British Airways does not use nav lights?

[pete_auau 1,163]

They don't  need  taxi lights  David  because the Captain instructs  the FO   to lean  out the window  with his  High  beam  torch  to  taxi,   although he might  find  this  difficult   on landing  though

[skelsey 765]

I've never heard of BA not having tax lights? This looks like taxi lights to me. Do they just turn on runway turnoff lights instead of taxi lights?

 

Outboard landing lights usually, IIRC.

[Boeing or not going 578]

They don't  need  taxi lights  David  because the Captain instructs  the FO   to lean  out the window  with his  High  beam  torch  to  taxi,   although he might  find  this  difficult   on landing  though

That explains this... http://aviation-safety.net/database/record.php?id=20131222-0

 

-David Lee

[JRBarrett 3,080]

However, even though I don't know how the lights are exactly, I'd find it hard to believe that there was just ONE bulb per nav light. There must be redundacy so as if just one bulb fails, you still got a green functional light.

 

Most larger aircraft do have two lamps per Nav light assembly. In some installations, both lamps are illuminated whenever the Nav light switch is "on", in others, like Embraers, and Airbuses, the two lamps are on two separate circuits - controlled by a switch on a maintenance panel in the cockpit. Only one lamp is "on" at a time. If one burns out, flipping the switch will bring the alternate circuit into play, lighting the backup lamp.

 

Keeping the lamps off in daytime is probably not so much as matter of saving money on lamp replacement - incandescent Nav lamps are not very costly (in aviation terms at least) - but a matter of dispatch reliability. A burned out Nav light is a complete show-stopper if an aircraft is scheduled to fly during hours of darkness. It cannot be dispatched with an inoperative Nav light.

 

Depending on the specific aircraft model, replacing Nav lights may not be a simple or quick process. On the business jets I work on, the aerodynamic fairing that covers the lamps has polysulfide sealant around its entire mating surface, and that is the problem. Replacing the lamps themselves may not take long, but after the fairing is reinstalled, new sealant has to be mixed and applied - and that sealant can take up to 12 hours to cure sufficiently so that the aircraft can be flown. Without the sealant, if the aircraft flies through any precipitation, water can easily get into the inside of the fairing, and if even a small drop touches the hot lamp, it will crack.

 

Many new aircraft have LED Nav lights. Those do have a much longer life than incandescent bulbs, but they do eventually wear out too. Their light output will diminish with age. With LEDs, costs ARE a factor. An incandescent aircraft Nav lamp might cost only $15 or $20 - but a replacement LED light assembly might easily cost upwards of $4000.

[Ralgh 43]

I believe another reason was the sun glare through the "eyebrow" windows. Those windows were more annoying than anything else, pilots were always covering them with charts or newspapers.

 

 

 

Interesting! Do these 737 have a non-functioning LOGO lights switch in the overhead?

No, they didn't install the switches on those planes.

[Alpha Floor 237]

Most larger aircraft do have two lamps per Nav light assembly. In some installations, both lamps are illuminated whenever the Nav light switch is "on", in others, like Embraers, and Airbuses, the two lamps are on two separate circuits - controlled by a switch on a maintenance panel in the cockpit. Only one lamp is "on" at a time. If one burns out, flipping the switch will bring the alternate circuit into play, lighting the backup lamp.

 

Keeping the lamps off in daytime is probably not so much as matter of saving money on lamp replacement - incandescent Nav lamps are not very costly (in aviation terms at least) - but a matter of dispatch reliability. A burned out Nav light is a complete show-stopper if an aircraft is scheduled to fly during hours of darkness. It cannot be dispatched with an inoperative Nav light.

 

Depending on the specific aircraft model, replacing Nav lights may not be a simple or quick process. On the business jets I work on, the aerodynamic fairing that covers the lamps has polysulfide sealant around its entire mating surface, and that is the problem. Replacing the lamps themselves may not take long, but after the fairing is reinstalled, new sealant has to be mixed and applied - and that sealant can take up to 12 hours to cure sufficiently so that the aircraft can be flown. Without the sealant, if the aircraft flies through any precipitation, water can easily get into the inside of the fairing, and if even a small drop touches the hot lamp, it will crack.

 

Many new aircraft have LED Nav lights. Those do have a much longer life than incandescent bulbs, but they do eventually wear out too. Their light output will diminish with age. With LEDs, costs ARE a factor. An incandescent aircraft Nav lamp might cost only $15 or $20 - but a replacement LED light assembly might easily cost upwards of $4000.

 

 

No, they didn't install the switches on those planes.

 

Thanks Tom!

 

And thanks Jim for your elaborate response from a mechanic's point of view, very much appreciated!

[Lairyliam 17]

 

 

As mentioned above, nobody said it was about saving fuel.

 

 

My bad. I misread somebody's post on page one... They were talking about Iberia.

​In a previous life, my job was to save fuel/time for BA (well British Regional/CitiExpress) on a daily basis. We would work on a rough rate of 145gbp a minute, that the plane wasn't sat on the floor, and that was 10 years ago.

​They stripped all the APU's out of the Dash 8's to save money, so I'm not surprised that they are now onto lightbulbs....

​Lets be honest, we could close off lavatory's,  stop using APU's on all aircraft, and even go to the extreme of flying on one engine.... Just because we have two doesn't actually mean you have to use it do you? Trip 7 can be certified for what, 300 mins of flight on one engine. there is a maths equation in there somewhere between drag, weight, increased fuel et al for someone far cleverer than I!

​and yes, its an absurd suggestion...

​Liam "I forgot my name" Reynolds

[Boeing or not going 578]

 

 

 

 

My bad. I misread somebody's post on page one... They were talking about Iberia.

 

​In a previous life, my job was to save fuel/time for BA (well British Regional/CitiExpress) on a daily basis. We would work on a rough rate of 145gbp a minute, that the plane wasn't sat on the floor, and that was 10 years ago.

 

​They stripped all the APU's out of the Dash 8's to save money, so I'm not surprised that they are now onto lightbulbs....

 

​Lets be honest, we could close off lavatory's,  stop using APU's on all aircraft, and even go to the extreme of flying on one engine.... Just because we have two doesn't actually mean you have to use it do you? Trip 7 can be certified for what, 300 mins of flight on one engine. there is a maths equation in there somewhere between drag, weight, increased fuel et al for someone far cleverer than I!

 

​and yes, its an absurd suggestion...

 

​Liam "I forgot my name" Reynolds

 

Some Dash 8 -400 operators and other regionals in America do not have running water/toilet or an apu. - David Lee