On Tuesday, November 24, 2015 at 11:16:35 AM UTC-8, James Metcalfe wrote:
At 18:03 24 November 2015, Richard wrote:
... Really James, I suspect something is very wrong with your
Flarm. ...

Interesting thought. That would mean a fault in the Flarm
algorithms, or (highly improbable) a bad but operable installation of
the Flarm firmware. And, BTW, more than one Flarm unit was used
over those years.
J.

Since you've owned several I guess it's safe to say there's more benefit than downside.

I'd be hard pressed to say I've ever had a false alarm - I guess it depends on how you define such a thing. If you mean an alarm when there were no other gliders in the air I would definitely look at whether you need to replace the hardware or firmware. If you mean you got an alarm for a glider in the area that you didn't think was an immediate threat you might consider 'competition mode' which sets the collision parameters tighter before issuing an alarm. We all have our comfort zone, but I'd be dubious about reports of alarms where that projected flight paths of the gliders involved weren't crossing within the radius of error that the algorithm assumes. As you may recall, Flarm projects curving flight paths, so you don't need to be on a straight-line converging path to generate an alarm. In a busy thermal you'll get lots of alarms, but the flying is so dynamic that the threats can come and go with regularity. It's not so much a false alarm in that case, but a transient conflict and probably not super-helpful, but technology has its limits in the analog world.

If the OP is considering whether to equip with Flarm I'd say if you intend to fly with other gliders, get one and if the other gliders don't all have them already, organize a group purchase.

I've had lots of useful alarms. I'd wager at least one prevented me from taking the silk elevator home.

9B