Cavalryman

Hello.

There is one EASA AD 2006-0265 about checking Mode "C" or Mode "S" transponders each 24 months.
Concerning small aviation: almost nobody performs it, almost nobody knows about it.
Could you, please, tell about your experience on this thing ? What is happening in MRO's maintaining small aircraft (Cessna 152's ; 172's ; small Pipers, Grummans, etc.)
Do I understand correctly, that if there is any kind of Encoder installed... AD 2006-0265 is applicable straight away ?

How much airplanes doesnt have "Mode "C" or "S" transponder" in Europe. Some guy told me, that almost every small AC is equipped with transponder with altitude input. If so, how the hell they are not performing this AD ?

wigglyamp

The AD applies to any transponder installation that uses grey code (also known as Gillham code) for the altitude source. We do the checks and I believe all other UK companies do comply. It's not difficult and should be done in any case of part of an annual avionics check to ensure transponder altitude accuracy.

camlobe

I concur with wigglyamp on this. Here in the UK, it has been a mandatory requirement for twelve years, initially as CAA AD 002-12-99, and then latterly as the EASA AD. I suspect that EASA AD 2006-0265 was proposed by the UK CAA and accepted in its entirety, hence the wording being the same.

camlobe

Keepitup

I can also confirm, here in the UK, we carry out this inspection regularly on our helicopters.

When you say almost nobody does it or nobody knows about it, are you referring to where you come from ?

Keepitup

Cavalryman

wigglyamp, camlobe, Keepitup,
thank You ! Now I can say, that this AD is well known and is being performed in Europe. You are right, this AD came to EASA from UK.

I am talking about my country only (somewhere in Eastern Europe). There is no equipment available for this check. I know, that somebody is going to get toolset from Finland to perform inspection in this country.

Interesting thing: there is no approved method mentioned in the AD. Theoretically, can maintenance depressurise pitot tubes (imitating flight at particular altitude) and ask some local dispatcher: "What altitude do you see?" ? Is it real, does anybody do so ?

P.S. Main question was about performance of this AD over the Europe. THanks again.

NutLoose

yup we do it too, our avioinics man puts a pitot static tester on to the altitude encoder then cross refers his pitot static test set reading with the other test set showing what the transponder is transmitting..