I decided t' make a Johnny Rockets paper ketchup bowl into a model flyin' saucer. It is 4.5" diameter and weighs only 0.4 oz empty. Blimey! I test flew it on an Estes B6-4 for its first flight. it was perfectly stable and flew straight up with no wobble. On descent it fell straight down with no tumble. Blimey! OK, ya bilge rat, let's try a motor that has 8 times t' thrust!. An old (discontinued - too bad!) Aerotech E25-11 fit t' bill and here be t' video. This time it whipped off t' pad and flew straight up. On descent it tumbled because o' t' heavier motor.