Andrzej Kobus wrote on 11/21/2020 10:53 AM:
On Saturday, November 21, 2020 at 8:54:55 AM UTC-5, Eric Greenwell wrote:
Andrzej Kobus wrote on 11/20/2020 5:57 PM:

The B antenna is not required for safety in my glider. My ASH26E has two antennas in the nose
(Flarm and ADSB), producing excellent range in most directions, and sufficient range to the
rear for collision avoidance. I tried a B antenna on the belly, and it did improve the range at
which I could detect other Flarm units, especially below. Since the unit already had sufficient
range in all directions, the B antenna did not improve it's collision avoidance ability, and I
removed it after 10 or so flights.

I think my experience would apply to almost any Schleicher glider - they all use essentially
the same fuselage, starting with the ASW24, which do not have carbon in the nose. That's a lot
of gliders.


Eric, you wish what you wrote to be a fact, but in reality you can not have 100% in a glider that uses carbon and has only one antenna. I used to own ASH-26E with Flarm and from experience know there are blind spots. One flight in a competition gaggle would prove it for you. You will not be seen by others all the time and you will not see others all the time on your Flarm if you and they have only 1 antenna.

The gaggles I've flown in did not expose those problems, perhaps because they have not been as
dense as the worst contest gaggles sometimes are. Did your 26E have the antennas mounted in the
nose? Where was the worst blind spot?

In general, I would expect the signal strength from nearby gliders (+/- 500'vertically, 1000'
horizontally) in a gaggle to overwhelm all but the very worst antenna placement.
--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1

My antenna was mounted in the nose and the worst coverage was to the back, above the glider, very dangerous blind spot. I then moved the antenna to the glare shield, improved the above the glider and worsened below the glider.. Blind spot below the glider was more acceptable to me.

Curious. The behind and above has never been a dead spot for me, meaning "while thermaling
gliders above and behind were always detected). No one has ever mentioned a problem seeing me
from that position, either.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1