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Foreflight Legal for IFR Navigation?


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I was chatting with a pilot about ADSB compliance and what equipment we both need. I mentioned that it's gonna be especially challenging for him as he does not have a WAAS GPS source. He said he does, the stratus 2 for foreflight. He then went on to tell me how great it is and that he doesn't need anything in the panel. I brought up IFR and he assured me that the foreflight/stratus is legal for IFR. My response was "as an efb, just for displaying the charts." But he swore it is legal for navigation including flying approaches. My response again, "advisory for situational awareness only" and he swears entirely for navigation with no panel mounted gps. Then I said, "maybe for experimental only." But he says even for type certificates like his Skyhawks. He spoke with absolute confidence and said to look it up, even bet me lunch.

Maybe I'm getting old but I can't phathom how the FAA would ever allow something cheap to be legal/primary. I suspect he is confusing the ability to use VFR GPS for enroute vectoring with ATC. I can't imagine any way how a portable stratus/foreflight could be legal for shooting GPS approaches or as an ADSB-Out WAAS source. Is there any sliver of a chance that some new interpretation or certification makes this so? Or can anyone cite me the regs that would prove this to be wrong.

Based on 91.205d2, you'd think he could be right: "(2) Two-way radio communication and navigation equipment suitable for the route to be flown."

What determines that a 430W is suitable and stratus/foreflight isn't?

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1 minute ago, 201er said:

I was chatting with a pilot about ADSB compliance and what equipment we both need. I mentioned that it's gonna be especially challenging for him as he does not have a WAAS GPS source. He said he does, the stratus 2 for foreflight. He then went on to tell me how great it is and that he doesn't need anything in the panel. I brought up IFR and he assured me that the foreflight/stratus is legal for IFR. My response was "as an efb, just for displaying the charts." But he swore it is legal for navigation including flying approaches. My response again, "advisory for situational awareness only" and he swears entirely for navigation with no panel mounted gps. Then I said, "maybe for experimental only." But he says even for type certificates like his Skyhawks. He spoke with absolute confidence and said to look it up, even bet me lunch.

Maybe I'm getting old but I can't phathom how the FAA would ever allow something cheap to be legal/primary. I suspect he is confusing the ability to use VFR GPS for enroute vectoring with ATC. I can't imagine any way how a portable stratus/foreflight could be legal for shooting GPS approaches or as an ADSB-Out WAAS source. Is there any sliver of a chance that some new interpretation or certification makes this so? Or can anyone cite me the regs that would prove this to be wrong.

Based on 91.205d2, you'd think he could be right: "(2) Two-way radio communication and navigation equipment suitable for the route to be flown."

What determines that a 430W is suitable and stratus/foreflight isn't?

Nothing could be further from the truth!

You need a TSO's GPS navigator to navigate IFR within the NAS period. If I recall correctly its TSO C129 for non-waas supplemental nav and TSO C145 or C146 for WAAS sole source navigation. Even experimental aircraft have to be install such devices to fly IFR. Tell him to call his local FSDO or ask anyone on his local FAASTeam group.

he owes you lunch :)

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11 minutes ago, kortopates said:

Nothing could be further from the truth!

You need a TSO's GPS navigator to navigate IFR within the NAS period. If I recall correctly its TSO C129 for non-waas supplemental nav and TSO C145 or C146 for WAAS sole source navigation. Even experimental aircraft have to be install such devices to fly IFR. Tell him to call his local FSDO or ask anyone on his local FAASTeam group.

he owes you lunch :)

I'm going to try to play devil's advocate (or lunch better's advocate in this case) because I would be really curious if he is in any way right. From what I understand, TSO applies to panel installed avionics and would not govern portables. FAR 91.205d only says you as an airman are required to have navigation equipment suitable to the flight." So while non-tsoed equipment may not be legal to install/mount in your airplane, what regulation states that it is required for instrument navigation or GPS WAAS approaches? What regulation states your GPS has to be panel mounted and cannot be portable in the first place?

I'm not being fecicious, I'm just feeling kind of dumb not being able to prove what would seem obvious. Who can dig up the proof?

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6 minutes ago, 201er said:

I'm going to try to play devil's advocate (or lunch better's advocate in this case) because I would be really curious if he is in any way right. From what I understand, TSO applies to panel installed avionics and would not govern portables. FAR 91.205d only says you as an airman are required to have navigation equipment suitable to the flight." So while non-tsoed equipment may not be legal to install/mount in your airplane, what regulation states that it is required for instrument navigation or GPS WAAS approaches? What regulation states your GPS has to be panel mounted and cannot be portable in the first place?

I'm not being fecicious, I'm just feeling kind of dumb not being able to prove what would seem obvious. Who can dig up the proof?

See AC 90-100A. Its spells out what equipment you need to fly what, from DME to GPS including which equipment allows you to fly what in the NAS e.g., Q-routes,SIDs, STARs etc, Everything it list is in reference to a TSO standard. Which is why a portable equipment is never approved for navigation in the NAS; its only supplemental, even VFR. 

Edited by kortopates
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8 minutes ago, kortopates said:

See AC 90-100A. Its spells out what equipment you need to fly what, from DME to GPS including which equipment allows you to fly what in the NAS e.g., Q-routes,SIDs, STARs etc, Everything it list is in reference to a TSO standard. Which is why a portable equipment is never approved for navigation in the NAS; its only supplemental, even VFR. 

I think that AC settles that matter quite well. The only question then is, are you sure there isn't some new AC or LOI that supersedes allowing for portables recently?

Also, how do users of non-certified GPS get away with filing "VFR gps" in remarks and getting direct routes? Is this a loophole, ATC turning a blind eye, or downright allowed by some other reg?

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6 minutes ago, 201er said:

Also, how do users of non-certified GPS get away with filing "VFR gps" in remarks and getting direct routes? Is this a loophole, ATC turning a blind eye, or downright allowed by some other reg?

You can fly VFR direct using dead reckoning, can't you? ATC is only giving you traffic advisories time permitting. You are not bound to stay on your stated course. You can divert around clouds to your hearts content so using your phone's GPS is perfectly fine. VFR!   

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Just now, Bob_Belville said:

You can fly VFR direct using dead reckoning, can't you? ATC is only giving you traffic advisories time permitting. You are not bound to stay on your stated course. You can divert around clouds to your hearts content so using your phone's GPS is perfectly fine. VFR!   

(I'm talking about under IFR)

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I think that AC settles that matter quite well. The only question then is, are you sure there isn't some new AC or LOI that supersedes allowing for portables recently?

Also, how do users of non-certified GPS get away with filing "VFR gps" in remarks and getting direct routes? Is this a loophole, ATC turning a blind eye, or downright allowed by some other reg?

 

Mike -- I "got away" with using "VFR GPS" in the remarks section back in the 90s because I was in radar coverage. Often it something like "fly heading 320°, when able, direct GEE". The only problem was GEE was 180 miles away. As long as I was I radar coverage, I would get it. They knew the only way I could get there was the GPS.

 

What I would never get was some GPS waypoint. It was always something my /A could fly.

 

 

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7 minutes ago, 201er said:

I think that AC settles that matter quite well. The only question then is, are you sure there isn't some new AC or LOI that supersedes allowing for portables recently?

Also, how do users of non-certified GPS get away with filing "VFR gps" in remarks and getting direct routes? Is this a loophole, ATC turning a blind eye, or downright allowed by some other reg?

Its not a loop hole. Firstly, these days, no matter what you filed as (e.g., /A or /G) or what you put in the remarks, controllers will assume any IFR aircraft is a /G and will offer direct when they can. Secondly, Its up to the pilot to tell the controller they can't accept that since they don't have the navigational equipment (IFR approved GPS) to support it in the panel. But the pilot with a VFR only GPS can legally accept a "vectors" in lieu of the direct which essentially means the pilot may need more vectors along the way.

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I suspect this is only going to get blurrier as time goes on until the whole "non-TSO" equipment thing for GA gets sorted out, which will probably take a while.   While I suspect the statements of the gentleman in question are wrong, the truth is that it is often the case that far better information is available on an EFB than on anything in the panel in the airplane.   A $150 stratux with the $35 waas GPS receiver coupled to the EFB, plus the latest downloaded charts and plates (could easily be map and/or plate data downloaded the same day or within hours on the EFB), could easily outperform many GPS equipped panels from that perspective.

I know it's not exactly apples and apples, but there is a bit of a point to what the guy said, even if he wasn't technically correct.

 

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It is impossible for Foreflight to get a TSO or FAA approval because Foreflight is an application than can run on multiple non FAA approved devices. Tablets and cell phones have no FAA approval. The host device operating system and Foreflight has to prove that it complies with DO-178B. https://en.wikipedia.org/wiki/DO-178B. Only the device manufacturer can prove compliance. And I don't think that Apple or Samsung would be willing to spend any money to get FAA approval.

José

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12 minutes ago, EricJ said:

I suspect this is only going to get blurrier as time goes on until the whole "non-TSO" equipment thing for GA gets sorted out, which will probably take a while.   While I suspect the statements of the gentleman in question are wrong, the truth is that it is often the case that far better information is available on an EFB than on anything in the panel in the airplane.   A $150 stratux with the $35 waas GPS receiver coupled to the EFB, plus the latest downloaded charts and plates (could easily be map and/or plate data downloaded the same day or within hours on the EFB), could easily outperform many GPS equipped panels from that perspective.

I know it's not exactly apples and apples, but there is a bit of a point to what the guy said, even if he wasn't technically correct.

 

I would never expect non-TSO'd equipment to be legal for IFR navigation in the NAS. Not a chance. Just like what you are seeing with ADS-B Out manufactures trying too and the FAA insisting that they have to have TSO'd WAAS position source for valid ADS-B out compliance.

Using your EFB with ADS-B In with wx & traffic for enhanced situational awareness is whole another topic and of course and is a big plus, but to say it outperforms GPS equipped panels with the same capabilities is naive. Everything you see on the iPad has been available on panel equipment for much longer and is more reliable. The ipad just brings it into your cockpit for a fraction of the cost.

Edited by kortopates
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Just now, kortopates said:

I would never expect non-TSO'd equipment to be legal for IFR navigation in the NAS. Not a chance. Just like what you are seeing with ADS-B Out manufactures trying too and the FAA insisting that they have to have TSO'd WAAS position source for valid ADS-B out compliance.

Using your EFB with ADS-B In wx 7 traffic for enhanced situational awareness is whole another topic and of course is a big plus, but to say it outperforms GPS equipped panels with the same capabilities is naive. Everything you see on the iPad has been available on panel equipment for much longer and is more reliable. The ipad just brings it into your cockpit for a fraction of the cost.

It's been a continuing thing for a long time that since the TSO process takes a long time that the equipment is obsolete by the time it is approved.   Performance-wise, there's no difference in a panel mounted WAAS GPS for information display than there is in an EFB getting WAAS GPS info from a $150 stratux sitting on the glareshield, not to mention traffic and weather.   Many IFR GA airplanes don't have a panel GPS at all, and many that do don't have WAAS or a decent graphical display.  From that standpoint, the EFB info will be better.   Many times I've had TIS-B traffic alerts on my EFB and the ADS-B-in panel traffic never said boo about it.   The panel electronics are just not a clear winner in many cases.

That's my only point, that an EFB may easily be providing better info than whatever is in the panel, just like a lot of experimental airplanes have panels that are superior in many ways to TSO'd equipment, just because it is more recent and has the benefit of newer, better technology in a more agile market.    With a cheapie external AHRS and a $35 waas GPS receiver, you can have a very effective and useful EFIS and GPS nav system on a portable tablet or phone display, and it may all wind up being a lot better than whatever is in the panel on many airplanes (and certainly not all).   The spread in technical performance between what is available in cheap, portable electronics and what qualifies as acceptable in the regs has already closed and overlapped.   The technology doesn't have to catch up, the regs do, and that usually takes a long time.

This is from somebody who used to develop avionics for airliners, so I'm familiar with the development, verification, test, and regulatory standards and hurdles.   

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14 minutes ago, EricJ said:

Performance-wise, there's no difference in a panel mounted WAAS GPS for information display than there is in an EFB getting WAAS GPS info from a $150 stratux sitting on the glareshield, not to mention traffic and weather.

I have to disagree.  There's a huge difference between my GNS-430W and the Stratux that I soldered together in my living room.  I don't trust myself to assemble circuit boards as well as a well established quality-controlled process, and I don't trust the open source community to rigorously find and fix all the bugs that could cost me my life in the clouds.

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4 minutes ago, gsengle said:

There is a huge difference. Talk to me about RAIM? RNP?

No that gear isn't as precise or reliable.


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The net effect for differences in actual navigation as would be done from an EFB are very small compared to the differences in navigation capability of a non-GPS IFR airplane and somebody with a well-disciplined EFB.   And yet one is held as a higher standard than the other (i.e., approved vs not), which simply isn't the case in practice.

Believe me, I fully appreciate the technical differences, but I also recognize the disparities in the practical applications.   A 50-year old airplane with original aging analog radio navaids is not "better" than a modern EFB with good external inputs (or even without, IMHO), but one can be approved and the other not.   This is not an easy thing to rectify from a regulatory point of view, but I think the gap should be a lot narrower than it is.

 

Just now, 3914N said:

I have to disagree.  There's a huge difference between my GNS-430W and the Stratux that I soldered together in my living room.  I don't trust myself to assemble circuit boards as well as a well established quality-controlled process, and I don't trust the open source community to rigorously find and fix all the bugs that could cost me my life in the clouds.

I think you're pointing out potential hardware reliability issues rather than performance issues, which was not part of my point.   I don't know if there is any public MTBF data on relevant panel mounted avionics vs typical tablets, but I wouldn't be surprised if they're similar.

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35 minutes ago, EricJ said:

It's been a continuing thing for a long time that since the TSO process takes a long time that the equipment is obsolete by the time it is approved.   Performance-wise, there's no difference in a panel mounted WAAS GPS for information display than there is in an EFB getting WAAS GPS info from a $150 stratux sitting on the glareshield, not to mention traffic and weather.   Many IFR GA airplanes don't have a panel GPS at all, and many that do don't have WAAS or a decent graphical display.  From that standpoint, the EFB info will be better.   Many times I've had TIS-B traffic alerts on my EFB and the ADS-B-in panel traffic never said boo about it.   The panel electronics are just not a clear winner in many cases.

That's my only point, that an EFB may easily be providing better info than whatever is in the panel, just like a lot of experimental airplanes have panels that are superior in many ways to TSO'd equipment, just because it is more recent and has the benefit of newer, better technology in a more agile market.    With a cheapie external AHRS and a $35 waas GPS receiver, you can have a very effective and useful EFIS and GPS nav system on a portable tablet or phone display, and it may all wind up being a lot better than whatever is in the panel on many airplanes (and certainly not all).   The spread in technical performance between what is available in cheap, portable electronics and what qualifies as acceptable in the regs has already closed and overlapped.   The technology doesn't have to catch up, the regs do, and that usually takes a long time.

This is from somebody who used to develop avionics for airliners, so I'm familiar with the development, verification, test, and regulatory standards and hurdles.   

I guess we're going to have to agree to disagree. I do hear what you're saying about with regard to the challenges in meeting regulatory requirements.- I agree with most of that. And I am optimistic we'll see things improve greatly with performance based requirements discussed in the part 23 re-write versus the past overly specific requirements that really OEM how to build them. I agree with all that. I'll also agree that some of the hardware components being incorporated into portable solutions made ot industry standards is rivaling TSO'd hardware in quality.  But you seem to imply we don't need the underlying TSO requirements and there I don't agree. Take the C145/C146 TSO requirements for WAAS IFR GPS. So what if you have a WAAS stratux receiver operating at whatever hz rate it is. Do you really feel as safe if the s/w lacks all the integrity checking s/w required by the TSO that monitoring CEPs and looking ahead on your approach to verify it will have adequate signal and if not compares what it has and what it predicts to what it requires for each approach type and downgrades the approach minimums you can fly. Its all the reliability engineering, systems testing integrity checking that makes the systems superior; in fact its not eveb comparable. Not all iPad apps even have good mechanism of alerting you of poor position solution. 

These days its getting more and more rare that an airplane doesn't have something like a GNS430W in it - even if its only a C150.  But granted there are plenty aircraft that still do not.

I respect your avionics development background and would love to discuss this at length over a beer to better understand your perspective, but I also come from similar background as chief systems engineer of large government system programs. I began my career on flight planning systems for the military but also did a lot of commercial projects as well.  

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And yet VOR/NDB are still regarded as robust systems. Unusable radials, drift, calibration errors, other issues that are beyond my level of sophistication... the cheapest of the cheap gps systems still seems to be more robust, accurate, and reliable, wouldn't you say? Why is it ok to fly an NDB or timed VOR approach but not use some sort of portable gps?

Edited by 201er
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I use both the FAA certified/approved equipment and the iPad portable stuff.

I suspect that the internal GPS driving my EFB moving map is made by the same company that the certified unit uses. So, Yes the hardware is just (if not more) capable than the FAA approved, IFR legal GPSs are.

As stated above, the big difference is the firmware and software in those portable units may not perform to the same accuracy at some point in time. When they work they work and are great but my experience has been that they fail when I need them most.

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1 hour ago, 3914N said:

I have to disagree.  There's a huge difference between my GNS-430W and the Stratux that I soldered together in my living room.  I don't trust myself to assemble circuit boards as well as a well established quality-controlled process, and I don't trust the open source community to rigorously find and fix all the bugs that could cost me my life in the clouds.

You soldered together a stratux?  Why? 

Just buy the raspberry pi and stick the USB ADSB receiver and gps puck in.  No need to solder anything: it's a very easy "build."

not saying its better than a 430- but the only tools required to "build" a stratux are your two hands.

Edited by M016576
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What everyone seems to be missing is that the gps in your 430w et al is required in software to do mathematical integrity checking, and understands how accurate it is to what standard at what time in order to know what navigation is approved - do you get the glideslope or not on that RNAV approach...


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