On Feb 16, 9:42 pm, "Mike Schumann"
wrote:
I find it difficult to believe that adding a battery would cost
$1,000. I
would think that this could be included as part of the installation
of the
transponder.

I hope I didn't scare anyone off, as I've heard of only one instance and
it was a certified glider. But, it is the kind of thing a few pilots
worry about.

Pilots with "newer" gliders will have factory locations for at least two
batteries; "older" gliders generally weren't so well equipped, so there
may be some effort and expense involved in adding another battery.

I suspect a more common problem than insufficient space for adequate
batteries is the battery getting low during the flight. This can happen
because the flight is much longer than usual, the battery(s) weren't
charged completely before takeoff, there was a battery or wiring
failure, or other problem. This is the main situation I tried to address
with the comments about using the transponder in the areas of greatest
risk, and turning it off elsewhere.

The point I was trying to make is that pilots that have just spent
~$2300 for a transponder, encoder, cabling, and antenna, plus looking at
some more for the installation, aren't going to balk at buying a $10 (or
even a $100 battery!) to power it. It's generally a much bigger amount
for the complete installation (at typical technician hourly rates in the
$50-$70 range) that makes the complete package to expensive for some pilots.

My "Guide" offers some ideas for dealing with the power issue, besides
the obvious one of adding another battery.


--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org