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Old November 19th 20, 03:23 AM posted to rec.aviation.soaring
Martin Gregorie[_6_]
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Default midair in Bay Area Nov 7

On Wed, 18 Nov 2020 18:44:11 -0800, Eric Greenwell wrote:

Martin Gregorie wrote on 11/18/2020 5:48 PM:
On Wed, 18 Nov 2020 17:00:53 -0800, Eric Greenwell wrote:

I also expect to see other Flarms while preflighting the glider before
flying, and before takeoff - no Flarms seen means I likely have a
problem and should determine what it is.

Is that a difference between FLARM and PowerFlarm?

I've never used Power FLARM, but I don't recall any FLARM showing
traffic when stationary: even waiting on the second winch queue I don't
recall the glider on the other cable showing as it launched nor a tow
taking off on the far side of the field. Or, for that matter, landing
gliders triggering it when I'm in the launch queue, so in front of and
100-200m to one side of the landing glider. Then again, none of these
should trigger an alarm since a collision is not possible in any of
these cases is a collision possible. OTOH, even a taxiing tug 2-300m
away can trigger an alarm while I'm rolling up to the launch point
after landing: very disconcerting it is too when it happens!

But really: do it at the annual; do it when you are getting the glider
ready for the 1st flight of the season. It's not that hard - write
yourself notes if you can't remember.

Couldn't agree more. I always used to do that and now its a mandatory
item on the BGA-approved Annuals check-list.

I also like to run an early flight from a new season through the FLARM
trace analyser to check the range in all directions and make sure its
working correctly and the antenna didn't get displaced during the last
Annual.


I tend to use Flarm interchangeably with PowerFlarm, but as a US pilot,
PowerFlarm is what I have, and it does show the position of any
PowerFlarm equipped glider within range, even if both gliders are
stationary on the ground. It doesn't generate collision alarms it that
situation.


I should have added that I'm not surprised: to a first approximation on a
gliding club field nothing with FLARM fitted moves unless its taking off,
landing or is a tug taxiing, so there's little or no benefit in a
stationery glider flagging up moving aircraft for its pilot.

OTOH I can see that it would be useful for a Power Flarm to do so,
especially one with ADS-B in since, on a field that is also used by
powered aircraft, it would be able to flag up most? all? aircraft
movements, especially those on approach while you're waiting at the hold
point.


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