How to mount GPS antenna to fiberglass canopy?

[Auburntsts]

Originally Posted by DRMA

One thing to be aware of. When I talked to Van's technical support they said they do NOT recommend drilling any holes in the fiberglass cabin top that are not specified in the plans, as the fiberglass top is a structural member. So if you can mount the antenna below the cabin top, say inside the overhead console, without drilling any holes through the top, you should be ok. After a lot of reading and study, I came up with antenna arrangements that allow me to mount both GPS antennas, one Com antenna, and the ELT antenna all on the aluminum top skin behind the fiberglass cabin top, while still maintaining recommended spacing between antennas, ground planes, and distance from the vertical stab.

The second Com antenna is on the rear fuselage bottom, with the Xponder/ADS-B antenna forward in the tunnel but away from the gear legs.

Regards

I?m no engineer, and certainly don?t have any data to refrute Vans conservative recommendation, but I?m 100% confident that the two GPS antennas I have mounted to the top of my cabin and their associated holes have not significantly compromised the structure. Maybe I?m a fool and living on borrowed time so I guess ignorance is bliss. YMMV....

[DRMA]

Originally Posted by Auburntsts

I?m no engineer, and certainly don?t have any data to refrute Vans conservative recommendation, but I?m 100% confident that the two GPS antennas I have mounted to the top of my cabin and their associated holes have not significantly compromised the structure. Maybe I?m a fool and living on borrowed time so I guess ignorance is bliss. YMMV....

That?s why it?s called an experimental aircraft. We are each allowed to use our best judgement in building our planes. As a degreed and registered electrical engineer, I?m going to respect Van?s qualified aeronautical and structural engineering advice and not put any antenna on the outside of the fiberglass cabin top. Other builders are just as free to ignore that advise if they wish.

[ReidVaitor]

Originally Posted by sritchie

I'm definitely planning on mounting it INSIDE the cabin, hidden by the overhead console. I agree that velcro on the outside wouldn't be ideal

I guess if I didn't want to do that, a better idea would be to attach them with screws to the metal plates that screw in to the overhead console. I don't have anything mounted on those right now, and if I wanted to later I could introduce standoffs. Then the GPS antennae don't have to be upside down and I don't have to modify the cabin top at all.

Any thoughts on that approach?

yes, you're right on with this approach. I installed the Dynon GPS-250/2020 with 15lb double sided tape to the inside of the overhead console. Has worked for me flawlessly.

Pascal