I put my Davis up on the backstay at about 15ft. That and the mast/boat body give a solid reflective signal for radar monitors to see. Being up there means I do not cut myself. It is not contacted by the sail. Only issue is in a strong breeze it will react and will move the backstay. So I get a vibration in the boat. Kind of an early warning that the wind is up and you may want to tie down stuff.
Same here. With the, uh, "early warning signal" feature one might want to make sure the anchor is still holding good.
With the reflector mounted on our backstay just above where the lower split backstay (due to the walk-through transom) where it meets the single cable/stay, I mounted it so that the "rain catch position" is vertical. This required drilling a couple holes for each U-bolt. Note that the "rain catch" position doesn't work perfectly for every horizontal angle while under sail because of the boat's heel angle.
My radar is getting along in years, but way back when, another factor to consider is that wet surfaces, and it could be sail cloth (although I don't know this for a fact), reduces the echo return so if the reflector is one one side of the sail from where the other boat's radar is then it won't show up as well. Perhaps high-powered radars like those on ships could penetrate wet sails better? For our trips further north I have thought about adding one of the Plastimo radar tube reflectors to each stay (one port and one starboard) in addition to the Davis backstay one but haven't done it (still thinking about it).
Because of the split backstay, the upper part of the backstay doesn't rotate if just above the split so that's a plus. If it could rotate, as perhaps with a single backstay cable, then the rain catch position wouldn't be assured.
Backstory: I've had two very close encounters with "targets" that didn't show up very well. One being a huge wood barge on a mooring buoy just south of the Tacoma Narrows bridge and this was on a very drizzly and foggy day. Almost T-boned that sucker. The other was at night, drizzly conditions but no fog, up the inside passage, miles from anywhere, where we were almost T-boned by some large wood trawler running with his lights off (again, wet and wood). I'm told they often do this for better visibility.
