WASHINGTON, May 1 (Reuters) - The U.S. Transportation

Department said Thursday it is taking steps to retain and

recruit more air traffic controllers to address a significant

staffing shortage.

The Federal Aviation Administration, which said earlier it

plans to hire 2,000 air traffic controller trainees this year,

said it will offer retirement-eligible controllers who are under

the mandatory retirement age of 56 a lump sum payment of 20% of

their basic pay for each year they continue to work.

A persistent shortage of controllers has delayed flights and

many controllers are working mandatory overtime and six-day

weeks. The FAA is about 3,500 air traffic controllers short of

targeted staffing levels.