The crew of an Atlas Air Boeing 747 inbound to the Miami International Airport from Brazil on the evening of 17 May reported that a portion of the aircraft's right wing, later found to be the forward inboard flap section, had separated from the right wing.
Due to the extent of the damage to the right side of the fuselage caused by the liberated flap, the US NTSB today classified the event as an accident and will investigate, according to an NTSB spokesman.
The accident comes as Atlas has been placed under close scrutiny by the US FAA for similar maintenance related problems. The agency on 5 May proposed a $506,150 penalty for carrier for flying with an improperly installed cockpit window that allowed depressurization on multiple flights, and for conducting multiple flights with an improvised engine pylon access door taped in place.
In February, a 68kg (150lb) composite flap assembly cover fell from an Atlas 747 inbound to Miami, an event the FAA continues to investigate. The detachment did not cause any injuries.
Involved in Monday's event was N498MC, an Atlas Air Boeing 747-47UF registered to Wells Fargo. Flight 8865, with two pilots on board had departed Campinas International airport in south eastern Brazil for Miami. The crew did not declare an emergency.
An FAA spokeswoman says the missing flap section was found 20 miles east of the Miami airport in an unpopulated area.