor, (I have heard but not seen the document), that there will be no rappelling from Type III helicopters this year.
Here is a brief synopsis of what happened:
RIP Tom Marovich
Karl Weick & Kathleen Sutcliffe
Managing the Unexpected
Willow Fire Report
The document is the report and findings into the fatal accident of a rapeller at the Willow Creek Helibase in California last year. While it is not "technically" an aviation accident--it was reported as such, and I am sure we can all learn something from the report---especially this piece:
The Human Factors section of the report, beginning on page 33, is particularly interesting. Written by Jim Saveland and Ivan Pupulidy, it discusses, along with other issues, the concept of not seeing elements in our visual field, or “blindness”.
As a side note---the day after the accident, there was a nationwide mandatory stand down and review of equipment and procedures. Some USFS regions chose to extend the stand down, others did not. My crew (Region 4) continued to rappel for the remainder of the season. There is rumor, (I have heard but not seen the document), that there will be no rappelling from Type III helicopters this year.
Here is a brief synopsis of what happened:
Before the rappelling training, Marovich noticed that the Kong clip on his Tri-link was broken. The Kong Clip is used to center the “J” hook at the forward corner of the Tri-link. It is a nice piece of equipment to have, but is not essential. Kong clips are prone to breaking and are not popular. He sought assistance from a spotter trainee who replaced the Kong clip with an “O” ring, which was an authorized substitution.
The “O” ring was installed incorrectly. Before the rappelling attempt, four people looked at or inspected Marovich’s rappelling gear: the spotter trainee who installed the “O” ring, Marovich, and in the helicopter a spotter, and another helitack crewperson who did a “buddy check”.
Marovich fell, unarrested, shortly after stepping out onto the helicopter skid. He was pronounced deceased about 30 minutes later.
Here are some photos from the report showing for illustration purposes examples of a correct and then an incorrect installation of an “O” ring on a Tri-link.
Correct installation:
Incorrect installation:
The “O” ring was installed incorrectly. Before the rappelling attempt, four people looked at or inspected Marovich’s rappelling gear: the spotter trainee who installed the “O” ring, Marovich, and in the helicopter a spotter, and another helitack crewperson who did a “buddy check”.
Marovich fell, unarrested, shortly after stepping out onto the helicopter skid. He was pronounced deceased about 30 minutes later.
Here are some photos from the report showing for illustration purposes examples of a correct and then an incorrect installation of an “O” ring on a Tri-link.
Correct installation:
Incorrect installation:
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Gordy - How could someone not realise the error in the second photo and know that instead of the steel shackle taking all the weight, that the weight would be taken by a rubber o-ring. 
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Ned,
Probably the same way I "hear" my wife nagging at me but never "listen" to her! It happens in maintenance often as well unfortunately. Several people can look at a loose nut or bolt expecting to see it tight and say that it is when it is not. I always preach "rag maintenance". If you are wiping something off with a rag it doesn't just make it clean, it shows you by feel that something is not right instead of just "looking" for it.
Max
Probably the same way I "hear" my wife nagging at me but never "listen" to her! It happens in maintenance often as well unfortunately. Several people can look at a loose nut or bolt expecting to see it tight and say that it is when it is not. I always preach "rag maintenance". If you are wiping something off with a rag it doesn't just make it clean, it shows you by feel that something is not right instead of just "looking" for it.
Max
Thread Starter
Ned...
Read the report...it is very revealing....I have seen it happen, not necessarily with harnesses, but certainly watching someone preflight an aircraft.
Some more excerpts
How could someone not realise the error in the second photo and know that instead of the steel shackle taking all the weight, that the weight would be taken by a rubber o-ring.
Some more excerpts
Blindness
Research in visual attention has also revealed several ways that people don’t see what is in their visual field. This is simply how the human visual system works.
Inattentional blindness is the “looked-but-failed-to-see” effect. It occurs when attention is focused on one aspect of a scene and overlooks an object that is prominent in the visual field and is well above sensory threshold.
Change blindness is a failure to notice that something is different from what it was. Large changes to a visual scene are very likely to go unnoticed if they occur during saccades (eye movements) because visual analysis is suppressed during that time.
Research in visual attention has also revealed several ways that people don’t see what is in their visual field. This is simply how the human visual system works.
Inattentional blindness is the “looked-but-failed-to-see” effect. It occurs when attention is focused on one aspect of a scene and overlooks an object that is prominent in the visual field and is well above sensory threshold.
Change blindness is a failure to notice that something is different from what it was. Large changes to a visual scene are very likely to go unnoticed if they occur during saccades (eye movements) because visual analysis is suppressed during that time.
Wow!
However, I've also seen one guy cross-connect Hyd Lines to a Tail Rotor Servo and he had to make a real mess of them to do it. Normally the lines would run straight and parallel all the way down the Tail. The guy, I believed to be an experienced guy, had installed them wound around each other, crossed over, and he couldn't see the problem.
I suppose that's the "Human Element" we read about.
However, I've also seen one guy cross-connect Hyd Lines to a Tail Rotor Servo and he had to make a real mess of them to do it. Normally the lines would run straight and parallel all the way down the Tail. The guy, I believed to be an experienced guy, had installed them wound around each other, crossed over, and he couldn't see the problem.
I suppose that's the "Human Element" we read about.
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Gordy - Do you think its that familiarity breeds contempt scenario.
Sad that this oversight cost the guy his life. There must be some way to change this sort of oversight happening again.
Ned
Sad that this oversight cost the guy his life. There must be some way to change this sort of oversight happening again.
Ned
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The way the brain works it is easy to understand how this happens. Your brain looks for all the parts - all present - all in the right general area - everything must be fine...
I remember when doing training for my ppl, doing FREDA/down wind checks... Saying everything was in the green.
My instructor quickly coveed up the panel and asked me to
tell him the temps and fuel qty I had observed 'in the green'
I realized I had been caught with my pants down, and now extend my check to not just confirm if the needle is in the green, but what the actual value is as well.
I can see how at quick glance one could see the incorrect harness as 'in the green'.
I remember when doing training for my ppl, doing FREDA/down wind checks... Saying everything was in the green.
My instructor quickly coveed up the panel and asked me to
tell him the temps and fuel qty I had observed 'in the green'
I realized I had been caught with my pants down, and now extend my check to not just confirm if the needle is in the green, but what the actual value is as well.
I can see how at quick glance one could see the incorrect harness as 'in the green'.
Thread Starter
Birddog:
Perfect analogy---Many years ago when I used to give stage checks etc, I would pull the fuel gauge circuit breaker, and almost 90% of applicants, not notice it.
By the way---Who or what is FREDA?
Ned:
The problem was solved by having the J-hook attached to the tri-link and then the tri-link is locked and has "tell tale" stripes painted on it. It now means that rappellers have to slide the harness over their head, instead of putting it on like a jacket.
Perfect analogy---Many years ago when I used to give stage checks etc, I would pull the fuel gauge circuit breaker, and almost 90% of applicants, not notice it.
By the way---Who or what is FREDA?
Ned:
The problem was solved by having the J-hook attached to the tri-link and then the tri-link is locked and has "tell tale" stripes painted on it. It now means that rappellers have to slide the harness over their head, instead of putting it on like a jacket.
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Your brain looks for all the parts - all present - all in the right general area - everything must be fine...
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Paying lip service to checks is extremely common - its something I can guarantee everyone has done at some time or other.
Who has not found at some stage that he has just sung out the checks that he has learnt off by heart like lines from a play, but hasnt actually done the checks that they represent? Its something I have seen in myself particularly when I'm on my own, in a hurry or with a high workload, and I have to catch myself and force myself to do it again properly.
Students in the simulator I see all the time doing the same thing : "Landing gear down, 3 greens blah, blah, blah...." You have to stop them and say "Is it down? Are you sure?" and then they notice that they have a gear failure, and there were no "greens" at all.
I can only guess that exactly the same thing can happen in the back of the aircraft, and anywhere else for that matter where checks are done under any form of stress.
Who has not found at some stage that he has just sung out the checks that he has learnt off by heart like lines from a play, but hasnt actually done the checks that they represent? Its something I have seen in myself particularly when I'm on my own, in a hurry or with a high workload, and I have to catch myself and force myself to do it again properly.
Students in the simulator I see all the time doing the same thing : "Landing gear down, 3 greens blah, blah, blah...." You have to stop them and say "Is it down? Are you sure?" and then they notice that they have a gear failure, and there were no "greens" at all.
I can only guess that exactly the same thing can happen in the back of the aircraft, and anywhere else for that matter where checks are done under any form of stress.
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Not a bit unlike readback/hearback errors:
Heartbreaking seeing the incorrect installation pic.
We are all set up to hear what we expect to hear. Pilots notice this when they realize that the clearance they "heard" was not the clearance that was issued. Instead, they heard what they expected to hear. Controllers suffer the same fate.
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human factors
As I become more experienced at flying. I try to be mindful of complacency and hazardous behaviours and attitudes. More often than not, I think about new ways to save myself from myself. Does anyone recommend any articles on Human Factors or this area of study? Any links would be much appreciated
I'm not a pilot, but I read the AAIB accident reports. There are plenty of examples of ways to be caught out by yourself, your machine and the weather in them. They've taught me plenty.
Purveyor of Egg Liqueur to Lucifer
Hi rye,
You might want to read through CAP737
Guidance For Flight Crew, CRM Instructors (CRMIS) and CRM Instructor-Examiners (CRMIES)
It's a large publication, but covers a large subject.
www.caa.co.uk/docs/33/CAP737.PDF
You might want to read through CAP737
Guidance For Flight Crew, CRM Instructors (CRMIS) and CRM Instructor-Examiners (CRMIES)
It's a large publication, but covers a large subject.
www.caa.co.uk/docs/33/CAP737.PDF
Purveyor of Egg Liqueur to Lucifer
And not forgetting the Safety Evenings, covered in a thread here, that I hear are very good.
http://www.pprune.org/rotorheads/310...angements.html
http://www.pprune.org/rotorheads/310...angements.html
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Complacency research
You may want to do a search for articles by Detreich Mansey. He has done some interesting investigations in to complacency (he defines it as re-allocated attention), especially among dual-pilot crews (if I remember correctly his early trials indicated monitoring dropped to as low as 17% when a second pilot was present).
Jolly
Jolly