Transponderz

On 11/2/2012 4:55 PM, Dave Nadler wrote:


For this reason:
- aircraft in formation only have ONE aircraft's
transponder turned on
- aircraft approaching Oshkosh are required to turn
their transponders OFF (except Mode S)
- the rest of the world has effectively outlawed
Mode A/C in favor of Mode S.

Hope that's clear,
Best Regards, Dave

What to do is not at all clear to me. I've never been in a thermal that
decided to turn off some transponders, and I don't hear of any contests
where a protocol was put in place to achieve this. For example, how does
this statement "aircraft in formation only have ONE aircraft's
transponder turned on" apply in these situations; i.e., what constitutes
a "formation"?

- two gliders thermalling at the same altitude? Three? Four? Five?

- How about 10 gliders spread over two thousand feet of altitude? Should
only one have it's transponder on, or should the gliders at the top and
bottom have them on? Or one transponder every 1000'?

- Or two gliders cruising together: are they a formation if they are
100' apart? 500'? 1000'? Or if it's three gliders? Four?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)