I was reading on the Yahoo news that last week a pilot in England that was flying his private plane (he was alone in the plane) suffered a stroke while flying and was blinded from the stroke.  Thankfully he was not otherwise incapacitated (although you would think being blinded while flying a plane solo would be a tragedy in itself!)  He radioed for help and he was guided to a safe landing by a military pilot who was in the area and heard his distress call and flew close to the airplane and talked him safely down to a safe landing at an airport!

What a totally amazing story that is!  The man is recovering from his stroke, and there was no damage to the plane.