The crew of United Airlines Flight 497 declared an emergency landing   while the plane was at 4,000 feet 6 minutes after taking off due to the automated warnings of smoke in the equipment bay.  The electronic centralized aircraft monitoring (ECAM) system indicated an autothrottle-related message, then an avionics smoke warning message and instructions to land.  The plane returned to Louis Armstrong New Orleans International Airport.  The preliminary report by the NTSB released on April 7, 2011 indicated that there was no actual smoke or fire onboard the plane.

A computer glitch in the electronic centralized aircraft monitoring system resulted in a smoke warning.  The crew proceeded with an emergency landing.  The NTSB preliminary report indicated that there was no smoke or fire onboard.