Raleigh, N.C. — A day after a disoriented man was found aboard a Delta Airlines jet at Raleigh-Durham International Airport, security experts are questioning the airport's security system.

The man climbed a barbed wire fence at the perimeter of the airport and boarded an empty plane, where a cleaning crew found  him at about 3:30 a.m. Tuesday and turned him over to police, authorities said.

Gregory Scott Wester, 32, of 30 Old Mill Road in Fuquay-Varina, has been charged by RDU police with first-degree trespassing and possession of a controlled substance, authorities said. The FBI and the Transportation Security Administration also charged him with access to an aircraft without permission.

Wester is being held at the Wake County Jail and is scheduled to appear in federal court on Friday.

RDU spokeswoman Mindy Hamlin downplayed the security breach Tuesday, saying no one was harmed in the incident and that the various layers of security at the airport worked together to thwart any threat to people or aircraft.

But David Schanzer, the director of the Triangle Center on Terrorism and Homeland Security, said relying on cleaning crews and other personnel to catch potential hijackers isn't good enough to ensure safety.

"If we are just relying on a fence and having people notice, that's not really good," Schanzer said. "To have excellent security, you need to have a much more automated system that will detect these types of entries and notify people in real time."

Durham-based Knowledge Vector has created such a system, and it is being tested at Reagan National Airport in Washington, D.C. When a sensor is tripped, software determines the credibility of the threat and immediately notifies the closest first responder if it determines the threat is real.

Knowledge Vector Chief Executive Lee Bryan said he believes the system could have prevented the security breach at RDU.

"The video subsystem would have been deployed with a pan-zoom-tilt camera to pick him up. We would have a picture of him before he even got near the tarmac," Bryan said.

"Obviously, something fell down in the (RDU security) system to even get close to the airplane," he said.

Although the 7-foot-high, barbed wire fence around RDU meets TSA requirements, Hamlin said, airport officials are reviewing security procedures. They already planned to update the security system for entry into some doors and gates and are looking at whether changes should be made to the perimeter fencing as well, she said.

"We will make changes and refinements as needed," Hamlin said.