Signal Protection
Joined: Apr 2004
Posts: 129
Likes: 0
From: Manchester, UK
EI-MICK,
One aspect of this that I am aware of is that maneouvering aircraft are not allowed as close to the runway, so for example aircraft waiting to line-up/cross the runway in use must wait at a holding point more distant than the usual holding point.
(You usually see these holding points specifically marked, for example F3 CAT II/III if F3 was the holding point.)
The reason: aircraft on CAT II & CAT III approaches are using the ILS to a lower height, and a big lump of metal near a transmitter will interfere with radio signals - so keep the aircraft further from the runway so it can't interfere with the ILS.
Just out of interest, aircraft on CAT II appraoches have a minimum decision height of 100ft, CAT IIIA approaches 50ft, and CATIIIB approaches 0ft.
Hope this helps,
POL
One aspect of this that I am aware of is that maneouvering aircraft are not allowed as close to the runway, so for example aircraft waiting to line-up/cross the runway in use must wait at a holding point more distant than the usual holding point.
(You usually see these holding points specifically marked, for example F3 CAT II/III if F3 was the holding point.)
The reason: aircraft on CAT II & CAT III approaches are using the ILS to a lower height, and a big lump of metal near a transmitter will interfere with radio signals - so keep the aircraft further from the runway so it can't interfere with the ILS.
Just out of interest, aircraft on CAT II appraoches have a minimum decision height of 100ft, CAT IIIA approaches 50ft, and CATIIIB approaches 0ft.
Hope this helps,
POL
Thread Starter
Joined: Mar 2003
Posts: 155
Likes: 0
From: Location
excellent,exactly what i wanted.I was aware of the interference etc with the signal,but was unaware of the procedures on the ground and keeping aircraft at the relevent CAT holds,thanks for the quick reply PH.
thanks im aware of the CAT 1,2,,3 approach minimums.Thanks
thanks im aware of the CAT 1,2,,3 approach minimums.Thanks
