The First Boeing 747 Accident

The Boeing 747 performed its maiden flight in 1969. At the time, it was a true marvel of engineering - the largest, heaviest, and most capacious passenger aircraft ever built. Even today, it is surpassed in size only by the Airbus A380.

On November 20, 1974, a Lufthansa Boeing 747 was operating a scheduled service from Frankfurt am Main to Johannesburg, with a stopover in Nairobi. The flight to Nairobi (Kenya) proceeded without incident. There, a fresh crew took over. The aircraft departed Nairobi for Johannesburg with a light load - only 157 people on board.

The pilots and flight engineer completed the preflight procedures, taxied to the runway, deployed the flaps, and started the engines. Takeoff was initiated, and the aircraft lifted off at approximately 230 km/h.

Immediately after rotation, the aircraft experienced heavy vibrations. The climb rate was abnormally low, prompting the pilots to suspect an engine failure. However, the flight engineer reported that all four engines were operating normally. At the same time, the pilots began to feel shaking through their control columns - a classic sign of an impending stall.

The first officer was the pilot flying during takeoff. To prevent a loss of airspeed, he pushed the control column forward and leveled the aircraft at an altitude of about 30 meters (100 feet). To reduce drag, he also elected to retract the landing gear. However, when the large gear bay doors opened, drag increased dramatically instead. As a result, the aircraft began to lose altitude rapidly.

At a distance of 1,120 meters beyond the runway threshold, the aircraft made ground contact, bounced, and briefly became airborne again. After traveling another 114 meters, the 747 struck an embankment. The aircraft broke apart; the main fuselage and wings skidded along the ground for another 454 meters. The entire flight lasted just 16 seconds.

Once the fuselage came to a stop, the cabin crew began evacuation of passengers. However, a few minutes later, the fuel tanks exploded. In total, 59 people were killed - 4 flight attendants and 55 passengers. Another 54 sustained injuries. This was the first fatal accident involving a Boeing 747.

The investigation identified three main contributing factors:

- The crew failed to open the bleed valves. As a result, the pneumatic system did not activate the leading-edge slats, which are supposed to deploy in coordination with the trailing-edge flaps. Without the slats, the wings did not generate sufficient lift during takeoff.

- Nairobi airport is situated at an elevation of 1,600 meters (5,200 feet) above sea level. The air is thinner at that altitude, and on the day of the accident, it was also very hot. Under such "hot and high" conditions, more engine thrust is typically required for takeoff.

- The aircraft's takeoff weight was significantly below the maximum permissible weight, so the pilots elected to take off using reduced thrust settings in order to preserve engine life.

These factors collectively led to insufficient lift and an abrupt loss of altitude. The crew did not have enough time or altitude to identify the issue and recover. Compounding the situation was the lack of a slat configuration warning system. Following the accident, Boeing introduced such a system on the 747.

The investigation ultimately attributed the accident to the flight engineer, who failed to verify the position of the bleed valves. However, he was later acquitted in court. Nonetheless, both he and the captain were dismissed from Lufthansa “on medical grounds,” while the first officer was reassigned to less prestigious routes.