I belong to an organization named Science Olympiads. One event is named Bottle Rockets. The object is to shoot a 1L soda bottle into the air and put as much time as you can between launch and touchdown. My question is this, what is the best ratio of length for the nosecone on a rocket? It seems that rockets are alike enough that there would be some ratio like 1m of nosecone to 20m of rocket. Anyone have any ideas about this?