Experimental Avionics

weirdjim

weirdjim

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weirdjim
After 45 years in the "kit avionics" business (a-la Heathkit for airplanes) I think I know the ground rules pretty well. 21.303.b.2 says you have to have PMA for any product you produce for aircraft UNLESS the owner or the operator produces the product for their own aircraft. Several opinions of the FAA General Counsel back this up with exactly what "produce" and "own aircraft' means. I don't want to get into that catfight.

There is no mandatory TSO for com radios, VOR/LOC/GS nav radios, marker beacon radios, intercoms, audio panels, and the like for part 91 aircraft (standard and experimental). Manufacturers can CHOOSE to TSO, but that is their choice. Mostly to take care of shops that won't install anything but TSO radios (and thus boost their profit margins). So, 91.303 (b)(2) products are covered in this instance.

There ARE mandatory TSO for transponders, ELT, altitude encoders, and ADS-B. Both standard and experimental must meet the same TSO.

So, can a manufacturer who has to have mandatory TSO for their product limit the product's use to experimental versus standard certificated aircraft if they both meet the same TSO?

Somebody please bring the popcorn ...

Jim
 
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Part 21 covers manufactures.
 
What about putting the experimental version of Garnin’s G5 for a VFR only panel in a certified aircraft?


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Might be good to postpone avionics upgrades until the FAA’s MOSAIC program is released.

https://eaa.org/eaa/news-and-public...emaking-Package-Detailed-by-FAA-Administrator

The ruling will allow E/AB avionics in part 23 aircraft. A year or so from now after the ADS-B back log clears and this rule comes into effect, many new options will be available. More product will come to market. Couple this with the normal course of greater systems integration and the options will grow for us small guys. Garmin’s G3X,BK’s AeroVue EFIS, and Dynon EFIS panels require less interconnection between modules since more modules are included directly on the panel’s motherboard as compared to earlier generation systems like the older G500 or G1000.
 
AK737pilot said:
certified aircraft?
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Not to be pedantic, folks, but everything man-made in the air is certificated ("certified"). Some are certificated experimental and some are certificated normal/utility/aerobatic. And we need a generic word to take care of this trio. "normal" implies that experimentals are abnormal, which they are not. "regular" the same thing. Anybody got an idea? Factory-built? (Too long.)

Jim
 
weirdjim said:
Not to be pedantic, folks, but everything man-made in the air is certificated ("certified"). Some are certificated experimental and some are certificated normal/utility/aerobatic. And we need a generic word to take care of this trio. "normal" implies that experimentals are abnormal, which they are not. "regular" the same thing. Anybody got an idea? Factory-built? (Too long.)

Jim
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Why do we need a new term that will only confuse the issue? Certificated experimental or certificated normal/utility/aerobatic clearly describes what is being discussed. Sorry, no sympathy for some people who don't like typing long phrases.
 
I have a VAL 429 INS (integrated navigation system both VOR and ILS) in my Cherokee. I've been told that it isn't authorized. Specifically, what is my argument reference...other than this thread?
 
Timbeck2 said:
I have a VAL 429 INS (integrated navigation system both VOR and ILS) in my Cherokee. I've been told that it isn't authorized. Specifically, what is my argument reference...other than this thread?
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How about, “OK, just show me the specific regulation that prohibits it”? I think it’s up to whoever is complaining to prove it’s not allowed.
 
DaleB said:
How about, “OK, just show me the specific regulation that prohibits it”? I think it’s up to whoever is complaining to prove it’s not allowed.
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And if they come up with a regulation which in their interpretation prohibits it, how do I counter that?
 
Depends on your intestinal fortitude and obstinancy in bucking it up the chain to OK City and then to DC if it comes to that. Or, if you are fabulously wealthy, hiring a shyster to do it for you.

Jim
 
weirdjim said:
limit the product's use to experimental versus standard certificated aircraft if they both meet the same TSO?
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Are you asking... can the OEM physically/operationally "restrict" the use of their product to E/AB aircraft only even if its sold on the open market?
weirdjim said:
21.303.b.2 says you have to have PMA for any product you produce for aircraft UNLESS the owner or the operator produces the product for their own aircraft.
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Quick FYI: 21.303 has been replaced with 21.9 but covers the same issues with replacement or modification articles.
 
Timbeck2 said:
I have a VAL 429 INS ...I've been told that it isn't authorized.
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FYI: Part 21 is there if you wanted to produce (manufacture) a part for installation on a TC'd aircraft. It does not cover if you wish to install a part on a TC'd aircraft as that falls under part 43. VAL has a pretty good explanation of this on their website. For example, I've installed a number of marine band radios in aircraft which Part 21 does not apply to at all. Instead they were installed as an aircraft alteration under Part 43.
 
Bell206 said:
Are you asking... can the OEM physically/operationally "restrict" the use of their product to E/AB aircraft only even if its sold on the open market?

Yes. Let us say that a regulation requires TSO-12345 to be used in the airspace. Sparkledark Industries produces two models ... both of which are labeled with this TSO. However, Sparkledark marks one unit with model number M-123A and one unit with M-123B. Operationally and internally they are absolutely identical, but Sparkledark documentation says that M-123B is only usable in Experimental Certificated aircraft. There is no other FAA requirement on this device. Can M-123B be installeld in a standard/utility certificated factory built (i.e CessBeePipMoo) aircraft? And cite source?

Quick FYI: 21.303 has been replaced with 21.9 but covers the same issues with replacement or modification articles.

Got it. Thanks.
Click to expand...

Jim
 
weirdjim said:
a regulation requires TSO-12345 to be used in the airspace
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Do you mean by “requires” that the part must be stamped TSO or do you mean the part must meet the TSO requirements? If the part requires to be stamped TSOD then that is an operational issue and full stop, no joy. If the part only needs to meet a TSO then see below. (But as a side note, if the part must be stamped TSO to fly in national airspace then wouldn’t the E/AB aircraft also be required to have the TSO part installed???)
weirdjim said:
Can M-123B be installeld in a standard/utility certificated factory built (i.e CessBeePipMoo) aircraft?
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Yes. But not as a replacement part, rather it could be installed as an alteration under Part 43. And whether the M-123B is a major or minor alteration would be up to the installer.
weirdjim said:
cite source?
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Part 43. Once you as the installer determine the M-123B to be a Part 43 alteration the Part 21 production rules are not applicable. Part 21 is to make a part for a TC aircraft; Part 43 is to install a part on a TC aircraft. Here’s another take: VAL Avionics mentioned above has played this scenario for quite some time. Here’s their take on the process. Perhaps it may answer a question or two? If not, maybe it will generate more questions that we can try and answer.
https://www.valavionics.com/installation-in-type-certificated-aircraft.html
 
You missed the guts of the question. The two units are absolutely identical, and if one is STAMPED with the TSO, so is the other one. If all they have to do is MEET the TSO, then they both do.

The guts of the question is can the manufacturer restrict installation of model B into normal/utility/aerobatic certificated aircraft by simply changing the model number and calling it "experimental"?
 
weirdjim said:
manufacturer restrict installation of model B into normal/utility/aerobatic certificated aircraft by simply changing the model number and calling it "experimental"?
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I thought I was answering your question(s)...but NO, a manufacturer has zero influence or authority over what an aircraft owner wants or a mechanic performs. The owner has ultimate airworthiness responsibility per Part 91 and the mechanic controls his destiny per Part 43. The parts manufacturer only controls how they make parts per Part 21 and nothing more.
 
Bell206 said:
I thought I was answering your question(s)...but NO, a manufacturer has zero influence or authority over what an aircraft owner wants or a mechanic performs. The owner has ultimate airworthiness responsibility per Part 91 and the mechanic controls his destiny per Part 43. The parts manufacturer only controls how they make parts per Part 21 and nothing more.

Thank you, Bell. I don't know your a/p IA qualifications, but it seems that this isn't your first mechanic rodeo. So far as I know, if you are an IA, you and I may be the only IAs in the world that understand this subject. I've been preaching for YEARS that for minor installations the installing mechanic is the second authority and the final authority is the IA when they do either the 337 or the annual

The FAA ain't gonna go after the owner or the manufacturer. THe mech and the IA have our butts on the line for anything we sign off on.
Jim
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Bell206 said:
FYI: Part 21 is there if you wanted to produce (manufacture) a part for installation on a TC'd aircraft. It does not cover if you wish to install a part on a TC'd aircraft as that falls under part 43. VAL has a pretty good explanation of this on their website. For example, I've installed a number of marine band radios in aircraft which Part 21 does not apply to at all. Instead they were installed as an aircraft alteration under Part 43.
Click to expand...

I've seen the same, a couple in pressurized aircraft.
 
The product that comes to mind is autopilots. While the units are identical, the ones sold for EA lack the STC for production models.
 
Clip4 said:
The product that comes to mind is autopilots. While the units are identical, the ones sold for EA lack the STC for production models.
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Autopilots are really not a good example because an auto pilot is consididered a major change and therefore requires approved data vs a minor change which only needs acceptable data. That pretty much requires an stc to install it. I doubt you could ever get that through on a field approval.
 
weirdjim said:
Bell206 said: ↑
I thought I was answering your question(s)...but NO, a manufacturer has zero influence or authority over what an aircraft owner wants or a mechanic performs. The owner has ultimate airworthiness responsibility per Part 91 and the mechanic controls his destiny per Part 43. The parts manufacturer only controls how they make parts per Part 21 and nothing more.

Thank you, Bell. I don't know your a/p IA qualifications, but it seems that this isn't your first mechanic rodeo. So far as I know, if you are an IA, you and I may be the only IAs in the world that understand this subject. I've been preaching for YEARS that for minor installations the installing mechanic is the second authority and the final authority is the IA when they do either the 337 or the annual

The FAA ain't gonna go after the owner or the manufacturer. THe mech and the IA have our butts on the line for anything we sign off on.
Jim
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As an owner who considers his A&P/IA a good friend, I wouldn't like to be responsible for putting his butt on the line for asking him to sign off on something that wasn't completely, inarguable kosher. In the instance you described specifically above, namely...

"...Let us say that a regulation requires TSO-12345 to be used in the airspace. Sparkledark Industries produces two models ... both of which are labeled with this TSO. However, Sparkledark marks one unit with model number M-123A and one unit with M-123B. Operationally and internally they are absolutely identical, but Sparkledark documentation says that M-123B is only usable in Experimental Certificated aircraft. There is no other FAA requirement on this device. Can M-123B be installeld in a standard/utility certificated factory built (i.e CessBeePipMoo) aircraft? And cite source?"

... WOULD that be putting an A&P/IA in a potentially difficult situation? I'm hoping not...
 
Didn't B&C get in trouble years ago for selling backup alternators clearly marked for the experimental market but were being used in normal certified aircraft? From what I read at the time it seemed the FAA really picked on them.
 
skipnsb said:
Didn't B&C get in trouble years ago for selling backup alternators clearly marked for the experimental market but were being used in normal certified aircraft? From what I read at the time it seemed the FAA really picked on them.
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If you're talking about the Super Cub installs in Alaska back in the mid-90s the you're correct the FAA "picked" on B&C. But it was more a witch-hunt than anything. Funny thing was each B&C install had an FAA signed field approval which the Oak City suits failed to acknowledge. In the end, B&C had done nothing wrong which was backed up by another FAA employee named Bill O'Brien. However, that end result, in my opinion, is still muddied by the bs given to B&C by the feds. Things changed after that.
 
In the real world, the Exp category panels are really superior to those available for the certified world. I hope the day comes soon when I have the option to put one of those in my plane. Especially using one of the pre fabricated wiring looms and a "junction" box.
 
Bell206 said:
Quick FYI: 21.303 has been replaced with 21.9 but covers the same issues with replacement or modification articles.
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Mr. Bell is in fact correct. 21.303 (b) (2) has been translated verbatim to 21.9 (a) (5). Same exact provision for owner-produced parts. Anybody got a good copy of the FAA Legal Counsel's long letter on this matter saying what can and cannot be done during the manufacture of the part(s)?
 
The argument about legal ability to put experiential avionics in a certified part 23 plane reminds me of people arguing why the income tax is illegal. Many would rather pay the extra and be well inside of the regs rather than hugging the ragged edge and arguing to get out of trouble. But that’s just me.
 
NordicDave said:
The argument about legal ability to put experiential avionics in a certified part 23 plane reminds me of people arguing why the income tax is illegal. Many would rather pay the extra and be well inside of the regs rather than hugging the ragged edge and arguing to get out of trouble. But that’s just me.
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If the chief IRS legal counsel wrote a multi-page letter citing chapter and verse of why it is illegal, are you saying that you'd disregard the opinion of the IRS' own chief lawyer?

Jim
 
NordicDave said:
The argument about legal ability to put experiential avionics in a certified part 23 plane... Many would rather pay the extra and be well inside of the regs rather than hugging the ragged edge and arguing to get out of trouble. But that’s just me.
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FWIW: technically there is no such thing as "experimental" avionics or parts. That is solely a marketing tag vendors put on parts they sell so not to run afoul with Part 3 or other SUP guidance. The PMA/TSO references are needed to sell those parts not necessarily to install them. So any part is technically available to be installed in a TCd aircraft. As to "hugging the ragged edge" I guess it depends on your definition. I've installed and signed off quite a few non-PMA and non-TSO items (marine/CB radios, car radios, storage devices, etc) that have zero "approvals" on TC aircraft and was never near any "ragged edge" regulatory wise. So it really is more a decision to pay extra for personal reasons rather than regulatory reasons.
 
I remember Bill O'Brien's writings on owner produced parts, I don't have a copy but it sure seemed liberal. After all, since no one can actually see the type certificate, how can anybody ever say that a part (or an airplane for that matter) conforms to the type certificate? Metal testing of the factory part?

I am appreciate of Weirdjim's down to earth writings on this matter. As former IRS and tax lawyer, at least the tax code was somewhat consistent, or if not always consistent, there were logical reasons for the disputes between different courts. Don't most Advisory Circulars say "this is one way, but not the only way".

Other than the ADSB out, transponder, altitude encoder, and autopilot, why can't any
"box" be installed as a minor mod. Years ago the big dog avionics shop filed a complaint with the FAA about a local independent ap installing a KX170B, not sure how that turned out. We all know the 170b's were not tso, but it was legal to fly ifr with them. But it had the effect on my rural airport that nobody wanted to risk the FAA ire by installing radios.

I would appreciate specific references to any certification or pma or tso advisory or rule of AC or law or whatever that makes it illegal for my ap to install "experimental" boxes in my regular not for hire Cessna 172. Or, if it might be legal to install, but there is some prohibition against use for ifr unless a box has a special sticker.

I am not trying to start an argument, just trying (again) to understand. I am finally getting the old bird out of mothballs, would want to put in some "experimental" avionics.
 
skipnsb said:
I don't have a copy b
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https://www.aviationpros.com/home/article/10388083/i-vs-we
skipnsb said:
legal to install
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Start here for a foundation, then address each install individually. Hopefully your AP is also your IA but if not important to include them as well. However, if install is good and documented properly should not be an issue.
https://www.valavionics.com/installation-in-type-certificated-aircraft.html
skipnsb said:
use for ifr
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Equipment requirements for IFR are in 91.205. And a transponder only needs to meet the requirements of the TSO not be TSOd.
 
Bell206 said:
I've installed and signed off quite a few non-PMA and non-TSO items (marine/CB radios, car radios, storage devices, etc) that have zero "approvals" on TC aircraft and was never near any "ragged edge" regulatory wise. So it really is more a decision to pay extra for personal reasons rather than regulatory reasons.
Click to expand...

Thanks Bell for the reply, got me thinking. I'm having a harder time with avionics with software that requires FAA Approval. The feature set in experimental seems more rich than the certified sibling.

On a side note installing a CB sounds pretty darn cool. Especially talking to truckers when following roads.
 
weirdjim said:
So, can a manufacturer who has to have mandatory TSO for their product limit the product's use to experimental versus standard certificated aircraft if they both meet the same TSO?

Somebody please bring the popcorn ...

Jim
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Go to just about any avionics makers website. You will see two of same box, same part number, one sold for experimental only, one sold for TC aircraft. The experimental on is usually way less expensive. Hmmm, Uavionix skybeacon comes to mind, as an example. Both must meet same TSO requirements, one is cheaper than the other.
 
NordicDave said:
On a side note installing a CB sounds pretty darn cool. Especially talking to truckers when following roads.
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You have NO IDEA what getting a ham radio license and putting a 2 meter transceiver in your aircraft will do. In most of the midwest, at altitude they will bring up repeaters from four states around. GREAT for cross country AND for getting local information and/or meeting fellow hams as you land for fuel or overnight. Sometimes an invite to stay in the spare bedroom as you go across. Pilots and hams have the same sort of bond ... I'd do ANYTHING for a fellow pilot OR ham that landed and wanted overnight lodging ... even if it meant a pup tent in the back yard with a sleeping bag if I didn't have room in the house ... and generally a home-cooked meal in the deal.

Met a lot of great friends that way. Of course, there is the off jerk, but that is rare in these two communities.

But the Missouri family that cooked my wife and I a rack of smoked ribs twenty or thirty years ago went WAY above when we shut it down in the Ozarks in a horrendous thunderstorm will be with me forever.

Jim
 
There seems to be a good deal of overlap between the ham and pilot communities. The overall demographics are about the same... overwhelmingly male, old and white. :: shrug ::
 
DaleB said:
There seems to be a good deal of overlap between the ham and pilot communities. The overall demographics are about the same... overwhelmingly male, old and white. :: shrug ::
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You see male, old, and white... I just see self-driven, intelligent do-ers who don't take the easy way out. Race, age, and gender have nothing to do with it. On the other hand, I can't explain why the demographic ended up the way you described it, because it does seem accurate now that you mention it. I don't know any pilots or ham operators who would be anything other than welcoming to someone who wasn't old, white, or male.
 
DaleB said:
There seems to be a good deal of overlap between the ham and pilot communities. The overall demographics are about the same... overwhelmingly male, old and white. :: shrug ::
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There also seems to be a strong overlap with pilots, motorcyclists, and sailors as well. It seems that we love somewhat technical risky hobbies.
 
MuseChaser said:
You see male, old, and white... I just see self-driven, intelligent do-ers who don't take the easy way out. Race, age, and gender have nothing to do with it. On the other hand, I can't explain why the demographic ended up the way you described it, because it does seem accurate now that you mention it. I don't know any pilots or ham operators who would be anything other than welcoming to someone who wasn't old, white, or male.
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Doug Reid said:
Yeah...I am male, old and white...Amateur Extra who loves CW, A&P/IA...former fireman, paramedic, rock guitarist, recording engineer. During my lifetime if I wanted something I worked hard to get it...no apologies. I go out of my way to help anyone who needs assistance unless they are a smart a$$ and disrespect others.
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Yes to all. I have noticed that most of my interests over the years (flying, ham radio, motorcycling, target shooting) have all fallen into the same demo. I noticed it even when I was typically the youngest guy in each crowd -- flying being the biggest exception; lots of 20-something students and CFIs around here. And I don't know of a single group that would not / does not welcome anyone regardless of whether they are "old, male, and white". I can't explain why there isn't more diversity in those crowds...

I don't know if it's just the proximity to UNO and their aviation program, but we do see a lot of younger and female pilots around here.
 
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