I run 1 down the center line of the plane 1 out the wing or 1 strait down or up and 1 down the wing its best to go with the mfg. specs they are not all the same,hope that helps
I think it is worth mentioning that HobbyKing sells replacement antennas for the FrSky receivers, one which is about 10" long, which is great for getting it away from things like the FPV transmitter and ESC. I put one of these on a flying wing with correct orientation and I get considerably better range than I used to.
Not a dumb question at all! In fact it's a very good question, you really can't install the antenna incorrectly. However that said there really is an optimal way to install it. Whenever you have a receiver that has more than one antenna, you are working with a diversity system. What that means is that your receiver is comparing the received signal strength from both antennas and is choosing the stronger signal to work with. Keeping this fact in mind the best way to install your antennas is with one parallel to the direction of flight (forward) and one at either a right angle parallel to the wing or at a right angle perpendicular to the fuselage. The reason for doing this is that antennas have something referred to as polarization. When you roll a plane 90 degrees and pitch up 90 degrees the received signal strength of the antennas will flip. In other words where one was previously horizontal it is now vertical, and vice versa. This change in orientation produces a dramatic change in the received signal strength via each antenna. A conversation about antenna orientation would not be complete without talking about the transmitter antenna. On a typical 2.4 GHz system the best radiation pattern for you transmitter antenna will be with the antenna in a vertical position perpendicular to the ground. This combined with a optimal installation of your receiver antennas will give you the greatest range possible from your system as well as giving you the most reliable signal possible.
Thank you Nathaniel for such clear and good explanation!