Casey, a simple Mode C transponder makes you visible to TCAS equipped
aircraft which IIRC includes the Flying Doctor.
Nowadays in Australia you can't do that for a new install so you get
a Mode S transponder which is also Mode C capable and make sure you
get one that is ADSB ready. Then you only need the GPS.
Many people in the US have correctly identified the high cost
stumbling block to ADSB which is the need for the fancy certified
GPS unit. When an excellent GPS module (that's the whole shebang
ready to go. Excellent GPS chips like the uBlox LEA7 series are
around $17) costs at most a couple of hundred dollars people rightly
balk at shelling out $3000 to $5000 for the certified unit and that's
without the certified GPS antenna and installation. Particularly for
VFR aircraft. After all when did the GPS in your iPad , phone etc
last tell you lies? The exposure to the sky in an aircraft is
excellent so no urban canyon shielding, multipath etc.
The US has gone for 1090 Extended squitter for heavies to maintain
ICAO and international compatibility. The fear was that if this was
to equip all the light aircraft the whole system would be overloaded
and cease to work AT ALL. Hence UAT. for the rest of us this
unfortunately means that the world's largest market is oriented
towards expensive 1090 units or cheaper prolific UAT which doesn't do
us any good.
When ADSB was first mooted around 20 years ago there were IIRC 4
different rf links on the table. The Swedes had something called VDL
which I gather used a VHF frequency. With now 1440 VHF channels I'd
have thought you could dedicate TWO channels to collision avoidance
and have a comms radio with attached GPS which gave you voice comms
and a Flarm like data comm with range of many tens of nautical miles.
This whole thing is one giant bureaucratic charlie foxtrot.
Mike
At 04:09 PM 21/05/2015, you wrote:
I'm sorry Nigel but it's not superior at all, it's downright
dangerous. The adoption of UAT in the USA is a mistake. With UAT
based ADS-B, you are invisible to commercial aircraft! TCAS is
unable to see UAT. So Qantas Link, Rex, the RFDS etc can't see
you. ATC can but that is of minimal use to us. Datalinked weather
is a nice bit of window dressing but not at the expense of 76,000kg
of high-speed rolled sheet metal doing 300kts not being able to see me!
Case
iPad transmission
We should be pushing the UAT version of ADS-B, far superior to 1090
transponder technology and offers a full datalink capability so weather
warnings, ATC directions etc can be broadcasted. We only went down the road
of using 1090 here because a lot of the commercial aircraft were fitted with
mode S transponders and only needed to add an approved GPS source to go
ADS-B
_______________________________________________
Aus-soaring mailing list
[email protected]
To check or change subscription details, visit:
http://lists.internode.on.net/mailman/listinfo/aus-soaring
Borgelt Instruments - design & manufacture of quality soaring
instrumentation since 1978
www.borgeltinstruments.com
tel: 07 4635 5784 overseas: int+61-7-4635 5784
mob: 042835 5784 : int+61-42835 5784
P O Box 4607, Toowoomba East, QLD 4350, Australia
_______________________________________________
Aus-soaring mailing list
[email protected]
To check or change subscription details, visit:
http://lists.internode.on.net/mailman/listinfo/aus-soaring
