Originally Posted by

**blueridge** Read my reply through yours:

Any hint given about what is supposed to be limiting the distance he can see?[No, hints leading to the right answer].

If nothing else is in the way, I would guess that it's determined by the curvature of the earth. Does that help?[What do you mean by curvature of the earth]?

Try drawing a diagram of the situation and figure out what is the furthest point he can see. [I calculated it based on this and I got a distance of 229 miles at 35,000 feet]

Can you further explain your reasoning?

Can you provide steps?