In an effort to reduce long waits for travelers, the government is hiring more security screeners for dozens of airports, including Dallas-Fort Worth, Miami, New York's JFK and Washington's Dulles. Other airports, deemed overstaffed, will lose screeners.

The Transportation Security Administration (search) is trying to come up with the right number at 445 commercial airports as the busy summer travel season approaches. U.S. air carriers expect 65 million passengers each summer month. That's 12 percent more passengers per month compared to last summer.

This is the third time the TSA has reallocated screeners since it staffed every airport with federal workers on Nov. 19, 2002. Previous changes came about because Congress reduced the number of full-time screeners the agency could employ to 45,000 from about 60,000.

Mark Hatfield, TSA spokesman, said on Monday that the agency will continue to fine-tune staffing levels at airports.

The agency is hiring more than 100 new screeners at some airports that have experienced long lines at checkpoints. Those include Dallas-Fort Worth International Airport, Newark Liberty International Airport, Miami International Airport, New York's John F. Kennedy International Airport, Orlando International Airport and Washington's Dulles International Airport.

Others will lose screeners because they have too many. Among them are Pittsburgh International Airport, Piedmont Triad International Airport in North Carolina, New Orleans International Airport, Jacksonville Airport and Cleveland Hopkins International Airport.

"We're hoping to achieve those through attrition in the coming months," Hatfield said.

David Plavin, president of the airport trade group Airports Council International-North America (search), said the fledgling agency has shown it doesn't have enough experience in airport management to know how to staff screening checkpoints.

"It doesn't strike me that the federal government has figured out a way to be flexible enough to have enough people there when the passengers are there," Plavin said. Airports need more seasonal and part-time workers to cope with changes in traffic, he said.

Doug Wills, spokesman for the Air Transport Association (search), said the airline trade group isn't certain how TSA came up with its staffing formula.

"We, in general, felt that more staffing decisions should be made at the local federal security director level," Wills said.

The group is uneasy that centralized hiring decisions made in Washington result in long delays in hiring screeners.

Hatfield said federal security directors who manage the screeners helped make the decision on how many screeners to allocate.