dead reckoning on 530/430

[glyn ferrell]

For the first time in over 2 yrs both the 430/530W showed "dead reckoning". After 10 mins they resumed navigation but 10 mins. later both showed "dead reckoning" again. After apprx. 10 mins. they both resumed navigation and continued working until I landed 1 hr. later. What is even more confusing to me is I also have a 496 and it went out and followed the pattern on the 430/530 and as I was landed "only" the 530 showed "Loss of intergrity" while the 430 and 496 continued working.....Anyone with similar experiences or thoughts???? I greatly appreciate input...

 

[EdFred]

Probably GPS outage or signal interruption if you had 2 separate units (and antenna) fail. Where were you and at what time?

 

[glyn ferrell]

flying from Tuscaloosa, Ala to Cape Girardeau, Mo (southeast Mo.)...it was between 11.30 to 1.30 this afternoon...thanks for your reply

 

[John Collins]

For the first time in over 2 yrs both the 430/530W showed "dead reckoning". After 10 mins they resumed navigation but 10 mins. later both showed "dead reckoning" again. After apprx. 10 mins. they both resumed navigation and continued working until I landed 1 hr. later. What is even more confusing to me is I also have a 496 and it went out and followed the pattern on the 430/530 and as I was landed "only" the 530 showed "Loss of intergrity" while the 430 and 496 continued working.....Anyone with similar experiences or thoughts???? I greatly appreciate input...

Glyn,

I have seen many reports of the same sort of issue on the W versions. They seem to fall into two categories, first one is transmitting on a VHF frequency that interferes with the GPS, and the other is a bad WAAS GPS antenna that goes into oscillation and jams any nearby GPS. The former can be fixed with VHF or ELT antenna position, inserting a notch filter in the VHF coax line near the VHF transmitter, replacing the coax on the VHF transmitter, or a combination of these. The latter is fixed by replacing the offending WAAS GPS antenna.

Next time, monitor the satellite page and note any loss of all satellites when you transmit. This points to a VHF interference issue. If this doesn't seem to be your problem, turn one of the W's off to see if the other comes back to life, if this can be repeated with predictable results, it points to a bad WAAS GPS antenna.

From your symptoms, I think you have one or two bad WAAS GPS antennas.

 

[Baron2PG]

For the first time in over 2 yrs both the 430/530W showed "dead reckoning". After 10 mins they resumed navigation but 10 mins. later both showed "dead reckoning" again. After apprx. 10 mins. they both resumed navigation and continued working until I landed 1 hr. later. What is even more confusing to me is I also have a 496 and it went out and followed the pattern on the 430/530 and as I was landed "only" the 530 showed "Loss of intergrity" while the 430 and 496 continued working.....Anyone with similar experiences or thoughts???? I greatly appreciate input...

It is your GNS530 antenna. I had the same issue about a year ago. The GPS signal would fade in and out and my hand held would also loose reception. Finally it fades to the point the GPS drops out and about 10 minutes later it will come back. The easy test is to put the GPS signal strength screen up on your hand held and the GNS530. Watch the signal strength. It will fade on both units. Turn off the GNS530 and your hand held will pop right up.

Quick easy fix; couple hundred bucks for the antenna.

 

[glyn ferrell]

Glyn,

I have seen many reports of the same sort of issue on the W versions. They seem to fall into two categories, first one is transmitting on a VHF frequency that interferes with the GPS, and the other is a bad WAAS GPS antenna that goes into oscillation and jams any nearby GPS. The former can be fixed with VHF or ELT antenna position, inserting a notch filter in the VHF coax line near the VHF transmitter, replacing the coax on the VHF transmitter, or a combination of these. The latter is fixed by replacing the offending WAAS GPS antenna.

Next time, monitor the satellite page and note any loss of all satellites when you transmit. This points to a VHF interference issue. If this doesn't seem to be your problem, turn one of the W's off to see if the other comes back to life, if this can be repeated with predictable results, it points to a bad WAAS GPS antenna.

From your symptoms, I think you have one or two bad WAAS GPS antennas.

John, thks for your insight. I spoke to the avionic shop that install them a couple of years ago and explain my trouble. He shared with me he had never heard of this happening before but he quickly said he was going to call Garmin and get their thoughts. He called back in less than 5 mins. asking me to bring the plane to his shop. Garmin told him the 530 antenna needs to be replaced. They felt it was oscillating and causing the problem. They also shared with him if it happens during the flight to his shop to immediately turn off the units and bring one back on (the 430). Will keep you updated and will share your thought with the avionic shop....glyn

 

[glyn ferrell]

It is your GNS530 antenna. I had the same issue about a year ago. The GPS signal would fade in and out and my hand held would also loose reception. Finally it fades to the point the GPS drops out and about 10 minutes later it will come back. The easy test is to put the GPS signal strength screen up on your hand held and the GNS530. Watch the signal strength. It will fade on both units. Turn off the GNS530 and your hand held will pop right up.

Quick easy fix; couple hundred bucks for the antenna.

Baron2pg please look at the reply I gave John. Will keep you both up to speed on this...

 

[stickhog]

Bit late to this thread, but glad I found it...thought I was going bonkers. I am flying a helicopter with 2 430's with WAAS antennas. I will list the following symptoms, actions taken and results. Hopefully someone has some help.
1. When they decide to, both 430's go "DEAD RECKONING". This happens about 15% of operations.
2. On multi-leg flights, DR might occur on 2d or 3d legs but not the first.
3. Checking satellite signals during DR occurrence reveals all signals are absent, upper right message says "ACQUIRING" but signal is never acquired in flight regardless of how long you wait
4. Even though 430's indicate "DEAD RECKONING" menu fields to the right of the screens indicate some accurate aircraft movement if a waypoint and Direct To were selected before failure.
5. Turning off the 430's and then turning them on in any combination of On & Off has no positive effect on the problem.
6. Satellite signals usually return 60-75 seconds after landing and accurate position is revealed. However, position and satellite signals are lost very quickly on a subsequent takeoff (the helo has not been shut down). This problem seems to be related to aircraft movement.
7. One antenna was changed but that did not fix the problem. We are now going to replace both antennas.
8. Garmin Tech Support was contacted and tried to help but troubles have continued.

Anyone else figured out the solution(s)?

 

[taters]

Isnt there a "refresh" they can do. I know I have had it done on a 496 (hold down on out button when turning on) and I swear on a 430 at one time. The thing (430) refused to pick up a signal. A garmin service center "refreshed" something and then it was fine....lots more satellites were showing up as well.