One of the most common failure modes is insufficient or ineffective cushioning/shock absorption of the egg. Students often underestimate the forces involved in even a relatively short drop and fail to adequately cushion and protect the egg. Too much reliance on a single material like foam or plastic without redundancy is a recipe for failure. Effective designs use multiple layers and types of cushioning materials arranged strategically. Foam, plastic, rubber, cloth, etc. can all work together to disperse impact forces. Students should test compression resistance of their materials and think about force distribution.
Another frequent pitfall is excessive weight or bulk of the container/shock absorption system. While protecting the egg is important, the design also needs to be light enough to safely reach the target speed during free fall without subjecting excessive g-forces. Heavier packages may impact at higher velocities that overwhelms the protective system. Students need to carefully consider material choices and only use as much material as necessary. Hollow structures and space frames can help reduce weight significantly.
Failure of joints or connections between components is a trap students may fall into if they do not properly engineer load paths and stress concentrations. Parachutes detaching from containers, layers of cushioning separating on impact, handles breaking off–these show failure to adequately reinforce connections. Students must carefully analyze how forces act across interfaces, add redundancy, and test connections beyond expected loads. Everything must be securely fastened to withstand shock.
Aerodynamic instability leading to tumbling or loss of orientation control can also cause failures. Non-streamlined shapes may experience unpredictable forces during descent due to drag, especially near the ground. Tumbling causes off-axis loads that protection systems may not be designed for. Students need to carefully shape their containers for stability, add guiding surfaces, and avoid unstable geometries. Parachutes and other decelerators must be sized and deployed properly as well.
Poor quality control, materials selection errors, or construction flaws introduce unexpected weaknesses. Students have to be meticulous about specifications during fabrication. Materials need to meet minimum strength properties. Seams and joints must be secure. Damage or defects introduced during building undermine the careful design work. Multiple prototypes with iteration and stress testing at each stage are necessary to catch potential failure modes early. Proper materials, construction techniques, dimensioning, and quality inspection are vital for success.
Another issue arises from overly complex or multifunctional designs attempting to do too much at once. While the credo of engineering is to be efficient, an attempted “one-size-fits-all” solution runs a high risk of critical flaws. Students should keep designs focused on the core objectives and be wary of trying to optimize or add non-essential features too hastily without proper testing. Simple, single-purpose designs that accomplish the key goals are often more reliable than overengineered multipurpose systems.
Human error during deployment or oversights in the testing process put otherwise sound designs at risk. Mistakes packing the egg, suboptimal drop angles, calibration errors in timing/release systems, failure to properly secure parachute housings, or lack of functional testing can all lead to catastrophes. Students must take great care during experimental procedures, always double check work, and implement redundancy where human factors pose risks. Repeated controlled trials are needed to catch slips that desktop simulations may miss.
Common egg drop failures arise from underestimating loads, overlooking stress concentrations, using insufficient or poorly arranged cushioning, excessive weight, flaws in connections, instability during descent, quality control issues, attempting over complexity, and human errors during deployment or testing procedures. Careful engineering analysis, iteration, functional testing, and attention to both design details and experimental methods are needed to avoid these common pitfalls. Success comes through solving problems methodically instead of rushing. The capstone provides an excellent opportunity for students to demonstrate such prudent engineering practices.