On Thursday, December 31, 2015 at 1:13:22 PM UTC-5, Tim Taylor wrote:
Just thinking outside the box. Why not put an all internal back-up camera system in the plane?

Likely because you're looking at something ~200' away, makes it hard to see from a camera/system designed for ~12' away.
Hmmm..... since you're tapping into the airplane electrical, wonder if that trips a "more paperwork" issue.....