PAPI
http://icl.cs.utk.edu/papi/

http://icl.cs.utk.edu/projects/papi/overview/

Here is me in the Baron with the PAPI lights on approach!




VASI
http://www.flytandem.com/vasi/vasi.htm

http://www.academy.jccbi.gov/cgi/course.cgi?cn=44118

http://www.thaiflyingclub.com/linkrunway05vasi.html

http://www.mail-archive.com/flightgear-devel@flightgear.org/msg19780.html

http://www.mail-archive.com/flightgear-devel@flightgear.org/msg19773.html

Hope this helps Ken!

Dave  

Precision Approach Path Indicator PAPI

A precision approach path indicator (PAPI) system shall be provided to serve the approach to a runway whether or not the runway is served by other visual approach aids or by non-visual aids, where one or more of the following conditions exist:

1. The runway is used by jet aircraft or other aircraft with similar approach guidance requirements;

2. The pilot of any type of aircraft who may have difficulty in judging the approach due to:

     A: Inadequate visual guidance which may be experienced during an approach over water or featureless terrain by day or in the absence of sufficient extraneous lights in the approach area by night, or

     B: Misleading information which may be produced by deceptive surrounding terrain or runway slopes.

3.  The presence of obstructions in the approach area may involve serious hazard if an aircraft descends below the normal approach path, particularly if there are no non-visual or other visual aids to give warning of such objects;

4.  Physical conditions at either end of the runway present a serious hazard in the event of an aircraft under-shooting or overrunning the runway; and

5.  Terrain or prevalent meteorological conditions are such that the aircraft may be subjected to unusual turbulence during approach.


Description:
The PAPI system shall consist of a wing bar of 4 sharp transition multi-lamp or paired units equally spaced. The system shall be located on the left side of the runway unless it is physically impracticable to do so.

Note:- Where a runway is used by aircraft requiring visual roll guidance which is not provided by other external means, then a second wing bar may be provided on the opposite side of the runway.

Wing bar shall be constructed and arranged in such a manner that a pilot making an approach will:-

when on or close to the approach slope, see the two units nearest the runway as red and the two units farthest from the runway as white or,

when above the approach slope, see the one unit nearest the runway as red and the three units farthest from the runway as white and when further above the approach slope, see all the units as white or,

when below the approach slope, see the three units nearest the runway as red and the unit farthest from the runway as white and when further below the approach slope, see all the units as red.




The approach slope as defined in Fig above shall be appropriate for use by the aircraft using the system.

  When the runway on which a PAPI system is equipped with an ILS, the units shall be positioned such that the approach slope conforms as closely as possible with the glide path of the ILS.

  The angle of elevation settings of the light units in a PAPI wing bar shall be such that, during an approach, the pilot of an aircraft observing a signal of one white and three reds will clear all obstructions in the approach area by a safe margin.

  Where PAPI wing bars are installed on each side of the runway to provide roll guidance, corresponding units shall be set at the same angle so that the signals of each wing bar change symmetrically at the same time.

Inspection Details:
The PAPI units are optically set in the factory and all that is required is  the setting of the units to the required approach angle. n some cases there may be a levelling device which is incorporated into the unit. In other cases a clinometers should  be utilised  to ensure that the desired angle is achieved. Lamps will be checked daily during routine airfield inspections.
The system shall be checked after any aircraft landing incident/accident

Reporting:
PAPI shall be considered unserviceable if one or both of the following occur:


DEGREE OF UNSERVICEABILITY STATUS
Failure of more than one lamp in each unit UNIT UNSERVICEABLE
Failure of any one unit SYSTEM UNSERVICEABLE

If PAPI is provided on both sieds of the runway, failure of a light unit in a symmetrical PAPI system may be tolerated by switching off completely the failed side, leaving PAPI operating only the serviceable side of the runway.

  Long grass or any obstruction obscuring light units shall be reported and action taken rectify the problem.

MORE PAI INFO!!!!

PAPI INFO!!

http://www.nrairport.com/equipment/PAPI.htm

http://www.flightlight.com/airportlighting/4.0/4.0.html

http://www.adb-air.com/en/productcenter/manuals/am02512/manual01.shtml

http://www.cbd-net.com/index.php/search/show/503800


Dave 

VASI INFO!!!

VISUAL  APPROACH  SLOPE  INDICATORS (VASI)—The VASI system provides the pilot with visual approach slope angle information while on final approach. The VASI system is helpful during daylight or night operations. There are three standard VASI system  configurations:  VASI-4.  VASI-12,  and  VASI- 16. We will discuss the VASI-12 system as it will appear on most Navy airfields. The VASI system consists of twelve light boxes with three lights in each box. There is one complete system for each end of the runway. There are two pairs of bars-one pair of bars on each side of the runway. Each wing bar is composed of three light boxes (fig. 6-36). The set of bars nearest the threshold is called the downwind bars. and the other pair. the upwind bars. Each light box projects a beam of light that is white (clear) in its upper part and red in its lower part. The lights are arranged so that the pilot of an airplane, during the approach. sees all of the wing bar lights as red  when  below  the  glide  slope.  When  on  the  glide slope. the pilot sees the downwind bar lights as white and the upwind bar as red. When above the glide slope, the pilot sees all the wing bar lights as white. FRESNEL®   LENS   OPTICAL   LANDING SYSTEM  (FLOLS).—Another  system  designed  for continuous  automatic  operation  is  the  FLOLS.  (See fig. 6-37.) It also provides optical landing assistance by indicating the correct glide slope angle to the pilot of an approaching aircraft. This system contains two groups of horizontal datum lights set perpendicular to the approach path; two vertical bars of wave-off lights; two double types of cut lights; and a source light indicator assembly, consisting of five vertical cell assemblies. Each cell assembly contains source lights, a Fresnel® lens. and a lenticular lens. The arrangement of these lenses gives the pilot the glide slope. The unit should be set up on the left side of the runway, from the pilot’s perspective, about 10 feet from the edge of the pavement and 750 feet from the runway threshold. Power for the system is provided by an installed field lighting supply or by an auxiliary, power unit capable of 20 kilowatt (kW). 60 hertz (Hz), three- phase, 120 volts phase to neutral. RUNWAY DISTANCE MARKER.—With  the use of high-speed aircraft, the runway distance marker system is needed to tell the pilots how much runway is left to take off or to land. The distance information, in thousands of feet, is given by numbers on the side of the marker. The numbers are on two sides of the signs, so that the distance left can be shown for both directions. There is one row of signs on each side of the runway. Each row is the same distance from the runway center



I'll take a case of your finest wine!!     RED!!!
Dave 

Think you have a lot of reading? I have just finished a 4298 word PC building article, and theres at least another 9 pages to go! Arr, my eyes will never be the same again!
Dan

AFAIK it's a box with a lamp in it, with a red and a white clolred aperture in it