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FLX/MCT
3rd May 2008, 17:28
Hey,

i think that i have read some information about the 320's landing lights, but i am not really sure - Do they only extend when the L/G is down or come they down in every situation. Especially when many airlines want these lights to be extended <10,000ft; So i assume that they will work with the gear retracted .
Is there any extension logic at all - for example a speed limit or are they solid enoug to be operated in every situation:confused:


best regards
lukas

AKAAB
3rd May 2008, 17:39
No logic involved. Landing lights are extended and retracted by direct pilot action and there is no relationship with the gear. We call them Cuban Speedbrakes...

Don Coyote
3rd May 2008, 17:41
The landing lights, which extend from under the wings, may be used at any time and there is no speed restriction, although you can feel a slight rumble in the cabin when they are extended above 250 knots.

The taxi and turn off lights, which are attached to the nose gear, are off regardless of switch position when the gear is retracted.

FLX/MCT
3rd May 2008, 17:53
Thank you very much for the quick answer Don Coyote and AKAAB. I thought that it had something to do with the gear but :ugh:.

We call them Cuban Speedbrakes...
:O In Austria we would call that Russian technique.;) I'm not shure if this is mere chance...

smashin'
3rd May 2008, 18:34
Don Coyote was spot in in his/her answer and think we have all joked about being glad of the extra drag when a bit "hot" in the descent. You might be thinking about the nose and turn off lights which are connected to the nose wheel. Surprisingly there are 2 manual switches in the cockpit for these rather than automatically illuminating/switching off with gear extension. Normal SOP is to switch off when gear lever selected up and switched on when gear lever selected down.

PA38-Pilot
3rd May 2008, 19:01
Normal SOP is to switch off when gear lever selected up and switched on when gear lever selected down.Airbus SOP's are to turn the nose lights off with gear retraction, and on with flaps full.

Dan Winterland
4th May 2008, 02:45
Perhaps in your company. Ours go on and off with gear retraction.

PA38-Pilot
4th May 2008, 02:49
Perhaps in your company. Ours go on and off with gear retraction.Probably because your company changed the default airbus SOP's? (which, btw, makes more sense)

AKAAB
4th May 2008, 05:30
We did that under protest for a while, but it was finally decided that flipping switches off on the nosegear lights, that were automatically extinguished on retraction, was a distraction from monitoring the climb performance during a critical phase of flight. Now, we clean up the switches climbing out of 10,000 feet.

Insh Allah
4th May 2008, 13:11
Just a thought guys, it has been 10 years since i'd flown the 320, had an MEL item once. that one of the landing lights was U/S and EXTENDED, MEL stated 1% additional fuel burn, something along those lines :rolleyes:

Sorry, my memory is diminishing rather rapidly... what were we talking about? :ugh:

Swedish Steve
5th May 2008, 22:03
Just a thought guys, it has been 10 years since i'd flown the 320, had an MEL item once. that one of the landing lights was U/S and EXTENDED, MEL stated 1% additional fuel burn, something along those lines

Sorry, my memory is diminishing rather rapidly... what were we talking about?

The two landing lights in the wings are controlled by a three position switch. Retract, Extend and ON. They are retracted by an electric motor. If this motor fails extended they will still work, but the u/s one will be out all the time which causes drag in the cruise.

guiones
6th May 2008, 02:53
AKAAB:

If the proximity sensors fail on gear retraction, I would not like to have a high intensitity (take-off) light on in an enclosed nose wheel well creating heat. That is the reason for the Airbus procedure!

G

Tail-take-off
9th May 2008, 10:58
glad of the extra drag when a bit "hot" in the descent

If you are that desperate remeber to switch the on as well - remember Newtons third law "Every action has an equal & oppsite reaction."

Projecting all those photons forwards will help loads:ok: