WASHINGTON (AP) -- There is more turbulence at the agency charged with airport security since the Sept. 11, 2001, terrorist attacks: The Transportation Security Administration is losing its third director in as many years.
TSA chief David Stone will leave the job in June, spokesman Mark Hatfield said Friday. No reason for the move was provided and no replacement was announced.
The change comes as the new Homeland Security secretary, Michael Chertoff, is considering restructuring the entire department, which includes TSA.
Stone, a retired Coast Guard admiral, was preceded by James Loy, former commandant of the Coast Guard, and John Magaw, former head of the Secret Service. Stone's 16-month tenure as TSA chief was the longest.
Sen. Susan Collins, R-Maine, chairwoman of the committee that oversees Homeland Security, said Stone ran TSA during a critical time, ''when the challenges of securing our transportation infrastructure have taken on a great urgency.''
''He did a good job,'' said Rep. John Mica, R-Fla., chairman of the House aviation subcommittee. ''I worked well with Admiral Stone.''
Mica has criticized the TSA for being a ''Soviet-style bureaucracy'' with too many airport screeners who don't perform well enough detecting explosives and dangerous items on passengers. He wants to see the agency transformed so that private companies take over airport screening and the TSA simply oversees the private companies.
''TSA did a great job in putting an army of 48,000 screeners together, but then when you stand back and look at the results, the performance is just not acceptable,'' Mica said.
He said he's concerned that it will take time to replace Stone, which will slow down efforts to restructure the TSA.
Oregon Rep. Peter DeFazio, formerly the ranking Democrat on the aviation subcommittee, said there are not enough screeners and they are hampered by dated equipment. He opposes a return to private screeners, who were widely criticized for their poor performance in the aftermath of the Sept. 11 hijackings.
Airports already have the option of using private screeners, but only one airport - in Elko, Nev. - has gone that route. Five other airports have been part of a pilot program to use private screeners since the TSA assumed the responsibility for airport security.
Bruce Schneier, who has written a book on security technology and serves on a TSA advisory committee, said privatizing screeners won't improve their performance.
''A private company will want to wring efficiencies out of the system, and inherently security is not an efficient system,'' Schneier said.
Schneier said better training, management and equipment are needed for screeners to do a better job.
''It may be with the current state of equipment, you just can't do it,'' Schneier said.
President Bush has proposed folding some of TSA's responsibilities into Homeland Security - most notably Secure Flight, a computerized program to screen for terrorists. Already, the federal air marshals have moved to another agency within Homeland Security.
James Carafano, a homeland security expert with the Heritage Foundation think tank, said too much has been expected of the TSA in too short a time. In a matter of months, the agency grew from a handful of people in Washington to tens of thousands of employees throughout the country and installed bomb-detection equipment in every airport.
''You look at all the things demanded of TSA, the short timeline and the enormity of it, it's still a place that's filled with a lot of dedicated people, up and down the line,'' Carafano said.