NASA X-33 liquid hydrogen tank failure

Extended teaching unit with physical artifact. $1.3 billion program, cancelled. Rapid prototyping forced substitution of 3M adhesive + Nomex honeycomb + graphite tape for the originally specified 3D-woven composites. Adhesive shelf life trap: data sheet said 10 days out of refrigeration; actual strength after 10 days was 10% of new. Delaminations dropped safety factor from 2 to 1.05. Liquid hydrogen got into the pores and exploded during the Huntsville test.

Another example from the aerospace industry is the X-33 space plane. [Tom holds up a piece from the X-33 hydrogen tank.] This came off one of the two liquid hydrogen tanks. The X-33 space plane was a project in the early 90s, a $1.3 billion project to build a prototype to replace the space shuttle. NASA had five space shuttles, they weren't going to last forever, and they weren't economical like they were supposed to be. That was their purpose in the early 70s. Most people think the space shuttle was a civilian project. No. It was sold to the public as, we'll be able to colonize the moon and we'll reduce the cost of a pound in space from $20,000 to $1,000. That was their goal. If you go back and look at the 1970s data, it wouldn't have gotten through Congress if they didn't have the support of the Defense Department. The space shuttle main cargo bay just happens to be the same size as a space laser weapon. Just a coincidence. If it weren't for the fact that the Defense Department was cheering on NASA and the committees in Congress, they wouldn't have gotten it approved, because you couldn't justify it on purely commercial reasons.