What I find most disturbing about the incident, in hindsight, is what happened after the first replay of the explosion. A highly experienced fuel-system technician muttered "o-ring?", followed by nods from three other highly experienced aircraft maintenance technicians. Over the next few months, I noted a sharp rise in o-ring replacements billed through my squadron's supply accounts. (One of my administrative duties was ensuring that the squadron's operations and maintenance budget remained somewhere close to actual expenditures.) There was no maintenance bulletin; no formal training program; just the "shared awareness" in the maintenance community of a potential source of problems. Although an o-ring failure on that aircraft could not possibly have had the same catastrophic consequences as it did for Challenger, nobody likes an aircraft being labelled "not mission capable."