Landing Lights

[paulhn]

Hello,
Would someone be kind enought to explain the rules regarding the use of landing lights. I was under the impression that in the UK the use of landing lights under 10000ft was compulsory, however while watching some arrivals at Heathrow today I saw at least one aircraft turn its lights on while on finals and one land with them turned off.
Thanks for any help.
Paul

[Knold]

One usually turns them on when cleared to land.
There is no use for them before that.

[Thunderbug]

...........except big bright lights in the sky (even in daylight) can make it easier to spot other planes and avoid bumping in to them, and they too can spot you. :ok:

My outfit has a compulsary landing lights on below 10,000', but I'm certain that it is not a regulatory requirement.

T'bug

[Meeb]

<<One usually turns them on when cleared to land.>>
<<There is no use for them before that.>>

That must be one of the most inane statements to be aired on PPRuNe for quite some time... :rolleyes:

[Hand Solo]

AFAIK it's not compulsory to turn them on any time. Lots of people turn them on below FL100 as company SOP purely for visibility purposes, although we tend not to on the A320 as the lights extend into the airflow and cause noticeable vibration. If people turn them on just before landing its usually becuase they've forgotten them and have just realised they can't see the runway too well!

[Thunderbug]

Hand

Thanx for that - you have just solved one of the mysteries of life.

Lurking as I do in W London, I have noticed the Airbuses seem to be doing stealth approaches over the rooftops in complete darkness - And I now know the reason

Cheers :D

T'bug

[Knold]

Well that's what we usually do anyway.

[NigelOnDraft]

<<although we tend not to on the A320 as the lights extend into the airflow and cause noticeable vibration>>
And also another 100fpm descent when you get really hot & high!

NoD

[Pilot Pete]

Just to expand,

Also useful in the descent for spotting those thin whispy clouds on a pitch black night (which may mean you need the engine anti-ice on), and conversely often turned off in the cloud due to the glare caused up front.

I flown for airlines who have varying ideas on lights use. Most SOP their use below 10,000ft. Where they differ is how they are used and by who, in conjunction with the nose wheel taxi light.

The best SOPs that I have flown with rgarding lights was to use them as, or in response to 'triggers'. When cleared to taxi, taxi light on, line up strobes on, take-off landing lights on. In the descent passing 10,000 landing lights on and seatbelts on, when cleared to land taxi light on. Helps when you were cleared to land a long way out and then when passing a couple of mile final getting that moment of doubt.......all you have to do is look up at the switch position. My current airline don't use this method and the lights are the PFs territory and there is a wide variation in how and when they are used. Many captains taxi with no lights on which I personally don't agree with (daytime only of course) and some have the landing lights on too..........

Some say they are saving the bulbs by turning them off, only to have to put them on again a little later, the way I understand it it's the surge on light up that causes more wear to a bulb rather than leaving it on. Anyone know better?

PP

[4PON4PIN]

Almost 24 hrs and nobody has mentioned that below 10,000ft you are more likely to encounter flyers of the feathered variety and hence SOP in many companies is to have inboard landing lights on below 10000ft for T/O & Ldg phase.
And in case anybody is wondering..(DUH!), it is not so you can see the birds it's so the birds.....

It is not recommended to use ldg lights when making an approach below Cat I conditions because of the diffusion of light making visual cues more difficult to acquire.
:cool:

[PaperTiger]

Has it ever been satisfactorily demonstrated that landing lights are a bird deterrent ? One US airline study concluded that they made no difference (same with whirly-painted fans), but that may be just that one airline's experience. Noise is likely to be more of a factor but planes are getting quieter, which may account for the increasing occurrence rate for birdstrikes.

Lights below 10000 does mean that other humans have a better chance of seeing you. Assuming they are looking :oh:

[Rynopilot]

A certain Canadian airline extends the landing lights below 18000'.

[Pilot Pete]

Ryno,

possibly as a 'trigger' for QNH? Is 18000 the transition in Canada, it is in the US?

PP

[Rynopilot]

That is correct, however even flying throughout Europe where the transition is much lower the same procedure applies.

The logo lights are also selected off at this time.

[viking737]

American Airlines SOP is Landing Lights on below 18,000.

[slingsby]

See and be seen

FL100 up or down - landing lights off/on
Strobes off only when clear of active runway or on when entering.
Nose gear lights on - cleared to land/depart (unwritten secondary acknowledgement to Tower ATCo of acceptance of clearance)
Position/anti-col. lights on at all times when in motion

Logo light - optional, helps atc at night but doesn't help if using reverse thrust early mornings, grumpy joe soap public might look out of his room and know who woke him up and know who to complain about...

Landing lights use in-flight for cloud penetration, engine anti ice requirements, can be a wake up call if left on and you enter thick cloud, gets a bit bright in your comfy dark pit.

More power to the thrusters !!!!

[PlaneTruth]

Pilot Pete asked:

"Some say they are saving the bulbs by turning them off, only to have to put them on again a little later, the way I understand it it's the surge on light up that causes more wear to a bulb rather than leaving it on. Anyone know better?"

I believe its on shutdown.

I remember an old study in the 80's which identified the highest likelihood of failure precisely at the point where the energized filiment is powered off. You'll experience it at home sometimes when you turn a light off and you get a blue arc which catches your attention. Sure enough, turning the bulb on agan reveals its toast.

A way to avoid this is by slowly and gradually removing the power. Not avaiable at home, this system is installed on many bizjets and on a few airlines (mine included). It's called the PulseLite system and it pulses the lights by varying the voltage to the filament. (Some motorcycles here in the states have a variant installed for better visibilty.) Tests have revealed a markedly better bulb life using this system. As it keeps the filament temperature lower lessening the likelihood of failure.


PT

[604guy]

Outboard lights on/off through 10,000 per SOP's. Inboard lights on whenever the gear is down whether in flight or on the runway. Taxi light on whenever the aircraft is elsewhere on a manouvering area. Also when conducting a low visibility approach i.e. 3/4 mile or less and at night then the taxi light only is used for approach and landing due to light being refracted back into your face and making it a tad more difficult to pick up the visual cues.

As far as bulb longevity, our maintenance folks have found over the years that it is important to place the bulbs so the filiment is in the vertical position. They have found that by anything other than that position, particularly horizontal, it will reduce the life by half or less.

604guy

[zekeigo]

Airlines SOP requires the use of Runway Turnoff lights ON below 10000 feet, for see and avoid purposes.
The landing lights should be turned on at 500 feet during the night, except for approaches during low visibility procedures.
Zeke:ok: