Dr. Tom McConnell, Ball State University professor and science teacher educator, launches some rockets at Washington STEM Academy Monday with the help of students. Photo by David Slone, Times-Union
Dr. Tom McConnell, Ball State University professor and science teacher educator, launches some rockets at Washington STEM Academy Monday with the help of students. Photo by David Slone, Times-Union
As they watched rockets shoot 1,200 feet in the air or more, Washington STEM Academy fifth-graders didn’t take their eyes off them Monday.
The rocket launch was provided by Dr. Tom McConnell, Ball State University professor and science teacher educator.
According to Washington teacher David Burden, the fifth-graders are learning about the scientific process using straw rockets. Bringing in experts like McConnell will help the students as they design their own rockets. Burden met McConnell over the summer during Warsaw Community Schools’ Math Science Project, which helps teachers do some inquiry-based projects in their classrooms.
McConnell said all his model rockets are homemade designs, with some from kits. Four of them were his custom design. While some use low-power engines, others use mid- to high-range engines.
The largest rocket he brought with him, which stood about 6 feet, can only be used by someone who is certified by the National Association of Rocketry. He did not shoot that one off because of lack of space and because he would have to get Federal Aviation Administration approval.
He shot off three rockets for the students. The first one broke into two pieces, the second landed in a tree and the third came down in two pieces.
“Hopefully, the kids will take what we talk about today and help design their own rockets,” McConnell said.
Before going out to the athletic field to shoot the rockets, he spoke to the students about the science of rockets. “As we talk about this, think about what you want on your rockets,” he told them.
There are three forces that work on rockets when they fly: lift, drag and thrust, he said, explaining each force.
He explained the different engines. Every letter – from A to B and so on – has twice the power of the previous one.
He also went into the shapes and designs of rockets and their fins, which help the rocket fly straight. There are many different shapes the rocket and fins can be.
The center of gravity and center of pressure are two very important aspects of rocket building. He said the ideal design of a rocket means the center of gravity is in front of the center of pressure. The center of pressure should be at the top of the fins or further back, he said.
“The main factor when I design rockets is the distance between the center of gravity and the center of pressure,” he said.
The center of pressure can be changed by adding fins, having bigger fins or changing the fin shape and position. Rockets can have three, four or six fins.
McConnell then explained four ways students could calculate the center of pressure, suggesting the swing test would be easiest. If a rocket is balanced, it will fly nose-first as the student twirls the rocket around them. If it isn’t balanced, he said the rocket would fly all around.
“How the rocket behaves is an indicator of stability,” he explained.
When firing a rocket, it should have four phases: thrust, glide, ejection and recovery.
After the in-class discussion, the fifth-grade classes went outside for the rocket demonstration. Student volunteers helped McConnell prepare and fire the rockets.