Cargo doors sound

[Swisspilot1986]

It makes no sense to hear the doors motors from the cockpit, especially when all windows and doors are closed

[sunake]

Are you sure you're not hearing the hydraulic pump that operates the cargo door? 

[Swisspilot1986]

good question. I've to search where is this pump located. It seems strange to me, or can a licensed pilot confirm?

[sunake]

Yeah it's definitely the ground hydraulic pump. I'm guessing it's a smaller pump that allows ground crew to operate things like the cargo door and gear bay doors. You can see the blue ON light on the GND HYD section on the overhead go on and off as the sound plays and stops. 

[Swisspilot1986]

yes, we also can switch this GND HYD section on from the cockpit, so both hyd can be pressurized and we hear the same noise when the cargo doors open

[Farlis]

On 3/29/2025 at 9:33 PM, Swisspilot1986 said:

good question. I've to search where is this pump located. It seems strange to me, or can a licensed pilot confirm?

They have Pablo on the team. He flies the A350 in real life. You should trust he knows what should be audible and what isn't.

As aspected there has been ongoing discussion on what you hear of the flaps movement. A lot of armchair pilots with no experience sitting in the A350 flightdeck questioning whether you can really just hear the slats motor.

Now the same about the hydraulic pump of the cargo doors.

[Swisspilot1986]

When airplane doors are open but cockpit door is closed you even hear the APU from the cockpit, so the thrust from my armchair can be discussed.