The TSA has opened a new facility in Dallas where pilots known as Federal Flight Deck Officers can get re-certified to carry guns in the cockpit. After their initial training in New Mexico, pilots must undergo extensive training every five years to keep their certification current. Re-certification centers in Texas and New Jersey are run by the TSA without participation by the airlines, which are reportedly concerned about liability issues. But with only a limited number of commercial flights covered by federal air marshals, some pilots believe security is ultimately up to them. "That's my role, to be the last line of defense," said one pilot at the Dallas center. "I never want [terrorists] to get onto our aircraft again and do what they did."