NATS Transponder Use Survey
Thread Starter
Join Date: Jan 2010
Location: NATS Swanwick
Posts: 17
Likes: 0
Received 0 Likes
on
0 Posts
NATS Transponder Use Survey
As part of our re-invigorated relationship with the General Aviation community, NATS have decided to participate in the debate and discussion on the General Aviation forums by joining as a named position, in this case Jonathan Smith, NATS Infringements Lead. We hope that our occasional contribution to relevant threads will be both informative and constructive. In exchange, our participation allows us to formally understand, gauge and learn from the views of the many members of the GA community that contribute to the forums and may otherwise be difficult to communicate with.
One area of interest, which has proven very difficult to gather reliable data, is related to transponder use by the GA community. NATS have discussed recently at the Airspace Infringement Working Group and as a member of the General Aviation Safety Council why transponder equipped aircraft continue to operate without switching the transponder on or without selecting the altitude (Mode C) function when fitted. We know from infringement investigation reports that a percentage of infringing pilots have chosen either deliberately or mistakenly to not fully utilise the transponder fitted to their aircraft. Trying to understand and measure the actual scale of this issue and the reasons behind it, has proven hard to achieve from traditional sources of data.
Please would you consider spending a few minutes (There are maximum of 9 questions - dependant on answers given) contributing to the following electronic questionnaire to help us to better understand the issue? GA Pilot Transponder Survey
If you choose to help us in gathering this data, you should also be aware of the following;
The survey will close at 23:45pm on the 4th Feb 2010 or when 1,000 responses have been received if before the deadline date.
The survey won’t accept more than one response from the same computer.
Please be as honest as possible and note that there is an opportunity for you to provide reasons for your answers.
You should answer all questions based on the GA aircraft that you fly most frequently.
It is an informal survey by NATS and the responses will be treated anonymously. This is our first attempt at conducting a survey amongst the GA community in this way, so if we haven't got our questioning or methodology perfect, we are more than happy to hear from you.
Providing our first attempt runs smoothly we will, of course, share our findings via the forums.
Finally, we welcome your contribution and look forward to hearing your point of view.
One area of interest, which has proven very difficult to gather reliable data, is related to transponder use by the GA community. NATS have discussed recently at the Airspace Infringement Working Group and as a member of the General Aviation Safety Council why transponder equipped aircraft continue to operate without switching the transponder on or without selecting the altitude (Mode C) function when fitted. We know from infringement investigation reports that a percentage of infringing pilots have chosen either deliberately or mistakenly to not fully utilise the transponder fitted to their aircraft. Trying to understand and measure the actual scale of this issue and the reasons behind it, has proven hard to achieve from traditional sources of data.
Please would you consider spending a few minutes (There are maximum of 9 questions - dependant on answers given) contributing to the following electronic questionnaire to help us to better understand the issue? GA Pilot Transponder Survey
If you choose to help us in gathering this data, you should also be aware of the following;
The survey will close at 23:45pm on the 4th Feb 2010 or when 1,000 responses have been received if before the deadline date.
The survey won’t accept more than one response from the same computer.
Please be as honest as possible and note that there is an opportunity for you to provide reasons for your answers.
You should answer all questions based on the GA aircraft that you fly most frequently.
It is an informal survey by NATS and the responses will be treated anonymously. This is our first attempt at conducting a survey amongst the GA community in this way, so if we haven't got our questioning or methodology perfect, we are more than happy to hear from you.
Providing our first attempt runs smoothly we will, of course, share our findings via the forums.
Finally, we welcome your contribution and look forward to hearing your point of view.
Join Date: Apr 2003
Location: Midlands
Posts: 2,359
Likes: 0
Received 0 Likes
on
0 Posts
My personal opinion for what it is worth.
I fly a home built aircraft with mode A/C and collision avoidance that requires a transponder in the other aircraft to work. In my local area I regularly spot aircraft which I know, have a transponder but it is not activating the CA equipment so is not “on”. When asked afterwards pilots tend to say, “I forgot”, but if pushed it is the fear of getting caught infringing, which causes the brain fade. The high publicity incident of the Red Arrows airspace infringement in which of the four aircraft involved, only the one transponding was traced and the pilot prosecuted set a very bad example. Encouraging pilots to use their transponders and fit CA systems would benefit us all.
Rod1
I fly a home built aircraft with mode A/C and collision avoidance that requires a transponder in the other aircraft to work. In my local area I regularly spot aircraft which I know, have a transponder but it is not activating the CA equipment so is not “on”. When asked afterwards pilots tend to say, “I forgot”, but if pushed it is the fear of getting caught infringing, which causes the brain fade. The high publicity incident of the Red Arrows airspace infringement in which of the four aircraft involved, only the one transponding was traced and the pilot prosecuted set a very bad example. Encouraging pilots to use their transponders and fit CA systems would benefit us all.
Rod1
Join Date: May 2001
Location: 75N 16E
Age: 54
Posts: 4,729
Likes: 0
Received 0 Likes
on
0 Posts
I flew with someone recently who was a relatvely low houred pilot. When we were about to take off I asked him about the transponder being off. His reply was that we didn't need it as we were only going to be flying locally.
To me that is a baffling attitude considering the plane had a fully functional mode C transponder fitted, and I can only imagine it was down to his PPL training.
I fly with Mode C and the new aeroplane has Mode S and also use traffic avoidance systems regularly, and really I think it is stupid to have an aeroplane with a txpdr and not turn the thing on.
To me that is a baffling attitude considering the plane had a fully functional mode C transponder fitted, and I can only imagine it was down to his PPL training.
I fly with Mode C and the new aeroplane has Mode S and also use traffic avoidance systems regularly, and really I think it is stupid to have an aeroplane with a txpdr and not turn the thing on.
Join Date: May 2001
Posts: 2,118
Likes: 0
Received 0 Likes
on
0 Posts
Rod1 is spot on. Fear of prosecution for an inadvertent infringement (ie virtually all infringements) is a major deterrent to transponder use and is not helped by the example quoted by Rod or by all the publicity given for NATS controllers to "report" every single wing tip incursion.
There is of course also the die hard view of some old fashioned Englishmen that personal privacy rights mean that aircraft should be "seen and not watched" by a surveillance society.
There is of course also the die hard view of some old fashioned Englishmen that personal privacy rights mean that aircraft should be "seen and not watched" by a surveillance society.
Join Date: Jan 2004
Location: An ATC centre this side of the moon.
Posts: 1,160
Likes: 0
Received 0 Likes
on
0 Posts
Fear of prosecution for an inadvertent infringement
Thread Starter
Join Date: Jan 2010
Location: NATS Swanwick
Posts: 17
Likes: 0
Received 0 Likes
on
0 Posts
Backpacker
You make a good point, we should have made it clear. We are primarily interested in transponder use in the UK for the survey but would welcome your thoughts or experiences of transponder operation outside the UK as a contribution to the thread.
You make a good point, we should have made it clear. We are primarily interested in transponder use in the UK for the survey but would welcome your thoughts or experiences of transponder operation outside the UK as a contribution to the thread.
Join Date: Apr 2003
Location: North West UK
Posts: 147
Likes: 0
Received 0 Likes
on
0 Posts
I ALWAYS use the transponder. Having done all my training at EGCC, I appreciated the help that it gave to both me & ATC.
I use the listening code when using the M/cr LLR, or indeed anywhere around the M/cr zone. I've only been called occasionally, usually to advise of conflicting traffic and only once when in danger of accidentally drifting out of the corridor in poor vis.
The comfort factor works both ways, hopefully making life a bit easier for the ATC at MAN, and a 'safety net' for me. I'd sooner be 'shouted' at rather then receive a 'phone call or a letter after the flight!
When flying across hostile terrain it could be a life saver should you have a problem, always assuming that radar can still see you and that you are talking to someone. Why take chances?? It's a bit like driving without headlights on in poor visibility....
I use the listening code when using the M/cr LLR, or indeed anywhere around the M/cr zone. I've only been called occasionally, usually to advise of conflicting traffic and only once when in danger of accidentally drifting out of the corridor in poor vis.
The comfort factor works both ways, hopefully making life a bit easier for the ATC at MAN, and a 'safety net' for me. I'd sooner be 'shouted' at rather then receive a 'phone call or a letter after the flight!
When flying across hostile terrain it could be a life saver should you have a problem, always assuming that radar can still see you and that you are talking to someone. Why take chances?? It's a bit like driving without headlights on in poor visibility....
Join Date: Jun 2003
Location: Essex
Posts: 128
Likes: 0
Received 0 Likes
on
0 Posts
I am currently only flying club aircraft. While these are all fitted with mode c transponders, there are often periods (months not weeks) when the mode c function is u/s in a particular aircraft. If this is common to club aircraft, I would imagine these would account for a fair percentage of the "fitted but not transponding" aircraft that have been referred to.
That said, when it works I use it. I'm pretty inexperienced and take the view that I need all the help I can get!
That said, when it works I use it. I'm pretty inexperienced and take the view that I need all the help I can get!
Join Date: Dec 2006
Location: .
Age: 37
Posts: 649
Likes: 0
Received 0 Likes
on
0 Posts
I operate in a busy Class D environment requesting squawk regularly, and as such was taught as a student to always switch on the transponder. Even if away from my home airspace in the open FIR I have the transponder switched on. Fisbangwallop and his colleagues usually ask us to squawk 7401 anyway if we are using 119.87.
At least if you are being painted by a radar unit you are easily identified if you have a squawk. Useful if things go mammaries skyward for whatever reason...
Don't understand people who fly around with the transponder switched off... if its there, use it.
Smithy
At least if you are being painted by a radar unit you are easily identified if you have a squawk. Useful if things go mammaries skyward for whatever reason...
Don't understand people who fly around with the transponder switched off... if its there, use it.
Smithy
Join Date: Jul 2004
Location: On the wireless...
Posts: 1,901
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by mad_jock
The pilots in my experence far more likely to operate without a trasponder are.....the ones that hold a ATCO license.
Join Date: Jun 2003
Location: EuroGA.org
Posts: 13,787
Likes: 0
Received 0 Likes
on
0 Posts
Nontransponding traffic is totally baffling on the occasions when it is visually identified and quite obviously it is a new-ish type plane which will obviously be carrying a transponder.
That some people fly with the TXP switched off, allegedly to avoid getting busted for a CAS bust, would be utterly stupid and an appalling testament to the "quality" of PPL training which is still teaching WW2 (no, actually WW1) nav techniques and no GPS.
Unless, following the bust, one flies back home at a pretty low level, there will be a radar track left somewhere, enough to follow if one has made a real exhibition of oneself and the motivation is there. What they probably cannot then establish is which plane based at that airfield did it, because the records are usually a bit slack. But having Mode C on is not going to affect that. Mode S would allow the plane to be traced by the 24 bit code, assuming it has been correctly configured.
But the CAA rarely prosecutes CAS busts. They seem to go after high public profile stuff like airshow TRA busts (like that bloke from Belgium who got done a few k for busting the Eastbourne show). To get prosecuted for a CAS bust, you would need to bring down Heathrow, and then tell the interviewer that the UK is a free country and you are allowed to do this.
I've done the survey. Mode S always on. It has to be said however that for the CAS bust context, Mode C is just as good.
That some people fly with the TXP switched off, allegedly to avoid getting busted for a CAS bust, would be utterly stupid and an appalling testament to the "quality" of PPL training which is still teaching WW2 (no, actually WW1) nav techniques and no GPS.
Unless, following the bust, one flies back home at a pretty low level, there will be a radar track left somewhere, enough to follow if one has made a real exhibition of oneself and the motivation is there. What they probably cannot then establish is which plane based at that airfield did it, because the records are usually a bit slack. But having Mode C on is not going to affect that. Mode S would allow the plane to be traced by the 24 bit code, assuming it has been correctly configured.
But the CAA rarely prosecutes CAS busts. They seem to go after high public profile stuff like airshow TRA busts (like that bloke from Belgium who got done a few k for busting the Eastbourne show). To get prosecuted for a CAS bust, you would need to bring down Heathrow, and then tell the interviewer that the UK is a free country and you are allowed to do this.
I've done the survey. Mode S always on. It has to be said however that for the CAS bust context, Mode C is just as good.
Join Date: Aug 2003
Location: Not a million miles from EGTF
Age: 68
Posts: 1,579
Likes: 0
Received 0 Likes
on
0 Posts
You may be right about the prosecution side of things.
But what concerns me is that over the past 2 years the number of reports of incursions on the monthly report around certain large airfields has gone up.
I would doubt that is due to a worsening of pilot skills (although quite possible) but rather due to greater reporting.
Why would that be? Possibly so that NATS can go to the CAA and beg for more CAS to protect the self-loading freight.
I think a more reasoned approach would be to look at why incursions happen and redesign the airspace to improve things - being restrictive is something different.
There are a whole lot of 'pinch spots' (Luton -Stansted gap for one) where airspace design is poor and minor errors in navigation can put you in the brown stuff fairly quickly.
This questionnaire, well-meaning as it may be, isn't going to help make us feel 'loved' by NATS, but will probably be seen as a pre-emptive attack on many of us (just as the TMZ was)
But what concerns me is that over the past 2 years the number of reports of incursions on the monthly report around certain large airfields has gone up.
I would doubt that is due to a worsening of pilot skills (although quite possible) but rather due to greater reporting.
Why would that be? Possibly so that NATS can go to the CAA and beg for more CAS to protect the self-loading freight.
I think a more reasoned approach would be to look at why incursions happen and redesign the airspace to improve things - being restrictive is something different.
There are a whole lot of 'pinch spots' (Luton -Stansted gap for one) where airspace design is poor and minor errors in navigation can put you in the brown stuff fairly quickly.
This questionnaire, well-meaning as it may be, isn't going to help make us feel 'loved' by NATS, but will probably be seen as a pre-emptive attack on many of us (just as the TMZ was)
Join Date: May 2006
Location: Londonish
Posts: 779
Likes: 0
Received 0 Likes
on
0 Posts
One reason I have (and do) leave txp off is doing aerobatics under busy airspace - No intention of busting, but I'm of the belief that a signal heading up at a great rate of knots directly underneath the big tin might cause a few issues; despite the fact that there's no way I've got enought energy to get there - plus I'm moving sufficiently erratically I'd consider the signal to be just 'noise'. Otherwise, it's firmly on.
Join Date: May 2001
Posts: 10,815
Likes: 0
Received 0 Likes
on
0 Posts
Unfortunately I am serious.
Its not just CAS busts that folk turn them off.
And to be honest I don't think its your average PPL that does turn them off. Its the ones that do know the rules and do know how the system works that are turning them off for "tactical reasons". Ie the ones that really don't care if you MOR them because they know the rules and know they are legal.
No evidence for
Rule 5 busts
Noise abatement busts
Danger area busts (where the calibration of the radar has been know to be out for several years ie your 3 miles off shore feet wet and they reckon your flying over the land)
etc etc.
By far the most common tactical squawk reason for controllers was so certain Mil units couldn't see them. Along the lines of if those bastards can't keep there traffic away from my approaches and co-ordinate when I am doing radar they can go
themselves if they think I am going to help them. There are other issues with being seen by Mil units but personaly I prefer to have the squawk on and refuse there suggestions than not having TCAS aircraft not be able to use my data.
Another issue is that some airports want the mode C in a circuit and others don't. I had one visiting pilot get his ear chewed out on frequency for having it on. When he informed the controller he was just obeying the current AIC on the subject he got an ear full.
So there are many reasons why people don't squawk.
PS please note when I have one and it is working I always have it turned on to Charlie.
Its not just CAS busts that folk turn them off.
And to be honest I don't think its your average PPL that does turn them off. Its the ones that do know the rules and do know how the system works that are turning them off for "tactical reasons". Ie the ones that really don't care if you MOR them because they know the rules and know they are legal.
No evidence for
Rule 5 busts
Noise abatement busts
Danger area busts (where the calibration of the radar has been know to be out for several years ie your 3 miles off shore feet wet and they reckon your flying over the land)
etc etc.
By far the most common tactical squawk reason for controllers was so certain Mil units couldn't see them. Along the lines of if those bastards can't keep there traffic away from my approaches and co-ordinate when I am doing radar they can go
themselves if they think I am going to help them. There are other issues with being seen by Mil units but personaly I prefer to have the squawk on and refuse there suggestions than not having TCAS aircraft not be able to use my data.Another issue is that some airports want the mode C in a circuit and others don't. I had one visiting pilot get his ear chewed out on frequency for having it on. When he informed the controller he was just obeying the current AIC on the subject he got an ear full.
So there are many reasons why people don't squawk.
PS please note when I have one and it is working I always have it turned on to Charlie.
Join Date: May 2001
Location: 75N 16E
Age: 54
Posts: 4,729
Likes: 0
Received 0 Likes
on
0 Posts
One reason I have (and do) leave txp off is doing aerobatics under busy airspace - No intention of busting, but I'm of the belief that a signal heading up at a great rate of knots directly underneath the big tin might cause a few issues; despite the fact that there's no way I've got enought energy to get there - plus I'm moving sufficiently erratically I'd consider the signal to be just 'noise'. Otherwise, it's firmly on.
If you left the txpdr on, squwarking 7004 or whatever the aero's code is, then at least if I am flying in the general area I can a) see you on the traffic screen and b) if talking to ATC they can advise me "of someone doing aerobatics in your 12 o'clock".
ATC can advise other traffic of "an aeroplane doing aerobatics below controlled airspace" and hence there is no issue. Turning it off seems completely daft to me.
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
I'm partially with Mark1234 on this one. I'm not a commercial pilot but what has been explained to me is that their TCAS system do extrapolation of mode-C transponder returns to determine where the traffic is going to be in a few seconds time. If you happen to be underneath an airliner and zoom up, the TCAS will extrapolate this zoom and issue a TCAS alert. I don't know the exact SOP, but AFAIK certain types of alerts/resolution advisories are mandatory for the crew to follow up. So the airliner will take (unnecessary) avoiding action.
I think this became SOP after a FedEx hit a Russian plane somewhere north of Switzerland a few years ago.
It's for this same reason that glider pilots (now fitted with mode-S in the Netherlands) have been given the advice only to activate the transponder after they've released the winch rope on top of the launch. Apparently the winch launch would trigger TCAS alerts several 1000s of feet above the launch field.
But on the other hand - when doing aerobatics your lookout is severely restricted and you need all the help you can get in identifying and avoiding other traffic. A working transponder makes an incredible difference.
For me personally, my aerobatics are limited to controlled airspace on one side, making a transponder (mode S) mandatory, and we do this on a discrete squawk from ATC, or underneath the Schiphol SRZ, where transponders are required to be on standby anyway. So it's a no-brainer for me.
I think this became SOP after a FedEx hit a Russian plane somewhere north of Switzerland a few years ago.
It's for this same reason that glider pilots (now fitted with mode-S in the Netherlands) have been given the advice only to activate the transponder after they've released the winch rope on top of the launch. Apparently the winch launch would trigger TCAS alerts several 1000s of feet above the launch field.
But on the other hand - when doing aerobatics your lookout is severely restricted and you need all the help you can get in identifying and avoiding other traffic. A working transponder makes an incredible difference.
For me personally, my aerobatics are limited to controlled airspace on one side, making a transponder (mode S) mandatory, and we do this on a discrete squawk from ATC, or underneath the Schiphol SRZ, where transponders are required to be on standby anyway. So it's a no-brainer for me.