By the time the finished vehicle sits on the launch pad for its first flight, it will already have crashed and burned more than a hundred times. Before we install a single bolt, the entire Structures & Aerodynamics team have already spent hours thinking about how that particular component might lead to a catastrophic failure. Will the bolt be able to handle the thrust and drag loads placed on the vehicle during launch? How about the loads during stage separation? Will the bolt head cause a supersonic shock that rips apart the vehicle? Could the metal in the bolt form a thermal short that carries heat from the supersonic atmosphere past the thermal protection system and into the vulnerable composite airframe?

In engineering, we call each of these catastrophic scenarios a “failure mode,” and a surprisingly large part of designing a successful mission lies in discovering all of these failure modes ahead of time and ensuring that they do not occur. Given enough time and resources, a team of engineers can design around almost any problem, but first we need to know what problems to design around in the first place.