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Ok to skip NAV radio?

ConnyJ35

I'm New Here
A bit struggling to choose between Garmin 225A COM and 255A COM/NAV.

I will install a G3X and a GNX 375. Most likely I will only fly VFR with my 7 (even if I have Instrument rating), but it is nice to have an IMC approach backup just in case. LPV approaches are possible with the GNX /G3X which would do the trick.

So, any disadvantages with skipping the VOR/ILS radio (and that ugly antenna) and go with just the 225? But I might have missed something?

If I go with the “COM only”, I would have preferred the GTR 200B over the 225 as the 200B intercom apparently is superior of the one the 225, but as I need a radio wit 8,33 spacing it seems the only way to go is the 225.
 
You’ll get some pretty passionate responses to this question but I’m not installing anything but a single comm and the GNX 375. There are many of us who believe the VOR/ILS is no longer needed. AND it really simplifies wiring.
 
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I went with a Dynon HDX and Garmin 175. Did not want the complexity and Antennas involved in a VHF nav installation.
 
Answer: It depends.

Some DPEs require you to perform a non-GPS approach. If you are already IFR rated, it is only needed as a backup if/when GPS signals are not available (e.g. military jamming).

I am not yet IFR rated, so I plan to install a Nav/Com/GPS navigator for training and to ensure I can do my check-ride in my plane.
 
IFR equipment

I thought I just read something the other day that in Europe there is a requirement for a secondary navigation source if flying IFR? If so, a single box with just GPS would be inadequate per the regulations. Further the 2nd source had to be a different 'box'. Something to check.
 
Antennas

Oh, BTW, my VOR antenna is in a wingtip, and my GS antenna is just forward of the rollbar on my slider. No external antennas. You could go simpler yet an only support VOR/LOC (no ILS/GS). That's typically a cheaper radio and you do have a secondary NAV to satisfy comfort and regs.

I see LOTS of GPS unavailable "due to testing" NOTAMS around the military areas out here.
 
Aircraft mission??

If you (or a someone else) plans on getting their IFR ticket in this plane, install a GTN-650. If not but you want IFR capability, install the Garmin 175.

90 percent of my flying is cross country IFR (GTN-650 and dual screen Dynon SkyView). While all but one of my “real” IFR approaches have been RNAV, I needed the VOR/LOC/ILS function to get my IFR ticket in what was then my new RV-10.

For the next (and final RV) I will still have the dual screen SkyView, but may go with the Garmin 175. If so I’ll install two Dynon radios (I was not impressed with my experience flying behind the Garmin GTR-200B radio - and I assume the 225A is just a modified version of the 200). The decision between the GTN-650 and one Dynon radio or the Garmin 175 and two Dynon radios will be based on what deal I can get.

Carl
 
I installed a MGL N-16 with a Vega controller. It uses SL-30 protocol and works fine with the G3x. It can also functions completely independent of the G3X, which is one reason I went this route. If you decide to skip the vor/ils nav, this is something you could easily add later if you decide you wanted it. The controller needs a standard 2.25” instrument hole.
 
my 2c, here goes:

When I bought my ship, I replaced the obsolete non-8.33 COM with the 225A...
Later I added dual G5 and a GNX 375. And would buy a 255A if it were today...

The 375 guides you with amazing precision on those FPV (and non-) approaches, no question about it. But. Having the 255A will give you one more level of redundancy, never know when or if you will need it... but it is "only" a couple of hundred $ more, and the antenna can be hidden under the cowling ;)
 
My non-RV has a VOR receiver. I rarely use it. But a few times, flying day VFR, it has really come in handy.

Still, I'm not putting one in my RV-3B project. Why? It's such as small plane I don't want to give room to it.

Dave
 
What are you going to do with a widespread GPS outage? It happens more often than you think...
 
Yep, depends on what you’re comfortable with. I’ve experienced one unpublicised gps outage at the end of an approach (vmc by then), never did find out the cause. But it does happen, as does having a box let out its magic smoke.
 
Thanks everyone for inputs!:)
I think after having read all the comments, I will for now skip the 255 NAV and go with COM only.

I will not fly IFR with the 7, I am not even sure my RV can be IFR approved, rules are different between the countries here in Europe. Some countries demand certified instruments etc.

My IFR flying/ check rides will be done in other aircrafts. Until retirement…
The RV will be flown in nice weather. But I want some kind of equipment making an IMC approach makeable without disaster if something gets wrong.

Maybe when I have retired, I will try to get the RV approved for legal IFR. So it might be a good idea to install a wingtip antenna and wire to simplify a VOR/ILS installation. But by then maybe GPS reliability has improved.

Oh, by the way,got a Garmin watch for Christmas, with a VOR receiver:eek:! Problem solved!:cool:
 
I have a GPS 175 and an SL30. I only use the Nav function when departing a busy area and departure tells to intercept a certain radial and then on course. Haven’t flown but one ILS, a practice approach, since I got my RV9. All approaches have been RNAV GPS and that hasn’t created any issues whatsoever. BTW, my VOR antenna is in the wing tip.
 
I have a GPS 175 and an SL30. I only use the Nav function when departing a busy area and departure tells to intercept a certain radial and then on course. Haven’t flown but one ILS, a practice approach, since I got my RV9. All approaches have been RNAV GPS and that hasn’t created any issues whatsoever. BTW, my VOR antenna is in the wing tip.

Thanks! To me it sounds as most pilots don´t use the VOR/ILS a lot except for redundancy when/if GPS is u/s and check rides. So I heavily leaning on a COM solution. Will probably suit me best. Just got the price of the ELT...can sure need the money saved... Expensive stuff....
 
Ever used for real?

I'm always amazed at how often I hear or see comments of the need of VOR/ILS capability and how GPS is or may go offline when needed. I referring to GPS satellite interference causing an offline condition here and not a failure of internal aircraft equipment.

I never read or hear of a real life instrument approach in IMC when there was no GPS to be used or a nearby alternate RNAV airport was unavailable.

Sure GPS signal may be lost when tracking a flight plan route, but always comes back up and ATC is there to help if needed.

If someone has made the investment in NAV equipment and is keeping current with it they need to stay committed.

However, a handheld NAV/COM can get you down in an emergency. I've never needed it for real, but, I've used mine to track MON-VOR sites and shoot ILS approaches a number of times. It's takes a little practice to maintain the Glideslope with a handheld, but it's much easier than the old days of depending on ADFs as backups.
 
There are 3 things I like about adding the ILS capability, none of which are necessarily that compelling, but I did begrudgingly go from the gnc355 to a gtn650xi.

For the OP it is pretty much not a big deal, as stated it won’t be an IFR bird.

1/ If your plane has a gps failure, you still have a glide slope and nav. In this case I mean the plane itself. Not super duper common by any stretch. But I’ve been in a plane that had its antenna fail. Again, corner case to be sure

2/ I like having the ability to dial in the ILS without needing to put in a full approach. Especially at night or in an unfamiliar area. I realize this may be not needed with synthetic displays, but it is like a blankee—hahaa

3/ if your subscriptions aren’t up to date you can always fly a ground based approach with just the plate. This could be an accidental lapse, server gone bad, corrupted DB, or if you get cheap in the future.

Just something to toss in there.
 
I never read or hear of a real life instrument approach in IMC when there was no GPS to be used or ...

Okay, here’s one: a few years back I was right seat to an instrument student in an RV10, doing the required cross country. It was actual IMC, with low ceilings but temps above freezing, perfect for training! We planned on the LPV approach at Chico (CA). But when we got there, the ceiling had dropped to a reported 200’, and the LPV minimums were 300’. We switched to the ILS, broke out at 230’. So, never say never. As I already mentioned, on another flight, near the end of a gps approach, we got the dreaded red x across the screen, no gps nav. We were by then in vmc, but if we had still been imc and had no other nav backups, it would have been ‘interesting’: LVK is in a valley, 4000’ ‘hills’ not too far away. And below radar service. We would have had to fly the miss by headings alone until we were high enough to regain radar coverage.
 
What are you going to do with a widespread GPS outage? It happens more often than you think...

I have only had a GPS outage flying in the Middle East where the signals were jammed. Even that was localized. If I were to encounter a signal failure I would inform ATC if IFR and request vectors. If VFR I would have to use a chart.
 
New IFR Panel

I debated whether to include ILS/LOC capabilities in my RV 4, but, after talking with Valerie Steen at SemiPlane LLC at 50F, I ultimately decided to install the GNX375 with the G3X and add Nav capability with the Val Nav 2000 (Bob Archer antenna installed in the wingtip) which nicely integrates with the G3X.

Thanks to SemiPlane and the phenomenal installation they did on my plane, I now have a robust IFR platform!
 

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No VOR needed

quote from Carl "If you (or a someone else) plans on getting their IFR ticket in this plane, install a GTN-650. If not but you want IFR capability, install the Garmin 175."

Please don't be so dogmatic on this Carl. As I have mentioned on many threads on this subject, I did all my IFR training and did my checkride in my RV without a Nav radio in the plane.

You just need to find a DPE that will consider an LPV approach down to 200 feet the same as a ILS precision approach.

If the OP were to follow your advice of buying 650 instead of the 175, It would cost him an extra $6800
 
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I'm always amazed at how often I hear or see comments of the need of VOR/ILS capability and how GPS is or may go offline when needed. I referring to GPS satellite interference causing an offline condition here and not a failure of internal aircraft equipment.

I never read or hear of a real life instrument approach in IMC when there was no GPS to be used or a nearby alternate RNAV airport was unavailable.

I don't know about the nearby RNAV options, since we did not need to utilize them, but for what it's worth I've experienced a lack of RNAV availability maybe 4 or 5 times in actual IMC. Half of those were in light GA aircraft like an SR22 or DA40, the rest in a Gulfstream IV.

If I was the OP, I'd put in a non-glass, low-cost VOR/LOC solution, maybe even something used, skip the glideslope capability, and call it good. Regardless of the legality, I'd be a wee bit uncomfortable flying in real IMC with only one navigation system, whatever it may be.

--Ron
 
You just need to find a DPE that will consider an LPV approach down to 200 feet the same as a ILS precision approach.

No, that’s not the issue. The preface to the ACS (nee PTS) says that’s okay. The issue is the required ‘two different types of non-precision’ approaches. Some examiners take that to mean two different types of navigation aids, which means gps is just one. Others will count lnav and lpv to a DA above 300’ as 2 different types, while lpv to below 300’ is a third, precision approach. What’s really needed is some clarification from the faa.
 
Skip

I intend to just go with gps to a g3x and a back up G5. I will however have a handheld nav/com available in the cockpit(back up com ability and a pretty good ILS). With the FAA shutting down VOR sights, it seems they are sinking a bunch of funding into making the GPS system far more reliable than current and moving further away from navigational radios. Just my opinion.
 
Flying professionally and privately since >40 years :)eek:), mainly living in the EU, used GPS since it’s debut, who remembers the first no-database Garmin 100? OMG :D

GPS outage, when, where?
Twice in the whole period. Same place. Flying low (VFR) in between the mountains over Corsica France, probably military induced, thanks :(

Lookin forward to the virus cloud lifting up, got some missions scheduled far North :cool:
 
I've got a dumb question now.

A Garmin GPS175 - does it have the standard procedure database that something like a GTN650 or GTN750 has?

If I wanted to use the GPS175 for DME purposes on an ILS, would it still show all the same fixes that a full NAV unit would?

I bet the answer is yes, but I'm wondering now....
 
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I've got a dumb question now.

A Garmin GPS175 - does it have the standard procedure database that something like a GTN650 or GTN750 has?

If I wanted to use the GPS175 for DME purposes on an ILS, would it still show all the same fixes that a full NAV unit would?

I bet the answer is yes, but I'm wondering now....

It does indeed. You can also DL the simulator if you have an iPad to see what the display looks like.
 
As mentioned it will do all of that. It’s basically the entire GPS navigation system stripped out of the 650 and functions virtually identically. It has some flight plan upload and download features I don’t think the 650 had.
G
 
I never read or hear of a real life instrument approach in IMC when there was no GPS to be used or a nearby alternate RNAV airport was unavailable.
Here is another completely unannounced GPS failure, but in actual IMC with low ceilings. All aircraft arriving to local area airports reported the GPS failures during that time. IDK but maybe accidental jamming by the Navy off the NE Florida shore.

https://vansairforce.net/community/showthread.php?t=182900

It isn't a matter of IF it happens, it's a matter of WHEN it happens.

:cool:
 
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