On Friday, May 29, 2015 at 4:35:14 PM UTC-7, Lucas wrote:

Your note doesn't solve the basic problem: you cannot "predict" where the pilot will go in 10-20-... seconds.
Therefore any "prediction" is not possible.
This is very simple: there is no way of predicting what the pilot will do in most situations.
As already wrote, it's enough to look at a flight trace.
And, pardon me, but I have been working on flight dynamics for 19 years now. I don't know about you, but the background seems quite different at this point.

Experience: NASA Ames Research Center.

It is at best an academic argument and at worst a dangerous one to say that because you can't predict with 100% certainty that the pilot won't make an aggressive control input that it is pointless or ("impossible") to project forward a flight path for 15 seconds.

If the pilot makes aggressive control inputs any prediction of future position will change, and the old prediction will no longer be accurate. However, that does not make any attempt to predict future position useless. Most control inputs over a 15 second time period when thermalling or when cruising do not so alter the trajectory as to make a path estimate irrelevant. Generally the trajectory is pretty predictable. It's actually pretty hard to make a material change in your position in a thermal and it takes a while for it to evolve. Even if there is an aggressive control input the algorithm adjusts to include the change. If you maneuver and become a collision threat FLARM generates a warning, if you don't become a collision threat it doesn't.

Works pretty well for me.

9B