When showing PAW contacts on SK-De, some are swept wing jets, and some are straight wing ‘prop’ aircraft symbols. But the aircraft itself may be a jet in both cases.

Do these symbols mean anything particular? Will there be any more symbols, for microlights, gliders and helicopters etc? I see that Flightradar24 already shows many different types.

Tx

I believe the trajectory lines only appear for targets at approximately the same altitude as you. There's no point displaying them for other traffic.

SkyDemon uses TCAS-like conflict detection algorithms. An urgency situation is measured in terms of the number of seconds before a conflict is likely. Like TCAS, this is not a fixed number but variable depending on the nature of the closing situation, but will be between 30 and 60 seconds.