A new panel with only GPS navigation for IFR flying

MountainDude

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MountainDude
I have been a VFR pilot only, so not very good at all the IFR gadgets.
Have an old Cessna 182 with the original panel from the 70s.
If I can get an instrument rating with GPS only navigation and approaches, what would be a good value panel?
I would want to remove the vacuum system, old NavComs, and the VOR/ILS indicators. I already have a great engine monitor.
What do you think of: 2 G5s, a GPS 175s, and AeroCruze 100.
Would Dynon have a competitive option but without any VOR/LOC/ILS capabilities?
 
For IFR flight, an IFR GPS only is adequate. For IFR training (at least a few hours) and the check ride, you will need to fly a VOR and ILS approach. There is some talk of removing the radio nav requirement, but it isn’t gone yet. For budget, you could just install the GPS and borrow/rent a plane for the few hours of training and check ride.

The Dynon would work great, but runs about $8-10,000 more than 2 G5’s. It is well worth the upgrade in functionality in my opinion, though.
 
I would want to remove the vacuum system, old NavComs, and the VOR/ILS indicators.
Why would you want to remove the old NAV/COMs? You'll still need COM radios, so why not leave them in? What would you replace them with?
 
The new Instrument ICS, that goes fully into effect in May allows GPS only for check ride.

A letter from the FAA allows GPS only now, but it is not required, so up to DPE.

 
For IFR flight, an IFR GPS only is adequate. For IFR training (at least a few hours) and the check ride, you will need to fly a VOR and ILS approach. There is some talk of removing the radio nav requirement, but it isn’t gone yet. For budget, you could just install the GPS and borrow/rent a plane for the few hours of training and check ride.

The Dynon would work great, but runs about $8-10,000 more than 2 G5’s. It is well worth the upgrade in functionality in my opinion, though.
I want to get IR and fly IFR without using VOR/LOC/ILS, so I will remove them from my panel.
 
Personally, I like having options especially when IFR in IMC. There's been a number of times I've flown an IFR flight into an area with NOTAM'd GPS outages. I'd have never launched if I hadn't had VOR/LOC/GS capability in the panel. There was another time when due to traffic flow and airspace, an ILS was the only "available" approach--the issue could have been forced but I don't want to be that guy short of an emergency. YMMV....
 
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Having 2 radios seems like a good idea, especially if someone wants to fly IFR. Just add GNC215 for the win. Given foreign abilities to spoof and degrade GPS, having at least one VOR is a nice idea. Should the GPS fail for whatever reason, VOR back-up is reassuring.

Any flying, especially IFR, with only one radio would fall below many pilot's personal minimums. You will want to get ATIS/ASOS while continuing to monitor ATC.
 
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If I can get an instrument rating with GPS only navigation and approaches, what would be a good value panel?
You can. The new Instrument ACS allows it. It's effective date is at the end of May. (It can be used now, but that's not going to be an issue if you are first starting.

FWIW, I think you are making a mistake planning to get rid of your VLOC equipment. There is such a thing as GPS failure. Of course, if you are fine grounding yourself for no good reason , by all means, go for it.
Would Dynon have a competitive option but without any VOR/LOC/ILS capabilities?
No as far as I know, and I'd bet the price differential would be small if there were one.
 
I want to get IR and fly IFR without using VOR/LOC/ILS, so I will remove them from my panel.
What make/model are the existing radios? Would be helpful to know if they are NAV/COM versus separate NAV+COM.
 
Personally, I like having options especially when IFR in IMC. There's been a number of times I've flown an IFR flight into an area with NOTAM'd GPS outages. I'd have never launched if I hadn't had VOR/LOC/GS capability in the panel. There was another time when due to traffic flow and airspace, an ILS was the only "available" approach--the issue could have been forced but I don't want to be that guy short of an emergency. YMMV....
I understand that works for you, but will not work for me. It's good to have options.
 
Having 2 radios seems like a good idea, especially if someone wants to fly IFR. Just add GNC215 for the win. Given foreign abilities to spoof and degrade GPS, having at least one VOR is a nice idea. Should the GPS fail for whatever reason, VOR back-up is reassuring.

Any flying, especially IFR, with only one radio would fall below many pilot's personal minimums. You will want to get ATIS/ASOS while continuing to monitor ATC.
Yes, I will have 2 radios for sure.
 
What make/model are the existing radios? Would be helpful to know if they are NAV/COM versus separate NAV+COM.
They are both the original NavComs. If I get rid of VOR indicators, I could still keep my radios, but if I am going to get a new panel, I will likely get new radios.
 
You can. The new Instrument ACS allows it. It's effective date is at the end of May. (It can be used now, but that's not going to be an issue if you are first starting.
That is really one of the best developments in GA since Basic Med. Thank you for confirming.
 
Not sure I understand your desire to ditch both NAV/COMs unless they are compete crap but you know what you want and there’s nothing wrong as with that. Regardless you’ve got to retain a CDI for the GPS unless you do upgrade to an EFIS or HSI which if you do will display both GPS and VOR/LOC/GS indications if you so desire.
 
Not sure I understand your desire to ditch both NAV/COMs but you know what you want and there’s nothing wrong as with that. Regardless you’ve got to retain a CDI for the GPS unless you do upgrade to an EFIS or HSI which if you do will display both GPS and VOR/LOC/GS indications if you so desire.
Sorry I did not explain the motivation behind this thread (it was not the point).
In my estimate, I will fly 1-4 hrs in light IMC (think a few clouds or a thin cloud layer around an airport) per year (yes, year). Given my busy life, I would not be a safe pilot if I tried to maintain proficiency with VOR, LOC, ILS, and GPS navigation/approaches. That is why I have not gotten IR.
However, if I can obtain and maintain IR with just GPS, then I can maintain my proficiency and fly safely.
Since none of my trips are mandatory (I can cancel/change any time), I will cancel if there is a GPS outage, so not concerned about that at all.
 
Ok, but just so you know it’s the same amount of work maintaining currency and proficiency regardless of the type of approaches you fly and you still have to learn it all for the written and oral regardless of what you fly on your checkride or expect to fly in real life.
 
so in the 4 years i've had my IR, i've NEVER used the nav equip. yes, i'll do the 30 day checks but i never really use them for navigation.
that being said i did have a radio failure just a few weeks ago. long story short, the crsr button came apart in flight preventing me from changing the comm channel or selecting an IFR approach, while i was actually ifr, like in a cloud ifr, really sucked. Funny thing, i still didn't use the nav equip, i followed the existing pink line and asked atc for lower to get under the clouds.
 
Ok, but just so you know it’s the same amount of work maintaining currency and proficiency regardless of the type of approaches you fly and you still have to learn it all for the written and oral regardless of what you fly on your checkride or expect to fly in real life.
My understanding is that:
1. I have to learn it all once for the written, which is not a problem at all.
2. I will not have to learn or maintain proficiency in VOR/LOC/ILS navigation and approaches. How is that the same amount of work as using the GPS navigator only? Just by removing the need to calibrate the stupid VOR receiver every 30 days is less work. Not having to remember how to run the VOR is also less work, since a) I would not use it very often even if I had it, and b) I dislike the whole concept to the same degree I dislike flip phones.
 
Flying IFR enroute and approaches regardless of the nav source is basically the same skill set. GPS can simplify the routing in some but not all airspace and GPS offers more approach options throughout the NAS. However, GPS can create more workload as the buttonology is more complex. Maybe you should start your training before you make any significant panel decisions.
 
Flying IFR enroute and approaches regardless of the nav source is basically the same skill set. GPS can simplify the routing in some but not all airspace and GPS offers more approach options throughout the NAS. However, GPS can create more workload as the buttonology is more complex. Maybe you should start your training before you make any significant panel decisions.
I agree with what you said, but I am not comparing GPS to others. I am comparing GPS-only to all nav/approach methods combined. And I am sure maintaining proficiency is easier when focused on only one method.
I also agree with your suggestion to start training first, then make the final panel decision. However, that may not be possible. For example, it would make no sense to keep all my navcoms/needles, add G5s and G175, then decide later to remove the old stuff and add 2 new radios. I think that would cost a lot more.

My plan is to find a local CFII who will agree with my plan, help me plan the GPS only panel, find a DPE that will agree to do a checkride with GPS only, and then train me. Will see how that goes.
 
Given my busy life, I would not be a safe pilot if I tried to maintain proficiency with VOR, LOC, ILS, and GPS navigation/approaches.
VOR, ILS, LOC, and LNAV/LPV approaches are functionally identical to fly. Not sure why flying all these different approaches would be a training/currency burden.

In the real IFR system, I've been assigned and flown as many ILS approaches as I have LPV approaches. Having redundancy in NAV sources is a good idea if you already have it. You don't know when there might be a GPS outage or have a GPS unit fail. (I've experienced the latter.) An existing VOR/LOC/ILS will be a lot cheaper for redundancy than a second IFR GPS unit.
 
VOR, ILS, LOC, and LNAV/LPV approaches are functionally identical to fly. Not sure why flying all these different approaches would be a training/currency burden.

In the real IFR system, I've been assigned and flown as many ILS approaches as I have LPV approaches. Having redundancy in NAV sources is a good idea if you already have it. You don't know when there might be a GPS outage or have a GPS unit fail. (I've experienced the latter.) An existing VOR/LOC/ILS will be a lot cheaper for redundancy than a second IFR GPS unit.
Thank you for your input.
I agree they are functionally similar, but remembering to work dual VORs is not easy if you are not proficient. I think (but not sure) that some LOC approaches are more complicated than a typical RNAV approach due to step-downs, where you have to calculate the descent rate based on your speed. Very primitive compared to GPS.

While others have been assigned non GPS approaches, I will only fly to airports where GPS approaches are available, and I will add to my flight plan that I only have GPS - that way the ATC will not assign me to something else.

Given that I plan to fly 1-4 hrs of light IFR per year, I am not worried about either a GPS outage or a GPS failure (though I may install a redundant navigator - have not decided that yet).
 
I think (but not sure) that some LOC approaches are more complicated than a typical RNAV approach due to step-downs, where you have to calculate the descent rate based on your speed.
LNAV approaches also have step downs. You will discover that using the advisory vertical guidance for LNAV approaches, when available, can get you into trouble if you are not aware of how it works. I prefer to fly step-downs because it gives you a better chance to break out into VFR earlier during the approach. You will discover this and other relevant things about IFR flying during your training.
 
have to agree with the guy above "VOR, ILS, LOC, and LNAV/LPV approaches are functionally identical to fly", having only a gps isn't going to save you anytime, it'll just leave you with less options in the not so common case gps fails. Even though i don't really use my nav radios, I'll maintain one, well until they come out with e-loran
 
have to agree with the guy above "VOR, ILS, LOC, and LNAV/LPV approaches are functionally identical to fly", having only a gps isn't going to save you anytime, it'll just leave you with less options in the not so common case gps fails. Even though i don't really use my nav radios, I'll maintain one, well until they come out with e-loran
Here is an experienced IFR pilot flying in his local area making a simple mistake on the VOR approach.
See around 7:20 mark.
I am not sure what "functionally identical means", but what I know is that:
- VORs have to be calibrated every so often (I think every 30 days)
- You have to maintain muscle memory to work them in different situations
- You have to tune in, listen to the Morse code (wow, we are going way back here), then adjust the OBS...
All this sounds simple if you use it all the time. But if you don't use it all the time (like I would not), then relying on it when you need it becomes dangerous, IMO.
 
there is no "calibration" it's a 5 second check to verify the things are still within spec.
the check ISN't required for an ILS approach
if you can fly a vor you can fly a gps, the equip in the plane works pretty much the same only diff being it's trivially more difficult to know your current position.

enroute flying is 99% identical gps/nav, you follow a green or pink line

truth is, if after getting the rating, if you can't maintain a minimum proficiency with a nav approach, you can't maintain proficiency with gps. full stop.
 
In the real IFR system, I've been assigned and flown as many ILS approaches as I have LPV approaches
OTOH, I’ve never been refused the RNAV when I’ve requested it instead of the ILS.

truth is, if after getting the rating, if you can't maintain a minimum proficiency with a nav approach, you can't maintain proficiency with gps. full stop

I don’t agree with the choice to forego VLOC, but truth is,

(a) there is no pressing need to fly VOR or LOC approaches, many of which we can’t fly anyway with our modern equipment if there is a GPS failure.

(b) I always include an ILS when I give an IPC because I’ve seen more errors by pilots than with RNAV. Not the act of intercepting and flying the lateral and horizontal paths. That’s the same. But the setup tends to be more complicated with the new boxes than it was before, with lots of opportunities for errors you don’t see with RNAV. So much so, that if they have an autopilot, I insist the approach be flown coupled.
 
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truth is, if after getting the rating, if you can't maintain a minimum proficiency with a nav approach, you can't maintain proficiency with gps. full stop.
I’d take it a step further, and say that the OP’s initial comments make it sound to me like maintaining ANY IFR proficiency isn’t going to be possible.
 
Here is an experienced IFR pilot flying in his local area making a simple mistake on the VOR approach.
See around 7:20 mark.
I am not sure what "functionally identical means", but what I know is that:
- VORs have to be calibrated every so often (I think every 30 days)
- You have to maintain muscle memory to work them in different situations
- You have to tune in, listen to the Morse code (wow, we are going way back here), then adjust the OBS...
All this sounds simple if you use it all the time. But if you don't use it all the time (like I would not), then relying on it when you need it becomes dangerous, IMO.

VOR receivers do not have to be "calibrated" every 30 days. They need to be checked for accuracy and logged. If you have a GPS/NAV/COM and a secondary NAV/COM, this can be done with a simple cross check between to the two to verify they are within 4 degrees of each other. Easy-peasy, takes one minute during a VFR flight. Having two navs makes this check very simple. It's a little more complicated if you have only one VOR receiver. LOC/ILS receivers do not have to be (and cannot be) checked in the same way. The LOC/GS receivers operate differently than a VOR.

The OBS serves no purpose on an ILS/LOC approach, although pilots may want to adjust it to the LOC course as a reminder of the approximate reference heading

I'm not sure what "muscle memory" is required for operating a VOR, but they are stone-simple. You tune a frequency, verify it is correct, and adjust the OBS to the desired radial. (OBS setting is not required for a LOC.) The CDI provides the same kind of left-right course deviation information as a GPS does for a GPS course. So flying a VOR/LOC/GPS approach is pretty much the same as far as the provided CDI information is concerned and what you do with it.

FYI, you have to do similar, but often more complex operations to set a GPS approach compared to a VOR/LOC/ILS approach. You typically must select an airport, an approach, and a transition, then load and/or activate it. Once activated, you may have to delete a HILPT or other course reversal if on a NoPT approach course to the IAF.

Many of these issues will become clearer to you once you begin IFR training. If you think using a VOR/LOC is complex, your IFR GPS training will disabuse you of that. The most challenging part of currency for me is refreshing all the GPS buttonology, especially when things get changed up by ATC on the fly. I don't think you will find that flying a LOC/ILS procedures is significant extra training overhead. I hand-fly ILS, LPV, and LNAV or LOC approaches on every IPC, and they all use pretty much the same IFR skill set. The ILS or LOC approaches are actually much easier to set up. Flying a course by CDI is a basic IFR skill.
 
OTOH, I’ve never been refused the RNAV when I’ve requested it instead of the ILS.



I don’t agree with the choice to forego VLOC, but truth is,

(a) there is no pressing need to fly VOR or LOC approaches, many of which we can’t fly anyway with our modern equipment if there is a GPS failure.

(b) I always include an ILS when I give an IPC because I’ve seen more errors by pilots than with RNAV. Not the act of intercepting and flying the lateral and horizontal paths. That’s the same. But the setup tends to be more complicated with the new boxes than it was before, with lots of opportunities for errors you don’t see with RNAV. So much so, that if they have an autopilot, I insist the approach be flown coupled.
No question, you can get an RNAV approach instead of an ILS if you wish.

Ironically, it is often easier to set up an ILS approach the old-fashioned way on NAV #2 than in the GPS box, but it's good to know how to do both, especially if there are DME/GPS requirements in the approach, and for more potential simplicity in the missed approach.

I haven't used VOR navigation in more than a decade. But it's there if the GPS system crumps for whatever reason.
 
VOR, ILS, LOC, and LNAV/LPV approaches are functionally identical to fly. Not sure why flying all these different approaches would be a training/currency burden.

In the real IFR system, I've been assigned and flown as many ILS approaches as I have LPV approaches. Having redundancy in NAV sources is a good idea if you already have it. You don't know when there might be a GPS outage or have a GPS unit fail. (I've experienced the latter.) An existing VOR/LOC/ILS will be a lot cheaper for redundancy than a second IFR GPS unit.
This ^^^^

Only difference is the color of the line on the navigator.

I am old school, and I would not have an IFR airplane without a VOC/LOC/ILS. VFR plane? No problem.
 
I will cancel if there is a GPS outage, so not concerned about that at all.
GPS outages often come as a surprise when already airborne.

GPS uses a very low power signal, as they're coming from satellites, which makes them easy to jam and susceptible to interference. The military jams GPS with some regularity. Accuracy can be degraded, to less than the RNP 0.3 needed for GPS approaches, from bad satellite geometry which is why there is the RAIM check.

To fly IFR without any other navigation sources, you'll need to consider your backup plan to unexpected loss of GPS when you plan your flights. If you are flying in areas without radar coverage to (near) the ground, this can be problematic. You'll need to think about how this will affect your planned flying and whether that's worth the savings, in money and proficiency, in the type of flying that you want to do.

Similarly, pay attention to how removing the vacuum system will affect your need for redundant power and standby instruments.
 
GPS outages often come as a surprise when already airborne.

GPS uses a very low power signal, as they're coming from satellites, which makes them easy to jam and susceptible to interference. The military jams GPS with some regularity. Accuracy can be degraded, to less than the RNP 0.3 needed for GPS approaches, from bad satellite geometry which is why there is the RAIM check.

To fly IFR without any other navigation sources, you'll need to consider your backup plan to unexpected loss of GPS when you plan your flights. If you are flying in areas without radar coverage to (near) the ground, this can be problematic. You'll need to think about how this will affect your planned flying and whether that's worth the savings, in money and proficiency, in the type of flying that you want to do.

Similarly, pay attention to how removing the vacuum system will affect your need for redundant power and standby instruments.
My understanding is that GPS outages are rare, and they are NOTAMed. If I am going to fly 1-4 hrs in IMC per year (yes, per year), what are the odds I will run into an unannounced GPS outage?

Yes, if I limit myself to GPS only, I will plan accordingly.
 
If I am going to fly 1-4 hrs in IMC per year (yes, per year),
You've stated this several times so I guess you're pretty sure of it. If that's the case, why get an IFR rating at all? Seems like a lot of time and expense for someone who knows he's almost never going to use it. Would probably be easier to just plan around that one trip a year.

I typically do recommend pilots get their IFR rating even if they don't plan on using it much, because I think that it makes you a better pilot and gives a lot more options, and (at least to some) is extremely interesting to learn. You don't seem interested in it, and don't plan to use it, so why bother?

Also, you seem to be treating VOR proficiency like you're in a unique situation. Believe me, you're not. Almost NO light GA pilot maintains any actual VOR proficiency. Most have probably gone years since tuning anything in on the VOR. BUT, it's there as a backup if needed, and when prompted to use it, most pilots eventually muddle through it somehow. It's not rocket science, and is a good tool to have in the back of your brain somewhere.
 
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My understanding is that GPS outages are rare, and they are NOTAMed. If I am going to fly 1-4 hrs in IMC per year (yes, per year), what are the odds I will run into an unannounced GPS outage?
What does "rare" mean? I encounter loss of GPS, usually a temporary condition, with some regularity. I fly around 700 hours per year. Most are jamming, intentional or not, and were not in our NOTAM package. My airplane degrades to DME/DME/IRU so the impact is minimal, only temporarily losing the ability to fly RNAV approaches and certain RNAV procedures.

Engine failures are rare, too. You still prepare and plan for them.

The question you need to consider is what you will do if you lose GPS during IMC. If you have a good backup plan, don't put yourself into situation where you don't have a backup, and can tolerate any delays it causes, then it's fine. I wouldn't just dismiss it as "rare".
 
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