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View Full Version : A320F avionics cooling with inop blower or extract fans


tubby linton
9th Sep 2017, 22:09
I would be interested to hear of pilots experience of operating with degraded avionics cooling or system functionality of the AEVC and its components in the A320F
I have always been led to believe that Airbus over engineered this system because they were concerned about the adverse apects of overheating in the avionics bay with 1980s era electronics. I am led to believe that one of the very early A320 ended up with only a single SEC working because of a cooling failure.
CRT would start to lose colours with inadequate cooling but what does an LCD screen do?

Metro man
10th Sep 2017, 01:44
The problem is that when the fan fails it does so with smoke and a burning smell resulting in a diversion.

I've never experienced a cooling problem in the cruise and SOP is extract vent override when parked during heavy rain.

LCD screens often go dark if overheating, I've seen this with car electronics but at that stage the whole interior was like an oven and too uncomfortable to sit in.

Escape Path
10th Sep 2017, 04:42
As Metro man said, the fan failing in flight makes for an interesting scenario, as the fan makes a weird noise (which you can feel through the cockpit floor on the right side) and the moment if fails it produces a smell of smoke.

I've experienced failure of WX radar during taxi out, takeoff and climb, then returning back to normal only to fail again during descent, approximately below 10000ft. It's happened with an AEVC item MEL'd so the radar was failing due to poor ventilation.

Interestingly enough, one time I had a lightning strike and the radar failed immediately afterwards (with AEVC working normally). We thought it was cooked and then it was back to normal within 5 or so minutes of the strike. I assume it was due to a similar overheating and once it got back to temp it started working again

Gary Lager
10th Sep 2017, 12:53
I have had a AEVC fail in cruise - the system stops the blower fan, and air con air is added and exhausted overboard via the mini flap on the outlet valve, so similar (but not identical) to smoke config.

No further issues for the rest of the flight but there is definitely an increase in noise with the intermediate extract valve open at crz alt.

tubby linton
10th Sep 2017, 14:16
Thankyou for the replies. The majority of problems I have read about seem to be with bearing failures in the extract fan.

Consol
10th Sep 2017, 15:45
Had one, noise and smoke. Useful to know it's cb and I believe it is on AC2. It would hopefully pop the cb in time as current draw built up but it is a very uncomfortable place to be until you have it under control.

tubby linton
11th Sep 2017, 11:52
Airbus Testing Health Monitoring For A320 Avionics Fans | MRO Network (http://www.mro-network.com/maintenance-repair-overhaul/airbus-testing-health-monitoring-a320-avionics-fans)