Re: Gen Nav
A small circle is defined as any circle on the surface of a sphere that is not a great circle. However HWD's definition is also correct, and since a sphere can always be chosen that can be drawn through a given 4 points then the answer is 4 points - with the exception that if they are all on a great circle then it cannot be done (as the great circle is, by definition, not a small circle!).
Send Clowns
Former Gen Nav instructor, BCFT