Mode C under a CTA
Joined: Nov 2001
Posts: 1,122
Likes: 0
From: uk
Bandit,
As a far as the military it leaves very small margin for error under our CTA,with the high ground.Thats why if they have a low level abort,the first we know about it is they are well in CAS.Things happen quickly at 500kts.
Thats the joys of being surrounded by class G,and a low level playground.
As far your other point,if they are not squawking,or mode A only,then the controller has no way of telling that a/c is in or out of CTA.We therefore ASSUME that the target is out,unless we have information that it's lost etc.
I have seen the military infringe the CTA,then realise what they've done,and switch off the transponder.They then get out of the CTA quick,then switch it on again.
The only conflict alert I've used worked on mode c readouts,and also a rate of closure.However at ABZ we don't have conflict alert on the radar at all.Got to keep your eyes peeled all the time with mil under the CTA.
As a far as the military it leaves very small margin for error under our CTA,with the high ground.Thats why if they have a low level abort,the first we know about it is they are well in CAS.Things happen quickly at 500kts.
Thats the joys of being surrounded by class G,and a low level playground.
As far your other point,if they are not squawking,or mode A only,then the controller has no way of telling that a/c is in or out of CTA.We therefore ASSUME that the target is out,unless we have information that it's lost etc.
I have seen the military infringe the CTA,then realise what they've done,and switch off the transponder.They then get out of the CTA quick,then switch it on again.
The only conflict alert I've used worked on mode c readouts,and also a rate of closure.However at ABZ we don't have conflict alert on the radar at all.Got to keep your eyes peeled all the time with mil under the CTA.
Thread Starter
Joined: Nov 2006
Posts: 167
Likes: 0
From: EGLL 270° 4DME
throw_a_dyce: fascinating insight- cheers
.
But pls forgive me if I appear like a stuck record here..but I find it very hard to believe a controller would allow two radar returns to merge purely on the assumption the non-squawking/modeA aircraft is not infringing. Would you just sit there with fingers crossed under the desk hoping that the unidentified a/c is not at the same level? (I take it a verbal traffic advisory would be issued to the controlled traffic at the least?).
.But pls forgive me if I appear like a stuck record here..but I find it very hard to believe a controller would allow two radar returns to merge purely on the assumption the non-squawking/modeA aircraft is not infringing. Would you just sit there with fingers crossed under the desk hoping that the unidentified a/c is not at the same level? (I take it a verbal traffic advisory would be issued to the controlled traffic at the least?).
Joined: Mar 2003
Posts: 437
Likes: 0
From: UK
On a related topic - there are certain aerdromes that fall just within the London CTR. Obviously there are rules governing joining, circuits, departure etc, so as not to conflict with London inbound/outbound traffic. What therefore is your take on transponder use in the circuit or in vicinity of the aerodrome?
Some aerodromes advocate transponder on standby in the circuit, but mode C when departing. Would it not be a lot easier at these fields if everybody squawked charlie all of the time? Surely there is enough seperation at these places as not to invoke a TA, and wouldn't it make the picture clearer to controllers (instead of just getting primary returns?)
I understand there was also some consideration to use a generic circuit squawk code, which would sure help at these fields (again with "c") Whatever happend to that?
Some aerodromes advocate transponder on standby in the circuit, but mode C when departing. Would it not be a lot easier at these fields if everybody squawked charlie all of the time? Surely there is enough seperation at these places as not to invoke a TA, and wouldn't it make the picture clearer to controllers (instead of just getting primary returns?)
I understand there was also some consideration to use a generic circuit squawk code, which would sure help at these fields (again with "c") Whatever happend to that?
