Northwest Airlines Flight 253

aka Christmas DayBombingAttempt

Northwest Airlines Flight 253 was an international passenger flight from Amsterdam Airport Schiphol in Amsterdam, Netherlands, to Detroit Metropolitan Wayne County Airport in Romulus, Michigan, United States. The flight was the target of a failed AlQaeda bombing attempt on Christmas Day, December 25, 2009, in which a passenger tried to set off plastic explosives sewn to his underwear. There were 290 people on board the plane, which was operated by Northwest Airlines... The suspected bomber in the "Christmas Day bombing attempt"[2] was 23-year-old Umar Farouk Abdulmutallab, who had concealed plastic explosives in his underwear but failed to detonate them properly.

http://en.wikipedia.org/wiki/Northwest_Airlines_Flight_253

Bruce Schneier post. The security checkpoints worked. Because we screen for obvious bombs, Umar Farouk Abdulmutallab -- or, more precisely, whoever built the bomb -- had to construct a far less reliable bomb than he would have otherwise. Instead of using a timer or a plunger or a reliable detonation mechanism, as would any commercial user of PETN, he had to resort to an ad hoc and much more inefficient homebrew mechanism: one involving a syringe and 20 minutes in the lavatory and we don't know exactly what else. And it didn't work... We're going to install full-body scanners, even though there are lots of ways to hide PETN -- stuff it in a body cavity, spread it thinly on a garment -- from the machines. We're going to profile people traveling from 14 countries, even though it's easy for a terrorist to travel from a different country. Seating requirements for the last hour of flight were the most ridiculous example. The problem with all these measures is that they're only effective if we guess the plot correctly.