Science Buddies: "Ask an Expert"

I was wondering if anyone had any ideas of how to easily test the drag on a Hovercraft. This is for a 5th grade science fair project.

Hello and welcome to the forums:

I imagine there are several types of drag on a Hovercraft, at least vertical and horizontal. If you want accurate measurements of drag, I suggest learning about how drag is measured in wind tunnels. Science Buddies site https://www.sciencebuddies.org/science- ... ion1.shtml on building the test section talks about using sensors to measure drag. The article also references NASA's site on wind tunnels: http://www.grc.nasa.gov/WWW/K-12/airplane/shortt.html.

Measuring drag outside of a wind tunnel can be difficult. I did some searching, and there are plenty of articles about hovercraft drag, but little to nothing about measuring it. I think that if you used a fishing scale on a line, and pulled the craft along at a fixed speed, you could measure the drag vs. speed this way.

Best, Keith