How feasible was it for terrorists to mix together a few common chemicals into a big sky kablooie? People far smarter than us investigate. (Thanks to Caitlin!)
Once the plane is over the ocean, very discreetly bring all of your gear into the toilet…put a beaker containing the peroxide / acetone mixture into the ice water bath, and start adding the acid, drop by drop, while stirring constantly.
After a few hours – assuming, by some miracle, that the fumes haven’t overcome you or alerted passengers or the flight crew to your activities – you’ll have a quantity of TATP with which to carry out your mission. Now all you need to do is dry it for an hour or two.
Just don’t accidentally bump the call button while you’re puttering around.
“Mass murder in the skies: was the plot feasible?” [The Register]