On 5/6/2014 5:56 PM, Don Johnstone wrote:
Major Snip...

I will stick with my
300ft thank you, I know it works. Low turns, below that height may have
been acceptable in old wooden gliders, the minimum height in T31 and T21
gliders was 150ft, but for modern glass gliders it is just far too low...
Snip...

Volunteers for testing whether a lower-speed/higher-rate glider (T21/T31
certainly qualify) requires less height to execute a course reversal compared
to a higher speed/lower-sink rate modern plastic one? While testing, please do
contact the ground in controlled flight...

...you
only have to look at the accident statistics to see that low final turns
figure to a large degree in accidents so why plan for it?

Because: a) it happens (statistics); and b) (IMO) we reasonably safely can?
(That's certainly NOT the case when practicing the inadvertent departure from
controlled flight in the pattern.) And the skill might be good to have in
one's skill set? I'm not trying to be snarky, but it's the *uncontrolled*
ground contact that jumps out from the death statistics I've seen.

I repeat a controlled descent with wings level is far more likely to have a
better result than hitting the ground in a turn or even worse spinning in
trying to avoid it.

Roger both thoughts...especially that last one!

It's not "merely" the broken rope Joe Glider Pilot needs to be prepared for
as "the" source of an in-pattern prematurely terminated tow. Except for
training flights, I've never had an in-pattern premature tow termination...but
I know of lots of others who "for real" have, with causes including (off the
top of my head) unlatched canopies, passenger idiocy, improperly connected tow
rings and almost certainly more I'm forgetting.

Stuff happens. Prepare - mentally, training, muscle memory - accordionly.

Bob W.