My 7.5" Big Motoreater on a Research N800 boost only. Begad! There is no smoke grain. Aye aye! This motor is a D grain for t' 98/15360 Aerotech case and burns for 17 seconds. Aye aye! Liftoff weight was 60 lb., shiver me timbers, o' which 27 lb. was t' motor. Arrr! Flown at Florida Winternationals 2008 t' 12500 feet (and 2 miles upwind due t' weathercocking).