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Old December 10th 19, 12:10 AM posted to rec.aviation.soaring
Bob T
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Posts: 38
Default Gliding risk....

On Saturday, December 7, 2019 at 3:09:19 AM UTC-7, krasw wrote:
Reading this forum, sounds like biggest safety risks in gliding a

- Any glider or radio that has had an AD in it's history
- Rogue thermals
- Mysterious medical symptoms that occur only when flying

Other that that, we are pretty safe.


Regarding the rogue thermal comment... they can occur. I came VERY close to becoming a statistic a few years ago while thermalling about 1500 ft. agl and wrote a feature article for SOARING MAGAZINE dealing with it. Rather than stalling an inside wing in a thermal turn (as one would expect if you happened to fly too slowly), while thermalling at about 10-15 kts above stall speed my INSIDE (lower) wing suddenly was pushed up and over, resulting in a steep dive / spiral. Subsequent research showed that some thermals can have strong down cores inside of overall lift, and if a glider happened to hit the sheer boundary, with suddenly one wing in the up air and the other in the down air, your day could quickly end.

See https://www.danlj.org/~danlj/Soaring...b_Thompson.pdf

and Dr. Dan Johnson had a good one, too https://www.danlj.org/~danlj/Soaring...Jan-p12-15.pdf

There are 2 books I referred to in my classes that have some pretty good info, too, although they are mostly intended for business folks:
1. Will Your Next Mistake Be Fatal? by Robert E. Mittelstaedt, Jr. for example - on page 160 - Insight #29 - Culture is powerful - what creates success may kill you. Think about this one seriously, for a long time! What you, or others, have gotten away with for a number of times can lead to complacency... and you becoming a statistic... that you couldn't tell anyone about ... from the grave. I recently attended a "celebration of life" for a friend that I suspect may have either lost his life due to his prior successes or rogue air.
2.Why We Make Mistakes by Joseph T. Hallinan