When designing airplanes, engineers pay attention to details, such as the position of two important points: the center of gravity and the center of pressure (also called the center of lift). On an airplane, if the center of gravity and center of pressure points are reversed, the aircraft’s flight is unstable and it will somersault into chaos. The same is true for rockets and missiles!
Let’s find the center of gravity on your airplane. Grab your flying machine and sharpened pencil. You can find the ‘center of gravity’ by balancing your airplane on the tip of a pencil. Label this point “CG” for Center of Gravity.
Materials:
We're going to make a paper airplane first, and then do a couple of wind tunnel tests on it.
For the project, all you need is a sheet of paper and five minutes... this is one my favorite fliers that we make with our students!
Find the Center of Pressure (CP) by doing the opposite: Using a blow-dryer set to low-heat so you don’t scorch your airplane, blast a jet of air up toward the ceiling. Put your airplane in the air jet and, using a pencil tip on the top side of your plane, find the point at which the airplane balances while in the airstream. Label this point “CP” for Center of Pressure. (Which one is closest to the nose?)
Besides paying attention to the CG and CP points, aeronautical engineers need to figure out the static and dynamic stability of an airplane, which is a complicated way of determining whether it will fly straight or oscillate out of control during flight. Think of a real airplane and pretend you’ve got one balanced on your finger. Where does it balance? Airplanes typically balance around the wings (the CG point). Ever wonder why the engines are at the front of small airplanes? The engine is the heaviest part of the plane, and engineers use this weight for balance, because the tail (elevator) is actually an upside-down wing that pushes the tail section down during flight.
Let’s find the center of gravity on your airplane. Grab your flying machine and sharpened pencil. You can find the ‘center of gravity’ by balancing your airplane on the tip of a pencil. Label this point “CG” for Center of Gravity.
Materials:
- sheet of paper
- hair dryer
- pencil with a sharp tip
We're going to make a paper airplane first, and then do a couple of wind tunnel tests on it.
For the project, all you need is a sheet of paper and five minutes... this is one my favorite fliers that we make with our students!
Find the Center of Pressure (CP) by doing the opposite: Using a blow-dryer set to low-heat so you don’t scorch your airplane, blast a jet of air up toward the ceiling. Put your airplane in the air jet and, using a pencil tip on the top side of your plane, find the point at which the airplane balances while in the airstream. Label this point “CP” for Center of Pressure. (Which one is closest to the nose?)
Besides paying attention to the CG and CP points, aeronautical engineers need to figure out the static and dynamic stability of an airplane, which is a complicated way of determining whether it will fly straight or oscillate out of control during flight. Think of a real airplane and pretend you’ve got one balanced on your finger. Where does it balance? Airplanes typically balance around the wings (the CG point). Ever wonder why the engines are at the front of small airplanes? The engine is the heaviest part of the plane, and engineers use this weight for balance, because the tail (elevator) is actually an upside-down wing that pushes the tail section down during flight.
Yes, it’s something I have been working on for a couple of months, and I’ve recently been gathering up all the feedback from folks like you so I can make it the way you’d like it to be!
If you do have suggestions before I finish up the work on it, feel free to email me directly at [email protected] and let me know what you like (what we should keep) and what could be better (and how?)… that makes it so much easier than trying to guess at what I think will work for you!
One of the biggest challenges has been the sheer amount of content on the site, and organizing it in a way that you can find it without getting all mixed-up. I am also making it able to track your progress, so you can tell how much of each section you’ve completed in addition to being able to be led step-by-step through each different science area. Currently when you cross over to the Grade Level section, the navigation still thinks you are in the Topics section and mixes up the menus on the right, so you have to go back to the Grade Level Topic in order to stay in sequence. Originally I thought I could just fix this easily, but it’s requiring a LOT more work than I initially thought!
These major updates should be complete within the next couple of months. Note that I am not going to change it all right away – these new changes will first appear a separate (but otherwise identical) site for you to test out and try it out and provide me with more feedback, and then I will move it over to take the place of the current navigation. I’ll let you know when you can test it out for me. Thanks!
I saw something that said you were going to update the navigation? What’s that going to be like? ANd when??
Does it work now?
the vidio wont’ load up!
I love this plane.
We really enjoyed this flying paper Machine and finding the center of pressure.
instead of using a blow dryer, I used a small personal fan. I found the center of pressure by putting my pen in different places inside the V of the wings. when it spins around, that is the center of pressure!