I had my carry on pulled for a secondary scan on Thursday, and it flagged positive for explosives. I'd already been waiting for ten minutes for the bloke's bag in front of me to be searched. They do operate at glacial speeds.

After it had turned up positive, I had my passport and boarding card confiscated while they took the bag apart swiping every nook and cranny, taking as much time as they could about it.

Needless to say, despite all this fannying around, the second test came up negative and I was left to go on my way. I would say security for me that day took 45 minutes. And behind me other folks were getting increasingly p!ssed off while the operatives took their time about it. Although I was pretty relaxed about it as I'd arrived at T-3, one lady behind me made a complaint about the delay, understandably. I'd say she'd been waiting 20 minutes for her secondary bag search before the obvious backup had been made clear to the planks that "manage" the lines.

A shame those clipboard carrying time and motion idiots had not been there, they might've got a mouthful.

The same bag with the same contents has since gone through four other airport security checks without a problem.

As an opposite extreme example on the same trip, I transited HKG yesterday and there were 100 people in front of me in a security line with only two scanners. I feared the worst, but it took all of five minutes to clear. The staff were doing everything they could to speed the process along. A shame the same cannot be achieved at LHR.