DarkAero

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mcrae0104

Well-Known Member
HBA Supporter
Log Member
What exactly is you fear if a reduction in the 51% rule?
I don't fear a change to the rule. I just don't think you're likely to get any better, practically speaking. Trying to push for a better position than we already have (which is pretty fantastic in the broader historical and geopolitical context) could invite more scrutiny or agitate those who don't want us to have this freedom.

Would you please clarify what you want the rule to be? And if it's substantially less than 50%, would it not be inappropriate to call the category Experimental, Amateur-Built? Wouldn't it be more like an uncertified commercial aircraft product, some assembly of which might've been performed by the customer? Couldn't Cirrus offer an SR-22 in this category, bypassing all of the certification requirements simply by having the customer come and screw in the instrument panel and install the seats?

BBerson

Light Plane Philosopher
HBA Supporter
I think the Acting FAA Administrator at Airventure said the category might not include the word "experimental".

Rik-

Well-Known Member
What I read you write was that you remembered a new Cessna 172 did cost US$40k. I did then look up what year matched that price. Is it? What inflation adjuster have you used then?$40,000 in 1981 is equivalent in purchasing power to about $113,182.84 in 2020, a difference of$73,182.84 over 39 years. The 1981 inflation rate was 10.32%

12notes

Well-Known Member
Log Member
What inflation adjuster (factor) have you used then?

If your US $398,000 price is right the Cessna is spot on the inflation factor I have used. (M2 monetary inflation.) Since we're talking about the price of a consumer product, I used CPI. M2 is a measure of money supply, and, while it is related to inflation, the actual relationship is convoluted, and doesn't correspond to actual price differences or purchasing power. For price comparisons over time, CPI is the inflation rate to use. https://www.nasdaq.com/articles/confusing-connection-between-m2-and-inflation-2009-12-16 Rik- Well-Known Member I don't fear a change to the rule. I just don't think you're likely to get any better, practically speaking. Trying to push for a better position than we already have (which is pretty fantastic in the broader historical and geopolitical context) could invite more scrutiny or agitate those who don't want us to have this freedom. Would you please clarify what you want the rule to be? And if it's substantially less than 50%, would it not be inappropriate to call the category Experimental, Amateur-Built? Wouldn't it be more like an uncertified commercial aircraft product, some assembly of which might've been performed by the customer? Couldn't Cirrus offer an SR-22 in this category, bypassing all of the certification requirements simply by having the customer come and screw in the instrument panel and install the seats? I do not know the #. I do know that I can read numerous threads on HBA about potential buyers of an aircraft kit that are A. Concerned about meeting the 51% rule. B. Worried about qualifying for the “repairman certificate” due to this 51% rule. C. Don’t want anyone else getting credit for their work, even though they are wanting to sell the kit. D. People considering scraping a project due to the fact that they could not meet the 51% rule. So if the goal is to get more planes into the air then we need to remove obstacles in order to achieve this. So, if this magical 51% didn’t exist as a requirement a lot more planes could possibly be flying rather than residing within this limbo state. There might be more hope for that builder that cannot find the time to do 51%, or the project that they can afford will work for them as this rule will not interfere with their mission of one day owning and flying their plane. Remember in this demographics, more rules means more cost. Cirrus succeeds because there are buyers at the 750k range that enable both Cirrus and the buyer to be happy. Carbon Cub succeeds at selling a 300k cub because there are buyers at that level. Their demographics are not that of a home builder market. You have to know your market and their behaviors in order to meet their needs. Vans and others are offering an SLSA so there is a path for an uncertified factory built plane. BJC Well-Known Member HBA Supporter Marc Zeitlin Exalted Grand Poobah I do not know the #. I do know that I can read numerous threads on HBA about potential buyers of an aircraft kit that are A. Concerned about meeting the 51% rule. B. Worried about qualifying for the “repairman certificate” due to this 51% rule. C. Don’t want anyone else getting credit for their work, even though they are wanting to sell the kit. D. People considering scraping a project due to the fact that they could not meet the 51% rule. You are making the assumption that because there are people that are concerned about these things, that it is those things that's causing a problem. I would argue that the problem in almost all of the cases you mention, as it was in a number of very recent and still active threads, is that people don't understand the "major portion" rule, how it applies to kits and plans built aircraft, and how it applies (or doesn't) to getting the Repairmans Certificate. Once the folks with those concerns have the "major portion" rule explained to them, and understand how things actually work, they come to understand that in the vast majority of cases (and almost always THEIR case), there's no issue. So if the goal is to get more planes into the air then we need to remove obstacles in order to achieve this. It is a minuscule proportion of E-AB aircraft that have any issues at all with the "major portion" rule. So attacking something at the tail end of the histogram is not going to substantially change the # of aircraft that get built and flown. So, if this magical 51% didn’t exist as a requirement a lot more planes could possibly be flying rather than residing within this limbo state. That's a straw man, as indicated above. There are a zillion projects sitting around, not being completed, but it's most certainly NOT because folks are worried about getting the AC or RC for them. It's because there are far fewer folks that like to build these days than there were 20, 30, or 50 years ago. It's hard to give away Long-EZ projects for 1/2 the price of the materials in them, even when they're 70% complete. For someone that wants to invest$30K to finish them, they're GREAT deals. But most folks don't want to do the work.

There might be more hope for that builder that cannot find the time to do 51%, or the project that they can afford will work for them as this rule will not interfere with their mission of one day owning and flying their plane.
If someone wants to own and fly their own plane, and do it in a short period of time, building a plane is exactly the wrong path. They should just purchase a flying, completed E-AB aircraft. In most cases, they'll get the plane for the price of materials and get all of someone else's labor basically for free. There are SOME aircraft that go for a premium, but they're few and far between.

I disagree completely that relaxing the "major portion" rule is a way to get more airplanes in the air, and more pilots flying them.

Somehow, a discussion of the "DarkAero" kits morphed into a discussion of the possibility of low cost composite kits, and now to the rationality of the "major portion" rule...

BJC

Well-Known Member
HBA Supporter
Somehow, a discussion of the "DarkAero" kits morphed into a discussion of the possibility of low cost composite kits, and now to the rationality of the "major portion" rule...

BJC

BBerson

Light Plane Philosopher
HBA Supporter
The topic was low cost composite kits at original post.

Staggermania

Well-Known Member
HBA Supporter
Somehow, a discussion of the "DarkAero" kits morphed into a discussion of the possibility of low cost composite kits, and now to the rationality of the "major portion" rule...
I was wondering when someone would notice.

It seems to me that Cluttonfred was lamenting the dirth of affordable composite aircraft kits.

Staggermania

Well-Known Member
HBA Supporter
I think that what is required is a quantum leap in materials science. Composites, as they exist today, will always require either extensive labor, or extensive automation.

I imagine one day some sort of exotic nano-material will be developed that could utilize 3D printing, or maybe even roto-molding such as is used for plastic products like kayaks.

Even then, you’ll still have a limited market for whatever craft you put together, unless you create the “iPhone” of aircraft.
I posted this earlier, but it got lost in the “drift”

cheapracer

Well-Known Member
Log Member
I think that what is required is a quantum leap in materials science. Composites, as they exist today, will always require either extensive labor, or extensive automation.

.
Well I happen to disagree. The only bugbear to me is that CF is still a little expensive, other than that, a number of simple aluminium builds can be directly replaced with CF sheeting, yes, 'black aluminium'.

Not everybody wants or needs a sleek machine.

I imagine one day some sort of exotic nano-material will be developed
They are now adding a teaspoon or 2 of Graphene to Carbon Fiber mixes with spectacular results.

https://www.core77.com/posts/25262/carbon-fiber-and-graphene-two-great-tastes-that-taste-great-and-become-even-stronger-together-25262

There is a misconception that 51% means you have to build 51% of the craft, incorrect, it is that you need a 51% build understanding/repair ability of your own craft.

Lets say your craft has 1000 rivets, you don't have to pop 510 rivets yourself, you only have to demonstrate that you have the skillset to repair that area, to prove you are capable of maintaining and repair of those 1000 rivets. So you might pop 30, remove 10, deburr, replace, ect to show evidence that you are capable and competent of 'riveting'.

Next might be to demonstrate you can make a repair by measuring, cutting and drilling a panel. You don't have to make 51% of the craft's panels otherwise.

So the 51% is to demonstrate you are capable of commanding construction and repair to 51% of your craft to have the right to have a Repairman's Certificate for your craft. This is why the quick builds and 2 week build programs are not "cheating".

cheapracer

Well-Known Member
Log Member
Zenith is in the U.S ,in the state of Missouri, located at the airport close to the town called Mexico. Nice area to live.
LOL, well that one got me. Why would you have an airport named "Mexico" for goodness sake's ....

Staggermania

Well-Known Member
HBA Supporter
Well I happen to disagree. The only bugbear to me is that CF is still a little expensive, other than that, a number of simple aluminium builds can be directly replaced with CF sheeting, yes, 'black aluminium'.

Not everybody wants or needs a sleek machine.

They are now adding a teaspoon or 2 of Graphene to Carbon Fiber mixes with spectacular results.

https://www.core77.com/posts/25262/carbon-fiber-and-graphene-two-great-tastes-that-taste-great-and-become-even
I do agree that that “black” aluminum is a possible path to affordable composite aircraft.However, I believe that in order to increase the market for, and thereby decrease the cost, of such an aircraft, sleek will have to be part of the equation.

I am excited by the graphene, but I am wondering if it might be possible in the future to replace the fabrics and long fibers of typical composite construction (layups) with something akin to the short fiber reinforcement used in concrete slabs, let’s say. Something that could be poured in a roto mold, or perhaps even cast?

Himat

Well-Known Member
What inflation adjuster (factor) have you used then?

If your US $398,000 price is right the Cessna is spot on the inflation factor I have used. (M2 monetary inflation.) Since we're talking about the price of a consumer product, I used CPI. M2 is a measure of money supply, and, while it is related to inflation, the actual relationship is convoluted, and doesn't correspond to actual price differences or purchasing power. For price comparisons over time, CPI is the inflation rate to use. https://www.nasdaq.com/articles/confusing-connection-between-m2-and-inflation-2009-12-16 Nice link, I did like the caveat at the end. The interesting thing with the Cessna 172 example is that today price matches the 1981 price if M2 growth is used as the inflation factor and is way of if CPI is used as the inflation factor. Himat Well-Known Member$40,000 in 1981 is equivalent in purchasing power to about $113,182.84 in 2020, a difference of$73,182.84 over 39 years. The 1981 inflation rate was 10.32%
Have a look at my reply in post #95. Could it be that a Cessna 172 is not a consumer item that follow the CPI? Here in Norway the statistical bureau provide indexes for other things than consumer gods, for example building construction have its own price index.

cheapracer

Well-Known Member
Log Member
such an aircraft, sleek will have to be part of the equation.
I 100% disagree, and his is most likely the singular train of thought that has prevented anyone from doing it ... so far.

There is no logical reason why anyone would not want a lighter, faster, more economical plane just because it's made in composite from flat sheet rather than curvaceous moldings.

Victor Bravo

Well-Known Member
Composites can benefit low-speed/high-drag aircraft as much as they can benefit sailplanes and Lancairs. If meeting Part 103 weight (or making a wing light enough to foot launch) is the goal, then carbon and graphene and unobtanium become very useful. Even for "normal" flying machines, as we move toward high fuel prices and look into smaller/cheaper/lighter powerplants, the composites can make things happen easily that are difficult with metal or wood. And although I can't speak from any experience as a manufacturer, our friend Autoreply has admonished us many times that composite parts can be produced very cost/time efficiently when you are set up to do it. It just happened to be that (one particular advantage of) composites first became publicly visible on low drag aircraft like sailplanes and higher efficiency aircraft like the Vari-Eze.

Marc Zeitlin

Exalted Grand Poobah
... And although I can't speak from any experience as a manufacturer, our friend Autoreply has admonished us many times that composite parts can be produced very cost/time efficiently when you are set up to do it...
Do you, or he, have any examples of the cost/time efficient manufacturing of aircraft weight composite parts? I'd love to hear about them or see them. Neither Boeing, Airbus, nor any of the automotive companies have yet been able to do this (obviously they're working on it), nor has ICON, nor other aircraft MFG's. Examples, please.

BoKu

Pundit
HBA Supporter

There is a misconception that 51% means you have to build 51% of the craft, incorrect, it is that you need a 51% build understanding/repair ability of your own craft.

Lets say your craft has 1000 rivets, you don't have to pop 510 rivets yourself, you only have to demonstrate that you have the skillset to repair that area, to prove you are capable of maintaining and repair of those 1000 rivets. So you might pop 30, remove 10, deburr, replace, ect to show evidence that you are capable and competent of 'riveting'.

Next might be to demonstrate you can make a repair by measuring, cutting and drilling a panel. You don't have to make 51% of the craft's panels otherwise.

So the 51% is to demonstrate you are capable of commanding construction and repair to 51% of your craft to have the right to have a Repairman's Certificate for your craft. This is why the quick builds and 2 week build programs are not "cheating".
Can you show me in the regs where that understanding is embodied? Because it doesn't seem to be in the assessment checklist currently in use:

https://www.faa.gov/aircraft/gen_av/ultralights/amateur_built/kits/media/AmBuiltFabAssyCklistFW.pdf

See in specific #7 at the end:

FAA Checklist said:
7. TOTAL BUILDER PERCENTAGE: Add together the two percentage tallies from row 4 Columns C and D blocks only. Total must exceed 50% to be eligible for amateur built status and to meet major portion requirement under 14 CFR, Part 21.191(g) Operating amateur-built aircraft.