A breach that allowed 11 people to walk through an unattended security checkpoint lane at one of the nation's busiest airports has some travelers scratching their heads about how this could happen even with the enhanced security measures put in place after the Sept. 11 terror attacks.
The incident Monday at Kennedy Airport is being investigated by the Transportation Security Administration, the agency that was created to protect the nation's airports after the 2001 attacks. The TSA said three passengers did not receive required secondary screening after they set off the metal detector at the unmanned checkpoint lane.
At Boston's Logan International Airport - a staging point for two of the jetliners used in the 9/11 attacks - some travelers said they were surprised that a checkpoint lane could be left unattended at any airport.
"Mistakes happen, but they're (TSA workers) supposed to be there to protect our lives," said Kylie Welsh, who returned to Boston from a trip to Pittsburgh on Wednesday.
The TSA said in Monday's incident that all carry-on bags received required screening and that it was confident the incident presented "minimal risk to the aviation transportation system."
Post-9/11 security procedures include body scans, pat-downs, fortified cockpit doors, screening of checked luggage for explosives and a ban on large containers of liquids to prevent anyone from making an improvised explosive device during flight.
This isn't the first time travelers who weren't properly screened slipped through airport security.
- In 2002, hundreds of passengers were evacuated at Fort Lauderdale-Hollywood International Airport in Florida after a metal detector was found unplugged. About 300 passengers were rescreened and allowed back into the concourse.
- In 2014, a woman who had been arrested multiple times for trying to sneak onto planes managed to slip onto a flight from San Jose to Los Angeles without a ticket.
- In 2015, a Texas man walked through a security checkpoint without a ticket or identification at Dallas-Fort Worth International Airport and ran onto an American Airlines flight bound for Guatemala. He was arrested on a criminal trespassing charge.
"Unfortunately, it's not as rare as it sounds," said Jeffrey Price, a professor of aerospace management at Metropolitan State University in Denver and author of the 2008 book, "Practical Aviation Security: Predicting and Preventing Future Threats."
"The biggest thing I don't understand is why would everybody just walk away? What went wrong that that last person figured they could just wander off and leave the checkpoint abandoned?" Price said. "I'm sure every TSA person there knows you just don't walk off and leave an access point open."
A TSA spokesman declined to say whether any employees have been disciplined, but said the investigation into the incident is ongoing.
Bennet Waters, a former deputy assistant administrator of TSA, said the incident at JFK should not cause a crisis of confidence in airport security.
"I think it's fair for the flying public to be concerned any time a (security) layer is breached, but I think that concern has to be bound with the realization that there are multiple layers in the TSA security regime in use at all times," Waters said. "In fact, the system is designed so that a failure in any one layer does not constitute a failure in the system at large."
Douglas Kidd, executive director of the National Association of Airline Passengers, said any kind of security breach at airports should not be tolerated.
"A properly run organization would not have security breaches. It's as simple as that," Kidd said.
Colleen Furber, who was waiting in Boston to board a plane to Florida on Wednesday, said she gets concerned when she reads about people and items - including weapons - making it through airport security without being detected.
"I think it happens more than you know. Obviously, a lot of things get through on a regular basis," she said. "It creates anxiety for the traveling public."
But Furber said she said it won't stop her from flying.
"I wouldn't put my life on hold," she said.