(ABC News) Safety experts are stunned after a passenger plane filled with smoke while trying to land at a snowy Denver International Airport, but the air traffic controller dismissed the call for help from the pilot as “B.S.”

The April 3 flight from Peoria, Ill., was scheduled to land in Denver. Everything was going according to plan until smoke filled the plane. The pilot of the United plane called the control tower to request an emergency landing.

Note: Read our discussion guidelines before commenting.