Top FAA air traffic control official stepping down, sources say

WASHINGTON, April 8 (Reuters) - The head of the Federal Aviation Administration's air traffic organization is stepping down after more than 35 years with the agency.

Tim Arel, who is chief operating officer of the FAA Air Traffic Organization, has decided to take part in the USDOT's voluntary deferred retirement program, sources told Reuters. Questions have been raised about why the agency did not address concerns about close calls between helicopters and airplanes near Reagan Washington National Airport before a Jan. 29 fatal collision between an American Airlines AAL.O regional jet and Army helicopter killed 67.