What happened
On the day of the accident, a Boeing 747, registration HL-7451, arrived at London Stansted from Tashkent. Before disembarking, the flight engineer noted in the technical log that the captain's Attitude Director Indicator (ADI) was providing unreliable roll information, a detail also communicated to the ground engineering staff. While the aircraft was being prepared for its next leg to Milan-Malpensa, repairs were performed on the ADI. During this turnaround, cargo was exchanged, a new crew boarded, and the aircraft's takeoff weight was set at 548,352 lb with 68,300 lb of fuel onboard.
Following a one-hour delay caused by a missing flight plan, the aircraft was cleared to depart from Stand Alpha 6 and taxi toward runway 23. At 18:36, the aircraft received takeoff clearance under surface wind conditions of 190 degrees at 18 knots. Following the Dover 6R Standard Instrument Departure, the aircraft began its climb. As it passed 900 feet, the ADI comparator buzzer activated three times. The crew then noted issues with the DME indication as the buzzer sounded twice more.
While climbing through 1,400 feet, air traffic control instructed the crew to contact London Control. As the captain began the required left procedure turn, the comparator warning sounded approximately nine times. The aircraft reached a peak altitude of 2,532 feet amsl before entering a progressive left bank. The aircraft then entered a descent at high speeds, between 250 and 300 kt, striking the ground in a 90-degree left bank and a 40-degree nose-down pitch. There were 0 survivors.