View Full Version : Mode S at LHR
Thunderbug
26th Oct 2005, 15:02
I see in the new AERAD pages for LHR that when we arrive on stand we are to select 1000 on the transponder before turning it to OFF/STBY.
I must be something to do with the mode S / Ground surveillance kit, but just curious - Why? What difference does it make if i just switch the damn thing off? :}
T'bug :ok:
I suspect (however await a full answer from someone in ATC Ops) it is to do with any towing movements of aircraft to allow the callsign to be displayed on our ground radar.
Thunderbug
26th Oct 2005, 15:16
GT3
Cunning plan... hadn't thought of that!
but do our illustrious towing crews select the transponder to a "broadcast" position?
T'bug
T'bug I'm not entirely sure. Do you have three settings for the transponder? Its not the fully off or the fully on I think you need to set it to. However again I stand to be corrected as I only have a limited technical knowledge of this as I tend to only use the end result on the ground radar. Pop up to the tower for a visit sometime too!
Giles Wembley-Hogg
15th Dec 2005, 11:28
I still don't get it. Why do we have to select 1000 BEFORE selecting STBY? Why not select STBY first, then type in 1000? Or is this just a note in the AERAD guide which is not supposed to be taken literally?
G W-H