Mounting GPS WAAS Antenna on Glareshield?

[glafaille]

I realize that most Mooneys have a small glareshield.  However if the glareshield was expansive, is there a reason why a GPS WAAS antenna could not be mounted there?  Seems like it would make for an inexpensive install.

[kortopates]

Perhaps for a VFR installation you could mount it anywhere you wanted since it does not need to meet Garmin's installation requirements, but for the installation to be approved for IFR use (navigation and approaches)  it has to be installed in accordance with Garmin's installation manual guidance. Otherwise you'll likely have it labeled "For VFR use only" 

Edited February 21, 2017 by kortopates

[glafaille]

Thanks for the info.  I've been researching ADS-B out.  My current legacy IFR legal non WAAS GPS antenna is mounted on the top of my fuselage.  I've read that a GPS antenna should be mounted at least 2 feet from any other GPS antenna.  If I add an all in one ADS-B solution like a Stratus ESG, there is not a suitable location anywhere on top of the fuselage that is 2 ft away from the other antenna.

I do have a large glaresheld on my Grumman Tiger.  I'm trying to find out if that location will work.  It seems the glareshield is a popular mounting location for the experimental crowd.  I'm wondering if it will legally work for me.

[kortopates]

You'll have to talk to an avionics installer. Technically only an authorized Garmin dealer can perform an approved installation of a certified aircraft. (Garmin does provide the installation manual and approval for experimental aircraft.) But I wouldn't be worried about the 2 foot distance limitation. GPS WAAS antenna's are installed much closer than that routinely. I have 3 within a 2' patch on the roof. Plus the glareshield is something that suffers from frequently being removed as well as being shadowed by the fuselage behind you - which I think is the real problem. Satellite signals are extremely weak signals to begin so you really want them installed with the clearest view of the sky possible to get the best reception you can. Its no fun when you box gives you a LOI error from not having enough satellites in view and essentially shuts down till its gets enough signal again. 

Edited February 21, 2017 by kortopates

[carusoam]

With a sliding canopy you may have a location internally that may work...?

Best regards,

-a-

[StevenL757]

This doc was provided by my installer via Garmin prior to my recent cockpit re-do.  We added a GA36 and a GA37 in fairly-close proximity, and no issues reported in the last 9 months and over 120 hours' flying mainly IFR with multiple ILS and WAAS approaches.  Your mileage may vary...

Page 2-1 and onward will give you the guidance you're looking for.

Steve

GA35GPS_WAAS-antenna_AntennaInstall.pdfFetching info...

[glafaille]

Thanks Steven!  

Just the info I was looking for.  Looks like I won't have anything to worry about and can mount 2 GPS antennas relatively close to each other.  Glare shield mounting is no longer a consideration.  Problem solved.

Mooneyspace is the best!

[Piloto]

When I had the Aera 560 in my plane I located the XM weather antenna underneath the plastic glare shield with a home made bracket. It works very well in any heading. For weather now I have the Garmin Pilot WX and NOAA Aviation WX thru the internet on my Samsung S7 cell phone.

José

[glafaille]

If I could legally install a WAAS GPS antenna for my ADS-B install like that, it would cut the install price by at least 1/2.  Might be worth further research.