On 15 April 2023, on a flight from Al Maktoum International Airport (OMDW) to Luxembourg Airport (ELLX), the Boeing B747-4HQF registered LX-ECV and operated by Cargolux Airlines International S.A. touched down on runway 06 at 16:30 UTC. Shortly after touchdown, the aircraft pitched down, rolled to the left and contacted the runway with the pods of the engines 1 and 2. The crew performed a go-around.
At 16:44 UTC the aircraft landed on runway 06 and taxied to apron P7. The crew was not aware of the double engine pod strike until after the flight, when maintenance identified the damage to the engine pods at the apron and reported it to the crew.
The operator informed the AET (Administration des enquêtes techniques) of the occurrence on 16 April 2023. On 17 April 2023, a visit of the occurrence aircraft took place with the operator, the DAC and the AET. The AET decided to gather further information related to the occurrence in order to gain a deeper insight of the event and assess:
- Whether potential systemic safety issues or safety lessons were likely to be addressed through a safety investigation;
- Whether there was a high probability of an accident.
Analysis of the data showed that from 5 s before touchdown, at a radar altitude of 68 ft, up to the first touchdown at 16:30 UTC, the aircraft experienced a wind shift with the airspeed first decreasing by 7 kts over a period of 2 s and subsequently increasing by 19 kts up to touchdown. These airspeed fluctuations can be traced to variable environmental conditions and could not be related to the control inputs of the pilot flying.
The ATIS from 15:50 UTC, which was used by the crew for the approach briefing, broadcasted a wind coming from 360° at 14 kts, variable between 320° and 040° and temporarily coming from 030° at 15 kts with gusts up to 25 kts. When the aircraft was cleared to land at 16:28:31 UTC, the wind information provided by the tower was out of 350° with 17 kts.
Although the crew was aware of the potentially variable wind conditions, landing in such conditions may be challenging because rapid changes are likely to be encountered in a highly dynamic phase of the flight – the landing. In the present occurrence, the situation was further exacerbated by a high approach speed related to the aircraft mass and an associated higher rate of descent (compared to aircraft with lower approach speeds) to follow the approach path. Reduced thrust on landing also limits the reactivity to corrective inputs due to the spool-up time of the engines. All this combined left the crew with only limited margin to react to changing environmental conditions.
After an evaluation of the collected information, the AET did not identify pertinent systemic safety issues or safety lessons and, taking into account similar occurrences to B747 aircraft, estimated that this event did not have a high probability of an accident. In terms of additional safety barriers, the observation is that in general, engineered defenses would be difficult to be implemented in this phase of flight and with regard to human performance, procedural defenses would likely have only limited effect in such a dynamic and demanding setting.
In coordination with the DAC, it was finally decided to classify the event as an “incident”.