AC BUS 1 Failure A320

[jorel]

Hi

Any idea on what sort of ECAM you would expect on a failure of AC bus 1 on the airbus 320. Not sure how it would priortise the loss of AC essential Feed.

Thanks

[pakeha-boy]

jorel.....I carry a list of everything that is on the AC Bus 1.....theres a lot....never seen it ,hope I never have to......

But in the Sim,the give me emergency electrical.....loss of Both AC Bus1 and 2!!!:eek:

IT IS NOT A PRETTY PICTURE.....(thats why I have a QRH)....good luck if you ever lose it.....1 is ok...both of them means more work than you are paid to do...PB

[Dream Land]

Nowadays Emergency Electrical is no big deal, big rat and all. :}

[bus787]

Ac bus fault ecam will tell you to put AC ess Feed on.This will enable AC BUS2 TO SUPPLY AC ESS VIA ESS TR.
hOPE THIS IS CLEAR..REGRDS

[jorel]

Thanks very much for the replies
Was thinking does ECAM first come up with AC BUS 1 fault or AC Ess bus fault. FCOM drill for AC BUS 1 makes no mention of AC ESS FEED....ALTN.
AC ESS FEED...ALTN comes up in the drill for AC ESS BUS Fault.
Was just wondering what the sequence of ECAM would look like and how long it would take to get the ac ess bus powered

[Dream Land]

Watch for yourself. :} http://www.youtube.com/watch?v=-nJ6nRJrKcE

[Mäx Reverse]

Technically it should do the switching automatically but I have seen it where it has not.



No, the A320 unfortunately doesn't have any kind of Auto ESS Bus-Xfer :=

After the Incident with G-EUOB (http://www.aaib.gov.uk/cms_resources/S3-2006%20G-EUOB.pdf) my company added a note in the book, saying that in the event of a major ELEC faiure where the AC ESS FEED Fault Light ON, the crew MAY decide to select alternate ESS FEED outside procedural guidance in order to quickly improve the overall electrical status and to regain COMs.

Regards, MAX reverse

[Rod Eddington]

This may be of interest to you:


http://www.aaib.gov.uk/publications/special_bulletins/s9_2006_airbus_a319_111__g_ezac.cfm

[jorel]

Thanks very much very useful...

Leading on from the G-EUOB incident where the EC ESS feed worked..

in the incident with G-EZAC where AC ESS feed did not work and could not be put on line, would any one of considered manually selecting EMER Elec and then reconfiguring to maintain alternate law on landing.

Apologies if this has been covered elsewhere

[jorel]

thinking about it I am not sure you can revert back to alternate law once you have selected EMER ELEC, even if you turn the GEN or GENS back on before gear down as in the case of smoke.......... Anyone have any ideas

[Mäx Reverse]

Just to be clear, even with an AC Bus 1 Fault and the AC ESS FEED not yet selected to ALTN you don't have an EMER ELEC condition.

If you do have one, you've got 5 Minutes until ADIRU 2 and 3 will lose power. If you can restore any one GEN withtin that 5 Mins you're fine, otherwise it will be a Direct Law Landing.


thinking about it I am not sure you can revert back to alternate law once you have selected EMER ELEC


In EMER ELEC you are in ALTN LAW until Gear Down, so you woult 'revert back' to NORM LAW if power is restored.

Regards, MAX reverse

[RvB]

Is there anything to consider when selecting AC ESS FEED to ALTN outside procedural guidance - anything that caused AI not to have installed an Auto Xfer for that bus ?

Thanks RvB

[Dream Land]

Read the link in post #9.

[Mäx Reverse]

I wouldn't rule out the possibility that just pushing the ESS AC FEED P/B without having the least bit of an overview over the aircraft status or without any idea of the electrical prolem's nature might tur bad to worse. But the probability is obviously small enough, otherwise the 'note' wouldn't have found it's way in the books.

In my opinion the A320 systems' design is finally starting to uncover some dark spots, same thing with the PTU in case of an G or Y HYD low level.

There were some cases, where this happened during T/O Roll or shortly thereafter. During the time it took to climb to 1500 AGL (end of TO Inhibition) and until the crew had handled the ECAM-Procedure which would finally call for PTU.....OFF, the PTU overheated and caused the other HYD System to fail due to a RSVR OVHT condition, thus causing a G+Y HYD Failure and thereby a full-blown Emergency.

So now we have another 'note' to switch off the PTU by memory in this case, kind of ridiculing the entire ECAM handling. I see it's important, but why not create a '1st class memory action'? Unfortunately a modification is not to be expected, seems like AI is rather tending to NWS Control Boxes and the like. :ugh:

What's next?

Regards MAX