God bless TCAS
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“Dunno how that's gonna be resolved if S becomes compulsory...”
This was one of the things I looked into for the PFA. You can get some of the transponders direct from the manufacturer and do your own installation. A bigger problem is getting them tested, as some of the organizations would not test a home installation and mode S must be tested at regular intervals (at a cost). All to do with employee liability insurance, or that was the excuse given any way.
I put a second hand mode A in mine and am waiting to see what, if anything, we end up having to fit. I was going to go for a new solid state mode C, but if I had to scrap it in two years it would have been a crazy cost per hour.
Rod1
This was one of the things I looked into for the PFA. You can get some of the transponders direct from the manufacturer and do your own installation. A bigger problem is getting them tested, as some of the organizations would not test a home installation and mode S must be tested at regular intervals (at a cost). All to do with employee liability insurance, or that was the excuse given any way.
I put a second hand mode A in mine and am waiting to see what, if anything, we end up having to fit. I was going to go for a new solid state mode C, but if I had to scrap it in two years it would have been a crazy cost per hour.
Rod1
(b) If as much effort were put into R&D for Flarm reception by airliners etc. as is being funded for UAV's, Mode S, and other safety or airspace-capacity issues, no doubt Flarm detection range could be improved. There are none so deaf to the possibilities as those who don't want anything but their preconceived (and ill-conceived) part-solution.
There's a patent application from about 1998 with my name on it for a GA collision avoidance device that works just like Flarm. Somebody has written a letter in the last Flight Safety describing their CDTI invention. I'm sure there are many others, because the solution is obvious. Broadcast your position and receive the position of other aircraft.
I abandoned that application because it was pretty clear that the key issue in this area was one of interoperability and standardisation. It's no good to anyone if everyone is using different devices that don't talk to each other. And there were emerging standards -- I'd hoped that VDL Mode 4 would win, but the FAA threw it out early and at thaat point it was doomed. And the choice of protocol doesn't make much difference to the performance: the power consumption is determined by the range requirement, the cost is determined by the development and certification cost split across the market.
You can beef up Flarm to higher powers if you want, but all you have then is an incompatible device that draws the same power as a 1090ES ADS-B link of similar performance. Operating at the same power, there's nothing fundamentally more difficult about making a 1090ES datalink (that incidentally responds to Mode S interrogations) than Flarm. It's just a box of electronics.
The difference with 1090ES is that it will be carried by the vast majority of powered aircraft.
I'd hope that anyone developing a CDTI device based on 1090ES would learn from all the prior art, including Flarm, TCAS and the alleged failings of the somewhat rudimentary detectors currently on the market.
The LAST is a EUROCAE standard ED-115.
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Bw, I did not know - or had forgotten if I have seen it before - that the LAST is a EUROCAE standard ED-115; what does it mean - that a 20w or 30w LAST can now legally be used in Europe generally, and specifically in the UK? If not, what other steps does a regulation/specification/standard have to go through to enable people to voluntarily fit it (always assuming they can solve the certification and installation issues)? (I'm still trying to learn about these things.)
By the way, AIUI, Flarm is a de facto standard for gliders flying in the Alps, in certain competitions in some parts of the world, and there is an increasing take up elsewhere. I have not heard of any other approaches having anything like that take up rate.
Chris N
By the way, AIUI, Flarm is a de facto standard for gliders flying in the Alps, in certain competitions in some parts of the world, and there is an increasing take up elsewhere. I have not heard of any other approaches having anything like that take up rate.
Chris N
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According to the PFA the minimum output in accordance with international standards is 70w which is too much for a truly portable device. It is also expected that a 30w unit with an integral aerial sat on the passenger seat of a typical PFA type aircraft will be totally invisible in some directions, and almost so in others. There was a plan to test this as opposed to relying on the calculations but I am not sure how far this has got.
Rod1
Rod1
By the way, AIUI, Flarm is a de facto standard for gliders flying in the Alps, in certain competitions in some parts of the world, and there is an increasing take up elsewhere. I have not heard of any other approaches having anything like that take up rate.
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Bw, you can mention TCAS by all means. I would mention it, as in it's take up rate in gliders and light GA is nil. We can't fit it in gliders AFAIK, nor most other light GA, and it would have done nothing to help prevent glider/glider and glider/obstacle (e.g. cable) collisions in the Alps where Flarm started, whereas such collisions have now almost or entirely ceased. Flarm is now used also by rescue helicopters and maybe other things too. As posted by a friend of mine elsewhere (Bill Dean):
"Flarm is, Flarm to Flarm. Up to now it is mainly fitted to gliders,
practically universal in the European Alps, and widely fitted in Australia.
In the Swiss Alps it is also fitted to rescue helicopters, partly because of
its obstacle database.
"ADS-B out can be read by ADS-B in.
"In Australia they are working on the idea that an enhancement to ADS-B
could enable it to read Flarm, and an enhancement to Flarm could enable it
to read ADS-B.
"This is why things may improve when Mode A/C and Mode S are phased out in favour of ADS-B.
"In Australia Flarm is built under licence (OzFlarm), there are other
licensees. Is there nobody interested in doing this in the USA ? It
would surely be ideal for any light aircraft. I understand that there is
an add-on to Flarm which can sound a signal in headphones.
"Remember, Modes A/C and S are only transmitted when the Transponder is
triggered by an interrogation. Flarm and ADS-B transmit regularly without
having to be triggered."
(If any one is interested in Flarm, see http://www.flarm.net/index_en.html .)
Chris N.
"Flarm is, Flarm to Flarm. Up to now it is mainly fitted to gliders,
practically universal in the European Alps, and widely fitted in Australia.
In the Swiss Alps it is also fitted to rescue helicopters, partly because of
its obstacle database.
"ADS-B out can be read by ADS-B in.
"In Australia they are working on the idea that an enhancement to ADS-B
could enable it to read Flarm, and an enhancement to Flarm could enable it
to read ADS-B.
"This is why things may improve when Mode A/C and Mode S are phased out in favour of ADS-B.
"In Australia Flarm is built under licence (OzFlarm), there are other
licensees. Is there nobody interested in doing this in the USA ? It
would surely be ideal for any light aircraft. I understand that there is
an add-on to Flarm which can sound a signal in headphones.
"Remember, Modes A/C and S are only transmitted when the Transponder is
triggered by an interrogation. Flarm and ADS-B transmit regularly without
having to be triggered."
(If any one is interested in Flarm, see http://www.flarm.net/index_en.html .)
Chris N.
"In Australia they are working on the idea that an enhancement to ADS-B could enable it to read Flarm, and an enhancement to Flarm could enable it to read ADS-B.
"Remember, Modes A/C and S are only transmitted when the Transponder is triggered by an interrogation. Flarm and ADS-B transmit regularly without having to be triggered."
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[In Australia . . . . . an enhancement to Flarm could enable it to read ADS-B] Bw asked "That would be interesting. Are we talking 1090ES-based ADS-B? I presume so, since I think that's the Oz choice for ADS-B datalink."
Sorry, I don't know - it's going beyond my limited knowledge. . Dunno if a search of r.a.s. or a Google search would throw up a useful answer.
Chris N.
Sorry, I don't know - it's going beyond my limited knowledge. . Dunno if a search of r.a.s. or a Google search would throw up a useful answer.
Chris N.
Lots of good stuff on the Australian site:
http://astra.aero/ABIT/index.aspx
It's of note because the Oz implementation of ADS-B is over 1090ES, i.e. through Mode S transponders. (The FAA is also trialling UAT.)
The arguments are not the same as those for mandatory Mode S, and even as regards ADS-B the Oz safety arguments are different -- they've got a lot less complete radar cover, and it's expensive to provide. Nevertheless, there's some useful info in there.
http://astra.aero/ABIT/index.aspx
It's of note because the Oz implementation of ADS-B is over 1090ES, i.e. through Mode S transponders. (The FAA is also trialling UAT.)
The arguments are not the same as those for mandatory Mode S, and even as regards ADS-B the Oz safety arguments are different -- they've got a lot less complete radar cover, and it's expensive to provide. Nevertheless, there's some useful info in there.
