As an aircraft structural engineer, my job is to design airframes that transfer loads efficiently from one part of an aircraft, say the wing, to another part of the aircraft, say the fuselage. If I didn't do my job right, the wing could rip off the plane before the wheels left the ground. A basic overview of the way we do things can be found in Stanford University's Introduction to Aircraft Structural Design.
Fortunately I have some help in the way of Stress Analysts. These engineers study how the loads are distributed among the structural members, and they make recommendations on the size or thickness of parts in order for them to avoid cracking or breaking altogether. Help = Good. Unfortunately if you put too much thickness (weight) into the aircraft, it has a hard time getting off the ground or meeting performance requirements. Also unfortunate, these Analysts are not incentivized to make an aircraft component as lightweight as possible, because if they screw up on the thin side, the airplane has problems and starts falling apart. You can imagine that this creates somewhat of a conflict between Stress Analysts and the rest of the company. You can also imagine that Stress Analysts tend to err on the side of caution. And oftentimes they add unnecessary weight to the aircraft.
Bruce Ellington asks in his paper "Probability-Based Load Criteria for Structural Design" through examples such as the Hartford Civic Arena collapsing under the weight of a huge snowstorm, "How safe is safe enough?" And if we can quantify it, can we remove the human element which by it's very nature causes buildings and airplanes to be more expensive than they need to be. On the other end, this human element can cause engineers to be "overconfident, or their ignorance catches up" and failures happen. Too often these failures occur when the engineer is far removed or has even passed away, ie our feedback loop is waaay to long. What if there was a way to run a monte carlo simulation on the entire structure's lifecyle before the building's foundation is even poured? We could test the probablility of failure and assess the engineer's design before anything catastrophic happens.
Fortunately I have some help in the way of Stress Analysts. These engineers study how the loads are distributed among the structural members, and they make recommendations on the size or thickness of parts in order for them to avoid cracking or breaking altogether. Help = Good. Unfortunately if you put too much thickness (weight) into the aircraft, it has a hard time getting off the ground or meeting performance requirements. Also unfortunate, these Analysts are not incentivized to make an aircraft component as lightweight as possible, because if they screw up on the thin side, the airplane has problems and starts falling apart. You can imagine that this creates somewhat of a conflict between Stress Analysts and the rest of the company. You can also imagine that Stress Analysts tend to err on the side of caution. And oftentimes they add unnecessary weight to the aircraft.
Bruce Ellington asks in his paper "Probability-Based Load Criteria for Structural Design" through examples such as the Hartford Civic Arena collapsing under the weight of a huge snowstorm, "How safe is safe enough?" And if we can quantify it, can we remove the human element which by it's very nature causes buildings and airplanes to be more expensive than they need to be. On the other end, this human element can cause engineers to be "overconfident, or their ignorance catches up" and failures happen. Too often these failures occur when the engineer is far removed or has even passed away, ie our feedback loop is waaay to long. What if there was a way to run a monte carlo simulation on the entire structure's lifecyle before the building's foundation is even poured? We could test the probablility of failure and assess the engineer's design before anything catastrophic happens.
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