Peter wrote:
That just goes through the logs to see how far out you picked up other traffic.
This at least gives you an upper bound for your potential range: If you never have “seen” a target that was further away than 5 km it is highly unlikely that there just never has been traffic at that distance ;-)
It is much harder to estimate dependability: From the log data you obviously only get the traffic you see and not the traffic you don’t see.
Therefore to get an estimate on dependability you would need a robust model of a) how much traffic you would expect at each range and b) how much of this traffic you would expect to carry a FLARM – pretty hard to estimate
Exactly; it is almost useless. The upper bound will be the combination of
For my TAS605 it would always return 15nm 
The issue here is not as much as which system is the best, but how do we get everyone to use a system that is good enough.
Using an analogy:
VHS won because it had more users, so more content was produced for it, which then made more people use it etc.., It also then became better over time as more was invested in developing the system.
Personally, I whish for universal adoption of ADS-B in / out for everything that is capable of flight above 400ft, with a low cost / low power option for those who do not have electrics.
But I would settle for FLARM if it were carried by everyone, in the same way that I settled for VHS because I could actually get content.
Disagree with your analogy!
VHS won because its features were a better fit for what end customers really needed.
Betamax in the beginning had exactly the FLARM issue we see today: Range was too low for many practical applications. They started with 30 and 65 Min Cassettes (as were known from audio tapes). That is great for individual episodes of your favorite TV show, but you could not record a movie on one cassette – and it took a long while for Sony to come ups with a 2hr solution. On the other hand, the better quality of Betamax was a nice feature – but the vast majority of TVs were not able to show this quality anyways.
Therefore VHS won because it had the superior features for the majority of the people that wanted it.
The Problem in aviation is, that our requirements are much more diverse than the requirements of a VCR-user: Doesn’t matter if you are a SciFi or Western Fan – you always need about 2 hrs of recording time. (Only very few people really only watch TV shows).
The requirements for a traffic system, however, are very different between different pilots and missions and therefore there is not one answer.
I think ADS-B is good in a way that many modern aircraft produced today might not have a full TAS but usually have ADS-B IN/OUT. And they won’t typically buy FLARM.
Therefore, if you want to be seen by them, you need Mode-S (ES) ADS-B out, which is not a problem for installation today.
And if you want to see them, then you need any ADS-B IN, which could be a feature of your avionics or PAW or FLARM or a tablet/laptop + SDR stick.
FLARM might be OK for gliders but for me the case for normal a/c is very artifical.
And how does it compare cost-wise with PAW?
Peter wrote:
That just goes through the logs to see how far out you picked up other traffic.
And how is that different from the range? The range is per definition the upper bound and not the average (or similar). Yes, it is influenced by the transmitter (installation), but the purpose is to see if your installation is ok. If you have ok range in most directions but e.g. close to nothing behind you, you know you have a problem.
mooney75 wrote:
And how is that different from the range?
Faulty logic.
If it says you picked up a particular target at range X, then that does not mean that everything at range <X was seen.
Malibuflyer wrote:
They feel safe when they put a portable device on there glareshield while they are still almost completely invisible from behind and hardly visible from the front.
We made a flight test of a portable FLARM unit in my club. The conclusion was that it was worthless in a metal aircraft. Even targets 2-3 km away appeared and disappeared as you banked the aircraft. That is not to say that it wouldn’t work well in a permanent installation with external antennas.
mooney75 wrote:
We recently upgraded to the ATD-80. You can see a picture of it here:
Can you comment on the differences between the ATD-80 and the LXNAV TrafficView 80?
Graham wrote:
If it says you picked up a particular target at range X, then that does not mean that everything at range <X was seen.
That is also not what “range” means. But this discussion is a bit meaningless. Most of the over 40,000 users of FLARM are happy with it having saved their life (at least that is what many people say).
