Cobalt,
I can’t remember when Biggin introduced 7047, but it was quite a few years ago, so at least there such a state of affairs could no longer exist there now.
Did you get any insight from them on the reason why? And why do they switch of transponders? Are they installed, but just switched off, or aren’t they installed?
Why not repair a broken encoder? It costs a few hundred quid. School planes are generally run on a minimal-spend manner here in the UK (and many other places I have been to, on the ground). PPL training is often a race to the bottom with anybody setting up a PPL school in a little wooden hut. There were 8 (eight) fixed wing schools at EGKA when I was doing my PPL. Of course there are deeper issues there (why allow 8 schools to set up? – later leases tried to prohibit it) but that’s another topic.
As for deeper reasons/motivations, I suggest reading further back up this thread e.g. here
On the ground, I have never seen a “normal powered plane” which is in any sort of current flying use and which didn’t have a Mode C or S transponder in the panel. Maybe some are actually faulty but IMHO clearly the vast majority of these planes which don’t show up on TCAS at all are turned off by the pilot – either due to having been trained/told to do it or for some nefarious reason.
The UK has some bottlenecks in its Class G e.g. the Luton/Stansted passage
where if transiting along the magenta line shown you need to be below 2500ft and obviously not being Mode C and flying at say 3000ft is dangerous. I thought they made this a TMZ but can’t see a reference to it. Probably the reason why there has not yet been a CAT-GA collision is (a) due to the high perf of modern jets so maybe there is no traffic there below a good margin (one could check that with FR24) and (b) almost no GA in the UK flies much higher anyway. If you look at my above-linked post you see that the owner of the plane (a school, probably) put a sticker on the transponder asking the pilot to turn it off in that very area, so a bust would not be detected! I didn’t post the pic of the sticker because I don’t want to “steal” a photo from another forum.
Unfortunately this stuff is real… slag me off again as you wish.
Peter wrote:
slag me off again as you wish.
Peter, I don’t have anything against you. However for some reason you see issues which others including me don’t experiance. Someonce experiance is not always right. I just try to find out why. Because if your statement is correct, then it would be correct if changes are made.
Cobalt wrote:
Then we flight-tested them all with ATC units. Turns out, half of them weren’t working properly… so we got them fixed. Mostly antenna or wiring stuff.
Weren’t these test as part of scheduled maintenance? This was part of LAMS / LAMP at those days?
However for some reason you see issues which others including me don’t experiance
Probably a combination of
Weren’t these test as part of scheduled maintenance? This was part of LAMS / LAMP at those days?
Maybe, but a maintenance company has to do as instructed by the school (within reason) otherwise they will lose their business. I don’t know the UK regs on radio checks but clearly an altitude encoder is not a mandatory item at the Annual on a G-reg.
Peter wrote:
I don’t know the UK regs on radio checks but clearly an altitude encoder is not a mandatory item at the Annual on a G-reg.
That is not true, to be honest, I don’t know ANY country which doesn’t require at least altimeter + transponder including mode C verification
That is the reason for asking. There is also a regulation under EASA that if there is something wrong with mode C you need to adress this before further flight.
Are you sure that your TAS system perform upto specs, as you also report limited range every now and then?
If this happens at your homefield, did you every discussed this with flying instructors are your field, what is their view? Cobalt post seems to suggest there were issues with either encoder or limited RF output / sensitivity. When you accounter such system, and your TAS system power output is gone (I have seen issues on this, where the unit was lacking RF transmit power, or reduced sensitivity.
Timothy wrote:
I can’t remember when Biggin introduced 7047, but it was quite a few years ago, so at least there such a state of affairs could no longer exist there now.
Before that. But since the transponder isn’t mandatory, it was a " shrug your shoulders" moment when one well-known aircraft couldn’t.
But I agree – over time it has become less and less accepted to turn up without one when you should, and definitely the instructors got more diligent putting them on the defects sheet.
Jesse, you can keep repeating this over and over but I have already posted photos of the TCAS and of the plane just landing right next to me, and spoken to the owner, and was told they have a duff encoder and won’t fix it… I am going to give up on this now. I have already posted tons of stuff but you refuse to believe it. You can come over and see for yourself. I guess you deal with a different population of pilots. GA is like that. Some companies see only one cross-section, others see others. One shop I know does only repairs of 1970s radios and has never done a GTN box. Another has installed maybe 100 GNS430 boxes and never wired up the OBS (he is not an IFR pilot so doesn’t know). Also a lot of people don’t talk about stuff for reasons/agendas of their own. Also some pilots fly only with a certain cross-section of other pilots, drawn from those who hang out on the forums on which they hang out, who turn up at certain meetings, etc, and who contact them. I don’t hang out with anybody who will deliberately turn a transponder off (most will find EuroGA very boring actually; they hang out elsewhere) but I definitely know some personally and there are large groups in Europe who turn off Mode S totally (if installed) because they are “foreign reg” homebuilts staying over the 6month (or whichever) time limit. Maybe Netherlands has a high compliance %, whereas the UK tradition is for minimal compliance. CAA enforcement probably varies; in the UK there is virtually none. Around Europe, this stuff correlates with enthusiasm for the EU also… But these cultural variations across Europe (they are extremely obvious close-up; I could tell hilarious stories of e.g. how one famous company reduced the value of an aircraft to near zero but the owner still says they are great, which would never happen in the UK – a UK pilot would not ever use them again) cannot be discussed without one getting shot at.
Peter wrote:
Around Europe, this stuff correlates with enthusiasm for the EU also…
Let’s not bash the EU for any and all evil. Switzerland has a 100% compliance rate (not only in matters aeronautical) enforced by aggressive policing yet the general public does not have much enthusiasm for the EU.
Cobalt wrote:
since the transponder isn’t mandatory, it was a " shrug your shoulders" moment when one well-known aircraft couldn’t.
I don’t want to do this to death, but your assertion was that before 2012 instructors at your club simply didn’t know that Mode A or C wasn’t working.
I can’t really see how that works at Biggin. Both departing and arriving you are instructed to squawk 7047.
The response “Negative squawk” is indeed perfectly acceptable, but you, in your club aircraft, which you believe to have working transponders, would not reply that. You would reply “Squawk 7047”.
If they then didn’t see that on the ATM in the Tower, they would tell you, and you would then know, and ask Singh or Tony to fix it.
As a late answer to Aviathor post, I confirm that in France most pilots have their transponder turned on when they fly. However, I used to hear some guys saying that they keep it turned off to avoid “problems with ATC”. A stupid move in my opinion.
It is very difficult to know for sure how many pilots do it, no matter what they say or don’t say in a forum thread.
