(under subclass 102.1) Subject matter wherein (a) a long, slender element (e.g., boom, spar) is detailed which is connectable (1) at one of its ends to a mast, and (2) at its opposite end supports one corner of a triangular extent of material for propelling the marine vehicle through the water, (b) the extent of material having (1) an apex, (2) a base, (3) two equal length sides and (4) supported only at its corners and apex (i.e., spinnaker).
