IFR, and IFR into IMC in an E-LSA

[PilotMelch]

Hi everyone. I have been trying to find a definitive answer to what appears to be a common question. Can I equip my E-LSA (recently converted from an SLSA) to fly IFR, and more importantly IFR into IMC. Here's some key info:

• My Plane already has dual HDX panels, with Dynon AP, Dynon Transponder and ADSB-OUT, Dynon ADSB-IN, Dynon GPS-2020, single ADAHRS, single Comm - All Dynon avionics except I also have a Garmin 796 with its own ADSB-IN and Sirius/XM weather (GDL52) in an AirGizmos mount in the panel.
• I want to add a Garmin GPS 175 Navigator and Dynon ARINC adapter, plus the Dynon EFIS-D10A for backup (or the Garmin G5) - this will seem to meet the requirements for acceptable navigation and a third attitude instrument
• My new E-LSA Operating Limitations state specifically that I can use it for Night VFR and IFR if equipped per 91.205(c) and 91.205(d) respectively. There is no stated prohibition on flight into IMC. I asked the DAR to include this language and he said they always do now anyway (I also believe anyone could get it in their E-LSA Operating Limitations after the originals were issued by simply contacting a DAR to reissue Operating Limitations with it included).
• It was my understanding that the issues with IFR in an SLSA (which mine is no longer) are with SLSA's Manufacturer's stated limitations, and what they will allow. Even if the SLSA's Operating Limitations allow it if properly equipped (mine did, I asked that DAR to include the verbiage as well) it's unlikely the manufacturer would issue an LOA to equip it for IFR anyway. But I'm no longer beholden to them, now that I've converted the certificate to an E-LSA.
• I understand that the SLSA ASTM standards state IFR, but no IMC, but I can't find that in any FAR's (or am I missing something?). Nevertheless, my plane is no longer an SLSA and is now a bonified E-LSA, where I can choose to use a coat hangar for landing gear if I so choose (not that I would mind you, that would be stupid).
• My engine is currently a Rotax 912ULS, a non-certified engine. On this, I have two questions.
  • 1) does this matter? Again, it's an experimental now. Is there an FAR requiring a certified engine for IFR, or IFR into IMC? I'm pretty sure I've heard this claim in the past with regards to EAB, but I know of several EAB's flying full IFR on non-certified engines, so what's the legal reality here, and are there specific FAR's that can be pointed at?
  • 2) I plan to install an Edge Performance EFI kit on this engine. I believe this means it is no longer a Rotax engine (or is it) - anyway it's not fully a Rotax engine, so Rotax doesn't have any say anyway, right? Technically it was never a fully Rotax engine; the manufacturer had it's own exhaust system, modified the cooling and oil system, etc., as many SLSA manufacturers do.
• I am an Instrument rated Private Pilot, not a Sport Pilot. So I'm good to go.

All I can find are answers related to SLSA (not applicable to an E-LSA, right?), or that Rotax doesn't allow IFR (not sure that matters to begin with, and especially in my case), and references to the ASTM standards regarding no IMC (again, the ASTM standards are for manufacturers making SLSA's, and thus by extension the original certificate for an E-LSA, but not after that, right?)

I sat in on the live stream Dynon webinar yesterday for the EAA virtual event. The two guys from Dynon/Advanced responded to a participant's question about equipping an RV-12 for IFR, and the answer they both gave was that it had to be registered as an EAB, not E-LSA. I have respect for these guys, but I think they are incorrect, at the very least incorrect about equipping an RV-12 as an E-LSA for IFR. I agree, when getting the original E-LSA certificate it has to be bolt-for-bolt identical to the SLSA prototype, which isn't IFR equipped. But, after that, why couldn't he add the IFR equipment (if the Operating Limitations allow, and that's easy to get if it wasn't there originally). There wasn't anything in the question regarding IMC, only IFR either.

So why then did the two Dynon experts state that it had to be an EAB?

Finally, the president of LAMA, Dan Johnson, specifically explains that E-LSA's can have IFR equipment installed and one can fly into IMC if that equipment is current, the pilot is appropriately rated, and current - https://www.bydanjohnson.com/instrument-flying-in-light-sport-aircraft/ - from this article I quote, "In summary, if you are an instrument pilot, and if you are current, and if you have a medical, and if you purchase an aircraft like the Bristell and register it as an ELSA, no regulation prevents you from filing and flying IFR including into IMC." Dan also includes links to other resources and the FAR's.

I'm tired of googling all over and seeing the same old speculations. I want my Dynon-equipped E-LSA to do IFR into IMC (in my case my light plane will only be taken into light IMC, just FYI). I just want to get through thin cloud layers, and fly on top where it is smooth, even if I have to crawl through some clouds to land at my destination. Simple light IFR.

Honestly, if it weren't for the Dynon guys yesterday stating that this gentleman's RV-12 had to be registered as an EAB (versus E-LSA) to be equipped for IFR, I'd already be ordering the Dynon ARINC and a Garmin 175 Navigator, and redesigning my panel.

 

[Spert]

I have no idea about LSA regulations, but in 30 years of flying have never heard of conducting IFR operations with a restriction on going IMC. How would you make this work? VFR you have the freedom to navigate around clouds if encountered. On an IFR flight plan that option doesn’t exist without an alternate clearance. So other than only flying on VFR days (in which case, why bother), how would you guarantee compliance with a no IMC restriction?

 

[airguy]

If your oplims says you are good for IFR while complying with 91.205, that's all there is to it. Comply and fly.

 

[Marc_J._Zeitlin]

Hi everyone. I have been trying to find a definitive answer to what appears to be a common question. Can I equip my E-LSA (recently converted from an SLSA) to fly IFR, and more importantly IFR into IMC.

Yes. See:

Can you fly IFR in an LSA? — General Aviation News

generalaviationnews.com

 

[jnmeade]

I have had two aircraft changed from SLSA to ELSA, and one of them had an amendment to the Operating Limitations. Nevertheless, I am no expert and the following is a layman's opinion.

Operating Limitations are specified in FAA Order 8130.2(letter). The current edition is 8130.2J, but yours may be earlier. Not all the Operating Limitations are applied to each plane. Some are written for jets, for example. Edition 8130.2H had the limitations in Appendix C. J has the limitations in Appendix D.

The more recent editions state that IFR may be permitted if it was permitted in the AOI. I am assuming the AOI is the one issued by the SLSA manufacturer. I don't know but my guess is very few SLSA AOI permitted IFR in IMC. If they did not, then a ELSA derived from an SLSA would be hard pressed to be approved for IFR in IMC, it would seem to me. Read the Order for yourself. If your Operating Limitations were written since 2017, they are probably from 2J, in which case you want to look at D6 and D49, which will also require you check back in Appendix D and also in 91.327(b) 3 or 4.

I believe modifications to Operating Limitations must be done by a FSDO or MIDO; a DAR can not modify Operating Limitations. I say this from personal experience. D4 states this if it is included in the Operating Limitations. Your DAR or FSDO can answer this.

If your Operating Limitations clearly approve IFR, it would be good keep it that way as it seems difficult to get them anymore.

Here is the current Order.

https://www.faa.gov/documentLibrary/media/Order/FAA_Order_8130.2J.pdf

Here are a couple of quotes, but of course you must consult your specific Operating Limitations.

D6 This aircraft may only be operated per the manufacturer’s aircraft operating instructions (AOI), including any requirement for necessary operating equipment specified in the aircraft’s equipment list. Night flight and instrument flight rules (IFR) operations are authorized if allowed by the AOI and if the instruments specified in § 91.205 are installed, operational, and maintained per the applicable requirements of part 91. (6)

D49. Instrument flight operations are authorized if the instruments specified in § 91.205(d) are installed, operational, compliant with the performance requirements of, and maintained per the applicable regulations. All maintenance or inspection of this equipment must be recorded in the aircraft maintenance records and include the following items: date, work performed, and name and certificate number of person returning aircraft to service. (49)

The kicker in D49 is "For limitations 48-50, refer to paragraphs D-4.f of this appendix." It goes back to the AOI.

I guess if I were in doubt about any of this I'd ask the DAR.

Here is a question - what does one do if the DAR made incorrectly stated an Operating Limitation and permitted IFR when the Order does not permit it? Does one pretend it didn't happen, or does one ask the FSDO to correct it? The question, of course, is what would the FSDO do if it found out the plane was operated in accordance with an incorrect or invalid Operating Limitation? I have no clue and I'm not trying to start a discussion.

Keep us posted on what you find out.

 

[PilotMelch]

Operating Limitations are specified in FAA Order 8130.2(letter). The current edition is 8130.2J, but yours may be earlier. Not all the Operating Limitations are applied to each plane. Some are written for jets, for example. Edition 8130.2H had the limitations in Appendix C. J has the limitations in Appendix D.

Ok, I read through the latest 8130.2J Order. Chapter 7 deals with issuing an "Experimental Purpose of Operating Light-Sport Aircraft (§ 21.191(i))". I.e., it deals with issuing an E-LSA certificate.

I'm keeping in mind that this Order deals with the moment in time that the new certificate is issued and not with what happens after that certificate is issued. I believe this is a key point.

In summary, there are currently two ways to get an E-LSA certificate. You either build one from a kit that conforms, bolt-for-bolt, to the manufacture's SLSA prototype, or you begin with an SLSA that remains compliant to the manufacturer's SLSA specification. If you've made any unauthorized modifications (not approved in writing from the manufacturer), then there are further requirements, like testing, or maybe not being eligible at all.

Mine was a compliant, existing SLSA, but another might be a compliant kit-built, getting its first certificate as an E-LSA. The OL's issued do not appear to be different based on this distinction.

The more recent editions state that IFR may be permitted if it was permitted in the AOI.

I saw nothing in what I read that relates to this, or at least nothing related to the AOI or for 21.191(i) certificates. Did I miss that?

I am assuming the AOI is the one issued by the SLSA manufacturer. I don't know but my guess is very few SLSA AOI permitted IFR in IMC. If they did not, then a ELSA derived from an SLSA would be hard pressed to be approved for IFR in IMC, it would seem to me. Read the Order for yourself. If your Operating Limitations were written since 2017, they are probably from 2J, in which case you want to look at D6 and D49, which will also require you check back in Appendix D and also in 91.327(b) 3 or 4.

Yes I believe the AOI being referenced in Chapter 17 refers to the AOI of the manufacturer (either the kit manufacturer or the manufacturer of the existing SLSA). This, I believe, is being referenced only for the DAR to ensure the plane applying for the E-LSA certificate currently complies with this manufacture's AOI before being eligible for the E-LSA certificate.

That said, I didn't see anything in the Order or in my OL's stating that after the E-LSA certificate is issued, I remain bound by this original manufacture's AOI, or that it even applies to anything anymore. I assume that, like with any Experimental, if I make a change to my plane (as I have the right to do) that affects what should be in the AOI, that I make sure my ongoing AOI contains that.

The only reference to an AOI in my OL's is D27, which states, "The pilot may only conduct the flight maneuvers authorized in the AOI. (27)" Again, I believe this is just for the ongoing AOI that I would amend if I change anything that requires it to be amended. Like all OL's, this OL is to an operator of that aircraft about its limitations and states that they can only conduct flight maneuvers authorized in this plane's (current) AOI. This AOI would not, per se, be the manufacture's original AOI, or it would have to say so. Again, if I amend it, "the AOI" becomes the amended AOI. It also only deals with flight maneuvers, not flight conditions, but even if it did, that would only need to be added to the AOI.

If your Operating Limitations clearly approve IFR, it would be good keep it that way as it seems difficult to get them anymore.

Perhaps this is the case, but that doesn't match my experience. Five years ago, when my plane was issued its original certificate (as an SLSA), I requested of the DAR that my OL's include verbiage to allow both Night VFR and IFR if properly equipped. Of course, I knew any subsequent modifications would need to be approved by the manufacturer as well and were probably unlikely. Still, I wanted the OL's there in case I could get manufacture approval. There was no hesitation by the DAR to include them, and all subsequent planes of this type had them as well.

Recently, when I went to convert to an E-LSA, I asked my new DAR (different DAR) for that verbiage, and he said they all include that now. Essentially the verbiage would be there whether I requested it or not (it's in the Order to do so). It also sounded like one could get it upon request if they didn't already have it in their existing OL's, just by requesting it. I had mistakenly thought this meant working with a DAR, but it is clear to me now that such as request would be to the local FSDO.

Still, if someone went to the FSDO to get revised OL's, it makes sense that it would be per the current 8130.2 Order and not the one that was in place when the certificate was issued. Again, the Order deals with the here and now of getting a certificate (and thus OL's), not what happens after that. After the certificate/OL's are issued, what I can/cannot do is governed by the FAR's and what was placed in the OL's.

D6 This aircraft may only be operated per the manufacturer’s aircraft operating instructions (AOI), including any requirement for necessary operating equipment specified in the aircraft’s equipment list. Night flight and instrument flight rules (IFR) operations are authorized if allowed by the AOI and if the instruments specified in § 91.205 are installed, operational, and maintained per the applicable requirements of part 91. (6)

The Order states that D6 applies to 21.190 (i.e., Special certificates, like SLSA). It does not apply to certificates issued under 21.191 (Experimental, like E-LSA or E-AB, etc.), so it isn't in my OL's and doesn't appear that it should be.

D49. Instrument flight operations are authorized if the instruments specified in § 91.205(d) are installed, operational, compliant with the performance requirements of, and maintained per the applicable regulations. All maintenance or inspection of this equipment must be recorded in the aircraft maintenance records and include the following items: date, work performed, and name and certificate number of person returning aircraft to service. (49)

The kicker in D49 is "For limitations 48-50, refer to paragraphs D-4.f of this appendix." It goes back to the AOI.

I do have D48 (Night VFR) and D49 (IFR). They only state that Night VFR and IFR are permitted if properly equipped per 91.205 (c) and (d) respectively, and of course, are maintained and current. No other limitations of conditionals are spoken of, including to any limitation regarding IFR into IMC.

The Order does note for D48 and D49 "For limitations 48-50, refer to paragraphs D-4.f of this appendix.".

D-4.f says "Aircraft with very high risk factors or safety of flight issues must have those factors properly mitigated. Restrict operations to a specified geographical area, and prohibit the carriage of passengers, flight over densely populated areas, and night or instrument flight rules (unless restricted to visual meteorological conditions (VMC)) operations for any of the following conditions:" And then goes on to list possible high-risk conditions.

I.e., D-4f says (to the DAR) to restrict various things, including night and instrument flight for Aircraft with high-risk factors, until those factors are mitigated. The only issue applicable to me here appears to be with any AD's or Safety Directives that haven't been complied with while it was an SLSA.

Nothing in D4-f generally applies, nor is there any inherent restriction of night or IFR based on the manufacture's original AOI or any limitations the manufacturer had on their SLSA's. At least not that I can tell. Please let me know if you think I'm missing something.

In reading through all the possible operating limitations that could/would apply to the issuance of an E-LSA certificate, i.e. 21.191(i), nowhere do I see any restriction on IFR, or more importantly IFR into IMC (which is ultimately the bottom-line question here. If I were restricted to remaining outside of IMC, I wouldn't see the point in equipping my plane for IFR at all).

The more I look into this the more I think I'm beginning to understand. The issuance of a certificate by a DAR follows the current Order 8130.2. After the certificate is issued, the Order no longer governs anything or anyone. It's just there to instruct the DAR on how and what to do when issuing a new certificate, including what to include in the OLs. After the certificate is issued, then going forward I am bound by the applicable FAR's (aircraft, maintenance, and operator) and by my aircraft's OL's.

 

[dgaldrich]

Just because you can, doesn't mean you should. If you're not both current AND proficient, then trying to do an appoach to an unfamiliar airport to LPV minimums is an easy way into the NTSB database. Even enroute flight into clouds can be problematic if it's near the freezing level. As they used to say on the late lamented Hill Street Blues TV show -- Be careful out there.

 

[PilotMelch]

Yes. See:

Can you fly IFR in an LSA? — General Aviation News

generalaviationnews.com

Thanks Marc. I did reference that same article by Dan Johnson in my post, though the iteration I referenced was from his website, and your reference was from General Aviation News. Same content though.

Dan Johnson does conclude that you can get E-LSA, equip it, and fly IFR and IFR into IMC (if avionics are current, you're instrument rated, current, and have a medical). No specifics were given though, and with the FAA it can be about the specifics.

I began questioning it though as this seems to be the only article stating this (from all the googling I did), other than all of the people referencing Dan's article of course. He is the MAN after all. Also, the Dynon/Advanced experts on the webinar a couple of days ago specifically told an RV-12 builder he couldn't do it unless he certificated it as an E-AB. Then there were questions about requiring certified avionics, certified engine, etc., which still remain unanswered to my satisfaction.

Why did the Dynon/Advanced guys make this statement - inquiring minds want to know...

 

[PilotMelch]

Just because you can, doesn't mean you should. If you're not both current AND proficient, then trying to do an appoach to an unfamiliar airport to LPV minimums is an easy way into the NTSB database. Even enroute flight into clouds can be problematic if it's near the freezing level. As they used to say on the late lamented Hill Street Blues TV show -- Be careful out there.

Yes, always good advice. Of course, this advice applies in any aircraft, for any pilot. There's being legal, and then there is being safe.

As I stated in my original post, I really only want to be able to fly in light IFR. I'm an experienced IFR pilot and have been in some nasty stuff. I have enough experience to know I don't want to be in anything more than climbing through a light thin cloud or fog layer with this plane. But I do want to fly with the comfort and safety of being able to get on top where it may be smooth and clear. It beats the h... out of flying under a low cloud layer, bouncing around, for hours, just because you can't climb through what you know (or would like to try) as being a thin cloud layer. And it doubly beats the H... out of staying grounded out and about in a hotel for a couple of days because you can't get through that low cloud layer that you know is perfectly fine just a few thousand feet up.

And freezing precip. JUST SAY NO!!!! I've had ice on my wings. One must work to actively avoid it, IFR or VFR, IMHO.

 

[Marc_J._Zeitlin]

Thanks Marc. I did reference that same article by Dan Johnson in my post, though the iteration I referenced was from his website, and your reference was from General Aviation News. Same content though.

Sheesh. Sorry I missed that. Told you what you already know .

Dan Johnson does conclude that you can get E-LSA, equip it, and fly IFR and IFR into IMC (if avionics are current, you're instrument rated, current, and have a medical). No specifics were given though, and with the FAA it can be about the specifics.

I began questioning it though as this seems to be the only article stating this (from all the googling I did), other than all of the people referencing Dan's article of course. He is the MAN after all. Also, the Dynon/Advanced experts on the webinar a couple of days ago specifically told an RV-12 builder he couldn't do it unless he certificated it as an E-AB. Then there were questions about requiring certified avionics, certified engine, etc., which still remain unanswered to my satisfaction.

Why did the Dynon/Advanced guys make this statement - inquiring minds want to know...

So the question isn't "can you do this legally", but "where is the regulation that would preclude you from doing this?"

As Dan concludes, if you meet the requirements of your OL's (NOT some random version of 8130.2<x>, but the OL's written from them) and the requirements of 91.205 (meaning that you've equipped your aircraft with instruments and navigational equipment that meets the FAA's requirements for IFR flight) then the airplane is legal to fly IFR.

Nowhere do OL's state anything about certified engines, but 91.205 does say you WILL need "approved" navigational equipment for the route to be flown (which could be as little as "nothing" for enroute flight, if you're able to get ATC to vector you all the way to where you're going, or get approved for a pilotage or dead reckoning route) up to approved GPS navigational equipment (such as the GSP175 in my COZY MKIV). Now, the NAV equipment doesn't technically need to be TSO'd, but it needs to meet the requirements of the TSO, and really, the only way to ensure that is to buy TSO's equipment.

With respect to people saying things that are incorrect, I have never had the ability to get inside someone else's head and understand why they hold an erroneous opinion. You'd have to ask them what their basis for their incorrect reasoning is. And it MIGHT be that they were told that by someone at some FSDO, because Cthulhu knows, sometimes FSDO folks misinterpret their own rules...

My $0.02.

 

[PilotMelch]

So the question isn't "can you do this legally", but "where is the regulation that would preclude you from doing this?"

Thanks Marc. Yeah, I think this is a really good point (where is the regulation that prevents?), and seems to be about where my head has evolved to on all of this.

Nowhere do OL's state anything about certified engines, but 91.205 does say you WILL need "approved" navigational equipment for the route to be flown (which could be as little as "nothing" for enroute flight, if you're able to get ATC to vector you all the way to where you're going, or get approved for a pilotage or dead reckoning route) up to approved GPS navigational equipment (such as the GSP175 in my COZY MKIV). Now, the NAV equipment doesn't technically need to be TSO'd, but it needs to meet the requirements of the TSO, and really, the only way to ensure that is to buy TSO's equipment.

Again, another nail head hit square. The keyword here is "approved". Since most approval by the FAA comes in the form of type certification, then TSO'd equipment would certainly be approved. Of course, this equipment is approved because it meets standards for redundancy, autonomous error detection, manufacturing controls, and quality assurance processes. I.e. quality. Something to note when you're bouncing around with nothing but white outside.

But don't they also "approve" SLSA's that follow ASTM standards?

How about STC'd equipment, which is "approved" for use in specific types. There the approval is contingent on the type, so I wonder if the answer is no, or at least no based solely on that reason. I ask because Dynon's equipment is not STC'd for use in many type certificated planes.

I'm just wanting to get down to definitive answers. TSO'd equipment can be expensive, and in many cases, and in many cases doesn't play super well with the other non-TSO'd equipment; the stuff that doesn't need to be "approved".

With respect to people saying things that are incorrect, I have never had the ability to get inside someone else's head and understand why they hold an erroneous opinion. You'd have to ask them what their basis for their incorrect reasoning is. And it MIGHT be that they were told that by someone at some FSDO, because Cthulhu knows, sometimes FSDO folks misinterpret their own rules...

Agreed! Again thanks.

 

[kellym]

Thanks Marc. Yeah, I think this is a really good point (where is the regulation that prevents?), and seems to be about where my head has evolved to on all of this.



Again, another nail head hit square. The keyword here is "approved". Since most approval by the FAA comes in the form of type certification, then TSO'd equipment would certainly be approved. Of course, this equipment is approved because it meets standards for redundancy, autonomous error detection, manufacturing controls, and quality assurance processes. I.e. quality. Something to note when you're bouncing around with nothing but white outside.

But don't they also "approve" SLSA's that follow ASTM standards?

How about STC'd equipment, which is "approved" for use in specific types. There the approval is contingent on the type, so I wonder if the answer is no, or at least no based solely on that reason. I ask because Dynon's equipment is not STC'd for use in many type certificated planes.

I'm just wanting to get down to definitive answers. TSO'd equipment can be expensive, and in many cases, and in many cases doesn't play super well with the other non-TSO'd equipment; the stuff that doesn't need to be "approved".



Agreed! Again thanks.

An E-LSA airworthiness certificate once issued and the 5 hour test flight period is complete, regulation-wise is no different than an E-AB aircraft.
It isn't called experimental to just prohibit flight for hire. It is experimental. You can modify anything, as long as you recognize a "major" alteration requires a new test flight period coordinated with the local FSDO. It can have condition inspection done by any A&P. In otherwords, a paperwork distinction with no practical meeting.
I would consider adding IFR legal navigation possibly a major alteration, even though in a certified plane it might not be. Depends among other things if it is connected to an autopilot, thus affecting flight controls. I would want to fly some approaches in VFR, not under any view restriction to verify the navigator was performing as expected, all the way to 100 ft or so. Consideration should also be given to heated pitot, panel layout, whatever effect a 1/4" or less of ice might have. I agree, icing is to be avoided as much as possible.
Kelly
A&P/IA

 

[jnmeade]

If you are looking for a definitive answer, why not ask the local FSDO?

 

[airguy]

I would consider adding IFR legal navigation possibly a major alteration, even though in a certified plane it might not be. Depends among other things if it is connected to an autopilot, thus affecting flight controls.

Adding the 91.205 required equipment for IFR is not a "major alteration" - but depending on which FSDO is making the call adding an autopilot might be. "Major alteration" is one that has a significant risk of change in the operational characteristics of the airplane - how it flies, how it handles, how it performs - not how it navigates. Autopilots are connected to the flight surfaces so they have the possibility of affecting flight behavior - radios don't.

 

[jnmeade]

I'm certainly no expert and I easily get confused. I know an ELSA is not a standard certificated airplane. Still, AC43.13-1B CHG 1 is not a bad reference. Here's an excerpt.

"
11-30. GENERAL. When installing equipment
which consumes electrical power in an
aircraft, it should be determined that the total
electrical load can be safely controlled or managed
within the rated limits of the affected
components of the aircraft’s electrical power
supply system. Addition of most electrical
utilization equipment is a major alteration and
requires appropriate FAA approval. The electrical
load analysis must be prepared in general
accordance with good engineering practices.
Additionally, an addendum to the flight manual
is generally required."

Who has the FAA definition of "
Addition of most electrical
utilization equipment is a major alteration..."?

I understand the AC is talking about electrical demand and many newer avionics have lower or very low demand, but this is the FAA and logic is not necessarily controlling.

 

[airguy]

FAR 21.93 defines "minor alteration" versus "major alteration" for you.

 

[kellym]

Adding the 91.205 required equipment for IFR is not a "major alteration" - but depending on which FSDO is making the call adding an autopilot might be. "Major alteration" is one that has a significant risk of change in the operational characteristics of the airplane - how it flies, how it handles, how it performs - not how it navigates. Autopilots are connected to the flight surfaces so they have the possibility of affecting flight behavior - radios don't.

Doesn't matter whether you are connecting autopilot to the flight controls or GPS to the autopilot, it is still a major because it can affect flight control behavior. FAA opinion, not mine. A major alteration needs at least a FSDO test period and location for an experimental.
Kelly
A&P/IA

 

[kellym]

FAR 21.93 defines "minor alteration" versus "major alteration" for you.

The controlling documents are FAR 43 appendix A and AC 138 latest revision. FAA frequently defines a specific change as major even if it wouldn't be under appendix A. GPS install is one of those...not major if not connected to autopilot, major if it is.

 

[kellym]

The controlling documents are FAR 43 appendix A and AC 138 latest revision. FAA frequently defines a specific change as major even if it wouldn't be under appendix A. GPS install is one of those...not major if not connected to autopilot, major if it is.

Make that AC 20-138d.

 

[Marc_J._Zeitlin]

The controlling documents are FAR 43 appendix A and AC 138 latest revision. FAA frequently defines a specific change as major even if it wouldn't be under appendix A. GPS install is one of those...not major if not connected to autopilot, major if it is.

For TC'd aircraft, that may be the case. But 14 CFR Part 43 does not apply to E-AB aircraft, per 43.1(b)(1). And AC's (either 20-183d, or even AC43.13-1B - the bible) are not regulatory. For new OL's written for E-AB aircraft, paragraph 23 from Order 8130.2J applies, and it says:

After incorporating a major change as described in § 21.93, the aircraft owner is required to reestablish compliance with § 91.319(b) and notify the geographically responsible FSDO of the location of the proposed test area...​

​

and for most other Experimental aircraft, Paragraph 22 says:

The geographically responsible FSDO where the aircraft is based must be notified, and its response received in writing, before flying this aircraft after incorporation of a major change as defined by § 21.93. The FSDO may require demonstrated compliance with § 91.319(b). (22)​

So for Experimental aircraft, 14 CFR Part 21.93 is the controlling regulation, as @airguy stated - NOT part 43, and certainly not AC's. And 21.93 states:

A “minor change” is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product.​

The problem with this is that it's SO vague as to be almost meaningless, in the context of many modification. Change a piston engine for a turbine? Sure - obviously Major. Change an airspeed indicator with no markings for one with markings? Obviously minor. But many things in between? What's the definition of "appreciable"? WTFK?

So it's left up to the person working on the Experimental plane (either E-LSA or E-AB) to make their own determination. Does adding GPS guidance to the existing A/P "appreciably" change operational characteristics? Not in my book, but others may disagree. Does installing an A/P, with connections to the flight controls in pitch and roll, "appreciably" change the operational characteristics or reliability? Eh - MAYBE. I could go either way on that...