Accident investigators are trying to determine which cargo aboard the Boeing 747-400 was located just forward of the starboard wing, where the fire broke out. Investigators are also checking if there were any lithium-ion batteries in that location. Lithium-ion batteries are volatile and if defective, or improperly packed, can overheat or short-circuit, potentially leading to a fire.
The fire's location was identified so quickly because the plane was equipped with an automated maintenance diagnostic system, which transmitted data about a serious problem in the hold by satellite to the airline's operations center in Louisville, Ky., the AP said.
The plane's pilots also told air traffic controllers that a fire had broken out in the main compartment and smoke made it difficult to read their instruments, people familiar with the investigation told the news agency.
The investigation is being led by the United Arab Emirates' aviation authority with assistance from the U.S. National Transportation Safety Board.
U.A.E. authorities said the crew reported smoke in the cockpit about 20 minutes after taking off from Dubai on a flight to a UPS hub in Cologne, Germany. The plane failed to make an emergency landing on its first try and crashed inside a U.A.E. military base.
