Avionics TSO v. non TSO

Arnold

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Arnold
Where is the regulatory requirement that says an owner cannot put avionics that do not have TSO compliance in their aircraft? I am aware that such a regulation exists for part 135 and 121, just not for part 91 operations.

If one looks at several of the avionics manufacturers they designate their boxes as either experimental or certified. This experimental and certified refers to the aircraft category and not the avionics.

In many cases the avionics appear to be identical except for the TSO certification.

So my question is: What is the regulatory requirement that prevents the installation of so called "experimental" avionics in a certified aircraft. Is it in a maintenance reg? Is it in an operating reg? Is it in a certification reg? Is it in the TCDS? To my knowledge the answer is non of the above. Please include the citation(s) in your answer.
 
kind of a counter point: technically, you can have equipment installed that doesn't have an actual TSO "certification". The FARs tend to say something like "an approved terrain awareness and warning system that meets the requirements for Class A equipment in Technical Standard Order (TSO)-C151". Notice that it doesn't say that the system has to actually have a TSO cert.

I would be doubtful that there is any regulation preventing the installation of so called "experimental" avionics. As long as the airplane is otherwise properly equipped and the so called "experimental" avionics doesn't create a hazard, there wouldn't be a basis to complain. Kind of like installing an entertainment system in the airplane.
 
TSO, in general, is neither necessary nor sufficient justification to install something in an aircraft. There are a few places that mandate certain TSO compliance (ELTs, for example).
 
Where is the regulatory requirement that says an owner cannot put avionics that do not have TSO compliance in their aircraft?
There isn’t one.
If one looks at several of the avionics manufacturers they designate their boxes as either experimental or certified. This experimental and certified refers to the aircraft category and not the avionics.
There is no such thing as an “experimental” part. Vendors also have no authority to dictate what type of aircraft their part can be installed. That is up to the installer.

The reason vendors started to label their parts “experimental” was due to a new FAR Part 3 that prohibited “fraudulent and intentionally false statements” about parts that may be installed on a TC’d aircraft. Putting “experimental” in the name in their sales info is one way vendors don’t violate Part 3. But it has zero to do with Part 43 installs. FYI: Part 3 also contains the only regulatory definition of airworthy as well.
https://www.ecfr.gov/cgi-bin/text-i...256246b2bd10b4&mc=true&node=pt14.1.3&rgn=div5

Other vendors use different methods like Wag-Aero’s part production codes.
https://www.wagaero.com/code-system
In many cases the avionics appear to be identical except for the TSO certification.
In most cases they are and they are produced on the same line with the only difference being the data tag glued on.
So my question is: What is the regulatory requirement that prevents the installation of so called "experimental" avionics in a certified aircraft.
Nothing prevents the installation. However, the part must be installed per the correct Part 43 process. A part can either be installed as a replacement, or as an alteration. For a part to qualify as a replacement part it must be FAA approved via a STC, owner-produced, PMA, etc. AC 20-62 goes into more detail.
https://www.faa.gov/regulations_pol...cfm/go/document.information/documentID/780198

Keep in mind a replacement part is along the lines of remove Part A and install a new Part A, or in the case of 3rd party PMA parts it would be Part A1. With all these parts approved no further approvals are needed as the replacement part conforms to the aircraft type design. ***Well except TSO parts as they do not provide an installation approval but that is for a different discussion.

For all other part installs it will fall under the alteration process as either a minor or major alteration which alters or changes the aircraft type design and requires additional approvals.

So in order to install your part, whether it be an “experimental” GARMIN, a floor mat from NAPA, a marine radio, or a Kohler deluxe commode in your aircraft, it requires a separate approval for that specific type design alteration. And the type of approval data needed will depend on whether the installer determines it is a minor alteration which requires acceptable data, or if it is a major alteration which requires FAA approved data.

VAL Avionics has a good article detailing the installation of non-TSO avionics in TC’d aircraft using the same alteration process.
https://www.valavionics.com/installation-in-type-certificated-aircraft.html
 
There isn’t one.

There is no such thing as an “experimental” part. Vendors also have no authority to dictate what type of aircraft their part can be installed. That is up to the installer.

The reason vendors started to label their parts “experimental” was due to a new FAR Part 3 that prohibited “fraudulent and intentionally false statements” about parts that may be installed on a TC’d aircraft. Putting “experimental” in the name in their sales info is one way vendors don’t violate Part 3. But it has zero to do with Part 43 installs. FYI: Part 3 also contains the only regulatory definition of airworthy as well.
https://www.ecfr.gov/cgi-bin/text-i...256246b2bd10b4&mc=true&node=pt14.1.3&rgn=div5

Other vendors use different methods like Wag-Aero’s part production codes.
https://www.wagaero.com/code-system

In most cases they are and they are produced on the same line with the only difference being the data tag glued on.

Nothing prevents the installation. However, the part must be installed per the correct Part 43 process. A part can either be installed as a replacement, or as an alteration. For a part to qualify as a replacement part it must be FAA approved via a STC, owner-produced, PMA, etc. AC 20-62 goes into more detail.
https://www.faa.gov/regulations_pol...cfm/go/document.information/documentID/780198

Keep in mind a replacement part is along the lines of remove Part A and install a new Part A, or in the case of 3rd party PMA parts it would be Part A1. With all these parts approved no further approvals are needed as the replacement part conforms to the aircraft type design. ***Well except TSO parts as they do not provide an installation approval but that is for a different discussion.

For all other part installs it will fall under the alteration process as either a minor or major alteration which alters or changes the aircraft type design and requires additional approvals.

So in order to install your part, whether it be an “experimental” GARMIN, a floor mat from NAPA, a marine radio, or a Kohler deluxe commode in your aircraft, it requires a separate approval for that specific type design alteration. And the type of approval data needed will depend on whether the installer determines it is a minor alteration which requires acceptable data, or if it is a major alteration which requires FAA approved data.

VAL Avionics has a good article detailing the installation of non-TSO avionics in TC’d aircraft using the same alteration process.
https://www.valavionics.com/installation-in-type-certificated-aircraft.html

hey bell, do you keep this in a cut an paste file? it seems that we go through this every couple of months.
 
14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

Section 91.205 —Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements.

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:

(2) Two-way radio communication and navigation equipment suitable for the route to be flown.

For IFR, the equipment has the TSO or have a statement from the manufacture stating is meets the requirement of the TSO.
 
You can put in whatever you want. The chance the FAA will find out is minimal, unless something happens. But better be able to face any consequences that come down when the FAA does find out.
 
14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

Section 91.205 —Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements.

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:

(2) Two-way radio communication and navigation equipment suitable for the route to be flown.

For IFR, the equipment has the TSO or have a statement from the manufacture stating is meets the requirement of the TSO.

The regs don't say that and fortunately, the FAA doesn't have that requirement in general. The FAA doesn't give a hoot for most of us if your com radio or VORs are TSO. IFR GPSs are an exception to that.
 
14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

Section 91.205 —Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements.

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:

(2) Two-way radio communication and navigation equipment suitable for the route to be flown.

For IFR, the equipment has the TSO or have a statement from the manufacture stating is meets the requirement of the TSO.
Please quote chapter and verse were you came up with that, I’ll wait......
 
Please quote chapter and verse to support your claim. You were the one who made it. Regs do not require TSO in general for non-commercial operators. There are a few specific places it is required but "because you're flying IFR" is not one of them.
 
Keep in mind what a TSO certificate means. The TSO is a performance requirement. So yes, for certain specific equipment like an ELT or IFR “certified” GPS, TSO certified is required. Non-TSO certified equipment can be installed depending the specific equipment. A VOR or radio are examples, but a PFD display is an example of another piece of equipment that must have a TSO certificate, because it must meet certain performance requirements.
 
what a TSO certificate
FYI: there is no certificate. Its actually a TSOA with the A for approval. And while it is technically a mininum performance standard in the context of this discussion the TSOA is the design and production approval that allows the vendor to create and sell the part but not install it.
 
The key is any required equipment needs to be produced in accordance with 14 CFR part 21.9 in TC’ed aircraft...

From FAA order 8300.16:

10. Commercial Off-the-Shelf (COTS) and Other Articles Not Produced Under § 21.9.

a. COTS Articles. COTS refers to articles that have been developed for sale to the general public. For the purposes of this order, both COTS and articles not produced under § 21.9 are addressed in the same manner. Installation of such articles can be approved but requires an evaluation based on their intended functions and failure modes and effects. In addition, such articles installed for “situational awareness” or as a supplemental system may be acceptable provided they do not interfere with or displace required equipment, or otherwise interfere with the safe operation and airworthiness of the aircraft.

b. Installation of COTS Articles. Section 21.9 was not intended to restrict an owner or operator or their repair and maintenance facility or person from installing “commercially available” articles on their products.
 
TSO is just one way to make an approved article. So you don't even have to go to the COTS level.
 
The sad part about the entire TSO/Non TSO equipment is the fact that it’s all about a paper trail. In most cases there is NO DIFFERENCE in the actual product (Fact) just the designation and paperwork behind it. Take for example and told to me by several “Reps” the G5’s, as are the G3X all the same…well except for their price. The G3X going into an experimental aircraft, as opposed to a certified one is thousands less to purchase. Crazy IMO.
 
The sad part about the entire TSO/Non TSO equipment is the fact that it’s all about a paper trail. In most cases there is NO DIFFERENCE in the actual product (Fact) just the designation and paperwork behind it. Take for example and told to me by several “Reps” the G5’s, as are the G3X all the same…well except for their price. The G3X going into an experimental aircraft, as opposed to a certified one is thousands less to purchase. Crazy IMO.
It’s not so much a paper trail as it is two separate sets of rules and oversight between Part 21 and Part 43. This is the reason a Part 43 installer can install a "non-certified" G3X in a TC’d aircraft but the Part 21 manufacturer is required to develop a separate approval/label for both models. The funny thing is Garmin could simply drop the "experimental" G3X/G5 and only sell "certified" marked equipment considering they are the same thing. Yet for some reason they don’t. I have yet to have an OEM rep answer that question honestly.
 
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As I (mis?)understand it, TSO/non-TSO is irrelevant for any type of avionics that weren't originally available for the aircraft, so a kind of device that wasn't at least an option for your panel in (say) 1963 when your plane was made is going to need an STC anyway.
 
That's an incorrect statement as well. Again, TSO is neither a necessary or sufficient condition to install things in airplanes, in general. In general means for all cases.
For most of us non-commercial guys, TSO isn't strictly necessary except for a few things were it is called out (ELTs, IFR GPS, etc...). Even in these cases, it may not be ALL that is required. For instance, your IFR GPS will also need an STC. Other things, like a comm radio don't need TSO and if the installation doesn't rise to the level of being a major modification, you don't need much other approval than it coming from an approved source and signed off by an appropriate mechanic.

While TSOA doubles as approval for manufacture, it's not the only way to get it. TCs and STCs have their own approval inherent. PMA is also approval. So is meeting certain approved standards (like mil-spec for fasteners, fluids, etc...).
 
14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

Section 91.205 —Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements.

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:

(2) Two-way radio communication and navigation equipment suitable for the route to be flown.

For IFR, the equipment has the TSO or have a statement from the manufacture stating is meets the requirement of the TSO.

Your post is disingenuous as it makes it look like your last sentence is a quotation from 91.205, but it is not a quotation of anything, but rather merely your opinion.
 
There isn’t one.

There is no such thing as an “experimental” part. Vendors also have no authority to dictate what type of aircraft their part can be installed. That is up to the installer.

The reason vendors started to label their parts “experimental” was due to a new FAR Part 3 that prohibited “fraudulent and intentionally false statements” about parts that may be installed on a TC’d aircraft. Putting “experimental” in the name in their sales info is one way vendors don’t violate Part 3. But it has zero to do with Part 43 installs. FYI: Part 3 also contains the only regulatory definition of airworthy as well.
https://www.ecfr.gov/cgi-bin/text-i...256246b2bd10b4&mc=true&node=pt14.1.3&rgn=div5

Other vendors use different methods like Wag-Aero’s part production codes.
https://www.wagaero.com/code-system

In most cases they are and they are produced on the same line with the only difference being the data tag glued on.

Nothing prevents the installation. However, the part must be installed per the correct Part 43 process. A part can either be installed as a replacement, or as an alteration. For a part to qualify as a replacement part it must be FAA approved via a STC, owner-produced, PMA, etc. AC 20-62 goes into more detail.
https://www.faa.gov/regulations_pol...cfm/go/document.information/documentID/780198

Keep in mind a replacement part is along the lines of remove Part A and install a new Part A, or in the case of 3rd party PMA parts it would be Part A1. With all these parts approved no further approvals are needed as the replacement part conforms to the aircraft type design. ***Well except TSO parts as they do not provide an installation approval but that is for a different discussion.

For all other part installs it will fall under the alteration process as either a minor or major alteration which alters or changes the aircraft type design and requires additional approvals.

So in order to install your part, whether it be an “experimental” GARMIN, a floor mat from NAPA, a marine radio, or a Kohler deluxe commode in your aircraft, it requires a separate approval for that specific type design alteration. And the type of approval data needed will depend on whether the installer determines it is a minor alteration which requires acceptable data, or if it is a major alteration which requires FAA approved data.

VAL Avionics has a good article detailing the installation of non-TSO avionics in TC’d aircraft using the same alteration process.
https://www.valavionics.com/installation-in-type-certificated-aircraft.html

This is by far the most clear and comprehensive explanation I have seen. Ought to be a sticky. Thanks for writing.

A few questions:

If a TSO part has an STC with AML, does that mean that installing it in listed aircraft is not an alteration?

If a TSO part does not have an STC or PMA, does that mean that installing it is always an alteration?
 
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lets look at that, first it is a paper put out by a manufacture, not the feds. given that, its pretty well written. so lets look at what it says.


14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

Section 91.205 —Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements.

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:

(2) Two-way radio communication and navigation equipment suitable for the route to be flown.

There are also some general references as to the performance requirements of installed equipment. Please refer to 14 CFR 23 Subpart F Section 23.2505, 23.2510, 23.2520

§ 23.2505 Function and installation.
When installed, each item of equipment must function as intended.

§ 23.2510 Equipment, systems, and installations.
For any airplane system or equipment whose failure or abnormal operation has not been
specifically addressed by another requirement in this part, the applicant must design and install
each system and equipment, such that there is a logical and acceptable inverse relationship
between the average probability and the severity of failure conditions to the extent that: (a) Each catastrophic failure condition is extremely improbable; (b) Each hazardous failure condition is extremely remote; and (c) Each major failure condition is remote.


§ 23.2520 High-intensity Radiated Fields (HIRF) protection.
(a) Each electrical and electronic systems that perform a function, the failure of which
would prevent the continued safe flight and landing of the airplane, must be designed and
installed such that—
(1) The function at the airplane level is not adversely affected during and after the time
the airplane is exposed to the HIRF environment; and (2) The system recovers normal operation of that function in a timely manner after the
airplane is exposed to the HIRF environment, unless the system’s recovery conflicts with other
operational or functional requirements of the system. (b) For airplanes approved for IFR operations, each electrical and electronic system that
performs a function, the failure of which would significantly reduce the capability of the airplane
or the ability of the flightcrew to respond to an adverse operating condition, must be designed
and installed such that the system recovers normal operation of that function in a timely manner
after the airplane is exposed to the HIRF environment.

nowhere in that does it even mention "meets a TSO"

23.2505 is pretty easy to read.
23.2510 pretty straight forward also, if it fails it will not affect other systems.
23.2520 if it says meets FCC regulations its pretty much covered.
next:

At this point it would be the responsibility of the installer to verify that the installed equipment meets the requirements of the above part 23 sections:

that is the important part right there. there is no requirement that a piece of equipment either have, or meet a tso in the regs, period.
 
Keep in mind what a TSO certificate means. The TSO is a performance requirement. So yes, for certain specific equipment like an ELT or IFR “certified” GPS, TSO certified is required. Non-TSO certified equipment can be installed depending the specific equipment. A VOR or radio are examples, but a PFD display is an example of another piece of equipment that must have a TSO certificate, because it must meet certain performance requirements.

somebody better tell dynon and garmin that, as both the G3X and HDX are not TSO'd
 
As I (mis?)understand it, TSO/non-TSO is irrelevant for any type of avionics that weren't originally available for the aircraft, so a kind of device that wasn't at least an option for your panel in (say) 1963 when your plane was made is going to need an STC anyway.
Not quite. For the most part you’re intermixing requirements: certification and operational. But without specific examples there are too many variables to reply with one answer to your TSO comment. Same with whether an item requires an STC vs was an OEM option in order to install. Too many variables to answer simply. However, that said, in most cases if an OEM offered an option that was part of the 1963 aircraft specifications then no further approvals would be needed to install that specific OEM option.
 
If a TSO part has an STC with AML, does that mean that installing it in listed aircraft is not an alteration? If a TSO part does not have an STC or PMA, does that mean that installing it is always an alteration?
First, the type of Part 21 part certification (STC, PMA, TSO) does not determine the installation method per Part 43. So whether the part installation is an alteration or not is determined separately from the part certification by the installer. Second, you are “mismatching” the part certifications. How a TSO part “interacts” with STCs and PMAs is a separate topic and specific to the part at hand. There is also the issue of the part design and production approvals that usually dictate which certification "controls" the installation. For example, take a Concorde battery where some models have an STC, PMA, and TSO approval associated for the same battery model. So which one will you use?
 
Your post is disingenuous as it makes it look like your last sentence is a quotation from 91.205, but it is not a quotation of anything, but rather merely your opinion.
That was not my intention.
 
In those cases the certification was provided through the STC process, with an FAA AML list. I bet if you look at what was required for STC approval, it is much more in depth than only a TSO set of requirements.

http://static.garmin.com/pumac/sa01899wi_aml_2.pdf
But that’s not what you put in your post you stated that a mfd requires a tso, it does not. I also believe you can install a full Dynon system in an aircraft with at most a 337, provided you keep all primary required equipment. The Dynon and Garmin require a stc because it replaces primary equipment required by the original tcds.
 
But that’s not what you put in your post you stated that a mfd requires a tso, it does not. I also believe you can install a full Dynon system in an aircraft with at most a 337, provided you keep all primary required equipment. The Dynon and Garmin require a stc because it replaces primary equipment required by the original tcds.

Agree. I went and looked over the info on the Garmin website. I suspect if you look at the actual STC, which I haven’t, they probably also show compliance to various TSOs.
 
So my question is: What is the regulatory requirement that prevents the installation of so called "experimental" avionics in a certified aircraft. Is it in a maintenance reg? Is it in an operating reg? Is it in a certification reg? Is it in the TCDS? To my knowledge the answer is non of the above. Please include the citation(s) in your answer.
See highlighted above.

Here is an example: All transponders are required to meet a TSO. It's in the operating regs -
14 CFR § 91.215 - ATC transponder and altitude reporting equipment and use.

Anytime operating regs say a TSO is required, it's required unless specifically exempted.
 
I suspect if you look at the actual STC, which I haven’t, they probably also show compliance to various TSOs.
FYI: given an STC is a design approval most vendors use just the production approvals from a TSO or a PMA to manufacture the parts/equipment vs the design side. I believe you'll find on most of Garmins more complex STCs they actually use the FARs as their certification basis vs a TSO since there are only a limited amount of TSOs.
 
TSO is required,
FWIW: its mainly a semantics issue but most regulations only state the equipment must meet the requirements of a TSO... which is not the same as the equipment is approved under a TSO and marked accordingly per 45.15.
 
FWIW: its mainly a semantics issue but most regulations only state the equipment must meet the requirements of a TSO... which is not the same as the equipment is approved under a TSO and marked accordingly per 45.15.
the most common method of identifying a product meets the environmental and performance requirements of a TSO is with a tag and/or markings.
 
See highlighted above.

Here is an example: All transponders are required to meet a TSO. It's in the operating regs -
14 CFR § 91.215 - ATC transponder and altitude reporting equipment and use.

Anytime operating regs say a TSO is required, it's required unless specifically exempted.

I did forget to mention that there are a small number of regulatory requirements pertaining to meeting TSO requirements.
 
Ok, so same question. Went out for acro practice in my Decathlon today. Afterwards, when I set cruise power to return to my home airfield, I saw this. My airplane may be rated for 6G, but my manifold pressure gauge apparently cannot stand up to 4G.

man pressure (2).jpg

So I go to Aircraft Spruce to price a replacement. Holy %)*#@%! Over a thousand bucks for the TSO gauge. Or $300 for a non-TSO.

What say you all?
 
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