Preliminary investigations into the Lufthansa Airbus A320 wing-strike incident at Hamburg during a storm two months ago show that the twinjet was under dual control at a critical point of the landing, following an approach conducted by the less experienced of the two pilots.
Initial information into the 1 March landing, released by German investigation agency BFU, says that flight LH044 from Munich was established on the instrument landing system approach to runway 23 when Hamburg tower informed the crew of 28kt (52km/h) crosswinds, gusting to 47kt.
BFU's preliminary report contains an excerpt from the quick-reference handbook giving a 30kt limit for a manually flown crosswind landing. The 2min average wind for Runway 23 was 33kt, although the 300° bearing would have lowered the crosswind component.
While the captain had over 10,200h flight experience, with more than 4,120h on type, the crew had previously agreed that the sector would be flown by the 24-year-old co-pilot, who had accumulated just 579h with 327h on type.
The pilots were told that 50% of approaches in the previous 10min had resulted in a go-around. Tower controllers offered the alternative Runway 33, but the crew declined. The pilots, however, were prepared for the possibility of a missed approach.
Flight-data recorder information shows that, in the final moments of the approach, both pilots were applying sidestick input. A320 aircraft are able to accept dual input the inputs from the two sidesticks are numerically summed.
At a height of 75ft (25m) the aircraft began to drift to the left, and the co-pilot moved the sidestick 10e_SDgr right, while at 50ft the sidestick was moved left accompanied by a 28e_SDgr left-rudder input. The captain gave 4.5e_SDgr right-hand input to his sidestick at 15ft, and the co-pilot also moved her sidestick from left to right.
The aircraft banked 4e_SDgr left, touching down briefly with the left main landing-gear, before the roll angle increased to 23e_SDgr left and the wing-tip struck the runway.
While the crew had noticed the lifting of the right wing, neither realised the aircraft had contacted the ground. Both the co-pilot and the captain deflected their sidesticks to the right, and there was 14e_SDgr right-rudder input.
The co-pilot called a go-around, which was confirmed by the captain, and then the captain took full control of the aircraft by pressing his sidestick button to transfer input priority.
After completing the go-around the captain returned control of the aircraft to the co-pilot, who conducted a localiser-DME approach to Runway 33 and landed without further incident. None of those on board were injured.
The wing-strike occurred at about 450m from the Runway 23 threshold and damaged the A320's wing-fence, slats and guide tracks. "A runway inspection was then carried out but no parts were found," says the BFU.
It has not completed its investigation into the incident and has yet to reach any conclusions about the event. Lufthansa says both pilots are still employed by the airline.
Source: Flight International