I agree entirely on the issues associated with FLARM antennas. I have installed several FLARM systems in our club aircraft and the antenna installation is a serious issue.

I think it is important to point out that the range tool has some very serious flaws and that relying on it to evaluate your antenna installation for range may give you a very false sense of how far you can adequately rely on it. The range tool reports average range at a variety of angles around the ship. In this kind of stochastic process, the average really doesn't mean anything. You have two targets whirling around in clear space whose sensitivity varies strongly with direction and the range tool uses measured contacts to estimate the range. In reality the actual range a contact can be made can vary quite widely. If the range tool displayed the estimated range (average) as well as the average plus and minus one standard deviation (three contours), you would find that in reality you have a very high statistical probability of not making contact unless you are very close. In addition, the way the tool is setup, where you can only enter a single flight, it is not possible to get enough contacts to even make this measurement. It probably takes an entire season of flying to properly determine this. I wrote some code to splice together lots of flight logs to do a better statistical analysis and the results are quite interesting.


Mark