I started working on my IFR ticket in my RV-9A. I've noticed two things...
1) My KLN-89B gives me frequent RAIM warnings while shooting GPS approaches. I _think_ this is because I have my GPS antenna mounted under the cowling and when there are big changes in headings, it looses some satellites and has to recalculate. I intend to move the antenna either up to the glareshield or on the top of the fuselage that will hopefully correct this issue.
2) My Bob Archer NAV antenna isn't performing up to my standards. I have the wingtip antenna. I've shot a number of VOR approaches where the flags are wiggling like crazy trying to keep a signal and a couple of times have flagged all the way. In my opinion, I was close enough and high enough to receive sufficient signal. I think for normal VFR type stuff, this antenna is sufficient but I intend to switch to the Cat whiskers type antenna at my next annual.
Just something to consider for anyone still building and going the IFR route. I'll post my findings when I make my changes.
1) My KLN-89B gives me frequent RAIM warnings while shooting GPS approaches. I _think_ this is because I have my GPS antenna mounted under the cowling and when there are big changes in headings, it looses some satellites and has to recalculate. I intend to move the antenna either up to the glareshield or on the top of the fuselage that will hopefully correct this issue.
2) My Bob Archer NAV antenna isn't performing up to my standards. I have the wingtip antenna. I've shot a number of VOR approaches where the flags are wiggling like crazy trying to keep a signal and a couple of times have flagged all the way. In my opinion, I was close enough and high enough to receive sufficient signal. I think for normal VFR type stuff, this antenna is sufficient but I intend to switch to the Cat whiskers type antenna at my next annual.
Just something to consider for anyone still building and going the IFR route. I'll post my findings when I make my changes.
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