What are the various insurance requirements for an owner of a general aviation aircraft?
The basic rule is that insurance is required in general aviation, and proof of that insurance has to be carried in the plane. In addition to having proof, one must have the correct amount of insurance for the planned flight or equipment. This is determined based on the aircraft’s categorization (e.g. – maximum takeoff weight [MTOW]).
Source: What are the various insurance requirements for an owner of a general aviation aircraft?