A very successful adaptation of my "Pocket Jet 2" geometry into a triple pipe pulse jet. Volumes were triple and all lengths were the same as its single parent, but thrust was sqrt3 of instead of the 3x expected. Faaaaascinating... I've been meaning to make a double and see if the thrust is sqrt2 instead of 2x. Big case for having separate ducts instead of melding them into a single combustor. This one split open at a UK meet that I put together.