There are a few “miscellaneous” antennas that need to be mounted somewhere. These are satellite antennas, so they’re small, but I didn’t want to mount them to the outside of the airplane, if possible. Other people put them on the glareshield (fancy airplane term for “dashboard”), but didn’t like that either. In the homebuilt world, another popular place is under the cowl. These satellite signals go through the paint and fiberglass just fine, and this location means they’re completely hidden, which is nice. I designed and built a shelf for these. It’s attached in the rear to the firewall using a piano hinge and in the front to the engine mount using an Adel clamp. The antennas here are:
- GPS antenna for Trutrak ADI (backup instrument)
- GPS antenna for Garmin 696 (large screen moving map)
- XM antenna for XM weather data and radio
Note the antenna for the “main” GPS, with will be used for IFR en route navigation and approaches, was installed on top of the fuselage, in accordance with the installation instructions. Though I’m sure this one would be fine below the cowl as well, I decided to do it by the book since it’s an “official” GPS.