View Single Post
  #13  
Old June 8th 09, 08:15 PM posted to rec.aviation.soaring
Papa3
external usenet poster
 
Posts: 444
Default Shoulder strap discussion

On Jun 8, 9:36*am, bildan wrote:
A couple of years ago I got hammered in a wave rotor while flying a
G102. *No matter how tight the shoulder straps, my head kept banging
into the canopy. *This is a big enough problem that some glider owners
are re-locating the shoulder strap anchors lower. I think modifying
the seat belt/shoulder harness is a primary structure issue requiring
337 field modification paperwork in most countries. *There's got to be
a better way.

This issue came up again recently which led me to some "out-of-the-
box" thinking which is the reason for this thread.

What if one had inverted "U" shaped, detachable shoulder pad(s) that
snapped or Velcro'd to the shoulder straps or maybe the parachute
harness? *They would come in various sizes to fit different pilots.
In effect, these would raise the pilots shoulders with pads instead of
lowering the strap attachment points. * The pads would press down on
the pilots shoulders as the straps were tightened preventing canopy
head banging. *These pads would be 'personal gear' and not require a
337.

Do these things already exist? *Discussion?


As others have pointed out, there's a whole body of research on pilot/
driver restraint systems. The shoulder straps are clearly intended
to handle longitudinal loads (deceleration), NOT vertical. I can't
lay my hands on it right now, but somewhere or another I found
research indicating the risk of severe spinal damage with excess
downforce provided through the shoulders.

The only right way to accomplish what you want is to focus on the lap
belts or crotch straps. There are dozens of threads on this topic
over the last 10 years. One for example:

http://groups.google.com/group/rec.a...e611e1a0d817a9

FWIW, I have used both 5 and 6 (and, I guess 7) point harnesses in my
gliders for the last 15 years. Since we do extensive ridge running, I
can say that I "wouldn't fly without it" (5 or 6 point harness).

Cheers,
P3