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Old 28th Jun 2010, 16:22
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Chimbu chuckles

Grandpa Aerotart
 
Join Date: Jun 2000
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Counting lights?

I have been instrument rated for 23 years - flown the odd ILS to minimas - NEVER have I counted lights, never even occurred to me.

Maybe I need to spend more time in Flight Sim?

Before you fly an ILS you need to have an understanding of what you will likely see at the minima with min vis. That depends on the published minimum vis - it might be the threshold or it more likely be the first bit of the HIALS for Cat 1.

A standard ILS brings you down at 320'/nm. At a typical DA of 220' (BN 19ILS) you will be 1270m from the touchdown zone - min vis, 800m, you MIGHT see the runway end lights but no way the VASI - you will see the the HIALS. Remember too the reported vis is not reported through a windscreen doing 90-120kts. If they say 800m in rain you will likely have less REAL visibility at the minima - ****ty windscreen wipers not withstanding - doesn't mean you second guess them either - they say 800m you're good to go and use that command judgement you're payed so well to exercise from time to time.

Count lights - you gotta be kidding?

If you see anything vaguely resembling what you expect to see you're visual - you don't and you're not. You make an instant decision.

How much counting of lights you see happening here? This is the CNS Rwy 15 ILS - anyone know the minima, its been too long since I landed there.


Last edited by Chimbu chuckles; 28th Jun 2010 at 16:43.
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