What are these open panels underneath the wing root of a A380 (right above the person standing under the aircraft)? Are they ram air exhausts of the air conditioning packs?
1$\begingroup$ If nothing else, the included picture lends an awe to the size of the A380 compared to the crew person underneath. $\endgroup$– MilwrdfanAug 20, 2019 at 18:23
$\begingroup$ For other types / related post: What is this device below the door of a 737 (and other aircraft)? $\endgroup$– user14897Sep 1, 2019 at 19:19
They are indeed the Ram Air Outlet Doors.
(source, showing Ram Air Inlet (RAI) and Ram Air Outlets (RAO))
From the A380 FCOM (21 - Air Conditioning):
The hot bleed air flows into each pack, via the two pack valves, then enters the heat exchanger. This heat exchanger precools the air using external air. This external air enters through a ram air inlet door, and is then discharged overboard through two ram air outlet doors.
The reason they are located in the wing root is that the entire packs are in the wings. From this article:
The A380's wings are big enough that they can hold the plane's air conditioning packs. That, says Airbus, is an advantage over most other large planes because the packs don't have to be stored in the A380's belly fairing. That, in turn, means the plane's fuselage is more streamlined than it would otherwise be, reducing its drag.
$\begingroup$ Could you please expand RAM? Is it Random Access Memory or something related to Air cooling systems? Sorry, if my question seems silly. I am just starting to learn about flight systems. $\endgroup$– user42327Aug 16, 2019 at 16:14
2$\begingroup$ @Intellex it's ram as in ramming into something - the oncoming air rams into the inlet. $\endgroup$– pbfy0Aug 16, 2019 at 16:26
$\begingroup$ @pbfy0, Thanks for the information. I earlier thought this system is to cool the flight computers! Now learnt from wiki that this is a power generation unit. $\endgroup$– user42327Aug 16, 2019 at 16:34
2$\begingroup$ @Intellex There's something called a ram air turbine, which is an emergency source of power that extracts energy from oncoming air. However, according to the picture in this answer I think this is something different; this is just a source of cold air for the air conditioning system to dissipate heat into. $\endgroup$– pbfy0Aug 16, 2019 at 16:41
2$\begingroup$ @Intellex The ram air is called like that because it is not sucked into the aircraft by a fan or something similar, but is instead created by flying through the air fast enough to scoop it up (that is why the inlets are shaped like that). The RAT (Ram Air Turbine) is a propeller that can drop out of the fuselage in an emergency to generate electricity and hydraulic pressure. It is powered by ram air, hence the name, but is unrelated to the ram air for the air conditioning. $\endgroup$ Aug 16, 2019 at 16:52