22 to drive an unpowered blast wave 38 out of the nozzle defined by the afterbody 42 and shroud 17 in the manner shown in fig6 as the lasercraft moves through the atmosphere at about 30 km altitude the lasercraft 44 rockets into space per fig7 and the fuel ring 20 continues to ablate delivering thrust per arrows 49 which flow smoothly aft and out the lasercraft nozzle now free from the sensible atmosphere e g per fig6 as shown in fig5 the afterbody 42 of lasercraft 40 is preferably shaped as an off axis parabola while the trailing edge 46 of the shroud 17 angles toward the trailing portion 45 of the parabola 42 on either side fore or aft of the afterbody tip 43 that is cooperating with the afterbody is the shroud or cowl 17 which directs the aft propulsion flow over the afterbody preferred is a shroud with a trailing edge angled toward the tip 43 of the afterbody 42 per fig5 these two components cooperate to retain the lasercraft in its pulsed laser beam such as beam 26 of fig6 thus per fig5 the leading wall 21 of the shroud 17 can be at an angle of 30 u00b1 15 u00b0 with the vertical as shown in fig5 such wall 21 would pivot at crook k which is preferably located at focus u2018 p u2019 of the parabola of fig5 self centering of the lasercraft embodiments of the invention can take place as shown in fig8 and 9 hereof that is when the lasercraft 10 also shown in fig1 amp 4 goes off center of the laser beam 26 per fig8 and 9 the blast wave diverts the exhaust 29 to the right causing the lasercraft 10 to.