Lights....

[Mike Southern]

I'm not a pilot, but I do fly a lot and I am perplexed by the regulation for dimming the cabin lights during the hours of darkness....

Is there a good technical reason for this, or is it just one of those things????

[whoop-whoop]

At night the cabin lights must be dimmed for T/O & Landing to enhance your night vision, should it become necessary to evacuate the A/C in the relative darkness of emergency lighting only.

[A Very Civil Pilot]

if it's dimming it during the hours of darkness, it's so that those that want to sleep can. As for t/o & ldg, W-W has a reasonable point.

[Centaurus]

Extract from earlier answers to the reasons Hudson


Member # 9849
posted 14 February 2001 11:06
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In an emergency evacuation, the dimming of cabin lights is a complete waste of time. It is known that one bright light will completely ruin night vision and that 30 minutes is needed for full night adaption. And night adaption is the only reason why traditionally cabin lights are dimmed.
The cabin crew have their night vision already shot to pieces even before the take off starts as they mill around the galley area (plenty of bright lights there) and as they walk down the aisle checking seat belts. That is because many pax leave reading lights on which which are in full view of the cabin crew.

The cockpit crew will have never gained night vision adaption as they taxi due to myriad of airport lights, runway lights and the beams of their own landing lights, let alone the overhead map-reading lights.

At least one major airline to my knowledge realises that dimming of cabin lights is all a big myth and leaves them on for take off and landing. One spin off is that pax wearing glasses can better see exactly where the position of the emergency exits are. It is well known that people who need glasses to see adequately, are invariably handicapped if the ambient light is poor as in a darkened or dimly lit cabin. Pax that take the trouble to read the emergency procedues card located in the seat pocket will often turn on their overhead reading light when the cabin lights are dimmed. Scratch their night adaption. Dimming the lights is significantly counter-productive to the elderly and those who wear spectacles.

Some third world cabin crew even turn off all the cabin lighting in full daylight for take off and landing - then turn it back on in flight! That is because their ops manual says that cabin lights must be turned off for ALL take off and landings. That is a myopic viewpoint for sure.

A similar mentality once existed at Manila airport where all the VASIS lights for runway 24 were showing crazy angles. To a pilot report of contradictory VASIS indications, ATC replied that this was probably the result of a minor earthquake causing damage to the VASIS boxes. But because their ATC Manual stated that the VASIS must be left on for all arrivals, they did just that..

Far better for airlines to leave the cabin lights on full bright for take off and landing, so that pax can note the position of the emergency exits in front and back of them. Anyway, if the aircraft catches fire, the glare of the flames are really going to ruin your day -and your night vision.