On Tue, 24 May 2005 12:10:16 +1000, you wrote: > At 09:32 AM 24/05/05 +1000, you wrote: >>Hi >> >>I was just looking over the BGA pages and came across a mention of FLARM >>(see http://www.flarm.com/index_en.html) >> >> Flarm warns against aircrafts and obstacles. >> >> The small-size, low-cost, low-power device FLARM broadcasts its own >> position and speed vector (as obtained with an integrated GPS) over >> a license-free ISM band radio transmission. At the same time it >> listens to other devices based on the same standard. Intelligent >> motion prediction algorithms predict short-term conflicts and warn >> the pilot accordingly by acoustical and visual means. FLARM >> incorporates a high-precision WAAS 16-channel GPS receiver and an >> integrated low-power radio transceiver. Static obstacles are >> included in FLARM's database. The collision warning algorithms were >> calibrated and optimized using thousands of flight logs. No warning >> is given if an aircraft does not pose an immediate threat. >> >>Is this compatible/comparable with the system here in Australia (whose >>name currently escapes me)? >> >>I also wonder when exactly a glider in the same thermal as you is deemed >>to 'pose an immediate threat'? >> >>-- >>Robert Hart [EMAIL PROTECTED] >>+61 (0)438 385 533 >>Brisbane, Australia http://www.hart.wattle.id.au > > > Interestingly the IGC has banned the use of FLARM in contests as it > breaches a rule that says you can't transmit data from one glider to another. > > ADSB would seem to have the same problem so a little re thinking by the IGC > would seem to be in order so that glider pilots could benefit from > collision protection. Glider pilots probably stand to benefit most from > this as enroute collisions between powered aircraft at Australian traffic > densities are extremely unlikely. Gliders tend to concentrate in the same air. > > FLARM was developed by the Swiss for use in the mountains where there are > likely to be lots of head on conflict cases developing. Don't know how it > helps when you go around a corner of the mountain and suddenly get line of > sight on a rapidly closing glider. The signals won't go through the hill. > It will help avoiding things like power lines and transport cables which > can be a significant hazard in the mountains in Europe. As ADSB gives you a > GPS receiver it should be able to do the same thing. > > As for costs, last I heard ADSB fit was quoted at something like A$7000 per > aircraft just for the GPS/1090 transmitter. Allegedly Airservices are going > to subsidise this. If you believe that I've got a nice bridge for you. > > Mike
One of the main reasons that Air Services is interested in ADS-B is that if adopted Australia-wide, it will overcome the need to install a new set of very expensive secodary radar sets. (the present set is almost at the end of their life) ADS-B receivers on the ground are relatively cheap, thus allowing a wider coverage at much lower cost. The intention is that the cost saved is used to subsidise the aircraft installations. There is an incentive for Air Services to assist aircraft installations, as it gives much better coverage for ATC, and has the benefit (if the aircraft owner wants it) to provide direct collision avoidance between aircraft. AFAIK, it will only be mandatory to install the transmit half of the system. The receiver in an aircraft will be optional. FLARM is a good idea, but if not adopted by *all* aircraft, is only partially useful. John G. _______________________________________________ Aus-soaring mailing list [email protected] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring
