Flying_Monkey
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Need some help here... Garmin 430W and 106A CDI seem to function properly when in GPS mode. The CDI seems to correspond to the 430w's magenta line.
I was shooting some practice VOR approaches as part of ifr training today. The 430w was in VLOC mode and I was tracking the inbound course on the appch. CFI and I both noticed that while the CDI kept saying I was left of course the 430w screen was showing me right of the course. The VOR approach was loaded into the 430w for situational awareness only. The appch controller told us we were a mile off course, but the CDI showed on course. The 430 screen as GPS reference only was showing us a mile off course. Then, it seemed like the 106a CDI swung back the other way, indicating a similar course and position as the 430w GPS. My nav 2 VOR (kx155) was agreeing with the 430w GPS as well. When the nav 1 106a swung back it was then aligned with the nav 2 and seemed to function properly.
On takeoff on the next flight the 106a needle seemed almost stuck for awhile. My instructor tapped it and it seemed to help but still felt like it was giving erroneous readings. Switching to GPS mode the needle seems to display the proper course and agrees with the 430w screen.
I have flown a lot with the 430w in GPS mode and the CDI seems to behave properly when in GPS mode. I have tracked some headings in obs mode through the LA special flight rules area using GPS mode and the CDI.
I have heard both navs use the same antenna so I am thinking it is not the antenna.
Anyone have any ideas how to start trouble shooting this? I'm trying to gather all info and do whatever tests I need to before taking it in. Thank you!
I was shooting some practice VOR approaches as part of ifr training today. The 430w was in VLOC mode and I was tracking the inbound course on the appch. CFI and I both noticed that while the CDI kept saying I was left of course the 430w screen was showing me right of the course. The VOR approach was loaded into the 430w for situational awareness only. The appch controller told us we were a mile off course, but the CDI showed on course. The 430 screen as GPS reference only was showing us a mile off course. Then, it seemed like the 106a CDI swung back the other way, indicating a similar course and position as the 430w GPS. My nav 2 VOR (kx155) was agreeing with the 430w GPS as well. When the nav 1 106a swung back it was then aligned with the nav 2 and seemed to function properly.
On takeoff on the next flight the 106a needle seemed almost stuck for awhile. My instructor tapped it and it seemed to help but still felt like it was giving erroneous readings. Switching to GPS mode the needle seems to display the proper course and agrees with the 430w screen.
I have flown a lot with the 430w in GPS mode and the CDI seems to behave properly when in GPS mode. I have tracked some headings in obs mode through the LA special flight rules area using GPS mode and the CDI.
I have heard both navs use the same antenna so I am thinking it is not the antenna.
Anyone have any ideas how to start trouble shooting this? I'm trying to gather all info and do whatever tests I need to before taking it in. Thank you!
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