College teams take flight in design competition

  • Published
  • By Keith Quinn
  • Propulsion Directorate
WRIGHT-PATTERSON AIR FORCE BASE, Ohio --  The cornerstones of good competition are challenge, planning, design, and team work. 

After nine months of planning, meetings, board reviews, and e-mails, the Air Force Propulsion Directorate, along with the American Institute of Aeronautics and Astronautics, held the 43rd AIAA Joint Propulsion Conference Student Design Challenge in the shadow of the National Museum of the United States Air Force. 

From June 14-17, 2007, student teams from eight universities competed in design and flight competitions of an integrated propulsion and power system. The unmanned aerial vehicles were assembled from radio controlled kits that were fitted with video surveillance equipment for ground target monitoring and a power consuming device to generate and measure electric power consumption. 

With $7,000 grants from the Air Force Office of Scientific Research, each university team began designing a propulsion and power configuration to be integrated into the test platform. The Design Report Phase consisted of an initial proposal, executive summary, management summary, conceptual design, preliminary design, detail design and test plan. 

The aircraft had size limitations of 80-82 inches wingspan, wing area of 1170 to 1250 square inches, flat bottom airfoil, fuselage length of 62 to 67 inches, and a maximum take-off weight of 15 pounds. This weight included the video camera, data relay, and the 28 volt power consuming device. 

The flight phase began with an unassisted take-off to 250 feet altitude. Each UAV carried an altimeter that relayed altitude to the ground station. After reaching 250 feet, the aircraft entered the flight racetrack. The course consisted of two 180 degree turns 700 feet apart. The aircraft had 10 minutes to complete as many laps as time permitted. Only completed laps were counted while the UAV conducted surveillance and the power consuming task objective. 

"We debated quite a bit over the power aspects of the flight and choice of airframe," said Wright State University student team lead, William Bennett. "We really wanted to push the envelope, so we designed a custom alternator system for the electrical power source. The choice of the Nitro Model Cessna was also daring. We were the only team not to use the Sig Giant Kadet Senior aircraft. Our plane performed well and the addition of a servo controlled camera gave us an accurate and stable surveillance platform with a large field of view." 

After counting laps, the airplanes returned for the final part of the flight phase, the landing. In order to ensure the integrity of the airframe and re-use of the surveillance package, the planes were required to execute a controlled landing. Of the eight aircraft entered, six completed the flight phase. 

The Kansas State aircraft suffered structural damage to the left wing during an engine run-up and withdrew prior to the flight test. There was one in-flight emergency. About 30 seconds into the flight of the Georgia Tech mission, the motor separated from the airframe. The safety training paid off and the pilot was able to dead stick the powerless plane back to the runway in what was best described in the Safety Report as a "controlled crash". The runaway engine landed about a hundred feet away, well within the test area boundaries and it posed no danger to any of the test teams. 

The teams departed Dayton with a job well done but not knowing who won. The winners were announced at the AIAA annual meeting in Cincinnati on July 11. Third place was awarded to California Polytechnic Institute, Pomona. The University of Missouri, Columbia finished second and the winning aircraft belonged to the University of Florida. 

The Wright State University team, led by their faculty advisor, Dr. Scott Thomas, won the Best Design trophy. The other two competing teams were from Northern Arizona University and Western Michigan University. 

"All the teams put in long hours and plenty of hard work. The important thing to stress here is that engineering isn't done with a text book," added John Horner, the Student Design Challenge program manager. "Engineering is a hands-on learning process and it takes education, planning, and team work to successfully solve real-world technical problems. One day these engineers may be developing technology for our warfighters and their Student Challenge experience will pay huge dividends."