On Monday, June 1, 2015 at 8:45:14 AM UTC-7, Papa3 wrote:
On Monday, June 1, 2015 at 11:26:28 AM UTC-4, Dan Marotta wrote:
Perhaps a pulley mounted to a 2 x 12 of sufficient length that the
glider sits on the board to hold it down.** Position the glider on
the board to get the desired angle and put a couple of people in the
cockpit.* Use a spring scale and come along to set the desired
tension.



snip


We're thinking along those lines too. However, to check a CG hook at the rope angles normally experienced, the pull angle has to be something line 45 degrees down from horizontal. That's going to be complicated.





--

Dan Marotta

Yup. Was involved in a similar exercise many years ago when John Campbell was investigating critical angles on Schweitzer releases. If the glider is assembled, you can get a group of folks together and lift it onto some tall saw horses supporting the wings near the root. Use big pads to avoid crushing the skin. Even better would be to take the wings off and support using the lift pin hardpoints. If you do this over a solid tie down (airport tiedown ring), you'll only need a small pulley and you can move the fuselage forward or backwards to get the required angles.

A variation of Dan's idea is pretty simple. Take a 12 ft. or so plank with one end under the main wheel and an eyebolt at the desired point under the CG hook. Let the free end of the plank extend beyond the nose of the glider and link the hook to the eyebolt so that the plank is held up at the nose end. That allows someone to sit on the tail and another person to put tension on the rope by pushing down on free end of the plank.