Read this post and go to gaol
To blow up a passenger airliner you will need the following:
1) A large canister full of petrol
2) A match
Alternatively, just go for 3) A bomb of some description.
The difficult bit is smuggling the bastards onboard and positioning them somewhere where they can do maximum damage. But let's not concern ourselves with that. The very fact that you know HOW to blow up a plane means you can be sent to prison for six years.
Please note: this judgement comes from the self-same Northern Ireland which has seen the release of dozens of proven and convicted terrorist murderers over the last few years.
(And now let the outraged "you're missing the point" attacks commence in the comments...)