On Tuesday, April 17, 2018 at 12:18:55 PM UTC-4, bumper wrote:
On Tuesday, April 17, 2018 at 5:31:17 AM UTC-7, AS wrote:
On Tuesday, April 17, 2018 at 2:39:09 AM UTC-4, bumper wrote:
Not what you are after, but less drag. Can be special ordered with a threaded hole instead of mounting studs, no additional. This allows mounting with brass threaded rod with filed notch for breakaway if on belly.

http://www.deltapopaviation.com/Ultr...r_Antenna.html

bumper


.... but less drag.
Careful here. If you install this type of antenna on the fuselage off the centerline in an area where the fuselage is necking down and you don't know the exact flow conditions in this spot, you may have it sitting slightly sideways.
Not exactly comparable to a glider but to show what I mean, take a look at his kind of antenna mounted to the belly of power planes. One side is typically black from the exhaust and oil coming from the engine due to the spiraling prop-wash airflow. The airflow is not parallel to the centerline at this spot and the paddle antenna will create a bit more drag.

Uli
'AS'

Watch this short old video comparing drag of various shapes - from a drag perspective, you can't do much worse than round except maybe a flat plate!

https://www.youtube.com/watch?v=ftq8jTQ8ANE

bumper

Thanks for the link, Bumper! I even do have Asher Shapiro's book 'Shape and FLow' and am well aware of this ~10:1 ratio. All I am saying is that the advantage is reduced, if the flat antenna is not aligned properly with the flow.
I have the stick antenna installed and plan on 3D-printing a free moving, self-aligning airfoil for it. That should take care of the bad drag of the round wire.

Uli
'AS'