A boost technique which uses 2 or more motors side by side in t' same rocket. Avast, me proud beauty! Blimey! Safe operation o' rockets with different motor thrusts, me bucko, in a cluster would be t' ensure symetrical thrust around t' center vertical axis o' t' rocket. This is also sometimes accomplished by cantin' motors toward t' center o' gravity. Well, blow me down! Blimey! See also Vectored Thrust.