On Sep 11, 9:49*pm, Canav8 wrote:
One of the best materials I have ever seen is Aluminum (Speed Tape) on
a leading edge. It has a very high reflective capability and if laid
out smooth would have minimal impact of airflow. Just a thought. It
flashes every time you see them in a turn. *D

I experimented with a similar idea. I first encountered this idea
when visiting a soaring RC soaring club event and seeing something
shiny on the leading edge of many ships. It was explained to me that
if the pilot on the ground looses contact with his glider, he puts it
into a circle and can detect the flash. I asked about a source and
was directed to fishing supply houses for "prism" foil tape such as
used on many fishing lures.

The concept is similar to the aluminum speed tape mentioned above
except that prism tape comes in many colors, patterns and may be more
reflective ... or at least more colorful! See
http://www.barlowstackle.com/Fishing...Tape-C133.aspx for many
examples.

I had some conversations with Dick Johnson about this concept and he
became interested. Unfortunately, his untimely death prevented any
more research.
We agreed that there were some items that need more experimentation;

1) Leading edge tape seems the best location but will that trip the
boundary layer? My experience is that the fishing tape is "very thin"
but I am unsure if it is as thin as aluminum speed tape. This can be
a major road block for acceptance by competitive pilots, who are the
most likely to be flying in close quarters. Dick would have been a
great person to perform this type of experiment.
2) How easily can it be removed? Speed tape is basically intended to
be non-permanent (to be replaced by a permanent repair) but fishing
prism tape is probably not. Note that during my testing I used wing
tape to temporarily secure the prism tape.
3) What reflective surface is "best", at what distances (1000ft? 1
mile?) and which lighting situations (sun, clouds)? Solid silver
speed tape? Prism fish tape (which color)? That would be pretty easy
to test on the ground by holding equally sized examples.
4) How well do they weather? I might guess that speed tape's shine
looses it's luster over time. Maybe fishing lure prism tape would not
fade due to the environment it is used in.
5) Could the reflective coating be integrated into the gel coat during
manufacture?

We have had far too many accidents this year and some might have been
avoided if the gliders had seen each other earlier. Powered airplanes
have anti-collision lights and beacons, we do not. Powered airplanes
have lots of different paint schemes, we typically do not. Powered
airplanes have larger/taller profiles, we have thin ones. Powered
airplanes don't fly in gaggles, we do.

The bottom line is that a reflective surface is better than dead white
or even a painted surface (no matter the color).

Thanks, my $0.02, John