The airline issued the following statement:
"An American Airlines pilot was arrested at London Heathrow airport yesterday (Wednesday, 20 May) having failed a breathalyser test. Police had been called by airport staff working at the security control post.
The male pilot was due to operate flight AA87; the 10.15 London - Chicago scheduled service. The pilot was replaced and following a delay, the flight departed at 11.30am. No other operations were affected by the incident.
"American Airlines' primary concern is for the safety and comfort of our passengers and crews. The company has strict policies on alcohol and substance abuse and holds its employees to the highest standards. Employees at all levels of the company are not allowed to be on duty whilst under the influence of drugs or alcohol and regular screening is carried out. Support is available for those employees who seek help for problems with substance abuse.
"American will not be releasing any personal details of the pilot involved."