Just curious. If a gilder was 100% plastic with a human on board could it be detected by modern radar?
radar can detect raindrops.
As well as conventional airplanes, ships and for some ungodly reason the speed of reasonably driven automobiles in speed zones, but none of these answers the OP.
I assume the OP means “detectable as a plane, and therefore a potential threat, hazard, etc.”
Well yes. Glass and especially Carbon Fiber Reinforced Plastic are not completely invisible to radar, and the long straight edges on the wings help. There’s also metal rods in the wings moving the ailerons and spoilers.
Gliders are less visible than metal planes, though, and civilian radar systems normally only use secondary radar, i.e. transponder signals, which many gliders at least here in Germany don’t have.
I don’t know the answer to the OP, but there are a lot of ‘plastic’ airplanes out there. For example, the Long-EZ, the Quickie, and the Glasair. ISTM there should be plenty of data on RCS on them and other aircraft.
Sounds like it has a good chance of being hidden, but I imagine that it’s one of those things that would really vary based on the glider in question. One specifically made for the purpose would, obviously, be better.
Quite right - but there is a trend toward making these out of composite materials.
It’s going to be quite a while until the last vestige of metal is gone, in things like nuts, bolts and bearings. But given a sufficient budget, it would probably be possible.
The result would be an aircraft that’s hard to detect with normal radars - but given that birds can be radar-tracked, not impossible.