AboutJames Bell Expertise I am a member of Tripoli Rocketry Association, and am certified to fly hi power rockets. I can answer questions anyone may have about design, materials selection, stability calculations, motor selection, altitude and performance predictions, and parachute and recovery options.
Experience I make my rockets from existing kits or parts readily made through commercial channels. I do NOT make my own motor propellants (they are challenging enough even for the companies that do this for a living), and I do not advocate making rockets using "typical household item" such as paper towel rolls.
Question Hi, James my question is that "How does the number of rocket fins compare to the altitude?" and also could you please list some sites pertaining this information. It's for my science fair project.
Thank You A Lot
Answer Bobby -
The main purpose of tail fins is to stabilize the rocket as it flies through the air. The minimum needed to provide stability is three. Four fins is another common configuration. I really can't point you to any sites that discuss this, but there is an excellent book, THE HANDBOOK OF MODEL ROCKETRY, by G. Harry Stine. I find that book to be an excellent source of design information.
You can always add more fins ... I have seen rockets with six and eight fins. But, with each additional fin you are increasing the frontal area for drag, and if each fin isn't perfectly aligned perpendicular to the rocket body, it can increase drag even more and introduce a spin on the rocket. Anything that increases drag will reduce the rocket's overall altitude.
