PROJECT AQUILA 211 ENGINEERING DRIVE AUBURN, AL POST LAUNCH ASSESSMENT REVIEW

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1 PROJECT AQUILA 211 ENGINEERING DRIVE AUBURN, AL POST LAUNCH ASSESSMENT REVIEW APRIL 29, 2016

2 Motor Specifications The team originally planned to use an Aerotech L-1520T motor and attempted four full scale launches with this motor. Unfortunately of these four launches, two launches were catostropic at take-off due to faulty motors. Aerotech has taken responsibility for both of these motor CATOs. After the second CATO, the team decided to switch to a Loki L-1482 for the final full scale launch. Payload Overview The team chose two payloads, a fairing payload and grid fins to serve as an aerodynamic analysis payload. PLF: Traditionally, a payload fairing (PLF) is used to protect a scientific payload during the launch process. However, for Project Aquila, the PLF was used house the drogue parachute and one of the main parachutes. Prior to deployment, the PLF acted as the aerodynamic nose cone. A lowdrag elliptical design was chosen do to the low-altitude, low speed nature of the competition. Grid Fins: The overall objective for the aerodynamic analysis payload is to obtain accurate aerodynamic data for an aerodynamic protuberance. The chosen protuberance was a lattice/grid fin. An in depth analysis of the grid fin was conducting using computational fluid dynamics (CFD) and a series of simulations and models designed to determine the grid fins interaction with the flow field. Using this data the team was able to complete the secondary objective for the aerodynamic payload. The gird fins served as air brakes for the rocket upon ascent to ensure the rocket would meet the 5,280 ft altitude mission requirement. An Arduino was used to command the servos that actuated the grid fins. The Arduino received input from a 10 DOF data acquisition system to determine when to deploy the grid fins.

3 Vehicle Dimensions The vehicle body was comprised of a 5 in inner diameter isogrid tube. The total length of the vehicle was inches, including a in fairing system, a 25 in upper section, and a 37 in booster section including the grid fins payload. Altitude Reached (Feet) Due to failures in full scale testing, the team was unable to launch in Huntsville and therefore no altitude was recorded. Vehicle Summary The vehicle utilized carbon fiber braiding for the body tubes that were formed into an isogrid type structure using a fiber glass skin. The vehicle weighed a total of 31.3 pounds. The relatively high weight is due to errors in simulating the rocket early on in the design process, additional weight was required to avoid surpassing an apogee of 5600 feet. Data Analysis & Results of Vehicle Due to failures, the team has no recorded data of the flights. No accurate analysis or results can be concluded from the flights. The team has experienced five test flight failures. The first failure was due to faulty simulations causing the vehicle to be underweight. The second was a motor failure which resulted in the total destruction of the vehicle. The third was due to the payload fairing deploying prematurely, which caused a recovery failure and total destruction of the vehicle. The fourth was a motor failure, which resulted in the total destruction of the vehicle. The fifth and final failure was an epoxy failure which caused a fin to detach at transonic speeds, this ultimately led to a ballistic approach to the ground and the total destruction of the vehicle. Payload Summary The payload fairing was designed to house both the drogue and main parachutes. The two halves were to be separated using a black powder charge, allowing the deployment of the

4 parachutes. The payload was constructed using ABS from a 3D printer and was reinforced with fiberglass. The grid fin payload was designed to cause drag by extending outward from the vehicle in order to reach the altitude goal. The fins were attached to individual servo motors and were printed from HIPS using a 3D printer. The goal was to determine the aerodynamic characteristics of the grid fins and how they could manipulate a vehicles flight. Data Analysis & Results of Payload Due to the series of failures in full scale flights, there are very few flight results for the payloads. On the fifth full scale launch the grid fins did actuate (confirmed visually from footage of the launch) but as the launch was catastrophic before apogee and the rocket was irreversibly damage upon impact, no data was collected. The payload was catastrophically damaged in all failed launches. Scientific Value The use of the isogrid structure as an airframe in rocketry was a novel approach to improving the strength to weight ratio of body structures. The structure was proven to be successful and will be implemented in future rockets as a strong, lightweight airframe. Additionally, the team was able to collect data on grid fins as drag surfaces and plans to continue to improve on this design for future applications. Visual Data Observed On the flights which the motor did not fail, the vehicle flew very stable and had every indication of being aerodynamically sound. The grid fin payload deployed visually, however the effect they had on the rocket is unknown at this point. Lessons Learned The Auburn team learned a lot about manufacturing and production due to the four full scale rocket rebuilds required due to failures. Unfortunately the rebuilds consumed a massive

5 amount of time and as a result, our documentation suffered. This was a building year for our team and we were successful in recruiting many new members, particularly underclassmen. This means a large portion of our team members will be returning next year and are inspired and dedicated to making next year a success. Summary of Overall Experience Despite the series of failure experienced by the Auburn team this year we were able to make great strides in our program development, successfully designing, building, and testing many new technologies that can be implemented in future builds. Perhaps our greatest innovation leap was the use of the carbon weave isogrid body tube, a material we look forward to using in future designs. We are incredibly proud of the Team Spirit Award we won at the competition in Huntsville and cannot wait to show off a successful Auburn rocket next year. Educational Engagement Summary The Auburn team completed a series of Educational Engagement events reaching over 2,000 middle and high school students. The biggest education event completed by the team this year was Rocket Week at Drake Middle School where the team successfully built and launched Alpha rockets with over 6007 th graders. Budget Summary While the team managed to keep the price of the rocket on the pad well under $7,500 at $4,014, the team s overall spending was hugely impacted by the four full scale rebuilds and motors.