Normalisation of deviance
Moderator
Thread Starter
I don't fly rotary, but do fly both 3-axis and flexwing microlights, and light aeroplanes.
Going from 3-axis anything to a flexwing I find as difficult as getting out of my car and onto a bicycle. That is to say, not at-all.
I have concerned myself occasionally, although not made any serious mistakes thankfully, going between 3-axis microlights and larger light aeroplanes as whilst the controls work basically the same, the speeds, heights and attitudes are all different.
G
Going from 3-axis anything to a flexwing I find as difficult as getting out of my car and onto a bicycle. That is to say, not at-all.
I have concerned myself occasionally, although not made any serious mistakes thankfully, going between 3-axis microlights and larger light aeroplanes as whilst the controls work basically the same, the speeds, heights and attitudes are all different.
G
Join Date: Oct 2001
Location: Vancouver Island
Posts: 2,517
Likes: 0
Received 0 Likes
on
0 Posts
My reason for bringing this up is that here in Canada the system is breeding generations of pilots who are brain washed into thinking that unless you have a PPC check ride and the paper work to show you have a given type of airplane on your existing license you can not fly that type commercially, hence we have one or two trick ponies who believe flying a new type of airplane is some kind of black magic that requires you have paper work to fy it.
Now don't get me wrong here, I have no problem with pilots who believe that it is best for them to jump through more and more hoops to be blessed by the bureaucracy that controls their ability to fly for a living. Knowing your limitations is perfectly fine.
I came from a different mindset where if we could demonstrate to a company chief pilot that we knew the limitations and pilot operating instructions for a given airplane and then demonstrated we actually could fly it we could then go to work for that company.
Of course we had to show that our license covered that type and class of airplane, for instance we held a ATPL if we were applying for transport category airplanes.
Now don't get me wrong here, I have no problem with pilots who believe that it is best for them to jump through more and more hoops to be blessed by the bureaucracy that controls their ability to fly for a living. Knowing your limitations is perfectly fine.
I came from a different mindset where if we could demonstrate to a company chief pilot that we knew the limitations and pilot operating instructions for a given airplane and then demonstrated we actually could fly it we could then go to work for that company.
Of course we had to show that our license covered that type and class of airplane, for instance we held a ATPL if we were applying for transport category airplanes.
'Deviance normalisation' are fine, sophisticated-sounding words, but wouldn't 'bad habits' do just as well?
Even better is just to describe the issue at hand rather than using such a label (the basis of Sidney Dekker's rationale in many ways) in the first place. Long checklists aren't ergonomic to use and probably contain many items which rarely (if ever) change state. Over a long time (years perhaps) the crew probably gradually omitted more and more of the 'static' items until they ended up with three actions: fire it up, taxi out and take-off.
Unless I missed it, one thing the report doesn't really mention is time - I would expect rushed or omitted checks to be partly driven by time pressure. If this was the case it may help explain the lateness of the t/o abort although many factors could have equally contributed to it.
Whatever the case, it's a very alarming occurrence which was completely avoidable and particularly harrowing, given that all souls survived the initial impact.
Last edited by Ridger; 5th Jan 2016 at 10:57.
Join Date: Jan 2009
Location: Oxford, UK
Posts: 1,546
Likes: 0
Received 0 Likes
on
0 Posts
CB SIFT CB E. only a glider. but this list is graven (or beaten) into the brain of every student pilot.
Controls - Full and Free.
Ballast - weight and balance correct
Straps - securely fastened
Instruments - working and set
Flaps (if fitted) - set for takeoff
Trim - set for airspeed in case of launch failure
Canopy - closed and locked
Brakes - airbrakes in this case, not wheelbrakes
Eventualities - your plan of what to do in case of launch failure
When you have completed this memorised check list, then you may accept the launch cable, whether airtow or winch. The club member on the wingtip will check that above and behind is clear to go. The signal, by radio or by arm for takeoff is given to the tug pilot or the winch driver. Then up you go!
For all that, I had to stop a launch when I was only a beginner holding the wingtip; the highly experienced chairman of the gliding club still had the gust locks on his wings...........the rule is that anyone may STOP a launch if you see danger.
Controls - Full and Free.
Ballast - weight and balance correct
Straps - securely fastened
Instruments - working and set
Flaps (if fitted) - set for takeoff
Trim - set for airspeed in case of launch failure
Canopy - closed and locked
Brakes - airbrakes in this case, not wheelbrakes
Eventualities - your plan of what to do in case of launch failure
When you have completed this memorised check list, then you may accept the launch cable, whether airtow or winch. The club member on the wingtip will check that above and behind is clear to go. The signal, by radio or by arm for takeoff is given to the tug pilot or the winch driver. Then up you go!
For all that, I had to stop a launch when I was only a beginner holding the wingtip; the highly experienced chairman of the gliding club still had the gust locks on his wings...........the rule is that anyone may STOP a launch if you see danger.
Join Date: Jun 2008
Location: Estonia
Posts: 140
Likes: 0
Received 0 Likes
on
0 Posts
I've written up the accident here:
Fear of Landing ? How to Drop a Gulfstream IV into a Ravine: Habitual Noncompliance
I think the most telling aspect was not just that they routinely skipped the pre-flight checks but that having discovered that the throttle was being limited, they tried to solve the issue while continuing the take-off run.
Fear of Landing ? How to Drop a Gulfstream IV into a Ravine: Habitual Noncompliance
I think the most telling aspect was not just that they routinely skipped the pre-flight checks but that having discovered that the throttle was being limited, they tried to solve the issue while continuing the take-off run.
Join Date: May 2002
Location: Permanently lost
Posts: 1,785
Likes: 0
Received 0 Likes
on
0 Posts
There was lurking on this forum about a month ago a link to a very interesting article on normalisation of deviance written by an RAF Tornado pilot. It was so interesting that I lifted it and included it in a safety newsletter for the pilots in the company that I work for.
The article referenced the Challenger and Columbia crashes as well as the G4 crash referred to in the OP but the primary interest was in his own tale of very, very nearly smashing a Tornado into the ground while trying to raise the undercarriage.
He was on a NATO deployment at the time engaged in an exercise in Belgium. All was fine until one day the undercarriage refused to lock up. The inspection showed a severely worn part that wouldn't let the undercarriage lock up. It couldn't be fixed. However, and this is where the deviation started, the pilot thought that if he slightly bunted the jet after takeoff thereby creating some negative g the undercarriage might lock up and the exercises could be continued. It worked.
However, during the week the weather worsened requiring more extreme handling to get the gear up (it took about 10 sec to cycle and there were speed limitations on the u/c). It all came to a head on the day they were to return to the UK when it went pear shaped as the cloud base was the lowest it had been. The aircraft wound up heading for the ground outside of the ejection parameters and was only saved by some extremely quick thinking. A very chastened crew then flew the aircraft back to the UK with the u/c down.
What he wanted to emphasise was that the deviation initially was not great but that it gradually grew as the week progressed and the weather worsened. The deviation had worked initially without problem so perhaps some further deviation will work without problem. And this is the rub, its more likely to be found the more experienced the crew.
They are the ones more likely to cut a corner because they have done it in the past without a problem and thus the deviation gets larger. That G4 crew were experienced and the NTSB report notes that on the recurrency training they did everything by the book but the flight data recorder noted that it was common practice for them not to do the pre-takoff checks at all. It had worked for all those times before why shouldn't it work this time?
I discussed the article with the CFI of the company I work for and he admitted to being guilty of it in the past and spoke about that occasion. He subsequently pulled himself up for his lapse and is well aware of the danger. We also had an example of a check-list not been done in circumstances where there was enormous pressure on the pilot to get going (weather, last light etc.). He neglected something that very nearly was fatal.
Want another example, the Costa Concordia. The company navigation plan called for (I think) a 5 mile distance from the island. That had been progressively lessened by the ships crew, all without problem until, of course, that night. Normalisation of deviance at its best.
I get the impression from reading some of the posts here that people think it can't/wouldn't happen to them. I beg to disagree; it can happen to the best of pilots when complacency becomes a factor.
The article referenced the Challenger and Columbia crashes as well as the G4 crash referred to in the OP but the primary interest was in his own tale of very, very nearly smashing a Tornado into the ground while trying to raise the undercarriage.
He was on a NATO deployment at the time engaged in an exercise in Belgium. All was fine until one day the undercarriage refused to lock up. The inspection showed a severely worn part that wouldn't let the undercarriage lock up. It couldn't be fixed. However, and this is where the deviation started, the pilot thought that if he slightly bunted the jet after takeoff thereby creating some negative g the undercarriage might lock up and the exercises could be continued. It worked.
However, during the week the weather worsened requiring more extreme handling to get the gear up (it took about 10 sec to cycle and there were speed limitations on the u/c). It all came to a head on the day they were to return to the UK when it went pear shaped as the cloud base was the lowest it had been. The aircraft wound up heading for the ground outside of the ejection parameters and was only saved by some extremely quick thinking. A very chastened crew then flew the aircraft back to the UK with the u/c down.
What he wanted to emphasise was that the deviation initially was not great but that it gradually grew as the week progressed and the weather worsened. The deviation had worked initially without problem so perhaps some further deviation will work without problem. And this is the rub, its more likely to be found the more experienced the crew.
They are the ones more likely to cut a corner because they have done it in the past without a problem and thus the deviation gets larger. That G4 crew were experienced and the NTSB report notes that on the recurrency training they did everything by the book but the flight data recorder noted that it was common practice for them not to do the pre-takoff checks at all. It had worked for all those times before why shouldn't it work this time?
I discussed the article with the CFI of the company I work for and he admitted to being guilty of it in the past and spoke about that occasion. He subsequently pulled himself up for his lapse and is well aware of the danger. We also had an example of a check-list not been done in circumstances where there was enormous pressure on the pilot to get going (weather, last light etc.). He neglected something that very nearly was fatal.
Want another example, the Costa Concordia. The company navigation plan called for (I think) a 5 mile distance from the island. That had been progressively lessened by the ships crew, all without problem until, of course, that night. Normalisation of deviance at its best.
I get the impression from reading some of the posts here that people think it can't/wouldn't happen to them. I beg to disagree; it can happen to the best of pilots when complacency becomes a factor.
Last edited by PLovett; 29th Mar 2016 at 04:11.
Join Date: Jun 2002
Location: Wor Yerm
Age: 68
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Practical Drift
Bad habits would be a term given by punitive managers trying to make a point rather than trying to fix the problem. Because too often the problem is the system itself. And the things that make it work are the people who run it. And we are not talking about un-motivated local authority workers skiving off work because they can be bothered. I'm talking about highly motivated people who want to do nothing less than a good job. Unfortunately, they are also the people who unknowingly cross the grey margin from relatively safe to highly dangerous.
It has another name: Practical drift. It is defined as the unintentional adaptation of routine behaviors from written procedures. The occurrence of practical drift can result in a catastrophic disaster in normally highly reliable systems.
These are also the little tweaks we all put in to make a system work. We do them just to get the job done more efficiently. Things like not wearing your HiViz vest, releasing the brakes early so your friend the Disatcher can get an on-tine departure, taxiing at 35 Kts to ensure your passengers make their connections, and so on. And then sometimes we have to do them because the job as described would be impossible. I remember once that we had to release the brakes to perform a power-back and when we only when we were reversing could we start the engines. Place this particular crew in the system they operated and then think again before you start throwing rocks at them.
PM
It has another name: Practical drift. It is defined as the unintentional adaptation of routine behaviors from written procedures. The occurrence of practical drift can result in a catastrophic disaster in normally highly reliable systems.
These are also the little tweaks we all put in to make a system work. We do them just to get the job done more efficiently. Things like not wearing your HiViz vest, releasing the brakes early so your friend the Disatcher can get an on-tine departure, taxiing at 35 Kts to ensure your passengers make their connections, and so on. And then sometimes we have to do them because the job as described would be impossible. I remember once that we had to release the brakes to perform a power-back and when we only when we were reversing could we start the engines. Place this particular crew in the system they operated and then think again before you start throwing rocks at them.
PM
