The suspected bombing attempt aboard a transatlantic flight on Saturday will further dent public confidence in security as airlines struggle to attract passengers back after September 11th, aviation experts believe.
The man, identified as Mr Tariq Raja, is believed to be a Sri Lankan Muslim. He put up a fierce struggle before being subdued by passengers and staff. American investigators started an inquiry into the alleged suicide mission by the man, who was said to be carrying explosives in his shoes.
US authorities were trying to determine last night whether the man was acting alone or connected to a terror network, a US senator said. The flight was diverted to Boston on Saturday.
Mr Richard Shelby, a Republican on the Senate intelligence committee, said that the man, who carried a British passport identifying him as Richard Colvin Reid, born in 1973, "was trying to blow himself up, blow the plane up and we are very fortunate that it did not happen".
Mr Shelby, who said he had been briefed by the FBI, said federal authorities were taking the matter very seriously. "The message is that terrorists are going to hit us again. Is this part of a widespread deal or is this guy acting alone? We don't know yet.
"But I have to believe, from what I have been told, they were explosives in his shoes. I have to commend the crew, especially the stewardess, for acting as fast as they did."
Mr Kwame James, a 6 feet, 8 inch professional basketball player, said that a flight attendant had called out "we need some big guys back there real quick".
"I proceeded to help out, hold him down . . . He was unbelievably strong. You know, he at least fought off three or four of us," Mr James said.
The drama began when the suspect lit a match in mid-flight and apparently tried to set fire to his shoes. The flight had been routine for several hours, according to passengers.
Mr Raja refused lunch. Passengers said the female flight attendant jumped on Mr Raja after burning was reported by passengers. She screamed that he had bitten her, they said.
Mr James said a doctor on the plane gave the man an injection, "and then we tied him up with everything we could get our hands on, belts, just anything that could tie".
French officials said the suspect was turned away from Charles de Gaulle Airport in Paris on Friday, perhaps because he had no baggage to check in, but that he successfully boarded the American Airlines flight the next day after changing his identity.
Airline staff turned him away because he was "behaving bizarrely, was agitated and had a worrying look", French police said. His passport, issued in Belgium, appeared brand new, although police said that it had not been reported stolen. US immigration officials said they believed the passport to be a forgery.
Scotland Yard said last night that it believed Mr Raja was a British citizen. There were 185 passengers and 12 crew aboard the plane.
Aviation safety experts said the incident again highlighted the need for more stringent security checks.
While some airlines have introduced new measures since September 11, experts agreed that unless the industry brought in military levels of security breaches were bound to occur.
Even if it transpires that the man was not part of a terrorist group, the incident shows it is still relatively easy to smuggle some substances on board a plane. While hand luggage and some hold luggage is X-rayed, passengers are not.
Many airports, including Charles de Gaulle, largely rely on sniffer dogs to trace explosives. But the airport has only about 12 animals, not enough to patrol all areas 24 hours a day.
Dr Magnus Ranstorp, the deputy director of the centre for the study of terrorism at the University of St Andrews, called for "passenger profiling" to be introduced widely.
Airlines such as the Israeli carrier El Al subject passengers to in-depth questioning. If officials are at all suspicious, a passenger and his or her luggage are intimately searched.
Dr Ranstorp said a new centralised system of checking passports ought to be introduced in Europe to update the current "antiquated" system.