Originally Posted by
The name is Porter
This is a serious situation. If the aircraft has been moved from the airfield, the aircraft's ADSB function has possibly been disabled, illegal.
I'm curious about whether it's actually illegal. CASA says:
9E.2 Subject to paragraph 9E.3, an aircraft:
(a) that is:
(i) first registered on or after 6 February 2014; or
(ii) modified by having its transponder installation replaced on or after
6 February 2014; and
(b) that is operated:
(i) in Class A, B, C or E airspace; or
(ii) above 10 000 feet above mean sea level in Class G airspace;
must carry a serviceable Mode S transponder that meets the standards:
(c) for Mode S transponder equipment — in subsection 9C; and
(d) for ADS-B transmission — in a clause or clauses of Appendix XI as follows:
(i) clauses 2 and 5 of Part B; or
(ii) clause 7 of Part C; or
(iii) clause 8 of Part C.
Note The requirement is for aircraft to be fitted with a Mode S transponder with ADS-B OUT
capability. That does not mean that ADS-B OUT transmission is also required under this paragraph. It
means that, with the later connection of compatible GNSS position source equipment, ADS-B OUT can
be transmitted as well as Mode S SSR responses.
Seems to me that if you stay in Class G airspace, you're absolutely fine to go without a Mode S transponder (or, for that matter, any transponder). Even if you're in Class A, B, C, or E airspace, you don't have to transmit ADS-B OUT messages. As far as I can tell, simply failing to turn on the GPS receiver will neatly eliminate any ADS-B tracking by disabling your position output; ATC will still be able to track you just like they always have done with Mode-C transponders. I can't actually see anything that requires the transponder to be turned on (you just have to carry it), although I suspect that CASA would not be amused if you flew into Sydney with a brand new Mode-S transponder (still in its box) on the back seat.