"Jim Vincent" wrote in message
...
Jim, if you go that route, build the strain gauge to display the hook
tension to the pilot for the purposes of flying a winch launch.


Good thought Bill, but I think it require at least two strain gauges to
implement this. Since the direction of the load changes during the course
of
the winch launch, the load could not be measured by just one strain gauge.
Two
are needed to provide the raw data to the instrument. Then, you need to
do a
complete calibration of the system to determine the load ratios for
various
angles and tensions since these are not readily calculatable. Then you
need to
program a CPU accordingly.

Just a simple load / no load determination is far easier.

IMHO, regarding tension values during a winch launch, I've driven hundreds
of
winch launches and believe the only value of a tension meter is to tell
you if
you're approaching the breaking force of the cable/rope. The feedback
from
engine noise, spool speed, glider pitch attitude, etc are far more
valuable to
me when winching.

Jim Vincent
CFIG
N483SZ
illspam

I was thinking that the winch driver would see the glider airspeed via
telemetry and thus control it precisely and the pilot would control the
tension with a panel mounted meter. That way the pilot gets the right
airspeed and precisely loads the glider and cable to whatever value he feels
comfortable with up to the breaking strength of the weak link.

Bill Daniels