Wax rockets
Brian Cantwell was my Ph.D. thesis advisor (I completed my Ph.D. in 1984). The wax rocket was an innovation from one of Brian's more recent Ph.D. students. Much of the work for the wax fueled hybrid rockets was done at NASA Ames. Getting funding for this work has been a nightmare due to NASA Glen being the place where advanced propulsion work is supposed to be done (turf battles are an issue at NASA). The wax rocket is an exciting idea.
Gary