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Loss of GPS navigation with G530W and other weirdness


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I have an M20J that I keep at KDVT in Phoenix, but my question is not necessarily Mooney-specific.  I keep the Jeppesen database up to date in my G530W, but everytime I fly over the Phoenix Class B airspace southbound over Squaw Peak I get a message the the GPS navigation is lost and to use another navigation source.  The moving map ceases to function for a few miles and then comes alive again.

I will occasionally ge the same message in other parts of AZ and CA, but I always get the message in the Phoenix Bravo.  Anyone have an idea what causes this?

 

The other G530W weirdness is I used to be able to see the class D airspace on Nav page one, but now I have to go to page two to see the Delta airspace.  What is up with that?

 

Any ideas would be appreciated.

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Have you read up on G antenna issues?

There are two that have come through over the years...

1) the manufacture of the antenna early on gave some problems over time.

2) the placement of two GPS antennae too close together cause interference issues.

You may have to combine these thoughts with whatever the specific location challenge is.

Then get in line to let loose your thoughts on SW updates from Big G...

1) one of us is having challenges with outdated data bases...

2) a few are having challenges with sharing data between boxes by other manufacturers. Works one day, then a SW update makes it not work the next.

3) then there are the GTN guys that are waiting for all the attributes to work properly

You may want to check which software updates and database updates you have and include them in your post...

If you have two GPSs, measure the distance between the antennae...

This is all second hand info. I have ancient BK stuff. Works the same way it did in 1994...

Best regards,

-a-

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!GPS 06/008 (KZAB A0002/15) ZAB NAV (WSMR GPS 15-07) GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVAILABLE WITHIN A 499NM RADIUS CENTERED AT 332339N1063058W (TCS 070039) FL400-UNL DECREASING IN AREA WITH A DECREASE IN ALTITUDE DEFINED AS: 454NM RADIUS AT FL250, 385NM RADIUS AT 10000FT, 378NM RADIUS AT 4000FT AGL, 366NM RADIUS AT 50FT AGL 1506051830-1506052230

!GPS 06/001 ZAB NAV (WSMR GPS 15-07) GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVAILABLE WITHIN A 499NM RADIUS CENTERED AT 332339N1063058W (TCS 070039) FL400-UNL DECREASING IN AREA WITH A DECREASE IN ALTITUDE DEFINED AS: 454NM RADIUS AT FL250, 385NM RADIUS AT 10000FT, 378NM RADIUS AT 4000FT AGL, 366NM RADIUS AT 50FT AGL. DLY 0430-1330 1506040430-1506061330

!GPS 06/001 ZAB NAV (WSMR GPS 15-07) GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVAILABLE WITHIN A 499NM RADIUS CENTERED AT 332339N1063058W (TCS 070039) FL400-UNL DECREASING IN AREA WITH A DECREASE IN ALTITUDE DEFINED AS: 454NM RADIUS AT FL250, 385NM RADIUS AT 10000FT, 378NM RADIUS AT 4000FT AGL, 366NM RADIUS AT 50FT AGL. DLY 0430-1330 1506040430-1506061330

!GPS 06/013 (KZLA A1279/15) ZLA NAV (WSMR GPS 15-07) GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVAILABLE WITHIN A 499NM RADIUS CENTERED AT 332339N1063058W (TCS 070039) FL400-UNL DECREASING IN AREA WITH A DECREASE IN ALTITUDE DEFINED AS: 454NM RADIUS AT FL250, 385NM RADIUS AT 10000FT, 378NM RADIUS AT 4000FT AGL, 366NM RADIUS AT 50FT AGL 1506051830-1506052230

!GPS 05/105 ZLA NAV (CHLK GPS 15-07) GPS (INCLUDING WAAS, GBAS, AND ADSB) MAY NOT BE AVAILABLE WITHIN A 454NM RADIUS CENTERED AT 360822N1173846W (BTY 214059) FL400-UNL DECREASING IN AREA WITH A DECREASE IN ALTITUDE DEFINED AS: 430NM RADIUS AT FL250, 359NM RADIUS AT 10000FT, 301NM RADIUS AT 4000FT AGL, 251NM RADIUS AT 50FT AGL 1506041630-1506042230

These are why. It seems far away but it has stray signals across all of those areas.

Note: At 10,000 ft, it's 359-385 nm away and if your flying IFR across Arizona to California, you are above that where it extends even farther. These notams are very common around California, Arizona, and New Mexico and correct, some that I attached aren't valid now but they pop up frequently.

PS, the cool glasses smiley face are how the Notam is written out and then read by the message board. I didn't put them in.

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What are they turning on that does that?

Kinda puts some fear of going all GPS in the panel...

Best regards,

-a-

B)

Don't forget what all those "old pilots" used to say when GPS first became a thing.  "I wouldn't trust that because the government can turn it off and on at any time they want to."  Keep those old pilot skills fresh.  When was the last time we all flew VOR to VOR and switched at the change over point?  I know it's been a little bit for sure for me.

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What are they turning on that does that?

Kinda puts some fear of going all GPS in the panel...

Best regards,

-a-

B)

GPS is a relatively low power signal and isn't too difficult to jam... We used to do GPS jamming tests out at China lake when I was flying test out there both on our own GPS guided weapons as well as our aircraft and ground units. I imagine that the Navy and Air Force are still performing similar tests, hence the notams.

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Those GPS testing NOTAMs are not new, they've been doing this on and off for several years.  I'm in Colorado, but similar distance from the "epicenter" of the testing as folks in Phoenix.  No one I know around here has ever actually experienced a loss of GPS signal while flying during the advisory times.  In fact, I flew just this morning with no issues despite it being during the active test time.  Not saying it never happens, but my guess is the liklihood of signal loss on an aircraft GPS (or car GPS or phone or any of a bazillion other GPS-based devices on the ground within the affected surface area) is very low.  If signal loss was common, you can bet it would make the news.  Can you imagine the uproar if every iPhone in Albuquerque, Phoenix, Denver, etc. lost satellite nav?

 

Anyway, suspect that whatever issue the OP is having is not caused by the GPS testing.  I'm not privy to the testing, but my guess is the "jammer" is only turned up until test instrumentation shows the smallest measurable loss of signal/noise ratio, and then only briefly.  I'm pretty sure the NOTAM is in place to cover some unlikely but nonzero operator error.

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When was the last time we all flew VOR to VOR and switched at the change over point?  I know it's been a little bit for sure for me.

Why just last week. Victor airways from Little Rock, AR area all the way to Santa Monica and Monterey CA and back. Even had a Center controller try to give me a direct clearance shortcut. I responded I was slant Uniform and he asked if I had any GPS on board. I affirmed I had a yoke mount Garmin but told them I would stay on planned route.

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All,

 

Thanks for the input.

 

On the issue of the class Delta airspace "disappearance" from the #1 Nav page, all I had to do is click Ent twice and the Delta re-appears.

You were asking about de clutter and re clutter? Press the clear button to cycle through on the map page. I think there are 4 levels.

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Why just last week. Victor airways from Little Rock, AR area all the way to Santa Monica and Monterey CA and back. Even had a Center controller try to give me a direct clearance shortcut. I responded I was slant Uniform and he asked if I had any GPS on board. I affirmed I had a yoke mount Garmin but told them I would stay on planned route.

Nice!

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Don't forget what all those "old pilots" used to say when GPS first became a thing.  "I wouldn't trust that because the government can turn it off and on at any time they want to."  Keep those old pilot skills fresh.  When was the last time we all flew VOR to VOR and switched at the change over point?  I know it's been a little bit for sure for me.

 

 

Reminds me of what Boeing said when the Airbus A300 was introduced with ETOPS capability, that passengers wouldn't fly over open water on an airplane with just two engines. Now who is laughing?

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Reminds me of what Boeing said when the Airbus A300 was introduced with ETOPS capability, that passengers wouldn't fly over open water on an airplane with just two engines. Now who is laughing?

Very good point. I just sat behind a British Airways 747-400 yesterday for takeoff. Can't imagine how much gas he used just in the taxi. I wanted to know if the did 2 engine taxi because it looked like it was possible.

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Very good point. I just sat behind a British Airways 747-400 yesterday for takeoff. Can't imagine how much gas he used just in the taxi. I wanted to know if the did 2 engine taxi because it looked like it was possible.

 

I flew home from Heathrow last week on a British Airways 747-400 (seat 5A). He definitely didn't start all four until we were further up in the "queue" for the runway.

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I flew home from Heathrow last week on a British Airways 747-400 (seat 5A). He definitely didn't start all four until we were further up in the "queue" for the runway.

Well they save a fortune. I'm sure when the plane first came out that it was all 4 or they didn't move.

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