Blinking versus solid landing lights

[Chris_F]

This past holiday break while on a Southwest flight from BWI to MHT I was reminded of a question I've had for some time and have but haven't asked.

[beaky]

This past holiday break while on a Southwest flight from BWI to MHT I was reminded of a question I've had for some time and have but haven't asked.  When we came in to land I noticed that the landing lights (from what I could see inside the passenger compartment reflecting off the clouds) were blinking.  I've also  noticed this while watching the planes stacked up over Newark airport.  Some were blinking away, some just showing a solid light.

I know the strobe blinks but these weren't strobes, they were big honkin' flood lights.

Is there any significance to solid versus blinking landing lights?  When would one be used over the other?

Supposedly the human eye is better at noticing movement than small points of light, so I guess for collision avoidance, blinking makes sense. But I guess they must switch to a steady beam at some point: wouldn't want to see the runway with a blinking light...  :P

[Brett_Henderson]

Like most, older Cessnas.. the 177RG I just took to Nashville has both the landing and taxi light just below the spinner (as opposed to out on the wing). If neither are turned on there's a "pulse switch" right next to the cowl flap lever that will make them not only flash, but alternate (looks kinda like a train coming at you). If either are turned on, it overides the pulse so you can get a steady beam... landing or taxiing.

As a rule.. I'll turn on anything that will make me more visible when I'm near entering a pattern... and at night I'll leave the pulse off... 'cause it messes up your perception.. especially in marginal visibility.

[Nexus]

Yeah I've read about SWA's pulsing landing lights. I think that one of the purposes of them are to scare away birds...preventing birds strikes.

If it works? I donnu...  ;D
Maybe Silver1SWA can answer this since he works for 'em  :)

[cdn_beaver]

It is also to my understanding that the blinking extends the bulbs life.  

[SilverFox441]

Pulsing, and the increased thermal cycles, will drastically shorten bulf life.

[Ivan]

Xenon tubes... keeping the thing running 100% all the time is more hard on the electrics than letting it slowly charge and discharge.
It's the difference between keeping up some 10KV continuous and just charging it up for a short burst like your photocamera flash.
These lamps are tweaked for a 'slow glow' type of operation, where the gas keeps illumination for a longer time than usual

[Nexus]

I spoke to my 737 flying friend and he heard that his airline has gotten offers of installing them.
Apparantly they kind of works as a dimmer, so they do not BLINK (like you turn the light On and Off).
He also said that those bulbs lasts more than twice (even more) as long than regular landing lights.