V8 engine Cessna 172

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BBerson

Light Plane Philosopher
HBA Supporter
ASTM engine standards are virtually copies of Part 33. Same with part traceability standards.
The big engine companies (Rotax) write the rules to restrict competition.

Vigilant1

Well-Known Member
Lifetime Supporter
The big engine companies (Rotax) write the rules to restrict competition.
--Existing engine companies win by creating a "wide moat".
-- The FAA wins by being able to portray themselves as concerned with safety as it top concern. And being able to continue business as usual, maintaining present budgets, etc.

It's important not to confuse "documentation" with "safety."

BBerson

Light Plane Philosopher
HBA Supporter
but because the FAA requires any propeller to undergo its own certification as an aircraft propeller... THEN you can apply for an STC to install that certified propeller on some airplane that it wasn't originally TC'd on.
Right. Because commercial airplanes need a type certificate (part 23)
Props are type certificated under Part 35
Engines are type certificated under Part 33
Rotorcraft part 27

skydawg

Well-Known Member
a lot of incorrect speculation here, fellas, but can only speak to our project. The V8 STC for the C172 was already issued a FAA G1 issue paper, which essentially approves the cert plan and cert basis for the STC. AS far as prop cert goes, a prop for a part 23 cert'd aircraft must have its own cert, but there is a lot more besides how the prop is physically made or tested, for certification..... most prop manufacturers are busy enough without the headache of certifying their product.... its expensive, a relatively small customer base to buy it, and liability risk.

Again, both certs are expensive, but possible. I think you'll see more experimental stuff sliding over to LSA with LSA rewrite in the works, and experimental, as exhibition has been about same as AB ops limits. Other changes that may be similar to Canada's owner maintained category (wherein owner can convert to essentially similar limits as AB) without considerable engineering mumbo-jumbo, will likely be considered....mostly the GA piston fleet is disappearing with little replacements, and need ways to keep them flying.

Airplanes and components are certified on a basis of some specific regulations, such as 14 CFR part 23, 33, JAR, EASA, CAR3..... depending on component. Certification basis are specific, but FAA & EASA now consider what's called 'alternative means of compliance', wherein an applicant can propose another set of standards, such as ASTM requirements for a prop, for example....or propose their own set of standards as long as they can show its equivalent to the standard regulation. This is often done with newer technologies, such as electric aircraft, where the old regulations are not really applicable... such as an engine requiring a fuel shut-off method or demonstrating performance showing compliance of a part 23 reg requiring oil temps stay within norms on hot day climbs.

The cert rules are absurd and boring. But there is a lot of misunderstood info floating around, and I'd recommend reading the actual regs for a better understanding of what's possible or not.

AS far as putting an experimental, such as a Vans AB, in to restricted category, cant be done..... restricted requires aircraft be previously certified. Its designed for aircraft that are modified for a specific mission, say a helicopter with a spray device to dust crops. Getting an STC, or modifying the TC, would not be efficient, especially if the sprayer was only one one or a few copters. The restricted category allows the copter to fly out of its TC configuration, and restricted can have many ops limits.

TFF

Well-Known Member
Most of us are greedy and only think in FAA terms. Yes the transfer of certification is possible but 90% people on this website are probably US. The ones who aren’t know way more about US rules than the other way around. Plan, we don’t need no stinken plan. Mixing and matching regs does confuse a lot. The Canadian recertification of regular certified planes will never happen in the US with 90% of all airplanes in the world here. Everyone would jump on it and have the same problem as the warbird people trying to sneak in stuff not originally intended. It would end up trashing GA here once the FAA slammed the door.
Besides liability, what would it take to get this to the door of my house as either a homebuilt or certified engine? That is the question everyone would want to know.

rv6ejguy

Well-Known Member
Other changes that may be similar to Canada's owner maintained category (wherein owner can convert to essentially similar limits as AB) without considerable engineering mumbo-jumbo, will likely be considered....mostly the GA piston fleet is disappearing with little replacements, and need ways to keep them flying.

Airplanes and components are certified on a basis of some specific regulations, such as 14 CFR part 23, 33, JAR, EASA, CAR3..... depending on component. Certification basis are specific, but FAA & EASA now consider what's called 'alternative means of compliance', wherein an applicant can propose another set of standards, such as ASTM requirements for a prop, for example....or propose their own set of standards as long as they can show its equivalent to the standard regulation.
As far as I know, the FAA has been completely unresponsive to an OM category as we have in Canada. Some of my American friends have proposed this but it's gone nowhere.

Again, it's just speculation that the FAA will allow an ASTM type standard as I mentioned before on engines going into certified airframes. You can't go ahead on this until they say they will allow it. They have shown much more acceptance on the avionics side but little on the engine side to date.

You've impressively come a long ways with your package and the STC however it seems you don't have a clear path on which direction you'll take this. Project and liability costs would seem to be a major obstacle given the market size available for this weight and hp class of engine. I don't see a favorable ROI here.

Bottom line, you can talk about it but that doesn't accomplish much. You either forge ahead with a solid business plan or wrap it up- only 2 choices here.

pfarber

Well-Known Member
I have an FAA certified product that I manufacture, so I can speak here from experience. The overall answer to your question (if you had asked that question to me about my product) is:

"The two years and $25K that it took just to get the finished product certified (after I had designed, tested and set up the manufacture), with all the initial paperwork, plus the money and time it takes to do the paperwork on every one I build from then on." That's on a$499 retail product with one mechanical moving part, that will not crash an airplane even if every part of it fails at the worst time.

Garmin makes a product that people in an airplane are relying on for their life in some circumstances. Their product has hundreds of separate electronic components which can burn out or go bad, and their product probably cost them $500K to get certified. Garmin's answer also includes something my answer does not, which is "The enormous cost of an insurance policy that covers the level of liability which comes with a flight-critical aircraft instrument". Thank you for some hard numbers. But let me make one small correction. NONE OF THIS HAD ANYTHING TO DO WITH LIABILITY!!!! The cost of certification is a thing, EVERWHERE. None of the$25k covered one iota of LIABILITY. You paid for the CERTIFICATION PROCESS.

Being FAA 'blessed' does NOT protect you from LIABILITY. It simply means that you can install it legally on certified aircraft. If I am wrong, please show me the 'FAA liability get out of jail free card' that you were given.

Now, if you gave us your annual product liability insurance cost and admin costs to run the backend for a year for liability compliance THEN you would be telling us the cost of liability of protection.

I can't believe that you think FAA certification is the same thing as liability protection. Wow.

Also, there is NOTHING in the FARs that require liability insurance. A keyword search of Electronic Code of Federal Regulations (eCFR)

shows no hits for insurance or liability.

Do I agree the FAA makes the cost of CERTIFIACTION unreasonable? Yes. But that's not LIABILITY.

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pfarber

Well-Known Member
@pfarber, as HBA’s most experienced and foremost critic, do you have any constructive criticism for this project, or do you just want to #&*# on it?

@skydawg, next time I’m on your side of town, the beer’s on me. This is very cool.
If asking questions and having a conversation is being a critic then oh, well. I am not going to give out participation ribbons for something I believe to be incorrect. If I see something that I believe to be incorrect I will ask about it. Now some people will consider being asked a question as a personal attack, but that's really not anything I can solve. The question will still be asked.

One guy just posted that the cost of certification is the same as liability costs... should I not ask for a clarification? Because it's not.

People read all sorts of things into a forum post. Somehow they can devine a made up 'angry tone' when asked a question. If I had a superpower, 'forum emotions man' would be a pretty lame one.

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Dana

Super Moderator
Staff member
The other part that will make this all too expensive for certification is that you'd be required to show traceability of all engine components as passing process control and quality control during manufacture unless the FAA will waive that requirement and allow you to use a less stringent ASTM cert as LSA regs allow I believe. Using 3rd party parts here (GM manufactured) probably won't fly with the FAA without a lot of NDT and QC checks to verify part quality and compliance. The certified paper trail required will up the cost substantially.
What sucks is that GM's QC procedures nowadays are more stringent and more effective than any FAA certification requirements. I work for a company that makes both automotive and aerospace components (we sell bespoke parts to both Boeing and GM, as well as pretty much every other auto and aircraft maker in the world), and we have 100% traceability of every component that goes into our products. But, although GM no doubt could easily deal with the requirements to meet FAA standards, it's just not worth it to them for the miniscule aircraft market... and without their cooperation, certification ain't gonna happen.

I can't believe that you think FAA certification is the same thing as liability protection.
But I'd bet that certification would substantially reduce the cost of liability protection.

Pops

Well-Known Member
HBA Supporter
Log Member
I installed VW of America's computerized measuring equipment in their QC departments for measuring all of their body panels. Body panel parts were measured and scraped were you could not see the reason with your eye. I don't believe any GA aircraft manufacture could have any better QC of their aluminum airframe parts.

pfarber

Well-Known Member
But I'd bet that certification would substantially reduce the cost of liability protection.
That would be up to the insurance company, right? But the FAA has ZERO liability requirements for certification.

I linked to the all the rules re: FAA PMA (ie who can actually make parts) and not ONE mention of insurance or liability.

My point is that someone claiming to 'have knowledge' of the high cost of LIABILITY didn't realize the FAA costs had nothing to with liability. That's just the cost to get the part on the plane. Not to insure against it.

Something like fuel STC would have a laiblity cost, but evidently its not so onerous that they can't sell it for a few hundred dollars. And I think we can agree that cost of a 'certified' part vs an 'E/AB' only part is really up to the manufactuer, not the liability costs. I can still sue an maker of a certified part just as easily as a part for an E/AB. The FAA provides no protection.

BBerson

Light Plane Philosopher
HBA Supporter
a lot of incorrect speculation here, fellas, but can only speak to our project. The V8 STC for the C172 was already issued a FAA G1 issue paper, which essentially approves the cert plan and cert basis for the STC.
What is the purpose of the STC for N72CX? Registration now shows type certificate none, Experimental.
Why would the FAA issue a supplemental type certificate for an experimental? Or will the original type certificate be restored?
.

rv7charlie

Well-Known Member
Ooh ooh, can I answer?

STCs are typically intended to apply to a group of a/c. In order to prove viability of the proposed STC mod, you need to fly it. Can't fly it on a std a/w cert. Make sense?

BBerson

Light Plane Philosopher
HBA Supporter
Make sense?
Nope.
The experimental certificate is to prove viability of the proposed mod to fly it temporarily and then put it back in standard with the original type certificate amended by the STC.
But the OP said he wasn't interested in the liability of type certificated standard aircraft, I think.

rv7charlie

Well-Known Member
Not the way I read what he posted; to me it sounded like he just wasn't interested in selling, *in the USA*. US cert can have usefulness in other countries...

rv6ejguy

Well-Known Member
We're working with the Twin Commander owner now to replace the mechanical FI and mags on his Orenda engines. Will be an interesting project.