Science Buddies: "Ask an Expert"

Hello again, I'm facing another problem conducting the experiment named "How Far Will It Fly?" Actually, it's more of an uncertainty issue. I folded the paper airplane following the exact instructions and it came out fine, it flies great. However, when I modify it to add drag and throw it, it refuses to fly! After several attempts at making new planes and trying different ways to throw it, I'm still experiencing the same results. Am I on the right track or am I doing something wrong? Once again, thank you so much for the help!

samiha - Try reducing the amount of drag you are inducing by making the tabs smaller or reducing the angle of 'bend' on the tab. You don't want to add so much drag as to prevent the airplane from flying, just an amount that will change the flight characteristics such that it can be reliably measured.

Rick Marz

Thanks once again for your help Rick! I have tried making the tabs of various smaller sizes and fold them to a 90 degree angle. For example, with one inch tabs, the plane in still incapable of flying straight and makes an array of dips and turns before hitting the ground. Is that still considered as a valid flight?

samiha - I think that 1" tabs at 90 degrees is way too much drag. The fact that it refuses to fly probably isn't the gradient of drag the experiment anticipated. I think you should try to attain some reduced performance flight for your experiment. Remember the forces in effect in 'straight and level' un-accelerated flight are Thrust=Drag, and Lift=Gravity. In your experiment, thrust decreases instantly and you have significant drag. Therefore, gravity takes over quickly and the plane quickly lands (crashes). I'd make the tabs less than 0.5" and bend them less than 90 degrees.

Rick Marz

samiha - I think that 1" tabs at 90 degrees is way too much drag. The fact that it refuses to fly probably isn't the gradient of drag the experiment anticipated. I think you should try to attain some reduced performance flight for your experiment. Remember the forces in effect in 'straight and level' un-accelerated flight are Thrust=Drag, and Lift=Gravity. In your experiment, thrust decreases instantly and you have significant drag. Therefore, gravity takes over quickly and the plane quickly lands (crashes). I'd make the tabs less than 0.5" and bend them less than 90 degrees.

Rick Marz