"He is critical, but they are really optimistic," Cox's daughter Amy Cox said. "None of his organs were damaged. Right now they worry about his fractures. Both legs were broken and he's got some facial fractures too."
On Sunday afternoon, Cox's small engine plane crashed into pieces in a wooded area in Moore County.
Other pilots reported that seconds before the crash, Cox radioed that the wings were shaking violently, and the aircraft was out of control. But so far, no one has said for sure yet what happened.
"We don't know, and won't until the FAA or NTSB says this is what happened," air craft mechanic Mike Messeder said.
Messeder says he inspected Cox's plane just over two weeks ago.
"Just normal little stuff with it, I didn't see any kind of problem with it anything like that," he said.
Cox's plane was a 2009 3/4 scale replica of the World War II Fighter P-51. It is a home-built airplane that is considered experimental.
Messeder says Cox had been flying his plane for a little over a year out of a private air strip in Parkton just inside Robeson County Line.
Pilot Vic Carnevale says among other pilots, Cox is known as a "good stick and rudder guy."
"He had a good feel for the aircraft, he was conscientious, never did anything unsafe, always safety conscientious," he said.
Cox's daughter says she never worried about dad's flying.
"He just loves watching how things work, and he has always loved flying even if it's just on the weekends," Amy Cox said. "He always said it was safer up there."
Meanwhile, safety investigators are sifting through the debris for answers as to what caused the crash.