Over the last year, 3 million travelers have zipped through special airport security checkpoints without having to remove their shoes, belts, coats or unpack their laptop computers, according to federal officials.
They were participants in a program run by the Transportation Security Administration to let pre-screened, frequent travelers avoid long lines at security checkpoints at the nation's airports.
The program, called PreCheck, began in October 2011 and has expanded to 26 airports and five airlines: Alaska Airlines, American Airlines, Delta Air Lines, United Airlines and US Airways.
The latest expansion of the program was last week at Dulles International Airport outside Washington.
"We anticipate that TSA PreCheck will screen a total of about 5 million passengers by the end of 2012, a key milestone as TSA strives to implement a more risk-based approach to security," TSA Associate Administrator Doug Hofsass said in a statement.