Question: airplanes and sight lines

[gardener]

I live just a smidgen to the SE of the Love Field incoming flight path and many a night on my patio, I've been outside and wondered just how far away you could discern the landing lights on an airplane coming toward you.
Anyone have some idea of the approximate distance? I can make them out when they're only a tiny pinpoint of light in the Southern sky but have no clue as to some actual distance (although my first impression is that its many many miles)

Not an earth changing topic but I'm a curious person...
Thanks!
Steve W

[ShaneKislack]

Don't know that...but on a clear day I can make out Downtown from Denton.

[StevenGWebb]

I live about 45 miles north of Denton. I can see the landing lights of planes in DFW's approach pattern. Sometimes the pairs of lights will be three deep. The light beams are fairly narrow and can only be seen while the aircraft are pretty head-on to us.

Yes, you can see the lights from a very long distance away.

Steve

[iCe]

I used to watch the lights rise off of DIA from Greeley. Not the new airport. The old one. That was at least 60 miles. Of course the seeing in Colorado used to be really good. I can remember the ATIS at GXY saying "Visibility 100 miles" if the air was exceptional. Not so much anymore. Too many people and too much trash in the air...

[Ahh!]

Curvature of the earth and all that, potentially 200 miles. I read somewhere googling that it was about 220 to the horizon from a plane at 30k or 40k feet. And those lights, if coming at you, are pretty bright. Up here on a Friday night, we can see them stacked 3 to 5 deep coming in from the Texarkana area...

[dminton]

When I used to work on the ramp at IAH, one time I was standing in front of one of the landing lights as the pilot was doing his preflight and turned them on. One of my arms was right in front of the light on the nose gear and it was like someone turned on a blowtorch behind me.

[Cornbread]

The distance will vary depending on when the planes make their turn for final approach. At large airports, this can be anywhere towards 40-50 miles out.

[CaptainG]

Most pilots turn on their landing lights when they descend through 18,000. That is because there is uncontrolled VFR visual traffic below that altitude. Due to the landing approach corridors around Love and DFW, the airplanes usually turn final and line up with the runway about 10-12 miles out at an altitude of about 3-4000 feet. These are the distances you are probably seeing at Love.

At some airports like LAX, most of the airplanes land straight in to the airport and it is common to see them from the time they turn their lights on at 18,000. That would put them just about 55 miles out. Often you can see 15 or more planes lined up for each of the parallel runways.