On Friday, September 25, 2015 at 7:45:05 PM UTC+1, Martin Eiler wrote:
I really think, from a safety point of view, that the "most critical"
lever should also be the "most obvious" lever. In my book, that's the
airbrake lever. I don't like the ergonomics of the levers you have to
rotate to be able to use.
Dan, 5J

Once while still on the ground and towing with a 182 I had a Janus A get
high and off to my left. He was high enough that I could not see his wings
in the mirror. There still being enough runway ahead for him to safely
land, I released the glider and the pilot safely landed in the dirt to the
left of the runway. When I got back on the ground and spoke with the
pilot. He admitted that he had taken off in negative flaps with his left
hand off of the flap handle then when he reached to go positive with the
flaps he mistakenly grabbed the spoiler handle. He said the glider didn't
feel normal but he was confused and didn't know what was wrong. As happens
far too often the pilot was tunnel visioned to the degree that he was
incapable of figuring out what was wrong and correcting it. An additional
disappointing aspect was the fact that his front seat passenger, who was
also a pilot saw what he was doing wrong but made no attempt to tell the
other pilot. In airline terms this is called a failure of cockpit resource
management.

This thread was initiated because a simple mistake that could easily have
been corrected, eventually led to a crash. The real cause of this accident
like so many others, was tunnel vision. Which may have started sometime
prior to the pilot mistakenly grabbing the gear handle. Rest assured this
pilot did not intend to grab the gear handle nor make multiple passes at
landing and of course he did not realize he was getting so slow that he was
going to stall/spin.

Until someone in higher authority like the NTSB or FAA decides that tunnel
vision is a root cause of far too many aviation accidents and initiates an
extensive study of it's causes, effects and all possible corrective
actions.
We will continue to hear accidents were the result of dehydration,
distraction, medical issue or the catch all, pilot error. I would like to
believe a meaningful study will be conducted in my life time, but after 50
years in aviation I seriously doubt it.

If I am ever killed in a glider accident, I honestly encourage all pilots
to use it as an opportunity to openly and seriously discuss accidents and
issues of safety. A year later when the NTSB report is published the
accident will have long faded from almost everyone's memory.

As an alternative description to "tunnel vision" I like the concept of the decision tree. We continually have choices (eg which lever to grab and then whether or not to do it without visually checking) and make a decision which may be wrong through carelessness or poor judgement. At that point we have taken one of two or more branches of the decision tree. If things don't work out as expected we may make another choice (e.g. start using the pitch control) and then find that control isn't responding as usual - so we make another decision that may help or may not help (e.g. choose to release or not release from tow) etc. etc.

The one thing we are demonstrably poor at in times of stress is mentally backing our way down the decision tree and considering at which step we may have made a wrong decision upon which all the other wrong decisions followed..

Tunnel vision on its own is a description that doesn't (for me) naturally lead to a mental process to correct things whereas if we hold the concept of the decision tree in the front of our mind then it gives us an easily understood mental technique that we can apply to very quickly reverse check our recent actions (and so escape the tunnel vision).

Unfortunately not all decisions are reversible once taken.

John Galloway