Hi Y'all,
Believe Londion City is towards 6* GS angle! Ok, my thoughts on Ground Station Equipment.
Localiser and Glideslope equipments are very similar, and only slightly different. Their frequencies are related and by setting the LOC frequency in the cockpit, the GS part of the equipment will also be on the correct freq.
The GS groundstation transmits the two beams stacked one ontop of the other, and the LOC sends them out side by side.
The 'two beams' sent out are modulated at 90 and 150 Hz respectively. So you can see that when you fly in the centre of the two beams there is '0' difference - hence a 'centre' reading on the cockpit instrument.
The position of the LOC ground equipment is at the distant end of the runway you are trying to land on. This means that the centre of the beams will be on the centre of the runway along its entire length. There are a few places with offset LOC's but we won't get confusing with that today!
The position of the GS ground equipment is relative to that runway's touchdown point. Follow the needle = land at touchdown.
Hope thats an simple explanation.
mjtibbs - sorry, it's just MS FS that cannot auto-flare correctly!
Cheers
Bear 555
(Pilot and ATC Systems/Navaids Engineer)