[Full Metal Jackass]

FYI: Until 2012 it was standard practice to leave the transponder switched off until lining up because

'with older radar systems, transponder operation on the ground could cause interference and multiple targets on the radar display. Modern digital systems can filter out transponders close to the antenna.'

FYI, we're in the second half of 2017. There was an AIC about half a decade back.

Are you now going to tell me you've received, read and understood every AIC over the past 5 years? Ok, if you work in the industry, it can be expected but those of us who are weekend hobby flyers, you can't really expect us to be aware of ALL changes, especially where the guidance changes so frequently.....

[Flying_john]

[quote..................... semi-serious. Our lights burn out quickly, and are dim enough that they only aid conspicuity at night. And I've never understood why people turn on landing lights when taking off [/quote]

Me too - until we recently fitted all LED lights, Nav, Landing, Strobe etc, now the ammeter hardly changes when they are all switched on - so thats what we do switch it all on.

Oh - unless we forget of course !

[T67M]

Always used it. Its fully automatic as its linked to the GNS so I would have to make a conscious decision to turn it off.

This assumes that the automatics work. My transponder is automatic, but one group member said it always failed for them. On investigation it transpired that the sequence you turn on other bits of kit could inhibit the auto-ALT function. I now always check at around 500' just after the flaps have come up.

Get it fixed then.......

You can't "fix" it as it's not broken. It's working exactly as described in the manual, namely the intentional inhibiting of the auto function which is present in both the GTX330 (non-ES) we used to have and the AXP340 we now have.

[Nomad63]

So far in the poll 9 people sometimes forget?, I'm quite surprised at that.

[Nomad63]

A poll for people who fly aircraft with transponders fitted

One thing to remember is that the results are only going to be representative of a subset of a subset of aviators - i.e., those PPLers who read the Flyer Forum and of those number, the ones who respond to the poll.

Not forgetting those who lie because they won't want their friends / peers to know that they fly with their transponders off.

It's an anonymous poll

[Full Metal Jackass]

So far in the poll 9 people sometimes forget?, I'm quite surprised at that.

I'm more surprised that 2 owned up to the fact that they would turn it off because of concerns about being punished..... unless........

[Dave Phillips]

FYI: Until 2012 it was standard practice to leave the transponder switched off until lining up because

'with older radar systems, transponder operation on the ground could cause interference and multiple targets on the radar display. Modern digital systems can filter out transponders close to the antenna.'

FYI, we're in the second half of 2017. There was an AIC about half a decade back.

Are you now going to tell me you've received, read and understood every AIC over the past 5 years? Ok, if you work in the industry, it can be expected but those of us who are weekend hobby flyers, you can't really expect us to be aware of ALL changes, especially where the guidance changes so frequently.....

No, I pointed you towards a document that clarified how TCAS/ACAS has developed. There was a smiley.

[Learner_Driver]

About three years ago I was privileged to be on the jump seat of a medium sized airliner. A light aircraft was at the holding point.
We received 'Traffic Traffic' when at a low altitude on a visual approach to a pretty short runway, which was rather distracting to the crew.
Until that point, I had always switched on my transponder (with ALT) before taxy, but now wait until lining up (I operate at an airfield with numerous diverse types, from B747 to, well, my size of aircraft ).

[Dave Phillips]

..... and if you try to do that at a number of airports you will not even get a taxi clearance. ACAS II/TCAS II, which has been mandatory for EASA aircraft (5700kg+/19+ seats) registered since 2012 and legacy aircraft since 2015. ACAS II, inhibits nusance traffic alerts from aircraft on the ground. Read the previous link.

https://www.eurocontrol.int/sites/defau ... -guide.pdf

[rikur_]

So far in the poll 9 people sometimes forget?, I'm quite surprised at that.

surprised it's not greater?
I've not forgotten in recent times as nowadays it's just part of switching everything on, setting QNH, resetting G meter etc .... but I have overlooked it in the past, in part because at the time I was trained to set it whilst lining up, but also in part because typically when flying with someone else they deal with the transponder, and then one day you fly with someone who doesn't. (And before anyone feels the need to point out it's the P1s responsibility, I know)

[Neil MacG]

I'll openly admit that I am one of the ones who often forgets to put my transponder on Alt until some time into my flight. I think I understand why this is and there are 2 reasons...

1. During my training I was taught by my instructor Never to put the transponder to Alt until I was out of the circuit (I think this may have been due to local agreements)
2. When I finished my training I only flew for many years in an aircraft which did not have a transponder fitted (an Auster).

So I guess I never had this ingrained into me to turn the thing on. I try and remember to put the transponder to Alt when I leave the circuit but given I fly from a farm strip, and don't need to speak to anyone when I just out for a local flight I don't get given a squawk. However when I am flying towards or near airspace which has a listening squawk, I do make a point of using it.

[Waveflyer]

I try and remember to put the transponder to Alt when I leave the circuit but given I fly from a farm strip, and don't need to speak to anyone when I just out for a local flight I don't get given a squawk. However when I am flying towards or near airspace which has a listening squawk, I do make a point of using it.

If you are flying from a strip, why not leave it on ALT all of the time?

[Dave W]

Neil, that's just the reason why I trained myself a while ago to do line-up checks, which are now habit.

But I need to retrain again, because I reckon I prefer the 'SPLIT' mnemonic that @MarkOlding mentioned earlier in the thread.

The other thing I've learned today is to put the xpdr to ALT at startup, which I previously left until lineup.

[GolfHotel]

That check list could get me a blocking at certain airports I fly from - in particular where heavy metal is landing. If you switch on your transponder to ALT whilst parallel to the runway doing your run-up checks and a TCAS equipped jet is landing, you will cause a TCAS alert to be given which means paperwork....

For that reason they demand, especially if CAT is on final, that the transponder is only switched ON / ALT when you line up on the runway.

Name the airports because the TCAS assertion is absolute tosh. Many 'heavy metal' airports I fly from won't even let you push off stand if the transponder is off/sby.

I had landed at Cardiff and an A320 landed behind me. The pilot said he had a TCAS alert on final. ATC asked me if I had turned off my transponder.

The A320 still landed but he was clearly miffed.
I was puzzled as my transponder is supposed to turn its self to standby on the ground. But there is no change to the display so you don't know for sure.

[GonzoEGLL]

There's no guarantee it was your transponder that provoked this. There used to be a factory chimney a few miles W of LHR that would provide regular TAs to departures on Westerlies.