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Old 22nd Dec 2005, 13:24
  #280 (permalink)  
jondc9
 
Join Date: Dec 2005
Location: USA
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ILS GLIDESOPE

OK

any pilot will tell you that the ILS glideslope is virtually sacred in bad weather conditions. Regulations do allow for descent below the glideslope when required for a safe landing.

somewhere around the middle marker...but MDW doesn't have a middle marker.

I will tell you right now during good weather many pilots "duck" the glideslope to land closer to the threshold of the runway.

BUT on a dark, snowy, stormy night you simply must stay on the glideslope until the wheels are over the concrete.

SADLY, I think that southwest procedures and calculations may assume that you land at the displaced threshold...this would have given the extra 800 odd feet to stop.

the trouble with that theory is that you coudn't see the threshold and the glideslope leads you almost 1000' down the runway from there. ON top of all of that the concept of flare delays touchdown. By the way, an airplane can handle a firm touchdown to about 600fpm...more than that requires a "hard landing inspection".

the chicago tribune is reporting today that southwest had a visibility wavier to allow approaches with 1/4 mile LESS visibility than
published.

a mistake if you ask me. while it is one thing to land in lower visability with calm or head wind on a good runway, add ICE, and tailwind and 3 strikes your out!

jon
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