IT IS the stuff of science fiction - or sexual deviance - but it is almost certainly the future of airline security. Within the next five years air travellers around the world will have to step through full body scanners before boarding planes.
The scanners, which are being trialled by some airports in the US and Europe, are able to see through fabric and detect material hidden under clothes, and, in some cases, inside the body.
The Dutch Government has announced it will install the scanners in their airports for passengers boarding US-bound flights, after the Nigerian terrorism suspect Umar Farouk Abdulmutallab was apprehended on Christmas Day trying to blow up a flight between Amsterdam and Detroit.
Experts also predict the introduction of facial recognition technology that will be able to detect the finest physical features, even if a suspect has had plastic surgery, and match it with international police records.
But security experts experienced in the military, counter-terrorism and diplomacy say such technology will never make up for more usual intelligence methods. Surveillance, behavioural analysis and some form of profiling are, they say, the most effective ways of preventing terror attacks in the air.
''We now have the stomach, I believe, for profiling,'' Michael Carmody, a former Australian Army officer and former head of aviation security at the Federal Airports Corporation, said.
He refers specifically to behavioural profiling. ''For example, if someone, perhaps of certain background, goes into a travel agent and books a one-way ticket, no baggage and pays in cash, that is plugged into a security system that triggers warnings,'' he said.
Mr Carmody likens it to the security measures that kick in when a bank notices unusual or excessive transactions on customers credit cards when they are overseas. He says Australian authorities already share information on suspected terrorists through Interpol, the Australian Security Intelligence Organisation and the Australian Secret Intelligence Service.
''That needs to be interfaced with that [travel] environment,'' he said. ''There are various gateways in profiling that the person passes through, between booking a ticket and boarding an aircraft.''
Roger Henning, a former attache in the Australian embassy in Washington who now runs Homeland Security Asia-Pacific, said the system was fraught with problems because people could book tickets without any human contact. ''People can book online and use credit cards, which are themselves subject to identity theft. It's extremely easy to use someone else's credentials to get a ticket,'' Mr Henning said.
He also said frontline staff at airports were under extreme stress from passengers, often abusive about delays, and airline management that wanted a quick ''through-put'' of travellers. ''Passenger and air crew security have been compromised by the crass dash for cash by airlines,forcing passengers to self-check-in, all in a bid to save staff expense and make a profit,'' he said. ''Photo ID is not always requested, or offered, let alone checked.''
He said facial recognition technology could trace radical changes in appearance, including plastic surgery like that undergone by the late singer Michael Jackson. That could help detect suspects at airport counters.