Originally Posted by
Check Airman
Perhaps the Ground Spoilers were not armed for landing. After landing they extended automatically as per design logic and retracted automatically when the thrust levers were brought back from Reverse to Idle. It’s not normal to retract the Ground Spoilers manually so early in the landing roll out, which is why I suggest they retracted automatically when Idle was selected. Spoiler 5 was slow to retract, but perhaps that’s something to do with the auto retract logic?
Another possibility is that the Spoiler 5 extend actuator was still pressurised until it’s pressure was relieved by GRN HYD workload being transferred to the Flap retraction actuators.