Hunter 58,
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.