Is a second GPS needed vs a second Nav radio?

WDD

Final Approach
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Vintage Snazzy (so my adult children say)
Having a second radio makes sense if for nothing else you can have it dialed up and ready to flip to when changing say from Arrival to Tower.

With the reduction of VOR towers to MON, with ILS approaches declining, LVP approaches becoming more numerous, does it make sense to need a second Nav radio? Does it make sense to have instead a GPS back up?

If you got a new 225 Com only vs a 255 Nav/Com, the money you save would just about pay for getting a 375 Transponder/GPS vs just a 345 GPS.

Thoughts?
 
I can't remember the last time I actually needed a _single_ nav radio in real IFR flying, let alone a second one. So I'd say that having one is appropriate as a backup to GPS, as in a GPS outage. But having two would be superfluous.

I CAN remember the last time I actually needed a second GPS receiver due to equipment problems. So I'd say having a second GPS receiver as a backup is prudent.
 
If the second gps is also a Com/NAV capable, you get the best of all worlds. Pricey, but it is what it is.
 
Having a second radio makes sense if for nothing else you can have it dialed up and ready to flip to when changing say from Arrival to Tower.

With the reduction of VOR towers to MON, with ILS approaches declining, LVP approaches becoming more numerous, does it make sense to need a second Nav radio? Does it make sense to have instead a GPS back up?

If you got a new 225 Com only vs a 255 Nav/Com, the money you save would just about pay for getting a 375 Transponder/GPS vs just a 345 GPS.

Thoughts?
If ya wanna be able to fly when all the satellites get shot down or run into space junk and self destruct then yeah, you should have some Nav radios. A DME/DME RNAV would be pretty cool to. But then, if the whole where'd the satellites go thing happens, I don't think there is going to much recreational IFR flying allowed. In other words, nah, you don't need a second one.
 
My thought for a second Nav unit is based on an experience I had with a rented Tiger a year ago. The GNS 430 light sensor went bad and the screen went dark thinking it was night time. I had to use the second com to communicate, and as I was VFR I didn't need to fly an approach. If I was IFR it would have been a problem. If I had a GPS unit combined with the transponder it would be an independent back up.
 
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I have one IFR certified GPS and somewhere around a half dozen VFR GPS receivers in the plane. I do have dual nav/com (one set in the GPS, and a standalone SL30). If the GTN650 dies, I can still muddle my way to the FAF of an ILS and get on the ground. At least, that’s my theory. With sufficient altitude and radar vectors in the terminal area , I shouldn’t have any severe problems using the VFR GPS receivers to not die. Perfect? Probably not. But a used SL30 used to be way cheaper than a new panel mount GPS :).
 
When I was planning my avionics, I considered a second NAV radio... for about 30 seconds. Ended up with 2 Com, 1 Nav, and a GPS. The only time I ever used the nav radio was for ILS approaches. Tuned in VOR's on cross country trips just to pass the time.
 
Well the panel was already in pieces. So, I decide to add a 650 to go with the 750. Is it needed? Well IDK:dunno: I use it to monitor traffic…
 
Well the panel was already in pieces. So, I decide to add a 650 to go with the 750. Is it needed? Well IDK:dunno: I use it to monitor traffic…

Gold plan panel there. Do you have to pay two update subscriptions to Garmin or do they let you get away with just one?
 
When I was planning my avionics, I considered a second NAV radio... for about 30 seconds. Ended up with 2 Com, 1 Nav, and a GPS. The only time I ever used the nav radio was for ILS approaches. Tuned in VOR's on cross country trips just to pass the time.
*sigh* if only the FAA would allow us to check the VOR against the GPS...

If ya wanna be able to fly when all the satellites get shot down or run into space junk and self destruct then yeah, you should have some Nav radios.
I'd be much more concerned about jamming, friendly or otherwise.
 
Gold plan panel there. Do you have to pay two update subscriptions to Garmin or do they let you get away with just one?

Well, Garmin sells bundles depending on what you have installed, but to answer your question your paying for a subscription for each unit.
 
I think it makes sense to have one GPS navigator and another NAV radio that uses ground based equipment. A 650 and 750 would double up on that idea, and may be overkill, but I think better than having all your eggs in the GPS basket. Most of us say something like "it won't happen to me" as far as being in the air in bad weather when something happens to the GPS system, but the FAA is concerned enough that it is maintaining the ground based equipment, just not all of it. My understanding is that GPS signals are fairly weak and are easily jammed, whether by a foreign or our own government or just some kind of terrorist cell. Do you want to bet your life and the lives of whomever is flying with you on nothing happening to the GPS system? Not me.
 
Last time I needed a VOR , unplanned, was about one year ago. Leaving El Paso, Westbound. GPS outage hits!!

I was already tracking V198 passing the restricted balloon airspace (R-5115). The VOR was already tuned-in to define the airway and verify the magenta line.

It was a non-event. The airlines above me were complaining and asking for vectors.
 
I've flown for 20 years IFR/VFR with one GNS480 and one SL30.
Never seen the need for additional nav.
 
A second GPS nav box seems superfluous for a light single. A #2 NAV/COM with ILS is a nicety if GPS signals crump, so you can shoot an ILS or VOR approach in a GPS outage. A #2 NAV is a nice backstop. It's more important, however, to have a backup COM than NAV. If IFR communication with ATC is your #1 safety net. I've flown IFR for quite a while with one GNS-430W and an old #2 NAV/COM with a non-mechanical CDI. Since the GNS-430W went in, I have never used the #2 for anything but monitoring ATIS and contacting ground. (Well, maybe during an IPC for kicks and grins, just to demonstrate I can still use it.) The GNS-430 has (partially) failed only once in 20 years. (lost vertical navigation, so no LPV, but still maintained LNAV integrity.) If the GNS-430W completely fails, I have a hard-wired Aera-510 that gets XM-WX for positional and WX awareness. Plus a GPS-enabled EFB. Those will be enough to get me on the ground if NAV#1 crumps.
 
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I have a 530W and a 430W (cross-linked), and I typically use the 430W as either a dedicated traffic scope for the ADS-B, or have it on terrain at night, second comm for atis, ground, etc. Plus its a backup GPS fully integrated into the G5 HSI, so could use for Enroute, LPV, or ILS if needed. Another nice thing is it can be used to have your missed queued up in GPS mode from an ILS which you're flying with Nav1, so you can just switch the HSI to GPS2 and fly the missed.

So 100% necessary, no, but nice to have for sure.
 
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