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msyairtran

ILS vs LOC

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Can someone explain the difference in a ILS runway and a LOC runway? Seem like the localizer will bring me down on a ILS runway but I have a hard time on a LOC runway.

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I have no professional background in these things but logic tells me a LOC-equipped runway will have lateral guidance only. It's up to you to control your descent.Using the 1 in 3 rule you should be 3000ft AGL 9 miles out reducing to 3000ft 1 mile out. A descent rate around 1200fpm at 160kts shouldn't be too far off.Hope that helps.

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"Using the 1 in 3 rule you should be 3000ft AGL 9 miles out reducing to 3000ft 1 mile out." As ever, Ray, your logic is flawless! The standard heights for a 3 degree glidepath are 3000ft at 10nm, 1500ft at 5nm and so on. However, as most people fly altitude rather than height on approach these days (I doubt if many of our users will have even heard of QFE let alone used it:-)) it is necessary to add the airfield elevation to the quoted heights to get the correct altitudes. "A descent rate around 1200fpm at 160kts shouldn't be too far off."I think 1200fpm may be a little high at least for a standard 3 degree GP. To maintain a 3 degree glidepath, a height loss of 300 ft per mile is required. Obviously, the actual descent rate to achieve this loss depends on your ground speed but I would have thought that 800-900fpm was a little nearer the mark at the UK standard 160KIAS to 4 dme.BestPete

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Thanks for dropping in Pete. Spot the amateur advice versus that of a professional. ;-)In my defence I would just say I like the firmer type of landing. Of course that descent rate would not go all the way down to the ground. Killing the engines around 30ft and a slight flare for that perfect landing!I just noticed my big error... you should be 3000ft AGL 9 miles out reducing to 3000ft 1 mile out.That should be 700-900ft 1 mile out.Cheers,

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