On Friday, January 6, 2017 at 12:20:26 PM UTC-8, Jonathan St. Cloud wrote:
I have a PowerFlarm and transponder. Ninety percent of my flying is from the Southern Cal operating areas up through the Sierras and typical operating area out of Minden. So while I do pass through a few more trafficked areas, (Cajon& Banning Pass, Tahoe, Reno...etc) the majority of my flight time is with other gliders. I perfectly see transponder equipped and Flarm equipped gliders, why would I want to add the capability of ADS-B out?

If I was regularly operating in LA class B airspace I can see why I would want all the help and broadcast, but for gliders not typically operating in high traffic airspace why the extra cost, space and battery drain?

You have what exact transponder in a experimental or certified glider?

As we've covered in two threads here recently, If you already have a Trig Transponder in an experimental glider then adding a Trig TN72 GPS is a relatively low cost way of getting 1090ES Out. That will make you visible to GA aircraft with ADS-B In (but you are already visible to them via TIS-B if you have a transponder, but you'll get a bit better ADS-B coverage and accuracy with ADS-B Out), make you visible over longer range to other PowerFLARM equipped gliders--potentially interesting to folks buddy flying. The fast/heavy jets with TCAS and ATC with SSR see you already via the transponder. ADS-B Out provides some improved tracking compared to SSR so in the case of an accident or landout may provide better position data to SAR organizations, but not great in the mountainous areas... and not a replacement for an InReach or Spot tracker.

ADS-B Out (including with a TN72 GPS on a Trig transponder) will trigger ground services to provide ADS-R and TIS-B service for your glider... which with PowerFLARM (which does 1090ES In only and is not compatible with ADS-R or TIS-B) that does you no good at all--but if you did want to play with a different ADS-B In receiver that might be intersting--but in reality is likely of no interesest to most glider pilots.