CAR3 certified aircraft in a 2022 world

[Will Ware]

My 1946 Stinson 108-1 was and still is certified under CAR3. This aircraft was never and could not be certified under Part 23 as it doesn’t meet part 23 standards.

Im so frustrated by the BOX the FAA has created around vintage aircraft and general aviation as a whole. There are FEW modifications that can be done today because many old STCs are no longer supported, and new STCs will not be created because these vintage aircraft have such limited numbers the vendors will not spend the money.

Then I look in the neighboring hangar at the Experimental who can hang an dang thing they want on the airframe and operate in the same NAS as me simply because they are a 2” EXPERIMENTAL taped to the airframe.

It’s just plane unfair!

Now back to the CAR3 issue, when I want to install something, Im told “It has to be FAA/PMA approved” or “TSO” or something like that. Well when the aircraft was certified in 1946 there was non of that.

So, If you look at my CoA and POH they both state the aircraft was certified under CAR3 (NOT part 23), so the STANDARD of Airworthiness is compliance with CAR3.

Come on IA’s out here, let me hear your thoughts, but you have to acknowledge that CAR3 is STILL applicable and how does that dovetail into todays upgrades?

 

[TCABM]

What upgrade(s) are you seeking to accomplish? It’s one thing to get a field approval for something like a G5/GI275. It’s likely something entirely different to get a field approval for a one-off STOL kit.

 

[Will Ware]

Well a a little bit of a tangent from my post in the Avionics forum but replacing things like old automobile switches with new type switches that are being used in Experimental and they do have MIL spec. CAR3 simply states they must work! The new ones are NOT FAA/PMA approved, but in my mind comply with CAR3 standards

 

[Dana]

Sounds like you need to have a conversation with the IA who will be signing it off. I'm in agreement that any suitable switch should be acceptable per CAR3, but the IA also has to agree.

But if that last picture is the switch you want to install, well, it just looks wrong for an airplane built in 1946. And even though appearance is meaningless from a safety standpoint, it may be an easier sell if it looks more like the original.

 

[R.L.Mauzy]

I'm pretty sure that what you want to look at for the answer is part 43. If the aircraft is certificated I don't believe it matters if was Car 3 or Part 23, maintenance falls under part 43 from what I understand. Now if you are unable to find a part number that is the "correct" fit substituting with a field approval would be a trivial matter and that's where the original Car 3 would help. Just my humble opinion for what its worth ... if it's certificated Car 3 or Part 23 doesn't matter, maintenance rules (Part 43) would be the same.

 

[Will Ware]

Sounds like you need to have a conversation with the IA who will be signing it off. I'm in agreement that any suitable switch should be acceptable per CAR3, but the IA also has to agree.

But if that last picture is the switch you want to install, well, it just looks wrong for an airplane built in 1946. And even though appearance is meaningless from a safety standpoint, it may be an easier sell if it looks more like the original.

I will work with an AI for the agreement. As to the Old aircraft, that is not the look Im going for, think more Legend/CubCrafters, an update and mix of old and new

 

[Will Ware]

I'm pretty sure that what you want to look at for the answer is part 43. If the aircraft is certificated I don't believe it matters if was Car 3 or Part 23, maintenance falls under part 43 from what I understand. Now if you are unable to find a part number that is the "correct" fit substituting with a field approval would be a trivial matter and that's where the original Car 3 would help. Just my humble opinion for what it’s worth ... if it's certificated Car 3 or Part 23 doesn't matter, maintenance rules (Part 43) would be the same.

Good points, but lets dig just a bit deeper, there is nothing I have or can find that would “detail” the original switches that we installed, they could have been from a automobile or tractor for all I know so how would I even know the original specs? There is nothing in the TDCS, POH, equipment list etc.

Also would you have a reference in part 43 that would specify those requirements?

 

[R.L.Mauzy]

I will have to read through it later today to cite a specific article/paragraph ... from what I do recall off the top of my head is that the switches, as an example, you are talking about would not be an owner replaceable item. That being the case you would need your A&P to do this. I believe it would be easiest/best to ask his/her guidance as to the appropriate replacement.

I have a similar problem in the automotive world right now. Whilst I don't need to worry about certificated parts etc, I still have to try to find the closest original parts I can. I am doing a resto-mod on an exceedingly rare 1973 Chevelle (only 36 remain registered in the US last I checked) and finding parts for this beast is truly a nightmare. There are very few places that make very very few specific parts for it. As a result I've become very familiar with GM parts of the era and have to figure out and "make fit" sometimes as close to original as possible. The original owners manuals and repairs manuals just don't have any relevant info as the parts either don't exist or no one makes a specific replacement. I get around it by finding the next closest related item ... maybe a corvette or camaro or cutlass or regal part etc etc. sometimes I have to bite the bullet and custom fab something from scratch. In my mind that is where an old plane would be at, just with the added complication of using certificated parts.

I reference these FYI and I don't see anything in preventative maintenance that allows the switches to be owner replaced but then I could be wrong and not interpreting it correctly ...

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-C/part-43

https://www.faasafety.gov/files/gsl...Owning Your Own Aircraft [hi-res] branded.pdf

 

[Capt. Geoffrey Thorpe]

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-C/part-43/appendix-Appendix A to Part 43 ???

 

[schmookeeg]

You're an A&P, why not just assert your authority and "bet the cert" on your interpretation of things?

 

[j3cubcapt]

You're an A&P, why not just assert your authority and "bet the cert" on your interpretation of things?

Because it's a blurred line for a 70+ year old aircraft and if the FAA would make better regs that address aging aircraft than it would be easier


Sent from my iPhone using Tapatalk Pro

 

[Bell206]

Now back to the CAR3 issue, when I want to install something, Im told “It has to be FAA/PMA approved” or “TSO” or something like that.

To add to the above, I don't quite follow your issue with CAR 3 vs Part 23 as there is no direct link to them for the work you want to perform. As stated that is all under Part 43 regardless of the aircraft certification. And has been for many years.

As to what parts can be installed on a type certificated aircraft there are multiple threads on PoA that go into great detail. But suffice to say you, as an A&P, can install whatever part you want on an aircraft as long you follow the correct guidance. As to specific parts, most electrical parts fall under the Standard Part category and do not require any approvals. As to "experimental parts" there is no such regulatory category. Its merely a way for venders to stay legal under Part 3 and Part 21.

Perhaps take a moment to review some of the older threads and if you still have specific questions post them.

Because it's a blurred line for a 70+ year old aircraft and if the FAA would make better regs that address aging aircraft than it would be easier

How is it blurred? Maybe I'm missing something but Part 43 is pretty straight forward when it comes to performing any work on any aircraft.

 

[TCABM]

Have you reviewed AC 23-27, which provides guidance for substantiating parts or materials substitutions to maintain the safety of old or out-of-production general aviation (GA) aircraft, or other GA aircraft where the parts or materials are either difficult or impossible to obtain?

https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_23-27.pdf

 

[mondtster]

I will work with an AI for the agreement. As to the Old aircraft, that is not the look Im going for, think more Legend/CubCrafters, an update and mix of old and new

If Legend and Cub Crafters is your point of reference, perhaps it would be worth the effort to see how or if they get things like what you’re referring to approved. I’ll give you a hint - it’s not like what you’re imagining.

If anything, the “blurred line” referred to up the thread is blurred in a way that is favorable to make alterations and substitutions as desired but there are still some rules to play within.

 

[MauleSkinner]

Good points, but lets dig just a bit deeper, there is nothing I have or can find that would “detail” the original switches that we installed, they could have been from a automobile or tractor for all I know so how would I even know the original specs? There is nothing in the TDCS, POH, equipment list etc.

If “original” is what you’re looking for, Type clubs can often tell you which car manufacturer those parts came from.

 

[steingar]

If @Will Ware really wants to be able to freely modify his aircraft like an Experimental he can sell his Stinson, buy an Experimental and do exactly that.

 

[Magman]

The predecessor to AC 43.13-1 &2 was CAM 18.

I have heard that it was never cancelled and can still be used as a ref for CAR aircraft.

Perhaps Bell or someone will confirm or deny?

 

[Doug Reid]

I think you would be best to restore your 108 and add some modern avionics. These airplanes are still very popular.
There are currently two 108 restorations at a shop here in Thomasville, NC.
One was recently completely rewired, and as far as I know, it is being restored to circa 1946 condition except for new radios ( hiding behind a Narco Superhomer removable cover ).

Reference AC43.13-1B, Chapter 11 for electrical data.

 

[Bell206]

I have heard that it was never cancelled and can still be used as a ref for CAR aircraft.

As I recall only certain certification CAMs were retained after the switch to the FARs and ACs with the rest deactivated. I believe there is an old AC that lists those docs?? CAM 18 is still listed as a historical reference in the DRS since there are aircraft flying with worked performed under that manual.

 

[Dan Thomas]

If @Will Ware really wants to be able to freely modify his aircraft like an Experimental he can sell his Stinson, buy an Experimental and do exactly that.

Or move to Canada and register it in the Owner-Maintenance category.

 

[j3cubcapt]

If @Will Ware really wants to be able to freely modify his aircraft like an Experimental he can sell his Stinson, buy an Experimental and do exactly that.

I have researched Experimental Exhibition which is a viable path


Sent from my iPhone using Tapatalk Pro

 

[MarkH]

Well a a little bit of a tangent from my post in the Avionics forum but replacing things like old automobile switches with new type switches that are being used in Experimental and they do have MIL spec. CAR3 simply states they must work! The new ones are NOT FAA/PMA approved, but in my mind comply with CAR3 standards

I cannot offer much valuable comment, since I am not qualified to do so. But I can ask as specific question that could either help or make things even more confusing.

Wouldn't a switch be considered a standard part?

In a seminar by Mike Busch, he mentioned that parts like resistors and capacitors are considered standard parts and can be bought at a Radio Shack (if you can find one that sells more than cell phones I guess) as long as it meets the specs of the resistor you are replacing. As someone who has done professional electronics work, I don't see how a switch would be different (but I cannot comment on the perspective of the FAA).

The seminar for reference:

 

[Bell206]

Wouldn't a switch be considered a standard part?

Yes in most circumstances so long as it meets a governmental/industry specification or standard and can be identified and conformed. Don't know the current status of Radio Shack parts but buying name brand components at an electrical supply distributor usually takes care of that requirement. And the product catalogue usually contains the conformity info and mfg. standard/spec.

 

[Half Fast]

Wouldn't a switch be considered a standard part?

Yes, but....

Specifications for a mechanical switch can be more complicated than you may think. There’s more to a switch than the number of poles and the amperage rating. Rated number of cycles, contact resistance, contact bounce, sealing against explosive atmosphere, materials used, enviro specs like vibration, shock, humidity, fungus growth, etc., are things that could be important depending on the application.

How many of those things were considered in the original part selection? Who knows? You have to apply some judgment and not just grab any “similar” part you find. You may need to remove a working switch and make a few measurements to ensure your new part behaves the same.

So yes, it’s a standard part, but selecting the correct replacement might not be trivial.

 

[Capt. Geoffrey Thorpe]

It would be important to have only explosion proof switches since they are likely mounted close to the ash tray.

 

[Half Fast]

It would be important to have only explosion proof switches since they are likely mounted close to the ash tray.

Or next to the cigarette lighter.

 

[Bell206]

So yes, it’s a standard part, but selecting the correct replacement might not be trivial.

In most small aircraft its pretty straight forward in dealing with standard parts and replacements as there are a number of guidance documents that keep you inline. Where it gets more involved is when an OEM takes a standard part and "customizes" it in some fashion. But even that can be dealt with usually no issues. However, when you get into the solid-state systems it does take a more involved review as you stated above to ensure the replacement component plays nice with the system as a whole.

 

[kgruber]

Even the King Air 90 is a CAR3 airplane

 

[Dan Thomas]

Wouldn't a switch be considered a standard part?

No. Especially Radio Shack stuff. The typical switch has an AC voltage and current rating, possibly because those numbers look better. 60 Hz AC passes through zero 120 times a second, which tends to break any arc forming as the contacts open, limiting burning of the contacts. With DC, an arc can start and burn for many microseconds before extinguishing, and that wrecks the switch in short order. It's much worse with inductive loads like motors or solenoids. Those generate a voltage spike when disconnected. It's why the big, heavy contacts in starter contactors burn out and cause starting issues.

DC-rated switches cost more, so the typical retailer won't carry much stuff like that. An industrial electrical supplier is a much better bet.

 

[Papa Pilot]

Have you reviewed AC 23-27, which provides guidance for substantiating parts or materials substitutions to maintain the safety of old or out-of-production general aviation (GA) aircraft, or other GA aircraft where the parts or materials are either difficult or impossible to obtain?

https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_23-27.pdf

FWIW
Last summer at OSH I asked the good folks at the uAvonix booth if there was a path to installing the SkySensor on certified planes. (I already had the SkyBeacon and wanted the complementary LED light on the right wing.) The guidance they gave me (which came to them via the FAA) was that I could install the SkySensor under AC 23-27 with a simple logbook entry. They advised against a 337.

The rational was that the SkySensor was a position light replacement, and since the SkySensor met the performance requirements of nav lights, it was an acceptable replacement under AC 23-27. The FAA didn't seem to be bothered by the fact the "nav light" also had a GPS sensor, an ADS-B in receiver and Wi-Fi.

Keep in mind the SkySensor is not TSO'd.

 

[Bell206]

I could install the SkySensor under AC 23-27 with a simple logbook entry.

Or you could install it as a minor alteration without the limitations of AC23-27. This was discussed in a prior thread. The only possible issue I see is any EMI interference with existing indicators, etc which can be checked and dealt rather easily as well.

Keep in mind the SkySensor is not TSO'd.

FYI: while lack of a TSO does not prevent installation, the position light function does meet TSO requirements which is important as position/collision lights need to meet a certain lumen and visibility depending on year built. Since this light meets those requirements it's a non-issue.

 

[Silvaire]

A lot of this boils down to an A&P/IA not willing to exercise their authority in regards to a repair or alteration being minor rather than major. Aside from the regulations, which are pretty clear, a mechanic also faces a type of peer review where someone may come along later and claim it's a violation and that the log entry isn't good enough. But if you look closely at what the definition of a major repair or alteration is well, the majority of this stuff just doesn't fall into that category. It doesn't bolster confidence when you see STC's for clamp on sun visors from companies like Rosen but they probably do it mostly to eliminate any question marks

 

[rotormatic1]

The sun visor mfg does it so they can have a production approval for the part...

 

[Bell206]

when you see STC's for clamp on sun visors from companies like Rosen but they probably do it mostly to eliminate any question marks

Vendors will sometimes use the AML-STC process when they have a product that can be used on different aircraft. The AML process allows a single base-line design approval to be used over multiple type certificates vs the repetitive/specific design approval required for the PMA process. ACO guidance actually points you in this direction as it saves time and money. This is why it's important to review each STC to see if it truly is a major alteration or not as the STC itself is not a valid trigger. Once a vendor obtains this AML-STC design approval from the ACO, then its off to the MIDO to get a production approval of their choice.

 

[Stewartb]

Read CAR3 and meet those standards. You are not required to do anything more. Don’t read anything into it that isn’t written.

 

[hindsight2020]

A lot of this boils down to an A&P/IA not willing to exercise their authority in regards to a repair or alteration being minor rather than major.

Of course that is the root of this problem, in practice, at the end of the day. You cant say that around the guild, lest you find yourself with sand in your virtual tank around here.

I say, by all means stipulate their aversion, you cant compel them to behave differently in present circumstances. But free our hobby from their pearl clutching, it's stagnating the place to death. If their grievance had any statistically significant safety weight behind it, we'd be ducking litters of crashing EABs on our suburban streets on our way to work. Alas, we dont.

Experimental cuts them out of their feared "line of custody" so they can move along and sleep better at night. Which i advocate should be an optable standard for ALL piston aircraft under 6k mgtow chosen to be operated by an owner on a non-revenue basis. In fairness to AP, its really not them holding up the show on that front, it's the OEMs which will never let primary noncommercial see the light of day. If the 4 seat market was in the same planet as 2 seat in the EAB spectrum, id say leave everything alone and watch this dynamic self limit in the time it takes rubbing alcohol evaporate on a wound.

 

[Dan Thomas]

Maybe the FARs need an Appendix like the one Transport Canada gives us in the CARs:

Appendix A - Criteria for the Classification of Modifications and Repairs
Content last revised: 2002/06/01

(1) General
The following criteria outline a decision process for assessing the classification of a modification or repair.

Information Note:

For each issue it shall be determined whether the modification or repair to be accomplished could have other than a negligible effect on those characteristics contained in the definitions of "Major Modification" and "Major Repair", pursuant to section 571.06 of this standard. The following questions are answered with either a YES or NO response. A YES answer to any individual question indicates that the modification or repair shall be classified major.

(2) Criteria

• (a) Operating Limitations
• Does the modification or repair involve a revision in the operating limitations specified in the approved type design?
• (b) Structural Strength
  Information Note:
• The questions contained in this paragraph shall be applied to alterations of an airframe, engine, propeller, or component.
• Does the modification or repair alter:
  • (1) a principal component of the aircraft structure such as a frame, stringer, rib, spar, skin or rotor blade?
  • (2) a life-limited part or a structural element that is subject to a damage tolerance assessment or fail-safe evaluation?
  • (3) the strength or structural stiffness of a pressure vessel?
  • (4) the mass distribution in a structural element?
    • Information Note:
    • This might involve the installation of an item of mass that would necessitate a structural re-evaluation.
  • (5) a containment or restraint system intended for occupants or the storage of items of mass (e.g. cargo)?
  • (6) the structure of seats, harnesses, or their means of attachment?
• (c) Powerplant Operation
• Does the modification or repair:
  • (1) affect the power output or control qualities of the powerplant, engine, propeller, or their accessories?
  • (2) alter the approved operating limitations?
• (d) Performance and Flight Characteristics
• Does the modification or repair involve alterations that:
  • (1) significantly increase drag or exceed aerodynamic smoothness limits?
  • (2) significantly alter thrust or power output?
  • (3) affect stability or controllability?
  • (4) induce flutter or vibration?
  • (5) affect the stall characteristics?
• (e) Other Qualities Affecting Airworthiness
• Does the modification or repair:
  • (1) change the information on, or the location of, a placard required by the type design or an Airworthiness Directive?
  • (2) alter any information contained in the approved section of the aircraft flight manual or equivalent publication?
  • (3) affect the flight-crew's visibility or their ability to control the aircraft?
  • (4) affect egress from the aircraft?
  • (5) reduce the storage capacity of an oxygen system, or alter the oxygen rate of flow?
  • (6) affect flight controls or an autopilot?
  • (7) alter an electrical generation device, or the electrical distribution system between the generating source and either its primary distribution bus, or any other bus designated as an essential bus?
    • Information Note:
    • The electrical distribution system includes its associated control devices, and all its protection devices.
  • (8) reduce the storage capacity of the primary battery?
  • (9) affect a communication system required by the approved type design?
  • (10) affect instruments, or indicators that are installed as part of a system required by the approved type design?
• (f) Other Qualities Affecting Environmental Characteristics
• Does the modification or repair increase aircraft noise levels or emissions?

https://tc.canada.ca/en/corporate-s...es-m-canadian-aviation-regulations-cars#app-a

 

[Bell206]

Maybe the FARs need an Appendix like the one Transport Canada gives us in the CARs:

There already is a similar reference in the FARs by applying the Part 1 definitions of major repair/alteration to the major repair/alteration lists in Part 43 Appx A. It provides the same guidance as the TC list. In addition there are several more guidance docs that build on these references if needed. However, in my opinion its not the lack of references that is the problem with the major/minor question but the subjective nature of the issue just like defining what is airworthy. Everyone has their own comfort zone with both.

it's the OEMs which will never let primary noncommercial see the light of day

FYI: what killed the primary non-commercial movement was their attempt to piggyback it on the Part 23 rewrite which was the wrong venue. Plus the fact there was no viable reversal process to return an aircraft back to its original standard category. Which as I recall was one of the issues that hindered the growth of the Owner Mx category in Canada. Personally I’m all for it as are other mechanics, but those were 2 huge hurdles it couldn’t cross especially the 2nd one.

 

[Dan Thomas]

FYI: what killed the primary non-commercial movement was their attempt to piggyback it on the Part 23 rewrite which was the wrong venue. Plus the fact there was no viable reversal process to return an aircraft back to its original standard category. Which as I recall was one of the issues that hindered the growth of the Owner Mx category in Canada. Personally I’m all for it as are other mechanics, but those were 2 huge hurdles it couldn’t cross especially the 2nd one.

If costs keep rising, the pressure will grow to create the US version of O-M. Otherwise, only the rich will fly. Owning an O-M and putting up with its travel restrictions or loss of resale value is preferable to many here, especially for the mechanically inclined who are willing to follow instructions in the manuals. The loss of resale is easily offset by the savings in maintenance labor costs. Easily. It doesn't take too many $2K annuals on a basic airplane, or the Cessna/Piper parts prices, to make O-M attractive.

 

[Bell206]

especially for the mechanically inclined

to make O-M attractive.

In theory I would agree. But in practice I really haven't seen that especially when I moved into owner-assisted work. In my experience, while there are a hardcore group of owners that currently perform all the maintenance they can on their aircraft, a larger group barely scratch the surface with doing their oil changes or other routine maintenance per Part 43(A)(c). I just don't see those numbers increasing much in the big picture along with the possibility of actually reducing the options for OM aircraft if the current support system restricts those type aircraft from access. Do TC repair stations and other TC entities work on OM aircraft or still provide services?

Regardless, I do think it will appeal to a certain group that already think the system is broke but those type owners exist now paying for 20 min annuals and such. However, unless owners get another grassroots movement going like there was for the PNC attempt it will never materialize under the current FAA funding and priorities. I thought Primary Non-Commercial would have been an excellent retirement gig by offering consulting and tool rental to offset my weekly beer costs. But such is life in the big city...now I just post for free on PoA and drink cheaper beer.