PowerFlarm at Region 9 Contest

On Monday, June 10, 2013 11:21:33 PM UTC-5, Dan Marotta wrote:
Yes, but you can't get out of the way of an airliner - you're a stationary

target at his speed. And, if you have a Flarm only and not a transponder,

the airliner won't see you.

In fact, powerflarm gives lots of warning about airliners. They have mode S, ADSB transponders, so you see exact position and altitude from many miles away.

Just last weekend I was looking at my clearnav display, wondering how I was picking up that glider 10+ miles away, then noticed it was above cloudbase and descending 20 knots. Oh, yeah. Hmm, better alter course a bit to the right.

That's not an argument against transponders. I fly with both flarm and transponder. Flarm gives glider to glider collision warnings, especially in contests and densely flown glider areas. Flarm lets you see adsb-equipped aircraft, with enough warning to get out of the way of anything flying subsonic..

Transponders lets the FAA and airliners avoid me. That's very important where I fly since Midway approach seems to love to blast airliners through 20 miles of congested class E airspace right over our club at 4000'. Choose which risk you face most, and cost/benefit.

Contests are verging to large scale voluntary flarm adoption. It's not clear to me that Dan understands this thread is mainly talking about contests. For most contests, flown away from lots of heavy traffic, one can make a case that a transponder is less cost effective, and flarm much more important..

I would imagine that other densely flown glider areas would want to start thinking about heavy flarm adoption too, say up and down the white mountains or the pennsylvania ridges. Operations with lots of glider traffic, so that midairs among pilots based out of the same airport are the prime threat, might consider flarm as well.

If you fly all by yourself in heavy power traffic areas, and you're cheap, then one can make a case for transponder and no flarm. Still, you don't see the other traffic.

John Cochrane