Incident Overview

Description
The Lufthansa Boeing 747-400 was undocked from the passenger boarding bridge at 22:55. It rolled along taxiways N5 and N towards runway 18. When a preceding Airbus A319 stopped on the runway, the B747-400 was decelerated at 23:10 to delay taxiing to the runway. The crew further stated that at the same time as braking on the right side of the track a violent loud blow was felt. After the takeoff of the A319, the crew slowly rolled onto runway 18 and then left via taxiway L. An inspection revealed that the right wing landing gear in the area of the trunnion, the rear mounting of the landing gear cylinder, was broken. There was also damage to the landing gear shaft and the landing gear flaps. Hydraulic fluid was leaking. The wing in the area above the landing gear had broken through. The outer skin of the fuselage above the right wing between station STA 1335 and STA 1350 at Stringer STR 21 level had penetrated inwards. The outer cylinder fracture was attributed to stress corrosion cracking. The outer cylinder in question was initially manufactured in 1976 for use on a Boeing 747-200. After 27750 cycles it was revised so it could be fitted on a Boeing 747-400.
Primary Cause
Stress corrosion cracking of the landing gear components, accelerated by age and subsequent revision to fit a Boeing 747-400.Stress corrosion cracking of the landing gear components, accelerated by age and subsequent revision to fit a Boeing 747-400.Share on: