Agree with the comment about what and where things get through. There was an article in the newspaper here in NZ where a passenger boarding a domestic flight watched as security took some knitting needles of an old lady as she went through security, then when he was on the plane he could smell petrol. He brought this to the attention of the crew who searched and found another passenger had carried a chainsaw on in his carry-on luggage and it was leaking petrol. The passenger with the chainsaw said that security had noticed the saw, but had checked their list of banned items and told him chainsaws were not listed so he was fine!