Legal IFR with experimental EFIS?

I am planning my panel and have a question which has a direct and significant bearing on what I will install for IFR.

I am considering a SL 30 nav/com and a GRT sport with internal GPS. The type of non certified GPS is probably not important in this question.

For a VOR DME approach, you have to have of course, VOR and DME. Can the distance information from an EFIS with a GPS, or other uncertififed GPS, be used legally?

Can the CDI displayed by the EFIS be used as the only CDI to display localizer and glideslope information, legally?

In other words, would the combination of SL30 and GRT sport light be a legal combination for IFR?

Thanks,

Tony

Info in search

Oh Gosh not this again. Tony, buddy heads up there are some very good, long and detailed threads on this already. Good luck, Have a good week end.

Can the CDI displayed by the EFIS be used as the only CDI to display localizer and glideslope information, legally?

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Yes, you can fly raw data, VOR, LOC or GS from the SL30 and it can be displayed on an "experimental display", aka EFIS, if it has the handshake (protocol). It is legal.

If your GRT EFIS can display DME data from a DME receiver, than great.

"For a VOR DME approach, you have to have of course, VOR and DME. Can the distance information from an EFIS with a GPS, or other uncertified GPS, be used legally?"

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NO

If the plate says DME you needed DME receiver, period, end of story. Don't get GPS approaches and VOR/DME mixed up. IF the plate says "VOR/DME or GPS RWY 23", than yes you can use IFR GPS for that DME fix. The GRT GPS is not IFR approved, so forget it.

The GPS must be a TSO'ed IFR GPS receiver to be used for ANY IFR operation. As you indicate you know the GRT is not TSO'ed. I guess what part of NOT IFR approved is hard to understand? You can NOT fly a VOR/DME without a DME, and you can NOT use a VFR GPS as a substitute legally and officially for any IFR navigation, ever ever ever ever. That is pretty straight forward.

None of the experimental units have IFR TSO'd GPS, period, likely never will. You want an IFR EFIS with IFR GPS integral, shell out $40k for a Chelton EFIS. You can always buy a used IFR GPS for $2000-$3000. You can go whole hog and get one of the new Garmin's with the Com/VOR/LOC/GS/MB/GPS/MAP all in one, $8,000-$14,000. That may be the way to go?

If you just want to shoot ILS, LOC and VOR approaches than the SL30 and GRT will do. The built in VFR GPS can be an un-offical situational aid or help.

thanks George

George, Thanks for your reply. I know that the issue of IFR equipment has been raised before. I think I have read all those threads, as well as some articles on the topic. I wanted to focus my question a little more than the information in the past threads which were more general, at least the ones that I recall.

I want to make sure that I have a clear understanding before I start buying avionics and putting out big bucks.

So, the CDI or HSI on an experimental EFIS is legal. That is a direct answer to one of my important questions and valuable information.

Regarding the second issue, DME....my instrument instructor taught me that a certified GPS distance readout can be a legal substitute for DME. I almost never see DME equipment anymore. It seems that you may disagree with that George, since you said that only DME can provide DME info for a VOR DME approach. I take the point that even if distance information can be legally provided by a GPS, it must be a certified GPS.

I would be interested in the observations of those of you who are equipped with a nav radio like the SL30 and experimental EFIS combination. Do you find it too limiting, would you do it differently next time?

IFR GPS for DME - yes

tonyjohnson said:

Regarding the second issue, DME....my instrument instructor taught me that a certified GPS distance readout can be a legal substitute for DME. I almost never see DME equipment anymore. It seems that you may disagree with that George, since you said that only DME can provide DME info for a VOR DME approach. I take the point that even if distance information can be legally provided by a GPS, it must be a certified GPS.

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http://www.aopa.org/whatsnew/newsitems/1999/991213gps.html

This says that IFR Certified GPS can be substituted for DME. Read it all, though. There are some gotcha's.

While it is technically true that a horizontal distance is not equal to a slant distance (GPS, DME respectively), the policy is clear. At least AOPA and I think so.

I hope so

Cus I been using my 430 to provide DME all the time...and my checkride examiner even watched me do it....At least I think he was watching me...

Frank

tonyjohnson said:

For a VOR DME approach, you have to have of course, VOR and DME. Can the distance information from an EFIS with a GPS, or other uncertififed GPS, be used legally?

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For VOR/DME approaches, No.

tonyjohnson said:

Can the CDI displayed by the EFIS be used as the only CDI to display localizer and glideslope information, legally?

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Yes.

tonyjohnson said:

In other words, would the combination of SL30 and GRT sport light be a legal combination for IFR?

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Yes for VOR/LOC approaches. No for VOR DME GPS approaches. MHO.

gmcjetpilot said:

If the plate says DME you needed DME receiver, period, end of story. Don't get GPS approaches and VOR/DME mixed up. IF the plate says "VOR/DME or GPS RWY 23", than yes you can use IFR GPS for that DME fix. The GRT GPS is not IFR approved, so forget it.

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Well not exactly. An IFR (enroute or approach certified) GPS may substitute for a DME.

gmcjetpilot said:

The GPS must be a TSO'ed IFR GPS receiver to be used for ANY IFR operation. As you indicate you know the GRT is not TSO'ed. I guess what part of NOT IFR approved is hard to understand? You can NOT fly a VOR/DME without a DME, and you can NOT use a VFR GPS as a substitute legally and officially for any IFR navigation, ever ever ever ever. That is pretty straight forward.

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Again, not exactly. If you are under radar coverage and the controller allows, you could use a handheld, non-certified GPS, etc. to navigate direct to a fix. The key here is that you are under radar coverage. Controllers do this all the time. Even though you are NOT /G, controllers frequently ask "can you navigate direct to XYZ" doesn't matter how since you are on radar. This is just to address that "ANY IFR operation" comment.

gmcjetpilot said:

None of the experimental units have IFR TSO'd GPS, period, likely never will. You want an IFR EFIS with IFR GPS integral, shell out $40k for a Chelton EFIS. You can always buy a used IFR GPS for $2000-$3000. You can go whole hog and get one of the new Garmin's with the Com/VOR/LOC/GS/MB/GPS/MAP all in one, $8,000-$14,000. That may be the way to go?

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There is nothing about the Chelton (or other EFIS, except maybe the G900/G1000 with their integral TSO GPS) that makes it "an IFR EFIS." Neither the certified or experimental unit includes an integral IFR GPS. Both offer the option of the Freeflight IFR GPS, but if you are going to spend the money for that, you would be better of with a standard GNS-430/480 GPS. Are you seriously suggesting folks buy a 40K Chelton and the attach it to a cheap GPS? A better suggestion would be to just get a GNS-430/480 and attach it to whatever EFIS you want; experimental or other. Then you would be IFR legal for ALL approaches.

An SL-30 is about $4000, a GNS-430W is about $8000. Get the 430W, attached it to whatever EFIS you want and you will be all set for ALL approaches.

SL-30 is a much more capable radio than the 430 sans GPS. I really still like the GX-50/60 series GPS with the SL30, they work really well together, and the GX60 is dead simple to use.

?I guess what part of NOT IFR approved is hard to understand?? George that?s a harsh statement.

We are building experimental planes so I think it?s a valid question to ask whether we need certified IFR equipment or not. How many other parts of our aircraft are not certified? Engines often are not, airframe isn?t, almost any other certified part you can think of can be substituted with a non certified part. Ignitions, alternators, wheels, brakes, and yes even avionics . . . really every other part except IFR equipment????

Experimental seems to have lost it?s meaning on many people. Why is it that we are allowed to test a non-certified car engine in real world flying conditions but not test a non-ifr-certified gps in IFR conditions? I have a 480 and a 396 and I can tell you that more often than not I prefer the display and situational awareness of the 396 over the 480 and I strongly believe both are equally reliable for the type of mild IFR flying that I do.

I haven?t looked into this further so I can?t say for certain but my gut tells me there must be some leeway for using non certified IFR equipment under the experimental umbrella.

Non-IFR certified navigation equipment

Kevin, the line is likely drawn at navigation since to fly IFR the systems must meet stringent requirements. You do not want someone going off of established "error" limits with a handheld GPS that does not perform integrity for example.

I am not the expert on this but I find it hard to believe that non IFR approved (TSO'd ?) navigation equipment can be used for IFR ops.

The exact meaning, or loop hole if you will, in the TSO spec is that the equipment meets TSO "XYZ". So, to be extreme, you could build your own GPS, and could legally use it IFR, as long as you demonstrate that it fully meets all the TSO spec's. Now, of course that means alot of certified testing and paperwork which would not be worth it, but there you go.

I will be using the GRT EFIS with GPS (hopefully RAIM) and later on plan on buying the cheapest used IFR GPS just to meet the letter of the law.

IFR GPS

ronlee said:

Kevin, the line is likely drawn at navigation since to fly IFR the systems must meet stringent requirements. You do not want someone going off of established "error" limits with a handheld GPS that does not perform integrity for example.

I am not the expert on this but I find it hard to believe that non IFR approved (TSO'd ?) navigation equipment can be used for IFR ops.

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The requirements for IFR GPS are quite recent compared to those for VOR and ADF. As a result, they are quite demandingly constructed. It's perhaps an exaggeration with too much faith in FAA to say that it's about accuracy. If it were, the NDB approach would not exist. The regs say clearly how accurate a VOR receiver+CDI must be, but it's hard to imagine a handheld GPS that could not do better. Maybe it's just my failure, but when I looked, I could not even find a TSO standard for an ADF. Who among us, regs aside, would prefer to shoot an ADF approach to following the same exact procedure with a 296? Who among us, regs aside, would prefer to shoot a VOR approach 15 miles from the beacon as compared to using a 296? I repeat: it's not really about accuracy.

That said, there is precious little wiggle room in the IFR GPS standards (many of which, though, are in an AC..) for experimentals except where the owner says "this meets the standard" and can produce some evidence to support the statement. Only in experimentals will the non-TSO'd device offer that opportunity. In the near future, however, look for GRT to offer a non-TSO'd "IFR GPS" add-on for the Horizon series EFIS's. This will be where the grey area will be found. I am personally certain that will generate much more debate. Citing the requirements is beyond the scope of this reply.

"Kevin, the line is likely drawn at navigation since to fly IFR the systems must meet stringent requirements. You do not want someone going off of established "error" limits with a handheld GPS that does not perform integrity for example."

My point seems lost on you. Why is it not safe to fly IFR with say a 396 / non-ifr-certified gps but perfectly fine to fly IFR with an old automotive engine that I picked up out of the junk yard.

If I'm going to fall out of the IFR sky why worry about just the gps? why not the engine in my plane that could konk out, or the efis that could go flaky or every / any other part of the plane.

On the surface I think if an experimental builder got ticketed for using a 396 for IFR he could have the citation beat in a second. There is no rhyme or reason to the logic of the argument that the plane could be a bucket of rusty bolts but it's safe / legal to fly IFR because the nav equipment is certified.

I think I would just say my 396 meets the standard. I'll take it up for a flight and do the same gps approach test phase that you have to do when you want to get your 430 approved for IFR. There's my declration and proof.

Like I said this day in age we treat our planes more like certified aircraft then the experimentals that they truly are.

Not

kevinsky18 said:

"..

On the surface I think if an experimental builder got ticketed for using a 396 for IFR he could have the citation beat in a second. There is no rhyme or reason to the logic of the argument that the plane could be a bucket of rusty bolts but it's safe / legal to fly IFR because the nav equipment is certified.

I think I would just say my 396 meets the standard. I'll take it up for a flight and do the same gps approach test phase that you have to do when you want to get your 430 approved for IFR. There's my declration and proof.

Like I said this day in age we treat our planes more like certified aircraft then the experimentals that they truly are.

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As much as I like your thinking, it won't wash. The handheld does not meet the standard because it does not (no RAIM, no missed approaches, no CDI, no annunciators, etc.). It's not just accuracy. The FAA is not responsible for making all aspects of flight equally safe or equally risky. Your logic would doom the experimental category before it would allow IFR use of the handheld GPS.

And to think that laws, regulations and judges can be overcome with logic, reason and fairness is pretty naive, don't you think? I'm not trying to flame you. Heck, I'm the one the others get mad at when I tout the qualities of the '496. I'm just trying to keep it real. No matter how good a handheld is, it's not legal for IFR GPS and you cannot make it so by saying it is. You can use it for situational awareness and you can stretch that quite a bit if you choose too, but you cannot file "/G". Don't blame me; I'm just the messenger. Or maybe you were just kidding?

Integrity is not trivial

It alerts the pilot when the system should not be used for navigation. A GPS clock runoff will destroy your accuracy and your 396 won't tell you. There was a person on a aviation newsgroup who wanted to use any ole GPS for IFR flight. You just can't explain reality to some folks.

I just "developed" a GPS approach to my airport. I can put it in my Garmin 430 and my Lowrance Airmap 500. I will be flying it in VFR conditions with foggles and a safety pilot just to make a point about issues not related to this thread. Most likely it will be deleted after I try it.

kevinsky18 said:

We are building experimental planes so I think it?s a valid question to ask whether we need certified IFR equipment or not.

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Kevin,

Your are mixing up your FARs. The simple answer to your question is YES.

With engines and airframes, you are only affecting yourself; with a navigational equipment, you are potentially affecting the WHOLE system. Experimental engines and airframes fall into part 21 of the FAR; using navigational equipment in US airspace falls into FAR part 91. While you can operate an experimental registered in part 21, you still have to abide by FAR part 91 operating parameters-part 91 doesn't care that your engine and airframe is experimental--just that the equipment you are using to move through the airspace adheres to part 91 operating limitations. Just as you still have to do a 24 month altimeter/transponder check with an experimental, you still need to abide by the TSO for IFR GPS.

kevinsky18 said:

I haven?t looked into this further so I can?t say for certain but my gut tells me there must be some leeway for using non certified IFR equipment under the experimental umbrella.

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Truthiness alert!

For IFR GPS, the TSO's are pretty clear; 129a with RAIM for non-WAAS and 146a for with F/DE WAAS IFR GPS. You file /G with a portable or non TSO'd GPS even in an experimental and get busted, you are screwed and there is no easy out.

Good post! Like William says, it's the system that's being affected. This is the same reason that the ELT and Transponder have to meet TSO requirements.