Worked on the installation of the Garmin GA-35 GPS WAAS & GPS/XM GA-57x antennas. Both units receive doubler plates & some builders have riveted the plates to the upper fuselage skin. To me, this seemed a bit overkill as there are four hefty bolts attaching each antenna to the fuselage. So, I thought I’d try reaching out to SteinAir to get their opinion regarding riveting the doubler plates to the fuselage. Luckily, Stein was working this Saturday & stated that it's optional & not really required. Great - I'll forgo that option for now as I can always come back to it if I find it to be necessary.
Under each doubler I elected to add a fabricated gasket. These are placed internally between the fuselage skin & the doubler. This thin layer of material should aid in dampening any vibration.
Interestingly, the GPS/XM GA-57x antenna has an external gasket, but the GA-35 GPS WAAS does not; or..., at least one was not included in the box. I’ll need to check on this.
