I saw an interesting artifact while in the North Atlantic. With the range
set to 30 miles, we had a huge reflection at 25 miles... would have been
several miles long.
We were several hundred miles offshore, perfect visibility and there was
definately nothing there.

The puzzle was solved when we realised the artifact was on the same bearing
as Bermuda, 350 miles away. The antennae was catching Bermuda's reflection
of the previous pulse (which was interpreted as reflection of the current
pulse from an object 25 miles away). The difference in distance (times 2)
divided by the speed of light equaled the pulse frequency of the radar unit.
Isn't physics great when it works?

The artifact lasted about 20 minutes. We were in the area for another month
but never saw the effect again. I assume it had something to do with
atmospherics skipping the signal.

Anyone ever seen this?

Bruce