Created Thursday, Nov 14th 2024 20:25Z, last updated Thursday, Nov 14th 2024 20:25Z
A West Atlantic UK Boeing 737-400 freighter, registration G-JMCZ performing flight NPT-10 from London Stansted,EN to Edinburgh,SC (UK) with 2 crew, had been enroute at FL280 when the crew started their descent into Edinburgh. At that point the cargo shifted and came into contact with the forward bulkhead. The aircraft continued for a landing without further incident.
ON Nov 14th 2024 the AAIB released their bulletin concluding the probable causes of this serious incident were:
During the start of the descent for landing at Edinburgh, the ULD loaded in Bay B shifted forwards, hitting the forward bulkhead wall. The ULD was found in Bay A when the cargo was unloaded on arrival. It is likely that the locks on the ULD loaded in Bay B were not secured as required, allowing the ULD to move during flight. The operator made a number of changes to address the risks of cargo shifts and of void bays in particular.
The AAIB stated:
Examination of the forward bulkhead revealed some minor damage to the liner tape and paint. There was no damage to the main door bulkhead, door, or the cargo handling system.
The AAIB summarized the sequence of events:
When the crew began their descent on the flight from London Stansted Airport to Edinburgh Airport, they heard what they described as a “dull double bang.” All the engine indications were normal except a momentary higher vibration indication on the right engine.
There had been previous reports of sporadic indications on this engine and the crew considered the possibility that the engine had surged but there were no further indications.
The crew also considered that there may have been a cargo shift on the main deck. Having completed their decision-making process, they elected to continue to Edinburgh where the aircraft landed safely without further incident.
Once the aircraft was parked on the stand, the main cargo door was opened and cargo unloading began immediately. The crew were informed by the ground crew that a unit load device (ULD) that had been loaded in Bay B in the aircraft was found in Bay A.
The AAIB analysed:
During the start of the descent into Edinburgh, the ULD loaded in Bay B moved forward into Bay A and struck the forward bulkhead. Although the crew initially considered that the noise might have been associated with an engine after they noted an abnormal vibration indication, they concluded that they may have had a cargo shift. Due to the cargo being unloaded before the crew had completed their post-flight actions, it was not possible to establish which locks, if any, had been secured on the ULD before the flight departed from Stansted or if the locks malfunctioned in some way. There was some minor damage to the bulkhead and no damage to the cargo loading system. The aircraft centre of gravity remained within limits and the crew experienced no limitations in control or handling. The aircraft landed at Edinburgh without further incident.
The cargo was loaded at Stansted leaving Bay A as a void. Given the lack of space within the main deck, it is not possible for anyone to check the security of the load or the position of the locks once the cargo is loaded. It is only possible to check the front locks of the forward most ULD and any void space in front of that. The check of the locks therefore must be done for each ULD or pallet as it is loaded. It is likely that during the loading of the ULD in Bay B, either some or all of the locks were not secured, and this allowed the ULD to move forward into Bay A when the aircraft pitched down for the descent.
The operator’s procedures place the ultimate responsibility on the commander (or a delegated crew member) to ensure the security of the load, but it is difficult to see how this can be complied with unless each individual ULD or pallet is checked as it is loaded. The operator’s procedures also require the cargo handling person responsible for the loading to sign to confirm that the load is secure. All these procedures were to be reviewed by the operator as part of the safety action group review. A new version of the LIR was already in use at the time of publication to make clear the responsibilities of all parties in ensuring the load is secure. It also required all the parties to acknowledge and sign for the security of void bays in that all floor locks have been raised.
