Air travelers in the US can expect to be monitored, probed -- and hopefully protected -- by a handful of new security technologies, from chemical-sniffing detectors to computer cameras that scan crowds.
The devices could be installed in relatively short order at airports and on planes, aiming to keep hijackers and weapons from getting on board, and disarming those who do, experts say.
Fliers could pay for the measures with a US$30 to US$50 a ticket surcharge, one expert estimated.
Agencies that handle security at airports, including the Federal Aviation Administration, US Customs Service and the US Immigration and Naturalization Service, had little to say about technology upgrades under consideration.
But experts point to a combination of devices that screen luggage, clothes and criminal backgrounds.
The first line of defense is aimed at keeping weapons and explosives off planes, said Rick Charles, who heads the aviation program at Georgia State University.
Travelers can expect more frequent searches of luggage, documents and clothes with particle detectors that can find traces of drugs or explosives and, in some cases, pathogens used in biological warfare, he said. Authorities will also probably call for more explosives-detecting resonance scanners that can hone in on tough-to-find plastic explosives, said Billie Vincent, president of Aerospace Services International and the FAA's former head of security.
Machines that can find bombs and guns provide no defense against passengers bent on destruction by other means -- such as the suicide-minded groups that hijacked the four airliners on Sept. 11.
To screen passengers, aviation authorities are considering biometric scanners that check identities against criminal records and terrorist watch lists, Charles said.
``Biometrics attempts to keep the wrong people off airplanes, instead of trying to keep bombs and weapons off airplanes,'' said Charles.
Face-recognition systems show promise in matching terrorists' mug shots -- garnered from files of the FBI, CIA or Interpol -- to faces roaming airport crowds. One such system was installed in June at Iceland's Keflavik International Airport. Others are under consideration here.
Biometric systems are already in use by Customs and the INS. The INS' INSPASS system uses hand-geometry scanning kiosks to permit entry to registered travelers. And Customs' new border-crossing cards for Mexicans store fingerprint data. Charles said fingerprint identity checks may also appear at check-in counters, where travelers' names and thumbprints are checked against watch lists and criminal records.
But without a US criminal record -- or at least a photo and some background information -- a terrorist will not be intercepted by a biometric security system.
``What if he's not in anybody's database? He'll walk right through,'' said Robert Mannal, of KPMG's information risk management office.
Security measures being proposed for aircraft themselves take this reality into consideration.
In Cleveland, ADR Investigation and Protection Corp. is discussing installing closed circuit television systems on the jetliners of three airlines, said company president Lex Rosenbaum. He would not name the carriers.
The systems would allow pilots to keep an eye on the passengers while sending streaming video to ground stations, where it could be monitored or stored for a later investigation, Rosenbaum said.