Airport police said officers and a Transportation Security Administration agent smelled alcohol as they passed the pilot waiting to get on an elevator. The pilot was conducting preflight checks at about 6 a.m. when police boarded the aircraft, airport spokesman Patrick Hogan said.
Officers made him take a breath test and arrested him on suspicion of being under the influence of alcohol, Hogan said. Passengers had not yet boarded the flight to New York's LaGuardia Airport, he said.
The 48-year-old pilot was released several hours later to airline employees. Hogan said airport police will wait until blood tests are processed before deciding whether to file charges against him.
Federal rules prohibit pilots from flying within eight hours of drinking alcohol or if they have a blood-alcohol level of 0.04 or higher, half the level allowed for motorists. Police haven't released the pilot's initial test results.
The pilot has been suspended pending an investigation, said Matt Miller, a spokesman for American Airlines, which uses American Eagle to operate shorter connecting flights. Both airlines are owned by AMR Corp.
The company is cooperating with authorities and will conduct an internal investigation, Miller said.
A woman who answered the phone at a North Carolina number listed in the pilot's name referred inquiries to the Air Line Pilots Association, his union. She said he has been a member of the union for 23 years, but declined further comment.
Messages left with union officials were not immediately returned.
The flight, with 53 passengers on board, was delayed about 2 1/2 hours while a replacement pilot was arranged, Miller said. It arrived in New York after noon.
The pilot was taken to Fairview Southdale Hospital to have a blood sample taken, then was returned to airport police before being released, Hogan said.
Pilots face drug and alcohol testing when they seek a job, are involved in an accident or return from alcohol rehabilitation. Some are selected for random tests. More than 10,000 pilots are tested each year and about a dozen flunk the alcohol part—a number that has remained mostly steady for more than a decade, according to federal statistics.
Twelve pilots failed the breath test in 2011, 10 in 2010, and 11 in 2009, according to the Federal Aviation Administration.
"Your odds of having an impaired driver on the highway are much higher, but there's a smaller margin for error in aviation," said James Hall, former chairman of the National Transportation Safety Board.
Drinking among pilots got more attention after notorious cases in the 1990s, including one in which a jury convicted all three pilots of a Northwest Airlines flight of flying under the influence. Federal rules were tightened as a result.
Hall said most airlines and other transportation companies now have effective programs to identify and get treatment for employees with drug or alcohol problems. But, he said, an incident like Friday's should lead to a re-examination of protocols, including the 0.04 percent standard to testing procedures.