Non-TSO for Certified Aircraft

[Bell206]

merely asking.

VAL has had this document out for a few years.
https://www.valavionics.com/installation-in-type-certificated-aircraft.html

 

[Timbeck2]

Yep, read it. All about meeting TSO requirements not PMA which is what the FAA is all concerned about. You being an IA and all...what's your take?

 

[Bell206]

.what's your take?

Not an IA. But it is a non-issue for me. First, the FAA is only pointing out the VAL equipment does not meet Part 21.9(a). Nothing more. It doesn't state those parts are illegal which if they were, there would have been an AD issued to remove them.

Also a TSO is only a production approval whereas a PMA is a production and installation approval. Apples and oranges.

Any part installation falls to the installer, i.e., A&P, which VAL states is the final authority. If VAL was BS'n their product was "approved" for install in a TC'd aircraft then they would be in violation of Part 3 and shutdown...which they are not.

And as I mentioned above, the UPN is strictly a production issue not an installation issue. Just as the owner produced part thread described. Bottomline, you can install anything you want into a TC'd aircraft like the marine radio above, or a Cobra CB, or the infamous chinese LED landing light, or a Kohler commode. However, I think think the latter would be a major alteration.

 

[Timbeck2]

My apologies, I thought you were an IA. Appreciate you taking the time.

 

[tinerj]

It depends on what your definition of 'installed' is. I can 'install' things by attaching them to the instrument panel with velcro. But it isn't installed according to the FAA.

 

[Checkout_my_Six]

stupid.....but true.

 

[Tom-D]

Yep, read it. All about meeting TSO requirements not PMA which is what the FAA is all concerned about. You being an IA and all...what's your take?

PMA is authorization to produce a part to replace a OEM's part.
TSO is a specification requirement. the part must meet certain specifications to be used in certain applications.

example: King's KX170 / KX170B. one can be used in part 135 ops one can't.

https://www.valavionics.com read their claims. I've had three of their radios all worked great.

 

[Tom-D]

Yep, read it. All about meeting TSO requirements not PMA which is what the FAA is all concerned about.

Where is this written?

Appliances do not need PMA, they were not manufactured by the OEM. you have choices of the equipment you use.

 

[flyingron]

Yep, read it. All about meeting TSO requirements not PMA which is what the FAA is all concerned about.

PMA is not a strict requirement. In fact, if manufactured under a TSOA or Type Certificate or Supplemental Type Certificate, the manufacturing authority is not PMA.

And just because the part was manufactured under some legal authority doesn't make it legal to install.

There are pretty much three things you need:

1. A part validly manufactured (PMA, one of the other approvals, legitimate owner produced part, or meeting some approved standard like Mil-spec).
2. Authority to install it on this PARTICULAR aircraft (a TSO is rarely sufficient in itself, and frequently not even required). As stated early in this thread, it needs to be on the type certificate, STC, an appropriate PMA, or is a minor change).
3. Someone to properly install it and fill out the appropriate paperwork.

 

[unsafervguy]

PMA is not a strict requirement. In fact, if manufactured under a TSOA or Type Certificate or Supplemental Type Certificate, the manufacturing authority is not PMA.

And just because the part was manufactured under some legal authority doesn't make it legal to install.

There are pretty much three things you need:

1. A part validly manufactured (PMA, one of the other approvals, legitimate owner produced part, or meeting some approved standard like Mil-spec).
2. Authority to install it on this PARTICULAR aircraft (a TSO is rarely sufficient in itself, and frequently not even required). As stated early in this thread, it needs to be on the type certificate, STC, an appropriate PMA, or is a minor change).
3. Someone to properly install it and fill out the appropriate paperwork.

That’s where a radio mostly falls, putting a radio in a panel that requires nothing more than installing a few screws in the side of the tray to install it is a minor alteration and is up to the a&p

 

[chris elliott]

You are absolutely and totally incorrect.

Jim

Jim,

Sorry to jumpstart an old thread, but I recently bought a very well maintained Cessna 150, however the avionics and now being required to have ADS-B out due to being 3 miles within a mode c veil, can easily triple the value of the airframe. If I’m correct what your saying is that as long as it meets the TSO’d standards then non-tso’d May be installed?

 

[Tom-D]

Jim,

Sorry to jumpstart an old thread, but I recently bought a very well maintained Cessna 150, however the avionics and now being required to have ADS-B out due to being 3 miles within a mode c veil, can easily triple the value of the airframe. If I’m correct what your saying is that as long as it meets the TSO’d standards then non-tso’d May be installed?

I believe the ADSB transponder must be TSO'ed.
not your AV expert.

 

[chris elliott]

Mainly the radio and transponder, both which are dated. The ADS-B out is another main concern. I know that this is the "joy" of aircraft ownership, but as we all know there are a lot of experts (i mean this in the most respectful way) out there who all seem to disagree due to the FAA's seemingly vague statutes. I really love the 150, but the eventual costs could just make this a bad business move. I guess my biggest beef is to see a lot of 150's destined to the ramp because of the elevated costs of mis-interpretations.

 

[bradg33]

Transponder must be TSO'd per 91.215 ("For operations not conducted under part 121 or 135 of this chapter, ATC transponder equipment installed must meet the performance and environmental requirements of any class of TSO-C74b (Mode A) or any class of TSO-C74c (Mode A with altitude reporting capability) as appropriate, or the appropriate class of TSO-C112 (Mode S)"). There is no requirement in the regulations (for part 91 at least) that requires a TSO'd comm radio.

 

[weirdjim]

Jim,

Sorry to jumpstart an old thread, but I recently bought a very well maintained Cessna 150, however the avionics and now being required to have ADS-B out due to being 3 miles within a mode c veil, can easily triple the value of the airframe. If I’m correct what your saying is that as long as it meets the TSO’d standards then non-tso’d May be installed?

Three things have to MEET the standards, and I would argue that the manufacturer has to verify that they MEET the standards or you have to have one hell of a well-appointed test lab in your garage. (Transponder, ELT, and now ADSB.). EVERYTHING ELSE in avionics does NOT have to have or meet any TSO.

Jim

 

[waylon scudder]

This information is coming straight from the FAA so don't bother to argue with it.
I have a lot more Info on this topic if anyone would like to see it.
NON TSO'd EQUIPMENT CAN BE INSTALLED IN A CERTIFIED AIRCRAFT ALL DAY LONG. LEGALLY!

DEPARTMENT OF TRANSPORTATION
FEDERAL AVIATION ADMINISTRATION
ADVISORY CIRCULAR
AC:20-41A
DATE:4/5/1977
SUBJECT: SUB.5TITUTE TECHNICAL STANDARD ORDER (TSO) AIRCRAFT EQUIPMENT
1. PURPOSE. This circular sets forth an acceptable means for complying with the rules governing
aircraft equipment installations in cases involving the substitution of technical standard order
(TSO) equipment for functionally similar TSO approved equipment.
2. CANCELLATION. AC 20-41, dated August 30, 1965, is cancelled.
3. REFERENCE REGULATIONS. Parts 23, 25, 27, and 29, and sections 21.95, 21.113, 21.115, and 43.13
of the Federal Aviation Regulations.
4. BACKGROUND. Under the referenced rules, the determination of compliance with the regulations may
require that an aircraft be flown for functional check of any replacement parts or installations.
There have been discussions relative to the possibility of substantiating the acceptability of
installations, without a flight check, when functionally similar TSO'd equipment is substituted for
previously approved TSO'd equipment. The acceptable means of compliance in paragraph 5 deals with
this question and is applicable to the evaluation of replacements under the alterations performance
rules of section 43.13, a minor change in type design per section 21.95, or supplemental type
certificate procedures of sections
21.113 and 21.115.
5. ACCEPTABLE MEANS OF CCMPLIANCE. In the case of an aircraft alteration involving the
substitution of TSO-approved equipment for functionally similar TSO'd equipment, an acceptable
means of compliance with applicable airworthiness regulation without the aircraft being flight
checked, is to:
a. Show, by means of ground functional tests, analyses, drawings, descriptive data or combination
of these that:
(1) The substitute equipment and its installation meet the airworthiness regulations which are
applicable to the equipment to be replaced;
(2) The connections (electrical, electronic, mechanical, or fluid) between the equipment under
consideration and other equipment in the aircraft either remain the same 0r, if these connections
are modified, the modification does not affect the TSO status of the equipment; and
(3) The radiation system (including transmission lines) and other electrical or electronic
aircraft equipment that connect to the equipment under consideration either remain the same, or if
modified, the modification does not adversely affect the per formance of such systems or equipment
and the subject equipment.
b. Include necessary information in the appropriate part of the Federal Aviation Administration
approved Flight Manual concerning any signif icant change in equipment capability as determined
from the evaluation outlined in items 5.a.
6. EXCLUDED EQUIPMENT. The substitution procedures provided by this circular should not be used
in connection with auto pilots, flight directors, iner tial navigation systems, stability
augmentation systems, stall prevention systems, tires, wheel-brake systems, or any other equipment
directly affecting flight controls or flight characteristics. Substitutions which affect equipment
in the cockpit should be evaluated by appropriate flight test personnel.
7. FLIGHT TESTS. Flight tests may be necessary, in some cases, to adequately evaluate the effects
of changes and this decision rests with the approving authority.
R.P. Skully
Director, Flight Standards Service
Washington DC

 

[waylon scudder]

CAN NON-TSO'D EQUIPMENT BE INSTALLED IN A TYPE-CERTIFICATED AIRCRAFT?

It is widely believed that all avionics equipment that is installed in a type certificated aircraft must have TSO authorization. The purpose of this pamphlet is to examine this idea by references found in FAA documentation. The scope of this discussion will be limited to aircraft with a standard category U.S. airworthiness certificate. To begin lets first take a look at the CFRs.

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

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. One means to insure this would be to only install TSO’d equipment. TSO’d equipment is equipment that the FAA has examined and determined that it meets the requirements of Part 23. Another way would be to review the requirements set forth for a particular type of equipment (i.e. communication or navigation radio) by referring to a particular TSO document. The TSO document will spell out the minimum performance standard for a type of equipment, usually by referencing an industry-standard organization’s documentation such as that of RTCA Inc. (Radio Technical Commission for Aeronautics). At this point in our discussion one might be overwhelmed by the process and choose the path of least resistance and go with the TSO’d equipment. Or one could look to the manufacturer of the equipment for information as to what standard the equipment was manufactured to. This information is typically found in the specifications section of the equipment’s installation manual. The idea that a piece of equipment meets the requirements of a recognized standard such as a TSO but not have the TSO authorization is backed up in FAA Order 8300.16A APPENDIX A. Definitions (10) Meet Minimum Technical Standard Order (TSO) Established Standards. Means that the equipment need not have TSO approval, but that it meets requirements set by the TSO.

The next topic that comes up in the discussion is whether or not the installation is required to be recorded on FAA Form 337 and whether it will require a field approval. These questions are answered by examining the requirements for the use of Form 337 and for field approvals. 14 CFR Part 1 Section 1.1 defines a minor alteration as an alteration that is not a major alteration. Some examples of major alteration are defined in Appendix A of Part 43. Unfortunately the installation of radio equipment is not appropriately covered in the appendix.

FAA Order 8300.16A Chapter 3 provides guidance as to determining if an alteration is major or minor. In this discussion it will be broken down into a series of questions the installer might answer to arrive at a designation of the alteration as major or minor.

General alterations:

• Does the proposed alteration have an appreciable effect on the certificated weight? (i.e. A change in the maximum takeoff weight limitations, minimum landing weight limitations, etc.)

• Does the proposed alteration have an appreciable effect on the certificated balance? (i.e. A change in the forward or aft center of gravity limits, etc.)

• Does the proposed alteration have an appreciable effect on the structural strength?

• Does the proposed alteration have an appreciable effect on the performance?

• Does the proposed alteration have an appreciable effect on the powerplant operation?

• Does the proposed alteration have an appreciable effect on the flight characteristics?

• Does the proposed alteration have an appreciable effect on other characteristics affecting the airworthiness?

Yes to any of the above questions: The proposed change is a major change in type design requiring the application for a Supplemental Type Certificate (STC).
Confirmed no to all: Continue.

• Is it possible that the proposed alteration might have an appreciable effect on the certificated weight? (i.e. A change in the maximum takeoff weight limitations, minimum landing weight limitations, etc.)

• Is it possible that the proposed alteration might have an appreciable effect on the certificated balance? (i.e. A change in the forward or aft center of gravity limits, etc.)

• Is it possible that the proposed alteration might have an appreciable effect on the structural strength?

• Is it possible that the proposed alteration might have an appreciable effect on the performance?

• Is it possible that the proposed alteration might have an appreciable effect on the powerplant operation?

• Is it possible that the proposed alteration might have an appreciable effect on the flight characteristics?

• Is it possible that the proposed alteration might have an appreciable effect on other characteristics affecting the airworthiness?

• Does the proposed alteration alter the wings?

• Does the proposed alteration alter the tail surfaces?

• Does the proposed alteration alter the fuselage?

• Does the proposed alteration alter the engine mounts?

• Does the proposed alteration alter the control system?

• Does the proposed alteration alter the landing gear?

• Does the proposed alteration alter the hull or floats?

• Does the proposed alteration alter the elements of an airframe including spars, ribs, fittings, shock absorbers, bracing, cowling, fairings, and balance weights?

• Does the proposed alteration alter the hydraulic and electrical actuating system of components?

• Does the proposed alteration alter the rotor blades?

• Does the proposed alteration change the empty weight or empty balance which results in an increase in the maximum certificated weight or center of gravity limits of the aircraft?

• Does the proposed alteration change the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, deicing, or exhaust systems.

• Does the proposed alteration change the wing or any fixed or movable control surfaces which affect flutter and vibration characteristics?

• Does the proposed alteration convert an aircraft engine from one approved model to another, involving any changes in compression ratio, propeller reduction gear, impeller gear ratios or the substitution of major engine parts which requires extensive rework and testing of the engine?

• Does the proposed alteration change the engine by replacing aircraft engine structural parts with parts not supplied by the original manufacturer or parts not specifically approved by the Administrator?

• Does the proposed alteration include the installation of an accessory which is not approved for the engine?

• Does the proposed alteration include the removal of accessories that are listed as required equipment on the aircraft or engine specification?

• Does the proposed alteration include the installation of structural parts other than the type of parts approved for the installation?

• Does the proposed alteration make any conversions of any sort for the purpose of using fuel of a rating or grade other than that listed in the engine specifications?

Yes or maybe to any of the above questions: The proposed change is a major alteration requiring approved data, recording of FAA Form 337 and a log book entry.
Confirmed no to all: Continue.

• Has the Administrator issued an Advisory Circular that requires the use of approved data for this installation/alteration?

Yes: Follow the guidance contained in the Advisory Circular.
No: Continue.

• Has the Administrator issued policy (HBAW, FSAW, etc.) that requires the use of approved data for this installation/alteration?

Yes: Follow the published policy.
No: The alteration is a minor alteration with no additional published guidance therefore the use of acceptable data is authorized and the alteration/installation must be recorded in the appropriate maintenance record. Follow the provisions of Part 43, 65 and/or 145 as appropriate.

Appliance alterations:

• Does the alteration affect the basic design of the appliance?

Yes: Continue.
No: The alteration is considered an appliance minor alteration.

• Is the alteration of the basic design of the appliance made in accordance with recommendations of the appliance manufacturer or in accordance with an FAA Airworthiness Directive?

Yes: Continue.
No: The alteration is considered a major appliance alteration.

• Does the change in the basic design of radio communication and navigation equipment approved under type certification or a Technical Standard Order have an effect on frequency stability, noise level, sensitivity, selectivity, distortion, spurious radiation, AVC characteristics or ability to meet environmental test conditions and other changes that have an effect on the performance of the equipment?

Yes: The alteration is considered a major appliance alteration.
No: The alteration is considered a minor appliance alteration.

 

[waylon scudder]

BTW, Jim was right years ago when he tried telling everyone on here from personal experience about TSO'd equipment.

 

[flyingron]

BTW, Jim was right years ago when he tried telling everyone on here from personal experience about TSO'd equipment.

It wasn't just Jim. Anybody who understood the FAA guidance knew TSO was neither a necessary nor sufficient condition to install things in an airplane.

 

[NordicDave]

Well, let me just dig this one out of the archives. I was notified today of this:
https://www.faa.gov/aircraft/safety/programs/sups/upn/media/2018/S20180315005_UPN.pdf

Which is an Unapproved Parts Notification specifically for VAL avionics. I have a VAL INS 429 installed in my plane....

I found the FAA’s language interesting in this document concerning VAL:

“The FAA encourages aircraft owners, operators, manufacturers, maintenance organizations, parts suppliers and distributors to inspect their aircraft and/or aircraft parts inventory for the VAL Avionics Ltd. articles referenced above. If the referenced articles are found, the FAA recommends that they be quarantined to prevent installation on a Type Certificated aircraft until a determination can be made regarding their eligibility for installation. “

They are are not saying “No” until approved, just they are not comfortable with the situation - as I’m reading it. Also cleverly shifts tort responsibility to the installer/owner should an accident occur. First thing plaintiff lawyer will state is “installed critical equipment contrary to FAA recommendations”.

 

[Bell206]

just they are not comfortable with the situation - as I’m reading it.

FYI: If I recall correctly, it had more to do with "marketing" this equipment for install on on TC'd aircraft (Part 3) plus some people were installing the equipment as a "replacement" vs using the Part 43 alteration process. There's a reason VAL has a detailed article on non-TSO alterations. If these VAL installs had actually been contrary to the regs or a safety issue an AD would have been issued for their removal vs a simple notice on reviewing install eligibility.

First thing plaintiff lawyer will state is “installed critical equipment contrary to FAA recommendations”.

Ha. More likely the 1st thing the plaintiff will claim is "...failed to properly inspect and maintain the aircraft..."

 

[weirdjim]

They are are not saying “No” until approved, just they are not comfortable with the situation - as I’m reading it. Also cleverly shifts tort responsibility to the installer/owner should an accident occur. First thing plaintiff lawyer will state is “installed critical equipment contrary to FAA recommendations”.

What I find even MORE interesting is that the FAA document is undated and Timbec's post is nearly a year old. So far as I am concerned, an undated document has absolutely no validity just like an undated annual has no validity.

JIm

 

[WannFly]

This needs to be a sticky.

Now, for new owners like me, we ask the Q to our IA and the straight answer we get is, nope, go experimental or everything has to be certified, wake I ain’t signing( over simplified statement, but true)

I think to install let’s say a JPI 830 and take the crappy gauges out in our 40 year old planes, a few things must happen

1. The burden of proof for meeting all those things highlighted above falls on the owner, I don’t even know where to start if I have to prove any of it.

2. Need an IA who will put his name on it

Because the above 2 is nearly impossible ... at least for people like me, the entire certificated industry is thriving

Wow.

 

[Bell206]

Because the above 2 is nearly impossible ... at least for people like me,

FWIW: that is somewhat true today. 30-40 years ago it was the opposite. With the declining numbers of experienced/older IAs, and the change in how IAs are authorized, you now have a "perfect storm" where, one, the current IAs don't have the time or facilities to pursue projects outside the "norm" or, two, don't know how to or want to pursue projects outside the "norm." Regardless, there still are APs and IAs that do. As an owner, if you educate yourself on these rules/policies and present them to your APIA in a proper manner, you may just get them on board with the others. What have you got to lose?

 

[unsafervguy]

This needs to be a sticky.

Now, for new owners like me, we ask the Q to our IA and the straight answer we get is, nope, go experimental or everything has to be certified, wake I ain’t signing( over simplified statement, but true)

I think to install let’s say a JPI 830 and take the crappy gauges out in our 40 year old planes, a few things must happen

1. The burden of proof for meeting all those things highlighted above falls on the owner, I don’t even know where to start if I have to prove any of it.

2. Need an IA who will put his name on it

Because the above 2 is nearly impossible ... at least for people like me, the entire certificated industry is thriving

Wow.

removing and replacing required equipment like engine gauges is where it gets a bit tricky. installing something that is not required,like a radio, it really falls on the approving A&P to determine if that part is acceptable for installation. BUT, when you get to things that are required by FAR and the TCDS you get into a bit stickier situation. hence, most a&P's take the line, for that it must be STC'ed. Its just to bad the FAA has taken the hard line on field approvals that they have. a little common sense and a good inspector can make life a lot easier.

 

[Bell206]

Its just to bad the FAA has taken the hard line on field approvals

FWIW: Ironically, it was a small number of GADOs/FSDOs back in the 80s and 90s that led to the change in field approval/STC rules. Some ASIs in keeping with the spirit of cooperation with the flying public, elected to field approve a rather interesting list of alterations. This was also the time of duplicate 337s where once one 337 was approved it could be used for multiple 337s thereafter with no additional approval required.

The problem came to the surface when these altered aircraft left their original areas and a new owner or whatever wanted to alter another aircraft using the same 337 and the "new" local FSDO ASI went WTF. Per our local FSDO seems all issues were traced back to this small group of FSDOs approving alterations "outside" their authority. So around 2002 or so they issued an Order that dropped duplicate 337s and drew the line at field approvals/STCs, plus prohibited certain field approvals all together.

Luckily it was tweaked a bit because it basically shutdown Alaska side of things for a spell and caused a whole bunch of added work for all other large operators like my day job company. It also gave an out for any other ASI not to sign any more field approvals or bump it to the next office which still exists today with some ASIs. Fortunately, there still are some ASIs that will sign stuff off.

 

[waylon scudder]

It wasn't just Jim. Anybody who understood the FAA guidance knew TSO was neither a necessary nor sufficient condition to install things in an airplane.

Yeah your right FlyingRon but there are way to many people that still don’t get it. Many of my (our) fellow Mech’s and IA’s chose to run away from this issue. If you or any other aircraft owner friend ever needs my assistance with installing or simply helping with the paperwork after installation please let me know. I’m in southern Missouri. I’m about to install a Garmin GTX335 and GTR225 in my son’s C150. The paper trail is pretty much the same for all aircraft.

 

[Bob turner]

New guy here. Note that it is July 2021. This thread motivated me to contact my old San Diego friend Jim Weir.

Let me add a bit - there is a thread on the Garmin GTR-200 - I do hope those guys see this.

I have three Cubs - two with the GTR-200. It is a great radio and it has superior intercom, display, and memory features, all critically important to me. It is not TSO, although it meets RTCA DO-186B specs.

It has a lightweight RF squelch circuit, which is not a problem anywhere in California except in the north pattern at my home airport, where it receives intermodulation from two SoCal frequencies - we hear clearances!

So I mentioned it to the FAA. The frequency allocation guy did not understand the principles of heterodyning, so that was a waste of time, but he brought the FSDO. The FSDO says that non-TSO radios cannot under any circumstances be used in standard category aircraft. They are calling the GTR a "bogus part." I have been verbally informed that I am in violation every time I fly one of these airplanes

Let me post this, then I will give you my take on all this.

 

[Bob turner]

I am awaiting a letter of investigation - an "LOI" in FAA-ese. It will specify the exact regulation(s) I am violating. So far, the verbal input has been rather circular, involving parts 21.8 and 21.9, a "job aid" for major/minor determinations (they maintain this 2 lb radio is a major alteration), and presumably the AC on bogus parts.

The good news for me, and owners of aircraft with KX 170s and Mark 12s, is that there is an advisory circular that clearly states that a communication radio that meets RTCA DO-186B can be considered as complying with 14 CFR part 23, and can be used for IFR. Their exact words are " An acceptable means of compliance . . ."
See AC 20-67B. One page long!

I will wave at you as they transport me to Guantanamo, but I think I have at least some ammunition for the appeal.

We, of course, have these radios in CAR4a airplanes, and do not fly them IFR, so in the very strictest sense the AC does not apply - but if it doesn't, then what does?

I mostly lurk on Super Cub, J3, and ChampDecathlon forums, but Jim's comments motivated me to join.

 

[Matthew Rogers]

I am awaiting a letter of investigation - an "LOI" in FAA-ese. It will specify the exact regulation(s) I am violating. So far, the verbal input has been rather circular, involving parts 21.8 and 21.9, a "job aid" for major/minor determinations (they maintain this 2 lb radio is a major alteration), and presumably the AC on bogus parts.

The good news for me, and owners of aircraft with KX 170s and Mark 12s, is that there is an advisory circular that clearly states that a communication radio that meets RTCA DO-186B can be considered as complying with 14 CFR part 23, and can be used for IFR. Their exact words are " An acceptable means of compliance . . ."
See AC 20-67B. One page long!

I will wave at you as they transport me to Guantanamo, but I think I have at least some ammunition for the appeal.

We, of course, have these radios in CAR4a airplanes, and do not fly them IFR, so in the very strictest sense the AC does not apply - but if it doesn't, then what does?

I mostly lurk on Super Cub, J3, and ChampDecathlon forums, but Jim's comments motivated me to join.

Why did you try to get my GTR-200 outlawed? If you had not asked, I could continue to live in ignorance.

 

[Bob turner]

I assume you are joking? I think when I am done there will be no more questions about non-TSO coms. Read the AC- it authorizes any comm radio that meets RTCA for IFR in a part 23 aircraft. One could assume they will have a difficult time excluding CAR4a aircraft operating VFR from that approval.

Jim mentioned that even transponders, according to FAR 91.215, do not have to be TSO'd. Read that FAR carefully, then see what the guidance in Order 8300.16A, Appendix A.10 says about "meet."

 

[Daleandee]

Jim mentioned that even transponders, according to FAR 91.215, do not have to be TSO'd. Read that FAR carefully, then see what the guidance in Order 8300.16A, Appendix A.10 says about "meet."

If I follow correctly (which is highly unlikely) I don't clearly see where you are going with the transponder reference in FAR 91.215 as it states:

"ATC transponder equipment installed must meet the performance and environmental requirements of any class of TSO-C74b (Mode A) or any class of TSO-C74c (Mode A with altitude reporting capability) as appropriate, or the appropriate class of TSO-C112 (Mode S)."

But I believe I do see where you are with Order 8300.16A Apendix A:

"Meet Minimum TSO Established Standards. Means that the equipment need not have TSO approval, but that it meets requirements set by the TSO."

So your take is that the "meets" doesn't mean TSO approval but rather that it "meets" the requirements set by the TSO.

Interesting ...

 

[Bob turner]

Not my take. Their words!

I think they have, from the start, considered this a major alteration. I have asked for their reasoning in writing. I believe (but am not sure) that they are considering a comm radio to be a critical system. I have two FAA documents defining "critical system" ready to go. Amazing what one can dig up with the Google.

 

[bradg33]

Not my take. Their words!

I think they have, from the start, considered this a major alteration. I have asked for their reasoning in writing. I believe (but am not sure) that they are considering a comm radio to be a critical system. I have two FAA documents defining "critical system" ready to go. Amazing what one can dig up with the Google.

Good luck to the FAA in proving that a comm radio is a "critical system," given that it's not strictly required equipment. And the FAA knows how to require, in the regs, that equipment meet a specific TSO - look at the transponder and GPS regulations that specifically cite to a TSO. The FAA hasn't required, in the regulations, that a comm radio meet a TSO (though a TSO exists).

 

[Bob turner]

They have defined a "critical system." Briefly, a system is critical if continued flight and successful landing is questionable.

Again, a TSO is specifically not required for transponder equipment under part 91.215. Transponders only need to meet the requirements. And in part 91.205 (com radios) TSO is not even mentioned.

I hope to get a hint as to what they think takes this into "major alteration" territory tomorrow. They ought to be able to cite something, since they have spent a month telling me it is major. The regulation is crystal-clear.

 

[Bob turner]

Deleted