rw lights

Here's the answer for just a couple of your questions.....

VASI System
Most runways with a published IFR approach are equipped with lights that help pilots determine if they're on the proper descent path during the final stages of approach and landing. The most common system is the VASI, or Visual Approach Slope Indicator.

VASIs come in several varieties, but a typical system includes two sets of light bars placed on the left side of the runway, one nearer the landing threshold than the other. Lenses split the light into red and white beams.

Three combinations of lights exist with this arrangement. If you're approaching the runway on the proper glide path, usually a three-degree slope, you'll see a red light above a white light.

Left, "Red over red, you're dead," approach is low. Center, "Red over white, you're all right," approach is perfect. Right, "White over white, you'll fly all night," approach is high.

Intuitively, of course, one understands that red-red is "danger," or low, and then the others take care of themselves.

PAPI: VASI, but a notch better
PAPI, the Precision Approach Path Indicator, as its name implies, vertically guides you to the runway with a narrower beam of light, thus more precisely.
The familiar red and white lights have the same meaning as with the VASI, but the PAPI places them side-by-side rather than front-to-back.
Since the PAPI systems uses a narrower beam of light you must fly the glide path more precisely than the VASI to stay on the beam. You really have to stay on your toes when flying the VASI because there is no indication that you are drifting off the glide path until the lights switch to red-red or white-white. You may find yourself flying an S-slope down to the runway: bump the white-white, descend and bump the red-red, climb and bump the white-white, etc.

The PAPI, with its extra lights, forewarns you when you are drifting from the desired glide path. If you see three reds or three whites, slightly off the glide path, it's time to take the necessary action to stop the drift. Minor power adjustments should do it and knowing the correct RPM for the desired rate of descent puts you a jump ahead of the game, where the lights are determined that you shan't stay between them. It's actually rather fun. You feel as if you've beaten the system when you slide all the way down the glide path with the PAPI lights properly remaining white-white-red-red.

Source: http://www.navfltsm.addr.com/index.htm

ALS-- generic term for all "approach lighting systems'

REIL-- "runway end identifier lights"-- two strobe lights at the corners of the approach end of the paved runway-- the runway may or may not also have a row of green lights along the approach end of the runway.

TDZ-- "touch down zone" lights

HIALS-- "high intensity approach lighting system"-- white lights along the edges of the paved runway.

MALSR-- "medium intensity approach lighting system" (don't know what the R stands for) -- white lights along the edges of the runway, only not as bright as the HIALS lights.

ALSF 1 -- approach lighting system with sequenced flashing strobe lights (rolling ball of light) for a "CAT 1" ILS approach. These lights are out in the "boonies" in advance of the paved runway.

ALSF 2 -- different arrangement of lights from the ALSF 1 -- this one is designed for a "CAT 2" ILS approach. 😎

I apologize for leading you astray on the MALSR lights and not addressing the RAIL at all. Here is some more info.

RAIL-- "runway alignment indicator lights"

MALSR-- "Medium Intensity Approach Lighting System with RAIL"-- these lights are in advance of the runway, and contain a "rolling ball" of light as in the ALSF 1 and ALSF 2 systems.

HIRL, MIRL, and LIRL-- These are the white lights along both sides of the paved runway-- high intensity runway lights, medium intensity runway lights, and low intensity runway lights.

TDZL-- "touch down zone lights"-- this is a row of white lights on both sides of the runway centerline. They begin 100 feet inside the threshold and extend to 3,000 feet past the threshold. 🙄

very good sr
TNAKS! 😀