European Airbus drivers - Dome Light for Night Takeoff?
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Joined: Jan 2022
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From: Miami
European Airbus drivers - Dome Light for Night Takeoff?
I am hearing some scuttlebutt that "in Europe" every night takeoff is done with the cockpit dome light in "Dim" (low) position. The theory is in the event of a catastrophic complete electrical power loss (except for the battery), the switch in low will result in the dome light remaining on, as it is on the Hot Batt bus.
So, what you you guys doing in Europe? You guys built the plane so I am always interested to hear what you folks are doing.
Thank you
So, what you you guys doing in Europe? You guys built the plane so I am always interested to hear what you folks are doing.
Thank you
Only half a speed-brake

Joined: Apr 2003
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From: Commuting not home
There were two reasons for this, historically.
i) The old STBY ATT IND (mechanical) backlight was not available after a failure. In the days prior to ISIS, the dome LT in DIM was a requirement to assure readout.
ii) - not entirely sure on this one - before an essential modification, certain cascading failure could leave the cockpit completely black save for 1 single announciator on OVHD ELEC (bus tie). Pressing this very pb would rectify the situation to a workable state, yet Airbus mandated DIM because completely dark was too awkward, not to mention being unable to find that saviour button in case its internal source had been fried.
These days, I am not aware of any requirement to enforce it. My best informed guess.
i) The old STBY ATT IND (mechanical) backlight was not available after a failure. In the days prior to ISIS, the dome LT in DIM was a requirement to assure readout.
ii) - not entirely sure on this one - before an essential modification, certain cascading failure could leave the cockpit completely black save for 1 single announciator on OVHD ELEC (bus tie). Pressing this very pb would rectify the situation to a workable state, yet Airbus mandated DIM because completely dark was too awkward, not to mention being unable to find that saviour button in case its internal source had been fried.
These days, I am not aware of any requirement to enforce it. My best informed guess.
Only half a speed-brake

Joined: Apr 2003
Posts: 4,459
Likes: 136
From: Commuting not home
Search for BA incident, I only got 2 near misses:
Serious incident Airbus A320-232 N462UA, (aviation-safety.net)
Airbus faces demands for A320 series electrical systems improvement following EasyJet report | News | Flight Global
Serious incident Airbus A320-232 N462UA, (aviation-safety.net)
Airbus faces demands for A320 series electrical systems improvement following EasyJet report | News | Flight Global
Joined: Apr 2022
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From: France
Even with the aforementionned problem, it's always a compromise between two options.
The risk here is something rather serious but has an extremely low probability of occurrence.
The downside with having the dome light on (even dim) is having reduced crew night vision. So a much smaller risk, but every time.
How many times did the complete lighting failure occur, among how many flights ?
I would have assessed that before asking anything about dome light on.
Never heard of dome light on takeoff at my operator (up to 150 320s were used)
The risk here is something rather serious but has an extremely low probability of occurrence.
The downside with having the dome light on (even dim) is having reduced crew night vision. So a much smaller risk, but every time.
How many times did the complete lighting failure occur, among how many flights ?
I would have assessed that before asking anything about dome light on.
Never heard of dome light on takeoff at my operator (up to 150 320s were used)
Only half a speed-brake

Joined: Apr 2003
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From: Commuting not home
Joined: May 2009
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From: somewhere in the middle
The other consideration is when in the latter stages of the Emer Evac Cxlist ("All fire PB... Push), the dome light or a torch becomes your only source of light to read & complete the checklist. I've seen it missed in the sim & made life harder at a critical time.

Joined: Jun 2002
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From: _
From FCTM, EMERGENCY EVACUATION procedure:
On ground with engines stopped, the right dome light automatically illuminates whatever the
position of the DOME light sw. This allows to have the necessary cockpit lighting to complete the
EMER EVAC procedure.
On ground with engines stopped, the right dome light automatically illuminates whatever the
position of the DOME light sw. This allows to have the necessary cockpit lighting to complete the
EMER EVAC procedure.

Joined: Jul 2006
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From: Somewhere over the rainbow
Interesting. Is that from A350 FCTM? Cause on the A320 you must turn it on manually.

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From: Correr es mi destino por no llevar papel





