jgore
Posts: 518
Joined: Sun Feb 17, 2002 2:41 am

How Do The Papi Lights Work?

Sat Feb 23, 2002 1:08 pm

I'm just wondering how the PAPI lights work.
how they identify an aircraft and thus to give them the proper light information ? do any one know about it ?
thanks.

jgore  Smile/happy/getting dizzy
 
flyf15
Posts: 6633
Joined: Tue May 18, 1999 11:10 am

RE: How Do The Papi Lights Work?

Sat Feb 23, 2002 1:28 pm

Much more simple than that.

Each "station"/"light emitter" has a light in a box. There is a metal divider placed in the box that is precisely aligned with what the glideslope should be at that position. Below this metal divider is a red lens. Due to this, if you are above the angle of the metal divider, you see the white light, if you are below it, you see the red light.
 
jgore
Posts: 518
Joined: Sun Feb 17, 2002 2:41 am

RE: How Do The Papi Lights Work?

Sat Feb 23, 2002 1:38 pm

oooooooo i see,. thanks
 
Av8trxx
Posts: 632
Joined: Sun Nov 11, 2001 7:08 am

RE: How Do The Papi Lights Work?

Sat Feb 23, 2002 1:41 pm

Yes, the PAPI itself does not "identify an aircraft and thus to give them the proper light information", but rather the pilot identifies their position on the glideslope by the colors visible on the PAPI. Perhaps these diagrams & explainations will help:
http://www.bayareapilot.com/vasiPAPI.htm
 
jgore
Posts: 518
Joined: Sun Feb 17, 2002 2:41 am

RE: How Do The Papi Lights Work?

Sat Feb 23, 2002 1:45 pm

yeah i know it, the pilot has to watch on the papi lights.