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View Full Version : Taxiing A320 on snow - spurious ECAMs from Rad Alt


nnc0
4th Nov 2008, 03:06
FCOM 2.04.10 P12 states something to the effect of -
"...During taxi on surfaces contaminated with snow the radio altimeters may not compute any data which results in 'DUAL ENG FAILURE', 'ANTI ICE CAPT TAT FAULT', 'ANTI-ICE F/O TAT FAULT: 'LG SHOCK ABSORBER FAULT' ECAM warnings that may be triggered. These ECAMs may be disregarded...."

Theses spurious ECAMs pop up 2-3 times a yr in a midsized fleet but for an individual crew member they're a rare occurrence. So rare in fact that if it happens, there's little hope they'll remember a few obscure FCOM comments on the issue so everything stops to deal with ECAMs.

Even if they did remember the obscure comment, who in their right mind would simply (Airbus words) disregard them?

A call to Maint just proves the problem is as obscure to them as it is to crew.

I suppose it's easy enough to publish a little reminder on the anomaly but even so how can they simply be disregarded.

Anybody have any insight here?

Any suggestions on how to deal with the problem when they do pop up?
eg In the absence of indications to the contrary (Engs still running) just clear them and use RCL to check for latched msgs then do an FWC reset?

TO MEMO
4th Nov 2008, 08:56
Resets to the FWC would do nothing. The problem comes from the readio altimeter data. I`ve seen this once but can`t remember wich warning it gave. You will notice it`s spurrious because ECAM warning will appear and disapear in seconds and Radio altitude data will be constantly changing in your PFD, has usually happens with wet taxyways and ramps. Disregard those warning until you`re on the runway. Runways are always clean and radio altimeter will then give valid data. By then all warnings will disapear. If not... well in that case I would treat it has a serious warning.

compressor stall
4th Nov 2008, 09:14
Check out the warning #4 on the following approach plate.

http://www.airservices.gov.au/publications/pending/dap/WKSGN01-115.pdf

CS

Swedish Steve
4th Nov 2008, 11:32
then do an FWC reset?
The FWC have big capacitors in them which need to be discharged to accomplish a reset. The quoted time for this is SEVEN MINUTES.
Just cycling the FWC cbs will do nothing, you will not erase the FWC memory.

nnc0
5th Nov 2008, 13:29
Thanks folks - some good info here

Swede
Could you clarify that. Wouldn't you clear a latched AVNS SMK or CARGO SMK on the ground after the fact. Wouldn't you clear them by doing a FWC reset ie dumping the memory?