SLFplatine
Early in this blog, I made a post concerning radar tracking by naval vessels that may have been close to the flight path of the aircraft. I did not receive a reply from anyone at the time and maybe you could answer the question: would naval vessels be able to track the aircraft using primary returns and, if so, what would be the range if the aircraft remained at a FL greater than FL200?
I was assuming that there would have been some naval vessels, from various countries, operating somewhere in the area believed to have been overflown by the aircraft.
Regardless I would think it would be safe to assume the U.S. has satellite coverage of everything that moves in that neighborhood.
Typical naval air search radar operates out to approx 450km and to a height in excess of 150,000ft.
There may well have been many warships out there but the radar operators are trained to take notice of a contact if it threatens the ship, ie... Flies towards it. Single contacts at high altitude on a constant heading are usually deemed friendly and ignored.