In a previous post, I discussed how our integrated curriculum in the Academy of Aerospace and Engineering uses a spiral approach to learning. This means we revisit concepts in different classes and over time so that students repeatedly get a chance to solidify their learning. One recent example of this approach is in how the students are learning about aircraft propulsion.
In science and aerospace science, the 7th graders first learned about the forces of flight, including thrust, the force of propulsion. They also studied Newton’s Laws and learned that the Third Law explains how thrust works for both propellers and jet engines. Then they studied types of engines, including reciprocating (piston) engines and jet turbine engines. Finally, Ms. Garavel tasked them to do an engineering design project to redesign the propeller on a Guillow Strato Streak rubber band powered airplane. Each student crew (group of 4 students) is designing and 3D printing their propellers and will test them on the Guillow model airplane this week. In two weeks, the academy is going on a field trip to Pratt & Whitney and to the New England Air Museum to learn firsthand about jet engines and propulsion systems. Therefore, the 7th grade students have had repeated lessons where they learned about Newton’s Laws of motion, the forces of flight, and propulsion systems. Here is a photo of our two 3D printers with two different crews’ propeller designs on the build plates and a Guillow Strato Streak between them to show the original propeller that they are redesigning:
The 8th graders have spiraled back to learn more about aircraft propulsion systems in a two significant activities. First, I assigned a project where each 8th grade crew plays the role of an engineering team in an airline company in which the CEO has tasked them to re-engine the fleet with new Pratt & Whitney Pure Power geared turbofan engines, then to re-imagine a use for the old jet engines. For the first task, the students had to research and learn about the new Pure Power engines, then select the right model for each airliner and present their plan back to the CEO (played by Mr. Dias, our Principal). For the second task, the students used the engineering design process to research and brainstorm a new use for the old jet engines. The students will present their idea in the form of a business plan back to the CEO again this Tuesday. The 8th graders are also doing a more hands on project, as I assigned them the Electric Cargo Airplane Challenge developed for high school students by the American Institute of Aeronautics and Astronautics (AIAA). This is a tough challenge where students design and build a model airplane powered by one or two (their choice) 6-volt electric motors with propellers. The students must build the airplane from scratch, though they may use stock propellers and wheels. The electric motors are also provided to them. The electricity is supplied by a wire to the airplane that is connected to a heavy pole around which the airplane flies. The thrust is the same for every crew, since they all use the same power source, so the real challenge is to minimize weight and drag to effectively increase the net force (thrust) available.
I tried this project for the first time last year, and none of the six crews were able to really get their airplanes to fly, except for one crew that kept working on the airplane and finally got it flying after the project was officially finished. I shared this experience with my students this year, and they listened and improved on last year’s performance — so far, all three crews that have done the project have successfully flown their airplanes after some redesigning. The other three crews will start building their airplanes this week. We will have a fly off of all six crews in about three weeks. Here are photos of the first three crews with their airplanes, and some screen shots of a video of the first successful airplane to fly (the airplane of Crew 4, the second crew shown here):
When we did the flight tests of these three aircraft this past week, we had some college engineering students from UCONN’s chapter of AIAA visiting us. They presented to the students about UCONN’s engineering program, and they observed and mentored the academy students. After they watched this flight test, and saw the 7th graders busily working on their 3D printed propeller project, one of the AIAA students told us, “I can’t believe how much these students know and what they are capable of doing here.” He was surprised that middle schoolers knew anything about aerodynamics or propulsion or that they could do engineering projects. The reason this is possible is because of our integrated curriculum and spiral approach to learning.