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Please explain these PAPI lights.

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These, I believe are PAPI lights - as opposed to the VASI lights common at US airports in Fs2002. They seem to be used everywhere in Australia and some other countries in FS2002 and unfortunately are a lot dimmer than the US style VASI lights.When you are too low -- they are all red. A bit higher and they go white and then as you go higher still, they change from little whites in front of the big white to little whites behind the big white.Could somebody tell me how they are meant to be used please.Thanks Barry

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They're an ingenious system.In each housing are a red and a white light. Depending on your angle towards the lights you see the red one or the white one.If you're at a steep angle (in other words, high) you cannot see red. If you're shallow (low) you cannot see white.Nothing electronic, no moving parts at all.

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Barry,PAPI is a visual approach path indicator system consisting of 4 lights situated on the left side of the runway in the form of a wing bar (ie at right angles to the runway). The aircraft is on slope if the two units nearest the runway show red and the two units furthest from the runway show white. Too high if all units show white, too low if all units show red. A PAPI can be situated so as to provide 3 types of eye-to-wheel height (P1 = 10ft, P2 = 25 ft, P3 = 45 ft).As a side note, PAPI and VASI in FS2K are unreliable at many airports because they are not positioned corrected, ie at the glide-path intercept point on the runway.Kevin in CYOW

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>Maybe I'm wrong, but isn't that PAPI and VASI at the same >place, with the top bar of five lights being the PAPI >system? >I think greeger is right. The first 3 rows seem to be a 3-row (go figure :) VASI. While the last row of 5 (?) lights is the PAPI set.With VASI you're looking for white OVER red. (In a 3-row VASI the first 2 rows are for small aircraft, the last 2 rows are used by large aircraft)With PAPI, it's white BESIDE red. Here in the US PAPI uses 4 lights .. not sure elsewhere, but 5 seems odd. On glidepath you should see 2 white lights on the left and 2 red lights on the right.If a runway uses both, normally the VASI's are on one side and the PAPI's on the other.Martin JensenKBED

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>Barry, >>PAPI is a visual approach path indicator system consisting >of 4 lights situated on the left side of the runway in the >form of a wing bar (ie at right angles to the runway). The >aircraft is on slope if the two units nearest the runway >show red and the two units furthest from the runway show >white. Too high if all units show white, too low if all >units show red. These lights do NOT show a mixture of reds and whites . They are either all red (too low) or all white. When they are all white , they go from the long 5 light bar with the smaller 3 light bars in front to a situation where the short white bars are behind the long white bar (depending on altitude)Barry

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Thanks for that fermin - will read it.These approach lights in the sim for Australian airports are very dim compared with the ones in the US (and elsewhere) Barry

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If I'm not mistaken, there is a little saying:ALL white, ALL rightALL RED, you're deadSomething like that ... all shite, you're above the glideslope for the runwayAll red, you're below the glideslope and ready to plow into the groundI thin if the runway has a published 3 deg glideslope, 2 white 2 red means you're on the glideslope

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Hi guys,The Visual glide slope indicators in the picture are of the VASI configuration.There are (in the world) today between 9 and 12 different types of VASI

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Barry,I don't know how they work in Oz but here in Canada they are as I describe above, a mixture of red and white depending on where you are on the glide path (as I have attempted to depict below).W W W W too highW W W R Slightly highW W R R On glide pathW R R R Slightly lowR R R R Too lowKevin in CYOW

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To add up to the confusion I think it went: "Red over White it's all right, White over Red you're dead".

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>With VASI you're looking for white OVER red.That would be true only if you were doing your approach inverted. :-eek You want red OVER white for a normal approach.

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