A320 Use of Dome light

[FMS_747]

Hi everybody,

I would like to have your opinion, feedback, regarding the use of dome light at night on A320 ? It appears that, on older FCOM, it was recommended to keep it on DIM position by night (Reason ? Case of Elec Emer Config ?) whereas I just can't find anything about it in our current FCOM version. It also appears that some aircraft have been affected by an (old?) OEB requiring the crew to keep the dome light on every time even during daylight due to electrical failures.

Do you know what are the exact current recommendations by Airbus' SOP ?

Thanks a lot.

[Amadis of Gaul]

Of all the things to ask for feedback on, how did the dome light end up at the top of your list?

[compressor stall]

Dome light DIM for t/o in case of RTO

The FCOM is /was ambiguous for landing,but AB have said no requirement for crz or landing. I prefer cockpit as dark as possible at black hole airports.

[No Fly Zone]

Your do know a little bit about night vision, right? If not, please research the subject just a bit.
Most pilots tend to keep light levels low in darkness for reasons that you will learn. During daylight, obviously displays and ambient light are higher. Do some homework and you'll get it. As far as I know, most pilots prefer dim interior lighting at night, giving them a better opportunity to spot intruders in their airspace. Please, read about visual acuity, night vision, rods and cones - and age-based vision changes. If you are over - even 35, some of it will compute.
A few will always dispute this kind of response, "I can see just fine." Next time they sit for a vision exam, they may have a surprise. Wearing lenses - or having them available is not a sin; If you need them, use them! And yes, keep the interior light as low as possible as night.

[Airbrake]

No Fly Zone,

You appear to be missing the point here. Airbus require the Dome light to be on the Dim Setting for a Take off because should you do an RTO the cockpit can be plunged into complete darkness if the dome light is not already selected to "Dim" as you progress through the checklist.

Most pilots switch it off very shortly after T/O when the gear is travelling, for all the reasons you state.

[Fluke]

Perhaps consult your FCTM, should be some suggestions re lightning, low vis ops, evacuation ect.

[Bus Driver Man]

It appears that, on older FCOM, it was recommended to keep it on DIM position by night (Reason ? Case of Elec Emer Config ?) whereas I just can't find anything about it in our current FCOM version.

I'm not flying the A320 anymore, so my FCOM is outdated (18 DEC '12), but this was written at Preliminary Cockpit Preparation:

COCKPIT LIGHTS...................................................... ....................................................AS RQRD
DOME light should be on because it is the only lighting source in the EMER ELEC configuration. The DIM position is recommended for takeoff.

Note the "should" and "recommended". (Not "must" or "has to be")

There used to be an OEB for A320s with an analogue standby attitude indicator that stated that the dome light had to be on DIM at night.
This was because the standby attitude indicator wasn't illuminated in case of Elec Emer Config.
However, this OEB was cancelled after an electrical wiring update which kept the standby attitude indicator light on during an Elec Emer Config.

[compressor stall]

DOME light should be on because it is the only lighting source in the EMER ELEC configuration. The DIM position is recommended for takeoff.


It seems that note disappeared from the FCOM in the last half of 2012.

[flyingchanges]

Dome light DIM for t/o in case of RTO

Just run the APU until after takeoff if you are that worried about it...

[parabellum]

The USAF did a complete survey on things such as, cockpit lighting, meals before and during flights, rest periods before and during flights etc.


The published result regarding night flying was that, in the cruise, the cockpit should be as light as possible as this can reduce fatigue by as much as 75%.


At night, unless you are actually focused on an object then your eyes focused range is about 9 inches, 22.8cms on the other side of the cockpit glass.


Flying in the cruise, at night, with a darkened cockpit is not recommended.

[mr.brembo]

At night it wiil be better to keep dome light on, as Parabellum said. Especialy when lightning stroke is possible.

[Amadis of Gaul]

In our AOM, turning the dome light on is part of F/O's duties AFTER an RTO, it doesn't state to turn it on for takeoff, only after an RTO.

[Rick777]

I can see how this would confuse a few people. Something that you actually need to use some judgement on. There are a few ways to look at it. You want to keep things fairly dark for takeoff so you can see outside. If you are worried about electrical failure leave the light on low. For cruise especially on long legs it helps alertness to have the lights bright. Around top od descent start making it darker so that for landing you have your night vision back and can see outside better for landing and taxi. That's the way I always did it on the bus.

[737Jock]

Is this seriously a discussion?

[Ollie Onion]

It used to be quite a concern as some of the older MSN's had a fault that meant during a complete electrical failure the dome light would NOT be able to be switched on. Consequently an OEB was issued to say that during the hours of darkness the dome light had to remain on DIM throughout takeoff and landing. As far as I know this has been remedied on all models and you can now do whatever you like.