Landing lights
Why are you told to raise the blinds as aeroplanes come in to land? And why do they switch the lights off?

I once asked an air stewardess this, and she didn't know; her best guess was that it meant that your eyes would adjust to the light at the destination. I rejected this account on the grounds that it was palpably nonsense.

But I remain perplexed.
( Enzyme is powered by sunlight, Wed 19 Oct 2011, 15:31, 22 replies)

I left the landing lights on once.
Bloody 737 touched down on the stairs.
( scarpe We Stole Bikes, Wed 19 Oct 2011, 15:32, closed)

I think I was told
that it is so if you crash, the people outside can see in to help find you.

probably bollocks
(LetsGetDownToIt, Wed 19 Oct 2011, 15:33, closed)

That's what I heard
fire crews can shine lights in through the open windows to locate survivros/injured
( emvee cruor deo cruoris, Wed 19 Oct 2011, 15:36, closed)

I think it's true.
Also it helps you remain orientated if you crash because you have a visual point of reference. Although I'm fairly sure if I was hanging upside down by a waist fitted seatbelt with my book on the ceiling above my head, I'd know that I was hanging upside down by a waist fitted seatbelt wuth my book on the ceiling above my head.
( scarpe We Stole Bikes, Wed 19 Oct 2011, 15:38, closed)

I call bollocks.
Not least because, if they're that close, they'd be in the fuselage, and so could see you anyway. Besides: you'd expect that to be a reason to keep the lights on.

EDIT: OK, having read emvee's reply, there might be something to it... though it doesn't seem like all that compelling a reason to me. Why worry about shining a light through the window (and from what distance is anyone's guess) when the perspex is reflective, and when, if the lights still work, that'd be better? (If they don't work, there's no point turning them off before landing...)
( Enzyme is powered by sunlight, Wed 19 Oct 2011, 15:38, closed)

The reasons (as far as I know)
They dim the lights so that the pilots don't get any backscatter from the ground which might interfere with the delicate task of not smashing hundreds of people into tiny pieces.
The blinds thing is so that in case they do fail at the primary task, and the plane is less than functional, any light from outside, be it sunlight or searchlight, or even flames from the fuel tanks, will light up the inside to allow better vision for the people trying to escape.
But then I may also be wrong...
(badgerlikespeed, Wed 19 Oct 2011, 15:38, closed)

Compared to the landing lights,
is backscatter all that much of a problem? (I ask that in earnest: I wouldn't have thought so intuitively, but may be wrong.)

The blinds thing, as with the explanations ^up there^, may have something to it, though it seems (again, intuitively) a bit tenuous...
( Enzyme is powered by sunlight, Wed 19 Oct 2011, 15:42, closed)

Perhaps not under normal conditions
If it's foggy/raining hard/snowing then it might have a greater effect. Remember how hard it is not to be distracted when driving in the snow?
( MatJ LOOK, Wed 19 Oct 2011, 17:30, closed)

In light aircraft at least, you're meant to turn stuff like strobes off in cloudy/misty weather, so that you don't have the whole sky as far as you can see blinking at you.
(gordonjcp, Wed 19 Oct 2011, 17:40, closed)

so that we all die cold and alone in the dark

(Quintno EXPERIMENT RUINED CANCELLED, LEFT 4EVER, Wed 19 Oct 2011, 15:50, closed)

The stewardess is right - sort of.
It is to allow the eyes to adjust to the destination in case there's an accident. By having the blinds open and the lights off your night vision adjusts to the ambient conditions at the airport. If there's a crash and you need to get out you're not half-blind when you leave the aircraft as your eyes have adjusted to external conditions. (Eyes take about 10 minutes to adjust to dark conditions.)

That's the theory anyway.
(azgiles, Wed 19 Oct 2011, 15:57, closed)

On that basis,
people would be basically blind every time they left the house after dark. But they aren't. Your eyes may take a while to adjust fully, but they adjust enough pretty darned quickly...
( Enzyme is powered by sunlight, Wed 19 Oct 2011, 16:23, closed)

You do know that the need for it to be done and the reason why it is done aren't the same thing though don't you?
You can dispute that it is necessary as much as you want, but that might not mean that it's not the reason it's done anyway.
( scarpe We Stole Bikes, Wed 19 Oct 2011, 16:26, closed)

This is true.
Reasons that are not reasons to.

But, still: people presumably spent time and energy passing the regulation when they could have been drinking tea, or in the park, or sleeping, so - assuming the rule isn't utterly arbitrary - there ought to be a decent reason to...
:)
( Enzyme is powered by sunlight, Wed 19 Oct 2011, 16:28, closed)

I do think the other bits about orientation and being able to shine flashlights in are probably at play too.

( scarpe We Stole Bikes, Wed 19 Oct 2011, 16:32, closed)

ok guys, I give in
I'll pay for you both to get laid, it looks like you need it
(Quintno EXPERIMENT RUINED CANCELLED, LEFT 4EVER, Wed 19 Oct 2011, 16:35, closed)

Best answer yet.
( The Resident Loon Not a demographic. Do not measure., Wed 19 Oct 2011, 17:21, closed)

What about me?
I'm feeling left out now.
(azgiles, Wed 19 Oct 2011, 17:22, closed)

Anorak mode on!
It takes about ten minutes to fully adjust to darkness (twenty minutes if from full sunlight), within three to four minutes you're eyes have gained about 80%(ish) of full night vision.

In a plane crash the first thirty seconds to one minute are supposedly critical (getting your belt off etc.) so having your eyes at least partially adjusted is supposed to maximise survival rates.

Next time you go out into a dark street (no street lights) pause and see how long it actually takes before your eyes start to see what's there and not what you think is there.
(azgiles, Wed 19 Oct 2011, 17:21, closed)

*notes*

( Enzyme is powered by sunlight, Wed 19 Oct 2011, 20:31, closed)

you raise the blinds to let lighr in and turn off the lights to save power. planes run on batteries and they have just enough AAs on board to make the destination. If they didnt do this flying would be too expensive
( enoughblueskyforsailorstrousers, Wed 19 Oct 2011, 20:55, closed)

I always thought it might be a throwback to the days when the cabin door wasn't as secure as they are now. So if it popped open during landing at night the pilots wouldn't suddenly be faced with glaring reflections right when they *really* need to see where they're going.
(Zedsquared, Thu 20 Oct 2011, 11:35, closed)