Flarm Range Analysis

Both A & B antennae will be blocked by the engine and one or two bodies.

I'd look into placing the B antenna behind the gear in the tailcone.

On two Scout towplanes, I taped the dipole to a structural cross piece with
a
bit of balsa in between and connected to the A port. The B port got the
straight up antenna.

The problem is that the B antenna is receive only. So if the other guy is in you blind spot, he won't see you even if you can see him. A RF opaque glider needs at least two transmit antennas to get a full situational picture.

And as Mark points out, the range tool is a 2D projection of 3D data. So the good range shown could be based on a cone pointing up or down. It's possible your range is near zero on or near the horizon.

Maybe the range tool should provide several charts for different azimuths. But ti would still not be quite right because some hits would be while the glider is banked. So now the range tool should analyze the track and estimate bank angle.

Gets complicated pretty fast :-)

5Z

On Thursday, June 8, 2017 at 2:00:04 PM UTC-7, George Haeh wrote:
Both A & B antennae will be blocked by the engine and one or two bodies.

I'd look into placing the B antenna behind the gear in the tailcone.

On two Scout towplanes, I taped the dipole to a structural cross piece with
a
bit of balsa in between and connected to the A port. The B port got the
straight up antenna.

Understood.

Along those lines, I recall in my AF jet, the transponder had an antenna
select switch - Top, Auto, Bottom. That would be nice for the Flarm.

On 6/8/2017 10:40 PM, wrote:
The problem is that the B antenna is receive only. So if the other guy is in you blind spot, he won't see you even if you can see him. A RF opaque glider needs at least two transmit antennas to get a full situational picture.

And as Mark points out, the range tool is a 2D projection of 3D data. So the good range shown could be based on a cone pointing up or down. It's possible your range is near zero on or near the horizon.

Maybe the range tool should provide several charts for different azimuths. But ti would still not be quite right because some hits would be while the glider is banked. So now the range tool should analyze the track and estimate bank angle.

Gets complicated pretty fast :-)

5Z

On Thursday, June 8, 2017 at 2:00:04 PM UTC-7, George Haeh wrote:
Both A & B antennae will be blocked by the engine and one or two bodies.

I'd look into placing the B antenna behind the gear in the tailcone.

On two Scout towplanes, I taped the dipole to a structural cross piece with
a
bit of balsa in between and connected to the A port. The B port got the
straight up antenna.

--
Dan, 5J