All GEN Fail on A320?
Thread Starter
Join Date: Jan 2006
Location: EU
Age: 43
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
All GEN Fail on A320?
If all generators on an A320 fail and the A/C is above 100 kt the RAT sould automatically extend, while it is extending which is about 8 seconds the batteries power the emergency generation network.
My question is this: is there any indication that the RAT is powering the emergency network or how do you know that the RAT has taken over the task of powering the network from the batteries?
Kind Regards
Tim
My question is this: is there any indication that the RAT is powering the emergency network or how do you know that the RAT has taken over the task of powering the network from the batteries?
Kind Regards
Tim
Join Date: Jul 2000
Location: Germany
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
Flight On Batteries: All Eng/Apu GENs have failed and the EMER GEN is NOT on line. You only have HOT BAT BUS 1+2, parts of DC ESS BUS via BAT2 (parts are shed) and parts of AC ESS BUS via ST INV and BAT 1. My Reminder: LH ND is OFF!
EMER ELEC: All Eng/APU GENs have failes but the EMER GEN is on line. You now have AC and DC ESS Bus and off course the HOT Busses powered. My Reminder: LH ND is ON as it ist powered by the AC ESS SHED BUS, which is now on again!
Note: The EMER GEN can only be powered by the RAT via the BLUE HYD system.
If the RAt is extended, you get a status reminder 'RAT OUT' on the E/WD. But RAT extended does NOT have to mean the EMER GEN is operating.
OK?
MAX
EMER ELEC: All Eng/APU GENs have failes but the EMER GEN is on line. You now have AC and DC ESS Bus and off course the HOT Busses powered. My Reminder: LH ND is ON as it ist powered by the AC ESS SHED BUS, which is now on again!
Note: The EMER GEN can only be powered by the RAT via the BLUE HYD system.
If the RAt is extended, you get a status reminder 'RAT OUT' on the E/WD. But RAT extended does NOT have to mean the EMER GEN is operating.
OK?
MAX
Last edited by Mäx Reverse; 25th Apr 2007 at 15:00. Reason: fingertrouble
Thread Starter
Join Date: Jan 2006
Location: EU
Age: 43
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
"If the RAt is extended, you get a status reminder 'RAT OUT' on the E/WD. But RAT extended does NOT have to mean the EMER GEN is operating."
As I understand it from FCOM Vol 1 Electrical page 13, the EMER GEN can be powered by either the RAT or BATTERIES.
but you did tell me what I wanted to know by saying this:
"you get a status reminder 'RAT OUT' on the E/WD"
Thank you for your quick reply and good help =)
/Tim
As I understand it from FCOM Vol 1 Electrical page 13, the EMER GEN can be powered by either the RAT or BATTERIES.
but you did tell me what I wanted to know by saying this:
"you get a status reminder 'RAT OUT' on the E/WD"
Thank you for your quick reply and good help =)
/Tim
Join Date: Jul 2000
Location: Germany
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
As I understand it from FCOM Vol 1 Electrical page 13, the EMER GEN can be powered by either the RAT or BATTERIES
Take a look at p.3 There it says: The blue hydraulic circuit drives an emergancy generator that automatically supplies emergency AC power to the aircraft electrical system if all three main genartors fail...
Airbus philosophy is that flight on batteries is only a transient condition, so no way to power the elec system to EMER Level by Batteries.
What are you doing? Transition to A320? If so from which aircraft? Other Manufacturers see 'Battery Power Only' as EMER Level and 'Stanby Generator' as ESS Level, so be cautios to understand AI terminology.
Cheers, MAX
Thread Starter
Join Date: Jan 2006
Location: EU
Age: 43
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
I'm prepearing for my first TR in about 1,5 months so I'm trying to understand all the system prior to attending the TR.
I should have written the EMER GEN NETWORK and not only the EMER GEN...
a note on page 13 Electrical sais the following:
"During RAT extension and emergency generator coupling (about 8 seconds), the batteries power the emergency generation network..." But this is only a temporary transition as far as I can understand.
Also on that page it sais:
"If the RAT stalls or if the aircraft is on the ground with speed below 100 knots, the emergency generator has nothing to drive it. The emergency network transfers automatically to the batteries and the static inverter and the system automatically sheds the AC SHED ESS and DC SHED ESS buses."
Doesnt that mean that when all options are lost to generate power, the aircraft resorts to the final source of power, the batteries?
Have you flown the aircraft a lot?
Kind Regards
Tim
I should have written the EMER GEN NETWORK and not only the EMER GEN...
a note on page 13 Electrical sais the following:
"During RAT extension and emergency generator coupling (about 8 seconds), the batteries power the emergency generation network..." But this is only a temporary transition as far as I can understand.
Also on that page it sais:
"If the RAT stalls or if the aircraft is on the ground with speed below 100 knots, the emergency generator has nothing to drive it. The emergency network transfers automatically to the batteries and the static inverter and the system automatically sheds the AC SHED ESS and DC SHED ESS buses."
Doesnt that mean that when all options are lost to generate power, the aircraft resorts to the final source of power, the batteries?
Have you flown the aircraft a lot?
Kind Regards
Tim
Join Date: Jul 2000
Location: Germany
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
Also on that page it sais:
"If the RAT stalls or if the aircraft is on the ground with speed below 100 knots, the emergency generator has nothing to drive it. The emergency network transfers automatically to the batteries and the static inverter and the system automatically sheds the AC SHED ESS and DC SHED ESS buses."
"If the RAT stalls or if the aircraft is on the ground with speed below 100 knots, the emergency generator has nothing to drive it. The emergency network transfers automatically to the batteries and the static inverter and the system automatically sheds the AC SHED ESS and DC SHED ESS buses."
The main reason for this split into AC/DC ESS BUS and AC/DC ESS SHED BUS is to reduce the load on the batteries, as this condition is by AIs definiton only temporary (if reality knows about that may be another question).
Be aware: The system behaviour during RAT operation varies greatly depending on the age of the aircraft. Older aircraft 'lose' the RAT already below 140 knots (that means the entire final approach is on batteries only - so treat them nicely), while the newer rat stalls only at 100 knots during roll out.
Also on the older aircraft you'll have a CRM-Masterpiece in this case: Do you try to start the APU or not? If it works, you're back in business, if it doesn't, will your batteries last for the approach??!
During your training you will discover some more edges in the design which will leave you wondering who on earth designed and certified that, but that's the way it is. Look at the same feature on the A330/A340 and you'll be surprised...
Im A320 rated for 8 years after flying a nice, little, british 3-Engine-High-Wing for 4 years...
Good Luck, MAX
You may PM me anytime if confusion grows. And remember: It's not a bug, it's a feature
Thread Starter
Join Date: Jan 2006
Location: EU
Age: 43
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
ahaaaaa... now I see =)
Well that APU question is pretty obvious, you don't gamble with the only thing you have left... right? =)
I know a captain at mytravel and he also gave me the heads up on the older A320's running with the 140 kt limit but he also said that they are probably being updated to the 100 kt limit, do you know anything about that?
I could sure any help I can get, your help is much appreciated, thank you =)
Do you by any chanse know anything about the Job market for pilots in Europe and perhaps anything about Sabena Flight Academy? That's where I'm most likley going to do my TR on the 320...
Kind Regards
Tim
Well that APU question is pretty obvious, you don't gamble with the only thing you have left... right? =)
I know a captain at mytravel and he also gave me the heads up on the older A320's running with the 140 kt limit but he also said that they are probably being updated to the 100 kt limit, do you know anything about that?
I could sure any help I can get, your help is much appreciated, thank you =)
Do you by any chanse know anything about the Job market for pilots in Europe and perhaps anything about Sabena Flight Academy? That's where I'm most likley going to do my TR on the 320...
Kind Regards
Tim
Join Date: Apr 2007
Location: saudi arabia
Age: 62
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
a c instructor
you should have many attention getters the first one is your common sense (no offend) second : overhead emergency elec panel lite fault lite will come on if the rat did not deploy
Thread Starter
Join Date: Jan 2006
Location: EU
Age: 43
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
Since I'm pretty new at this aircraft, just started to study it and I hadn't reached the chapter which handles the buttons on the over head panel yet =) so no, I didn't know that button excisted =)
Join Date: Mar 2005
Location: Queenland, Australia
Posts: 176
Likes: 0
Received 0 Likes
on
0 Posts
Hey Founder,
I agree with previous posts.....Having just completed the last sim cycle with dual gen failure
where it took a few seconds to re-establish emer power, you will be a tad busy hand flying with your offsider cancelling the master warning/caution (more than once I tell you! ) before you will realise the RAT has extended! Apart from pre-mentioned S/D "rat extend" Just check the ECAM elec page to see the power configuration.
When you get your FCOM's, the QRH will give you what systems you have remaining in EMER ELEC CONFIG.
Best of luck!
I agree with previous posts.....Having just completed the last sim cycle with dual gen failure
where it took a few seconds to re-establish emer power, you will be a tad busy hand flying with your offsider cancelling the master warning/caution (more than once I tell you! ) before you will realise the RAT has extended! Apart from pre-mentioned S/D "rat extend" Just check the ECAM elec page to see the power configuration.When you get your FCOM's, the QRH will give you what systems you have remaining in EMER ELEC CONFIG.
Best of luck!
Join Date: Mar 2005
Location: Queenland, Australia
Posts: 176
Likes: 0
Received 0 Likes
on
0 Posts
The A320 is certified to have approx 60mins on emergency battery supply.
Trying to start the APU on batteries alone reduces this time ( by approx 3 mins, I think..to be corrected if so, for every attempted start) so you'll want to be within 60 mins of the nearest suitable airport before things go dark.
One sim check involved DC 1+2 FAULT which meant you couldn't start the APU because the batteries were not available-no DC BAT BUS
Trying to start the APU on batteries alone reduces this time ( by approx 3 mins, I think..to be corrected if so, for every attempted start) so you'll want to be within 60 mins of the nearest suitable airport before things go dark.
One sim check involved DC 1+2 FAULT which meant you couldn't start the APU because the batteries were not available-no DC BAT BUS
Join Date: May 2006
Location: out of a suitcase
Posts: 26
Likes: 0
Received 0 Likes
on
0 Posts
Start the APU on bat only?
In the QRH 1.01 Elec Emer Config Sys Remaining it says that the APU ECB-STARTER only is available when the RAT is running. It says INOP when on BAT ONLY in flight en is only restored ON THE GROUND when speed is below 100 knots.
Can you explain me how you can start the APU in flight on BAT ONLY?
In the QRH 1.01 Elec Emer Config Sys Remaining it says that the APU ECB-STARTER only is available when the RAT is running. It says INOP when on BAT ONLY in flight en is only restored ON THE GROUND when speed is below 100 knots.
Can you explain me how you can start the APU in flight on BAT ONLY?
Join Date: Apr 2007
Location: Italy
Posts: 84
Likes: 0
Received 0 Likes
on
0 Posts
re from captain87
As Coffee Black None says,
it's impossible to start the APU on BAT only in flight;
this to preserve the batteries in case of an APU start fault and a RAT stalling at the same time. In this case we will have no generators supplying all the buses. Once the RAT ceases to supply the ESS AC and DC below 100 kts, the battery power takes over until reaching 50 knots ...
Furthermore the APU can be started on batteries only on the ground, since the complete lost of electrical power would be less serious.
The minum battery voltage is 25.5 but the batteries cannot discharge below 22.5 to allow an eventual APU starting.
This has been programmed by Airbus as system logic ...
Kind regards !
it's impossible to start the APU on BAT only in flight;
this to preserve the batteries in case of an APU start fault and a RAT stalling at the same time. In this case we will have no generators supplying all the buses. Once the RAT ceases to supply the ESS AC and DC below 100 kts, the battery power takes over until reaching 50 knots ...
Furthermore the APU can be started on batteries only on the ground, since the complete lost of electrical power would be less serious.
The minum battery voltage is 25.5 but the batteries cannot discharge below 22.5 to allow an eventual APU starting.
This has been programmed by Airbus as system logic ...
Kind regards !
Join Date: Jul 2000
Location: Germany
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
@ aulglarse
In our ships we have two 24V and 23Ah Batteries which are according to me book good for only 30 Minutes of Emergency Power.
Regards, MAX
The A320 is certified to have approx 60mins on emergency battery supply.
Regards, MAX
Join Date: Apr 2007
Location: Italy
Posts: 84
Likes: 0
Received 0 Likes
on
0 Posts
re from captain87
Yes, precisely from 22 to 30 minutes according to the battery load.
It's important to remind that the batteries voltage doesn't drop below 22.5 v, to allow an eventual APU starting attempt.
Regards
It's important to remind that the batteries voltage doesn't drop below 22.5 v, to allow an eventual APU starting attempt.
Regards