How+will+it+work

We used 2 types of Engine, type 1 made our rocket stay in the air for about 1.54 sec, it took off alright, came back alright. None of the parts were damage at all. Parachute was released, no recovery was done to the rocket. The 2Nd time when we launched it was not really controlled at all, instead of going straight it went side ways for at least 4 secs. It did work but was way to heavy for both of the engines, Fins were designed properly. There was no problem structural wise, except we learned that we should had chosen something lighter.