Dynasoar Rocketry HABU rocket glider, 10 flights on E-20PW motors, very fast boost requires perfect boost trim and almost no ability to steer on boost, but the model held up well and flew pretty much dead straight. These are using Aerotech 24mm E-15PW marked motors but that are really E-20PW thrust curve and not E-15 any more. 8.5 pound thrust on a 13.25 oz model.