Originally Posted by
SCPL_1988
Spektrum,
Thanks, its a sad reality that anyone and everyone who discusses or provides
an intelligent analysis of an accident results in getting personal attacks
from those who rarely post anything intelligent but 2 or 3 line inordinary posts.
FACTS
A-DSB signals for the C-130 were in this case continuous.
There is no evidence of "patchy" or "unreliable signals" involving this C-130.
Most A-DSB signals above 10,000 feet can be seen continuously across most continents.
Even at 6,000 feet, A-DSB is seen continuously over most of Australian flight routes.
......Yes, this accident happened "miles away" but 1090 Mhz Signals go a very long way at 6,000 feet and
odds are it could be seen as far afield as Albury, Canberra and Sydney let alone
the hundreds of private receivers who feed data into the system.
.
I have to take you to task with your "facts" as they are not facts. You post smacks of a lack of knowledge of RF and the Australian terrain. An aircraft at a reported altitude of 6000ft is not 6000ft above ground level, which is the scenario you base your facts on. In this case at 6000 ft the aircraft was probably at best 1000 ft above most of the terrain and 1000ft BELOW the hightest terrain in the snowy area. As such, the footprint of microwave signals would be very limited indeed , likely sub 100km. As a former air traffic controller I can assure you sub 10000ft coverage at VHF is very unreliable in that area (it was part of my sector) let alone at microwave frequencies. There may well have been an enthusiast nearby who had coverage but I would prefer to wait for the official details to come out before any analysis of data is made.