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Grt and IFR

iaw4

Well Known Member
The IFR addon from GRT looks attractive, but I fear I cannot take a check ride in it. Has anyone talked to some examiners?

The grt page also says that they are not compatible with certain Garmin IFR equipment due to a proprietary Garmin protocol. Is this also the case for the gps175? What does this mean? Can it at least present a pseudo GS and CDI coming from the 175?

My needs are for soft IFR. I need to get the ticket, but will then be happy enough to set personal minimums above LNAV non-precision approaches Simply put, I am not arriving or departing into clouds lower than 1000? AGL.

Is an old 300xl compatible and sufficient for these needs? Is the GRT IFR legal for non-precision approaches? If I get a 175, do I lose all EFIS IFR support? Any other ideas for cost-efficient soft IFR in and out?
 
No such thing as ?soft? IFR

I?ve been using GRT products for IFR for years with Garmin navigators for years. Not sure what you mean about GRT not being compatible with each other.

On a side note, there is no such thing as ?soft? IFR. Prepare you and you aircraft for approaches to minimums because once you are in the sky things way beyond your control happen. Weather prediction is not a science. If you fly long enough you will get caught in weather that wasn?t forecast that you didn?t see coming.
 
The GRT stuff is not IFR legal unless you can convince your local FSDO it conforms to the TSO?s. Not worth the effort IMHO. A 175 will do what you need, work with the GRT EFIS of your choice, and is current technology. If you want to go inexpensive, look at a 400W (I did, very happy).

I applaud your concept of personal minimums, but remember you will never be more proficient than the day after you pass your IFR check ride (to a degree). So take advantage of that, if presented with some non-turbulent low overcast shortly thereafter. It will give you confidence and experience to adjust your personal minimums.
 
‘’The GRT stuff is not IFR legal unless you can convince your local FSDO it conforms to the TSO’s.’’’

Please explain the phrasing “Legal”. I guess I have been flying “illegally” for over a decade with GRT.
 
You?ll have to justify your statement

The GRT stuff is not IFR legal unless you can convince your local FSDO it conforms to the TSO?s. Not worth the effort IMHO.

Me thinks you are very incorrect with this statement. Please add some regulations to back up your statement.
We, and the folks at GRT will be interested in seeing that in writing.
 
The GRT stuff is not IFR legal unless you can convince your local FSDO it conforms to the TSO’s. Not worth the effort IMHO. A 175 will do what you need, work with the GRT EFIS of your choice, and is current technology. If you want to go inexpensive, look at a 400W (I did, very happy).
...

Yes and no.

The GRT, Dynon, Garmin, MGL, etc. are not "legal" for IFR on their own.

However, if they have a "certified" nav source to drive them, then they are legal to use IFR.

That "certified" nav source can be a simple VOR/ILS receiver or a something as complex as an Avidyne IFD or Garmin GTN/GNX/GNC/GPS.

(I'm not going to get into the legalities of using a modern EFIS without a "certified" nav source, which apparently happens fairly frequently.)
 
+1 on Bill?s post. Including the business of soft ifr. You need to pass the test to standards.
1. The grt efis units will fully interface with the nav functions of garmin?s 400/500/650/750/175 boxes, for ils/vor/gps approaches. As well as Avidyne?s 440 gps.
2. GRT is offering gps approach capability using its Hx/HXr efis boxes and an uncertified for approaches (not TSO?d) GPS. The database is within the efis. GRT explicitly states that at this time, this is for practice under vfr (or emergency) use only. Clearly they are hoping that with demonstrated use the faa will ease up on the rules, much like the way they now allow non-TSO?d efis units in normally certified aircraft. But currently these are not legal for actual ifr use.
3. I personally have sent an instrument student to a designated examiner in a RV-10, equipped with a GRT EFIS and a Garmin 430W. No issues.
4. Can you use #2 (GRT non certified gps) in vfr conditions? Yes. Will that be acceptable to the examiner? I don?t know. But really....
5. The check ride requirements currently require 3 different types of approaches. You cannot do that with just a gps, although some examiners are willing to work around this.
6. If you have ils/vor capability then you don?t need any gps at all for the practical test.
7. Yes, the grt will work with a garmin 300. But that non-waas box won?t do a precision approach, so you?ll need an ils for the test. See #6.
8. There are some Garmin software protocols that are proprietary, but they don?t affect navigation. For example, you cannot use a Garmin navigator to drive the GRT ADSB box, because grt cannot ?read? Garmin?s ADSB + protocol. Likewise, a garmin adsb-in box will display traffic on a garmin gps screen, but not on the grt efis screen. And many 3rd party adsb-in boxes that display traffic/wx on the grt screens will not display on the garmin screen.
 
1. I was indeed referring to http://grtavionics.com/home/efis-systems/horizon-hxr-efis/ifr-approach-option/ :

Can I legally fly an IFR GPS approach in non-emergency conditions in my experimental aircraft?

This is a legal question that we are not qualified to address. We make no claim regarding the legality of our GPS approach when intentionally flying in IFR conditions.

2. "There is no such thing as soft IFR...one day you will be caught." Well, in this case, there is also no such thing as VFR, either. One day you will be caught in IFR. Or feasible IFR...one day you will be caught with fog down to zero. yes, I want to prepare well for my IFR test in my airplane, but I do not plan to fly in the soup unless it is greatly above where I know I can fly.

3. My problem right now is equipping my airplane reasonably. I want to do pass the IFR checkride, so that afterwards, I can fly off when there is a thin cloud layer on the airport at 1000'. what makes sense for this scenario? I am guessing that VOR/ILS/GS will go the way of the Loran in a decade or two, because they are just too expensive to maintain in smaller airports; and putting the relevant into a modern airplane for my kind of use seems wasteful. BUT, is VOR stuff really what I need to do here?


4. what can I practically use for my checkride and for later non-precision GPS approaches?

5. The first route: When using a VAL Avionics NAV ($900) with the GRT, do I have everything I need legally? In this case, I could start with one, do my checkride, and eventually replace it with a COM. of course, it would mean I would want to purchase the IFR option on the GRT, too. I will hope that non-precision approaches are still "legal enough" with it. it should have more than enough accuracy for this...but no one has proven this.

6. How does the GS/ILS information look like with non-GPS sources? Is it all pretty much nicely overlaid over the map, so it is really almost like a GPS flight plan? I really don't want to go back to maps and radial computations in my head.

7. The other route: Can I use a GPS175 without linkage to the GRT by itself. I understand that some IFR examiners are beginning to be ok with this, inventing pretend-non-GPS approaches as-if-GPS for the checkride.

8. if I have a GPS 175, can it send information to the GRT to allow me to pretend (on my checkride) that I am flying a VOR/ILS/GS?


9. What reasonable low-cost equipment are other GRT IFR pilots using to be legal?
 
Whoa, did I touch a nerve amongst the sea lawyers with the word ‘legal’ ?

Plus 2 on Bill’s post.

What I meant in my OP was there was an assertion (referenced above) made by the GRT camp that one could potentially argue to a FSDO that an experimental aircraft equipped SOLELY with GRT equipment (specifically a GRT WAAS GPS) would satisfy the TSO 145/146 requirements, and be legal to operate IFR, to include LPV approaches. I do not think that particular argument is worth my time.

I, like many of you, have been happily operating IFR for years, using a GRT EFIS supplemented by a TSO 145/146 compliant GPS source, in my case a Garmin GPS400W.
 
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1. I was indeed referring to http://grtavionics.com/home/efis-systems/horizon-hxr-efis/ifr-approach-option/ :

Can I legally fly an IFR GPS approach in non-emergency conditions in my experimental aircraft?

This is a legal question that we are not qualified to address. We make no claim regarding the legality of our GPS approach when intentionally flying in IFR conditions.

2. "There is no such thing as soft IFR...one day you will be caught." Well, in this case, there is also no such thing as VFR, either. One day you will be caught in IFR. Or feasible IFR...one day you will be caught with fog down to zero. yes, I want to prepare well for my IFR test in my airplane, but I do not plan to fly in the soup unless it is greatly above where I know I can fly.

3. My problem right now is equipping my airplane reasonably. I want to do pass the IFR checkride, so that afterwards, I can fly off when there is a thin cloud layer on the airport at 1000'. what makes sense for this scenario? I am guessing that VOR/ILS/GS will go the way of the Loran in a decade or two, because they are just too expensive to maintain in smaller airports; and putting the relevant into a modern airplane for my kind of use seems wasteful. BUT, is VOR stuff really what I need to do here?


4. what can I practically use for my checkride and for later non-precision GPS approaches?

5. The first route: When using a VAL Avionics NAV ($900) with the GRT, do I have everything I need legally? In this case, I could start with one, do my checkride, and eventually replace it with a COM. of course, it would mean I would want to purchase the IFR option on the GRT, too. I will hope that non-precision approaches are still "legal enough" with it. it should have more than enough accuracy for this...but no one has proven this.

6. How does the GS/ILS information look like with non-GPS sources? Is it all pretty much nicely overlaid over the map, so it is really almost like a GPS flight plan? I really don't want to go back to maps and radial computations in my head.

7. The other route: Can I use a GPS175 without linkage to the GRT by itself. I understand that some IFR examiners are beginning to be ok with this, inventing pretend-non-GPS approaches as-if-GPS for the checkride.

8. if I have a GPS 175, can it send information to the GRT to allow me to pretend (on my checkride) that I am flying a VOR/ILS/GS?


9. What reasonable low-cost equipment are other GRT IFR pilots using to be legal?

Reference your #?s.
2. Ack! There is a world of difference between vfr and ifr. Most vfr into ifr accidents the pilot had plenty of opportunity to turn around, land, etc. You can do legal vfr with 1 mile vis (class G). That?s hugely different from 3. Under IFR, an approach into a 500? ceiling is (or should be) easy. 200? ceilings, a bit harder. But that?s just a 300? change. Forecasts often fail to be good to that accuracy.
5. Yes, a nav with ils, loc, and vor is sufficient for the test. As I already posted, the non-TSO?d GRT ?solution? is not legal at this time.
6. An inexpensive vfr gps will drive the grt moving map.
7. No. The G175 does not directly display GS information. But it does interface with the GRT displays just fine. You may need to hunt for an examiner that will count LPV approaches to 200? and LPV approaches to 400? as ?two different kinds of approaches?, for the test.
8. I have no idea if an examiner will let you fly gps data and pretend it?s something else. Hard to believe, but I?ve been wrong before.
9. The words ?low cost? and ?ifr? don?t go together. Are there pilots out there who fly ifr with a single source of attitude? Almost certainly. Am I one of them? Absolutely not. I have 3, and won?t depart ifr unless they?re all working. Flying ifr is all about risk mitigation. It?s never zero, and everyone has their own level of risk tolerance. That?s what makes internet discussions hard.
 
Don?t take this as a pile on but you need to get with an instructor or other knowledgable person and have them explain the basic requirements for SAFELY and LEGALLY operating in the system. Asking what is the cheapest option is really not the way you want to play ?you bet your life?.

An instrument ticket is some of the best training you can get and you are doing great by starting down this road. Good luck in eqquiping your ship.

And yes, there really is a difference between vfr and ifr.
 
for "what's required legal but not safe" I recall our old Piper Cherokee with vacuum steam gauges, paper maps, and two VORs. that was it.

for "what's safe but not IFR required legal," I will have three GPS's in my cockpit (separate antennas and power sources, some with 5Hz), plus one ADAHRS, plus an AHRS (neither with creeping failure, which I find most scary), plus battery backups, plus two moving maps not to lose perspective of where I am and where the mountains are (both with terrain awareness!), plus an autopilot that can hold the airplane steady to avoid disorientation and/or climb me out of soup, plus ADSB to see other traffic and weather, radios to talk if I am in trouble and need help, and a CO detector. none of this makes me IFR legal. but with appropriate training, it does make me fairly safe in IFR.

now, I also want to be legal.

---

we presumably agree that TSO'd is not necessarily much better than non-TSO'd, just more expensive. (if you do not, the GRT Horizon is out to begin with and we start at $50k and up.) we understand FAA certification is expensive and for legal IFR we need TSO in this case---but what does a $10,000 GTN-650 really bring to the table that makes flying a lot safer than flying with the non-TSO'd solution?

Jerry---I understand that you want to help me and others like me. maybe I am wrong. is the safety margin really much higher with a $10k GTN-650 over the triple-GPS non-TSO'd solution? or the $8k 400? or the $8k 430 with its VOR/ILS/GS? if it is, maybe I should reconsider.
 
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I think the way that GRT thinks of its system is that one should purchase a VALNAV 2000 for the legality for $1000 and add their $750 pseudo-legal IFR (legal for training and emergencies, but not primary intended). the solution is a $1,750 system that can really do it all, except for certain legal issues at some airports that have GPS but not other approaches.

I would love to try theGRT system in a simulator to see how their IFR solutions works with the VALNAC, but I do not think they have one. the videos are not great. :-(.
 
for "what's required legal but not safe" I recall our old Piper Cherokee with vacuum steam gauges, paper maps, and two VORs. that was it.

for "what's safe but not IFR required legal," I will have three GPS's in my cockpit (separate antennas and power sources, some with 5Hz), plus one ADAHRS, plus an AHRS (neither with creeping failure, which I find most scary), plus battery backups, plus two moving maps not to lose perspective of where I am and where the mountains are (both with terrain awareness!), plus an autopilot that can hold the airplane steady to avoid disorientation and/or climb me out of soup, plus ADSB to see other traffic and weather, radios to talk if I am in trouble and need help, and a CO detector. none of this makes me IFR legal. but with appropriate training, it does make me fairly safe in IFR.

now, I also want to be legal.

---

we presumably agree that TSO'd is not necessarily much better than non-TSO'd, just more expensive. (if you do not, the GRT Horizon is out to begin with and we start at $50k and up.) we understand FAA certification is expensive and for legal IFR we need TSO in this case---but what does a $10,000 GTN-650 really bring to the table that makes flying a lot safer than flying with the non-TSO'd solution?

Jerry---I understand that you want to help me and others like me. maybe I am wrong. is the safety margin really much higher with a $10k GTN-650 over the triple-GPS non-TSO'd solution? or the $8k 400? or the $8k 430 with its VOR/ILS/GS? if it is, maybe I should reconsider.

My concern here is safety and legality. You can shoot practice approaches all day long in VMC with whatever you want. You?re VMC. Finding an examiner to ?pretend? you are shooting an ILS is above my paygrade. Won?t even guess how that conversation will go. Triple GPS has no weight in the approach world if the FAA hasn?t approved it for IFR utilization. It will get you down if you?re in trouble. It may be 4 times safer, but it?s not legal.

The VAL units, or Garmin 300, or any other certified GPS is definitely legal, and safe, if equipped properly. It is NOT legal right now to, in IMC, shoot a GPS approach with just the GRT IFR package if it doesn?t have a certified navigator feeding it. It is perfectly legal and safe to shoot in IMC ILS, VOR or ILS with a VAL if properly installed. The 650/750 etc. offer better situational awareness but that doesn?t mean it?s safer than older equipment.

You comfort level with the other instruments required is up to you as long as your aircraft has the minimum equipment.
Any of us flying in the 60?s on have flown IFR using old school steam gauges and ADF?s and VOR?s felt perfectly safe.

Keep on doing what you?re doing by asking and learning. It?s the best insurance there is.
 
Flying an NDB, VOR, LOC approach using inertial/GPS (FMC technically) is a legal, and trained approach in the 121 world. You usually have to have raw data displayed, and referenced, approach dependent. I have done many hundreds in the last 10 years, outside of CONUS, for 3 different carriers. GRT and MGL seem to be going down this path. I asked one of the "other two vendors", and I got the sense they needed to talk to their lawyers.

I am not planning on certifying my build to be IFR, but I will absolutely practice using my GRT EFIS to do just this, in case of emergency and/or the weather is a lot worse than forecast.

This might be the future for low cost IFR. Garmin introducing a much cheaper navigator this year has me thinking they know it is coming as well.

Not legal yet, but who knows. A NAV radio, and a WAAS GPS EFIS make a pretty good combo.
 
1. I was indeed referring to http://grtavionics.com/home/efis-systems/horizon-hxr-efis/ifr-approach-option/ :

Can I legally fly an IFR GPS approach in non-emergency conditions in my experimental aircraft?

This is a legal question that we are not qualified to address. We make no claim regarding the legality of our GPS approach when intentionally flying in IFR conditions.

2. "There is no such thing as soft IFR...one day you will be caught." Well, in this case, there is also no such thing as VFR, either. One day you will be caught in IFR. Or feasible IFR...one day you will be caught with fog down to zero. yes, I want to prepare well for my IFR test in my airplane, but I do not plan to fly in the soup unless it is greatly above where I know I can fly.

3. My problem right now is equipping my airplane reasonably. I want to do pass the IFR checkride, so that afterwards, I can fly off when there is a thin cloud layer on the airport at 1000'. what makes sense for this scenario? I am guessing that VOR/ILS/GS will go the way of the Loran in a decade or two, because they are just too expensive to maintain in smaller airports; and putting the relevant into a modern airplane for my kind of use seems wasteful. BUT, is VOR stuff really what I need to do here?

I used to work for GRT, and now I work for Garmin. I can't really comment on avionics online... (namely, it's not my job anymore :) ) But I will say this: you would be very wise to listen to the great advice given here by Widget, Stripes and Bob Turner. These guys have been flying GRT equipment IFR for many, many years. They are professionals. They know their equipment very well and they know what it takes to fly their RV safely in the weather. Personal minimums are great, but you and your plane need to be prepared for the worst. Otherwise, you don't have a "Light IFR" airplane. You have a VFR airplane equipped for an emergency let-down.
 
Here is a good link.
https://www.eaa.org/eaa/aircraft-bu...ions/equipping-a-homebuilt-for-ifr-operations

If you are qualified and current Inst rated Pilot who flies actual IMC... and your RV is equip for IFR per part 91 great. (Gyro = mechanical or electronic) Is it safe is up to PIC... AC 20-138A or not. I am sure the FAA will insist a TSO GPS and current IAP data is mandatory. Do you have backup Inst and electrical power?

I gather some VFR pilots think their EFIS will save their bacon if " they get in trouble" TSO or not, they are foolish. It might but also will likely result in accidents due to LOC due to continuing Flt into IMC.

Do people fly IFR illegally. Yep they have been doing it for a 60 years, way before EFIS or GPS. Some folks fly IMC without filing IFR Flt plan and make up their own IAP. Do some pilots flying IFR and GPS approaches without TSO GPS? I'm sure. Not a good idea in my opinion.

I flew IFR +20 years ago in GA planes with steam gauges but had a Garmin 195 hand-held GPS which had instrument approach data!!! I never used it for sole source NAV but GPS was a great reference for situational awareness. If you put in a VOR/LOC/ILS/DME/MB into your RV and get plates you can fly IAP all day (at least at airports with these approaches). I don't say ADF/NDB because those have gone the way of doah-doah bird, all most all replaced by GPS. The good news ILS Cat I is lowest Mins still than any GPS approach WAAS or not. Bad news is GPS is almost becoming mandatory to fly IFR. GPS approaches are prolific. If all you have is GPS you are also limited.

Can a non-STC EFIS display the TSO GPS data / map. Yes is my conclusion for experimental aircraft only. Certified plane, no you need the STC. Many "experimental" EFIS are now approved STC for GA planes. So that should give us some optimism. However 15 years ago when the Dynon D10 came out it was not so clear if these wonders were reliable "gyros"....

Also if your life depends your "gyros" mechanical or electronic better have redundancy. STC EFIS in GA requires backups... You still see pilot static instruments. Probably a good idea we follow AC 20-138A and TSO required or not.
 
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Several sage observations in this thread. A question of my own:

A VHF nav unit is often suggested as an economical path to the part 91 requirements for IFR.

Since the 75Mhz marker systems which had been an essential part of the ILS/LOC approach are now gone, that would leave a non-TSO GPS as the only practical substitute for the marker locations which are now DME positions. Is that OK?

Ron
 
I applaud your concept of personal minimums, but remember you will never be more proficient than the day after you pass your IFR check ride (to a degree).

lol that reminds me of the first time I had to fly a for-real PAR down to 100' minimums at KEF (over a year after passing my IFR checks). I admit that may be an exception to your rule, but I agree if you are flying a LOT of IFR (like you do during training) you do get a lot better.
 
Several sage observations in this thread. A question of my own:

A VHF nav unit is often suggested as an economical path to the part 91 requirements for IFR.

Since the 75Mhz marker systems which had been an essential part of the ILS/LOC approach are now gone, that would leave a non-TSO GPS as the only practical substitute for the marker locations which are now DME positions. Is that OK?

Ron

I'm hardly the most knowledgeable here, but it is my understanding that if the marker beacon identifier is represented in the IFR legal GPS as a nav point (they aren't all, or weren't at one time) then "over the fix" is legal to be determined by GPS. If it just says "MB" on the chart then it may not be in the GPS; if it has an identifier and the GPS "recognizes" the identifier, then you can use GPS to navigate to it.
 
/G

To get the benefits of GPS (filing direct, etc.) on an IFR flight plan (even enroute) you have to file /G and filing /G means that you have the FAA approved equipment to fly the plan you filed. Since the GRT "IFR" option is not certified I don't believe you can file /G on a flight plan.

Other than shooting a few individual approaches (not under the control of ATC on an IFR flight plan) I don't see how useful this option could be.

When getting my Instrument Rating we always filed IFR in the system to learn how the system operates even under VFR conditions. I had GRT equipment in my RV at the time but rented a C-172 to get the rating and appropriate experience with a certified GPS navigator. I don't believe you can do this type of training (file /G) with a non-approved navigator.

Andy
 
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lol that reminds me of the first time I had to fly a for-real PAR down to 100' minimums at KEF (over a year after passing my IFR checks). I admit that may be an exception to your rule, but I agree if you are flying a LOT of IFR (like you do during training) you do get a lot better.

Wings of Gold ARE the exception to the rule, shipmate! :)
 
I could have been a bit more clear.
Equipping with a radio like a Val nav unit to cover the legalities of IFR operation is often suggested. It ties in really nice to a G5 for VOR/LOC/GS. A 2nd G5 gives you an HSI. Since I got my instrument ratings well before GPS arrived on the scene, I could be perfectly happy and even competent with this lavish arrangement in an IFR environment.

But for ILS, no Middle Marker any more (the only one I would really miss). I assumed that the previous location of the marker would be designated by a DME. How to get around that legally?

So, I have looked at a few approach plates now and I am somewhat surprised. The outer marker is a radar or vor intersection and the middle marker is gone and replaced by - nothing. RAL and CNO are local examples.

So, in these cases, It looks like we're good-to-go part 91 legal. - IFR without a TSO'ed GPS navigator $$$. And of course, one can monitor the flight and approach with any GPS nav device.

Re PAR: Yes PAR approaches way back with students at a local bomber place. Seemed easy with a Cessna. With an F4 it might have been a challenge.

Ron
 
I will be shocked if the "legal" functions of certified IFR navigators aren't incorporated into EFIS's in a very very short time. Garmin is obviously wanting this to be as far off as possible. Dynon, GRT, and MGL have a vested interest in making it happen as soon as possible.

Probably for enroute IFR legality first. Approaches later.

It is coming.
 
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