Dan G wrote:
BTW a correctly fitted four-point harness is as safe as a five-point,
although I do recall that the six is the best. As long as you *fully*
tighten the lap strap *first* on a four-point, there should not be any
issues with submarining. I seem to remember that if you do submarine
with a five point, you're going to be left with serious groin injuries
(that's why a six is best), so correct fitting is more important than
variant.

My recollection is "correct fitting" may not be good enough with "older"
gliders that have a shallow seat pan, compared to "newer" gliders, where
the seat pan has a substantially angled pan below the thighs. Really
"old" gliders with upright seating might also be OK.

I have talked to ridge runners that tell me it doesn't matter how tight
you make the lap belt on a 4 point harness, it simply doesn't work as
well as a 5 or 6 point harness while you are pounding along low and fast
on the ridge. That might be a different issue than proper restraint in a
crash.

--
Eric Greenwell - Washington State, USA
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