Re: loss of glideslope

Date:         30 Mar 99 01:53:31 
From:         mike paterson <>
Organization: GEC Marconi avionics
References:   1 2 3
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Glideslope on ILS is UHF whereas the localiser and Marker are both VHF. UHF
is more prone to atmospheric attenuation. a good rule of thumb is that V/UHF
comms are good for 200 miles at 10,000 feet. So at maximum range the UHF
i.e. the Glideslope will suffer more atmospheric ( water and Oxygen)
attenuation than the localiser.