German investigators found that the nose landing gear downlock pin was not installed before a Lufthansa Boeing 787-9 retracted unexpectedly at Frankfurt Airport on June 4. The German Federal Bureau of Aircraft Accident Investigation said 23 people were injured, including two seriously, and the aircraft was substantially damaged.
Technicians Conducted Maintenance Test
The Lufthansa 787 had arrived from Austin, Texas, and was being prepared for a flight to Los Angeles. Two technicians were troubleshooting an unresolved issue involving the main landing gear doors when the nose gear retracted immediately after they moved the landing gear lever.
Proper maintenance procedures directed technicians to install the landing gear downlock pins before operating the lever. Investigators found the nose gear pin and its red warning flag inside a storage box in the avionics compartment. Four downlock pins had been installed correctly on the main landing gear.
Aircraft Struck High Loader
The Lufthansa 787’s nose, along with both engine cowlings, struck the concrete below. The forward fuselage also pressed down on a cargo high loader, injuring one person and damaging the loader and cargo-door area.
Recovery crews drained about 60,000 kilograms of fuel before they lifted the nose back up with an air cushion. The nose gear extended and locked as the aircraft was raised. The BFU has not issued a probable-cause determination, and the investigation remains open.
