Why Non-GPS Avionics are Still Necessary

Palmpilot

Palmpilot

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Richard Palm
Why you should have non-GPS navigation capability in your aircraft:

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https://www.faasafety.gov/files/notices/2018/Jan/NTC_18-01L_GPS_Flight_Advisory.pdf
 

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Sure, why not? ;)
 
I got the FAA email about this, and interestingly received a similar one in mid-November advising potential interference around Barstow over Thanksgiving week. I drove from San Francisco to Albuquerque for Thanksgiving (weather was too unsettled to fly the Zodiac), and the Garmin Nuvi GPS in my car went berserk going through Barstow both going to Albuquerque the Sunday before Thanksgiving and returning the following Sunday. For a half hour it was continuously spouting "recalculating, recalculating, recalculation" with the display going nuts.

I still have VOR. :)

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just fly less than 50'AGL and you'll be fine. sheeeit, no magenta line.....that's crazy talk.
 
Very common in NM, impacting AZ, east TX and CO. So what else is new?
 
when i set mine up, i do tend to think that instead of a gnc255 as nav/com 2, i'll keep a KX155 with glideslope and it's own indicator in there. they're not terribly expensive, and give you ILS and VOR as a backup to GPS and to the GNS navigator going out
 
Always good to have a second radio,with vor,ILS capability’s and a current chart.
 
MIFlyer said:
when i set mine up, i do tend to think that instead of a gnc255 as nav/com 2, i'll keep a KX155 with glideslope and it's own indicator in there. they're not terribly expensive, and give you ILS and VOR as a backup to GPS and to the GNS navigator going out
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The GNC255 has all those same capabilities (probably why marketing chose that model number), plus 8.33 frequency spacing. Street price was not that bad when I bought mine.
 
This reminds me of flying around central California with nothing more than a single VOR and a paper sectional. Line up a VOR radial crossing a railroad track and all was good.
 
catmandu said:
The GNC255 has all those same capabilities (probably why marketing chose that model number), plus 8.33 frequency spacing. Street price was not that bad when I bought mine.
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thanks. i am just learning, so that's good to know. What advantages does it have as nav/com 2 over an old kx155 with GS? (Obviously 8.33 frequency spacing and being 40 years newer... i think i'm answering my own question.) It gives you VOR/LOC/GPS plus ILS glide slope?

I guess if you had a plane with a serviceable kx155 as #2, would you bother to spend the coin on the GNC, or just keep it (assuming you were upgrading #1 to a moving map and were going to be "in there anyway"?
 
The MON system presumes you will have ILS capability for many years to come.
 
aterpster said:
The MON system presumes you will have ILS capability for many years to come.
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That is what I was thinking also. The FAA is using the MON for GPS backup. The biggest problem I see is that an ILS capable airport is (as I understand it) supposed to be within 100 miles. That could easily stretch fuel for some of us.
 
MIFlyer said:
thanks. i am just learning, so that's good to know. What advantages does it have as nav/com 2 over an old kx155 with GS? (Obviously 8.33 frequency spacing and being 40 years newer... i think i'm answering my own question.) It gives you VOR/LOC/GPS plus ILS glide slope?
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No glide slope, just a CDI.


MIFlyer said:
I guess if you had a plane with a serviceable kx155 as #2, would you bother to spend the coin on the GNC, or just keep it (assuming you were upgrading #1 to a moving map and were going to be "in there anyway"?
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When we put a 430W in the Arrow, we kept the better of the two already installed -155's as #2, made the most sense.

Later, my RV had a single KX125 when I decided to redo things. My goals were reliability (only certified IFR source), dual frequency capable, and simplicity. In that case, the -255 fit the bill: Solid state technology, monitor function for dual frequency, and integrated intercom, further simplifying the panel design. It was not perfect though, my plan to shoot an ILS nearby and then scoot home to my field at 1k' AGL failed on my very first IMC trip: while doable according to observations at the two airfields, there was a 400' ceiling in between the two. This weekend I am installing a GPS400 so I can just fly the approach at my home field (picked that as the buttonolgy matches the 430W in the Arrow).
 
somorris said:
That is what I was thinking also. The FAA is using the MON for GPS backup. The biggest problem I see is that an ILS capable airport is (as I understand it) supposed to be within 100 miles. That could easily stretch fuel for some of us.
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True enough. But, the loss of GPS will constitute an emergency. If VFR remain VFR if able and land at a closer suitable airport. With ADS-B ATC should be able to assist just about everywhere.
 
They've had a quite a few GPS outages in that spot over the past 12 months. I know they're doing some drills on non-GPS guidance systems for the military. I know they're bringing back celestial navigation for the Navy guys. Wonder if they'll do the same for tankers and bombers...
 
Not sure what the big deal, they are conducting interference testing (so they are on purpose monkeying around) so signal may get unreliable. Reliability of GPS signal for basic en-route navigation is phenomenal, it is WAAS that sometimes may be unavailable (worst in Alaska but in my CA precision approach availability at 99.75% - and this is considered one of the worst for the continental US). I can live with these odds.
 
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labbadabba said:
They've had a quite a few GPS outages in that spot over the past 12 months. I know they're doing some drills on non-GPS guidance systems for the military. I know they're bringing back celestial navigation for the Navy guys. Wonder if they'll do the same for tankers and bombers...
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I suppose for long distance, over water NAV they could bring back the sextant but for most ops, it wouldn’t be necessary.

The military doesn’t put all its eggs in the GPS basket. In a high intensity combat scenario, their encrypted GPS would have to be jammed / spoofed. If somehow that happens, they have INS. If somehow that fails, you go to pilotage DR on an iPad with paper backup. But If things have gotten that bad, I’d have far more pressing concerns in combat than losing NAV. ;)
 
aterpster said:
True enough. But, the loss of GPS will constitute an emergency. If VFR remain VFR if able and land at a closer suitable airport. With ADS-B ATC should be able to assist just about everywhere.
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How is ADS-B going to do anything if GPS is out, ATC is back to good old-fashioned Primary/Secondary radar at that point.
 
nauga said:
Maybe it thought you were going to stop?

Nauga,
ceasing buzzer
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lol! Brings back some memories. Never had to use “buzzer” before on approach but I’ve seen some of the interference EAs can cause. Told some Hornets to “Stop streamer / burst” once. Used to always have to tell Tomcats to turn off their AWG-9 during PARs also.
 
aterpster said:
True enough. But, the loss of GPS will constitute an emergency. If VFR remain VFR if able and land at a closer suitable airport. With ADS-B ATC should be able to assist just about everywhere.
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A true child of the magenta line! Losing GPS is an emergency . . . . :cryin: That's why you should have two nav/coms in your plane.

I had no trouble flying home after a total electrical failure. And I had no trouble navigating around some buildups on my first trip to an airport on the edge of ATL Bravo space after updating my GPS card and leaving it at home . . .

If you can't fly without the pink line, please, please spend some time with a CFI until you can!!
 
Hank S said:
A true child of the magenta line! Losing GPS is an emergency . . . . :cryin: That's why you should have two nav/coms in your plane.

I had no trouble flying home after a total electrical failure. And I had no trouble navigating around some buildups on my first trip to an airport on the edge of ATL Bravo space after updating my GPS card and leaving it at home . . .

If you can't fly without the pink line, please, please spend some time with a CFI until you can!!
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Since most or all of his airline career was before GPS was available in airliners, I think the chances of aterpster being a "child of the magenta line" are pretty much zero. Looking at the post he was replying to, I believe his comment was in the context of an IFR flight that is not within fuel range of a land based navaid.

I started this thread in the "Cleared for the Approach" section in recognition of the likelihood that the consequences of loss of navigation signals may be more serious for IFR flights than VFR ones.
 
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Palmpilot said:
Since most or all of his airline career was before GPS was available in airliners, I think the chances of aterpster being a "child of the magenta line" are pretty much zero. Looking at the post he was replying to, I believe his comment was in the context of an IFR flight that is not within fuel range of a land based navaid.

I started this thread in the "Cleared for the Approach" section in recognition of the likelihood that the consequences of loss of navigation signals may be more serious for IFR flights than VFR ones.
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Thanks. I got my instrument rating in 1958. Went with the airline in 1964, retired in 1990. Still active in the technical aspects.
 
Hence the implimentation of E-Loran is necessary. Its the new and improved version of old C-loran. GPS signals are very easily jammed.
 
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Cruiser12 said:
Hence the implimentation of E-Loran is necessary. Its the new and improved version of old C-loran. GPS signals are very easily jammed.
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It's never going to happen. The airlines don't need it.
 
kontiki said:
Idiots can also buy cheap jammers. Its a very low power signal.

http://newyork.cbslocal.com/2013/08...ce-interferes-with-newark-liberty-operations/
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Yes, seriously, this was a problem in and around KVLL and KPTK when I was working on my instrument rating. Some fool, maybe a local trucker trying to defeat his company's location monitoring, was causing trouble so often that there were NOTAMs at KPTK about it. The first time it happened to me, I was shooting approaches with my first CFII at KDET, so the guy definitely got around. It caused a complete loss of satellite reception, and until I had corroboration from other pilots I was thinking it might be a malfunction on my end. I hope they caught him, but I have no idea if they ever did. I think the NOTAMs were gone last time I checked though, thankfully.
 
One should also remember that we're about one solar flare away from losing multiple GPS satellites.
 
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