S.F. AIRPORT (Map, News) - It wasn’t until Jeff McNulty boarded his United Airlines flight last week that he realized he’d become a major breach of security at the busiest airport in the Bay Area.

The 36-year-old salesman waltzed right past several checkpoints at San Francisco International Airport, showing identification to at least three security screeners along the way, and was allowed on the plane with relative ease — and without a legitimate boarding pass.

The incident happened Wednesday night aboard United Flight 16 from SFO to John F. Kennedy Airport in New York. McNulty said he was issued a boarding pass meant for a man named John McNally. None of the airline and screening agents noticed or questioned that his identification did not match his ticket, he said.

“I thought back to all of the times I saw [airport security] frisk an old lady or take away my 4-ounce toothpaste and here I was standing on a plane without a valid boarding pass,” said the San Francisco resident.

Even a scanner at the United gate alerted an airline employee that something was wrong with McNulty’s boarding pass, he said. But the employee decided to override the computer and allow him to board the plane, he said.

Once on the plane, McNulty informed a flight attendant of the apparent mix-up and she discovered the airline had issued two of the same boarding passes, both for John McNally. She called McNulty a “security breach” and asked him to disembark the plane immediately, McNulty said. United officials eventually fixed the error and allowed him back on the flight, he said.

Passenger and baggage screening is handled at SFO by Covenant Aviation Security, a private company under contract with the Transportation Security Administration, the federal agency that supervises security at U.S. airports. Covenant has employed more than 1,000 security workers at SFO since 2002. Company officials did not return numerous calls for comment.

According to the Transportation Security Administration, McNulty was never a security breach. He and his baggage were checked for weapons and drugs as he passed through the checkpoints and he was not an imminent threat, said TSA spokesman Nico Melendez.

“We realize that the [security] process is susceptible to human error,” Melendez said.

Both Melendez and airport spokesman Mike McCarron said McNulty’s story, although unfortunate, was a “highly infrequent” occurrence and not something fliers should be alarmed about.

In a statement issued Tuesday, Jeff Kovick, spokesman for United, said “We will remind employees to follow the policies we have in place to ensure this rare occurrence is not repeated.”

maldax@sfexaminer.com