A320 Overboard Vent [Archive]

Bubi352

26th Jan 2015, 00:40

What are the two overboard vents (left and right side) for on the following picture? I believe it is the overboard vent for the forward lavs but I can't find any reference to it. Could someone enlighten me. Thank you.

http://s15.postimg.org/8a8sdfx8n/IMG_2080.jpg (http://postimg.org/image/8a8sdfx8n/)

LEVEL600

26th Jan 2015, 08:37

Exhaust of cooling air from blue and yellow elec. hydraulic pump.

IFixPlanes

26th Jan 2015, 09:01

Agree... :ok:

CISTRS

26th Jan 2015, 13:35

But it's a secret.

Bubi352

26th Jan 2015, 18:43

Thank you! I knew there were some sharp guys out there. Where is the one for the green hydraulic?

Peter G-W

26th Jan 2015, 18:56

Ah, yes, the secret Green electric pump?

LEVEL600

26th Jan 2015, 18:59

Green system is pressurized from engine driven hydraulic pump only, there is no elec. pump or if yes, than is too secret for me :).

PilotsOfTheCaribbean

26th Jan 2015, 19:02

Irony lost! ;)

However the Green system is also pressurized from the Yellow system via the PTU, so that isn't entirely correct.

LEVEL600

26th Jan 2015, 19:14

Yes, good notice. You are absolutelly right, pressure source for green system are EDP and PTU.

AeroTech

1st Feb 2015, 08:31

Hi,

Exhaust of cooling air from blue and yellow elec. hydraulic pump.

Agree...

I am not familiar with A320. Can you please explain "exhaust cooling air"?

Is it related to pressurization of hydraulic reservoir?

For example the reservoir pressurization system of hydraulic system in B737 is fitted with vent through the relief valve and the drain mast. Also in b737 the Skydrol is cooled through heat exchanger in the fuel tank.

Feedback appreciated.

LEVEL600

1st Feb 2015, 08:52

On A320 contrary to 737 EMDP is electric motor of pump cooled by air flow, which is produced directly by fan mounted on motor shaft . Pump itself is cooled by hydraulic fluid like on Boeing, only without heat exchangers in fuel tanks.

AeroTech

1st Feb 2015, 16:11

LEVEL600, thank you.

How the EDP is cooled in A320? I mean case drain of EDP.

It will be nice if you can post schematic(s) (from AMM or schematics manual) of A320 hydraulic system.

Another question if you don't mind: in case of leak in APU fuel feed line in B737, the fuel is drained overboard through shroud and drain mast.
How the fuel in A320 is drained in case of leak in APU fuel feed line ?

Feedback appreciated.

LEVEL600

2nd Feb 2015, 19:45

Hi AeroTech,
There is not big differencies btwn. 737 and 320 design and principles in mentioned qestions. Engine driven pump is cooled by case drain hydraulic flow on both, but 320 do not use fuel tanks collers (heat exchangers).Hydraulic tubing is long enough to serve as cooler during normal operation. This make 320 more sensitive to posible system trip due to fluid overtemperature, which can develop quickly due to internal leak or blockage in suction line. Remeber one case , when hose ruptured on normal system pressure in less than two minutes due to overheated fluid.

APU shroud in pressure cabin is dained to drain mast located in centre of belly fairing behind main landing gear compartement, leak monitor valve(which is normal fuel tank drain valve) is located near for leak check.