On Nov 4th 2013 Germany's BFU reported in their monthly bulletin, that the aircraft was preparing for departure at 02:01L (00:01Z), 48960 live chicken one day old had been loaded as cargo. The APU was running, engine #1 had been started and was running, engine #4 was spooling up for startup when the crew heard a muffled bang. The first officer monitoring the APU had observed fluctuations of the rpms and a temperature rise of the APU, engines #1 and #4 were stopped, the APU was stopped and the fire extinguisher discharged. The captain instructed a flight mechanics to leave the aircraft through the emergency exit at the floor of the cockpit to check the exterior of the aircraft, the engineer reported subsequently that the APU was on fire. A second flight mechanics and the flight engineer left the cockpit and joined efforts to extinguish the fire, at 02:07L the radio operator advised tower of a fire on board and requested emergency services. At 02:08L observers around the aircraft noticed the fire, too, and observed a fluid leaking from the aircraft. The fire brigade was alerted at 02:08L and received their destination at 02:09L, the first vehicle reached the aircraft at 02:12L and began to foam the aircraft. The remaining cockpit crew left the aircraft through the emergency exit in the cockpit floor and vacated the area to safety. The aircraft burned down. The APU's gearbox made out of Magnesium was found completely burned away, the steel made cogwheels of the gear were found in the remains at the ground.
