Sketch created by 1989 National Boating Safety Advisory Committee Subcommittee on Propeller Guards to illustrate the portion of a boat in the water when it is on plane vs. at rest or off plane.
Houseboat Propeller Regulation Proposed and Withdrawn by USCG: Analysis by PGIC
History of Boat Propeller Safety
Mitigating Boat Propeller Injuries & Fatalities Chart
Four Volume Review of the Boating Industry’s Boat Propeller Guard Product Liability Defense