51% rule?

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Scarecrow56

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Hello again. Just let me start off by saying that you guys are great and this is a great forum!:ban: Really no wise guys or drama to really speak of. A breath of fresh air in todays social media.

That being said, what exactly is the 51% rule or rather how does it work. I think I know but I wanna get clarification. Lemme try this, You can do your own inspections and work on your own airplane IF YOU built it but if you buy it already built and YOU DIDNT BUILD it you cant unless you take a course? How'd I do? Thanks again!
 

radfordc

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Much more complicated than that. Rules are different for experimental-amature built, exp-light sport, and special-light.
- you can do all maintenance on any experimental aircraft whether you built it or not.
- you can do annual condition inspection on exp-ab only if you have a repairman certificate, you get that for building according to the 51percent rule
- you can inspect any exp-lsa for which you have a repairman certificate, which you can get by taking a two-day school
 

Toobuilder

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...you can do annual condition inspection on exp-ab onlyif you have a repairman certificate, you get that for building according to the 51percent rule...
Bold added...

A "non builder" who is also an A&P can also perform and sign off the Condition Inspection for an E-AB.
 

Wanttaja

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Hello again. Just let me start off by saying that you guys are great and this is a great forum!:ban: Really no wise guys or drama to really speak of. A breath of fresh air in todays social media.

That being said, what exactly is the 51% rule or rather how does it work. I think I know but I wanna get clarification. Lemme try this, You can do your own inspections and work on your own airplane IF YOU built it but if you buy it already built and YOU DIDNT BUILD it you cant unless you take a course? How'd I do? Thanks again!
You're mixing two different kinds of aircraft certification.

Let's start with the traditional "homebuilt" category, Special airworthiness under the Experimental Amateur-Built (EAB) category. To qualify as an EAB, the majority of the construction has to be performed for education or recreation. This "majority" is deemed by the FAA as "51%". Their interpretation of "majority of the construction" has softened over the years; the FAA now deems that 51% of the TASKS (not building hours) must have been performed for recreation or education. Instead of having to build over half the ribs, for instance, building ribs is considered a "task" and all you might have do to is built one.

The makers of aircraft kits have the FAA assess their product to verify that it qualifies under the "51% Rule." If so, the Designated Airworthiness Representative (DAR) doesn't have to assess the basic kit to determine whether it qualifies. Being on the FAA's list is NOT required, especially for plans-built designs for which kits aren't available. Being on the 51% list isn't an automatic pass; if the "builder" hired someone to build portions or the entirety of the aircraft, this may cause the DAR to reject it. Some aspects, such as avionics, do not affect the amateur-built assessment.

The builder of an EAB aircraft is not governed by the plans or kit instructions. He or she may perform any modifications they wish. Practically speaking, there are no limitations on the aircraft equipment or performance.

When the plane is completed, anyone can perform maintenance on it or modify it as they desire. However, once a year, the plane must undergo an inspection to verify that the plane is in a safe condition for flight. This is not, technically, an "annual inspection" though most of us tend to use that term (an official "annual inspection" verifies that the aircraft complies with its Type Certificate, and EAB aircraft don't have one). The inspection can be performed by a licensed A&P mechanic (an IA is not required) or the holder for the Repairman Certificate for that specific aircraft. The "Majority Builder" of the aircraft can apply for the Repairman Certificate. Only one is issued to each EAB aircraft, and it is not transferable.

Let's contrast this to another Special Airworthiness category, Experimental Light Sport Aircraft (ELSA). There is no 51% rule for ELSA...the manufacturer can sell kits in any level of completion, even completely built. However, prior to selling the kit, the manufacturer must take the design through a complete certification in the Special Light Sport Aircraft (SLSA) category. This process uses a consensus standard developed by the industry itself rather than the ordinary FAA certification regulations. Once the aircraft has passed the requirements of the consensus standard, it can be sold either as ready-to-fly (Special Light Sport Aircraft) or as an ELSA with any degree of builder completion required. ELSA/SLSA aircraft must comply with the FAA's "Light Sport Aircraft" definition in 14CFR Part 1, which limits the weight, capability, and performance of the aircraft.

The builder of an ELSA kit *must* strictly comply with the building instructions provided by the kit maker. He or she cannot deviate...if the instructions say, "Install an O-200A engine" the builder cannot use an O-200C engine instead. Similarly, the builder cannot just install whatever radios and other equipment that they want.

When completed, a DAR examines the aircraft to verify that it was build in accordance to the manufacturer instructions and configuration. But once the DAR has granted the aircraft its ELSA airworthiness certificate, the controls are off...the owner can immediately replace that O-200A with an O-200C, if they desire. However, the aircraft must still meet the 14CFR Part 1 Light Sport definition...the gross weight is still limited, the stall speed cannot exceed the requirements, etc.

Like the EAB aircraft, anyone can maintain or modify an ELSA. However, the FAA does NOT issue Repairman Certificate for the individual aircraft. Anyone can take a course for Repairman Certificate Light Sport Inspector. This is a short (16 hour) course that covers what it necessary to verify the safe condition of an Experimental Light Sport Aircraft. Once a person has successfully completed the course, he or she may perform the annual Condition Inspection for any ELSA *that they own*.

Another Repairman Certificate is available...Light Sport Maintenance. This is a longer course (~200 hours, IIRC) that, when completed, allows the certificate holder to perform the annual Condition Inspection for any Experimental Light Sport and Special Light Sport Aircraft, regardless of ownership. This is the equivalent of the A&P/IA license, but is only applicable to the Light Sport world.

So to summarize:

Experimental Amateur-Built. More freedom during construction, aircraft can be much more capable, but more builder work generally required. Only the original builder usually qualifies for the Repairman Certificate. Otherwise an A&P mechanic is required for the annual Condition Inspection. Anyone can perform maintenance or upgrades to the aircraft.

Experimental Light Sport: No freedom during construction, aircraft have limited performance. An owner can take a 16-hour course that will permit him or her to perform the Condition Inspection. Otherwise, an A&P mechanic or a person with a Repairman Certificate - Light Sport Maintenance is required. Anyone can perform maintenance or upgrades to the aircraft.

Ron Wanttaja
 

BJC

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Is it correct that an E-AB that meets the criteria for Light Sport Aircraft may be flown by a pilot with a Sport Pilot license and maintained and annually certified as in condition for safe flight just as any other E-AB?


BJC
 

Wanttaja

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Is it correct that an E-AB that meets the criteria for Light Sport Aircraft may be flown by a pilot with a Sport Pilot license and maintained and annually certified as in condition for safe flight just as any other E-AB?
Yes.

I like the Light Sport concept, but one of the dumbest things the FAA did was to use the same term ("Light Sport") in two different ways.

They created new certification categories, Special Light Sport Aircraft and Experimental Light Sport Aircraft, and at the same time defined a term, "Light Sport" in 14CFR Part 1, "Definitions and Abbreviations".

The definition in Part 1 basically defines what aircraft a Sport Pilot can fly. The certification categories describe the process for certifying NEW aircraft that meet those criteria, but are NOT the only aircraft that can be flown by Sport Pilots.

As BJC says, if the aircraft meets the Light Sport definition in Part 1, a Sport Pilot can fly it...regardless of the airplane's certification category. It can be an SLSA/ELSA, an EAB, Standard Category, Limited, Normal, Aerobatic, WHATever.


What it doesn't do is affect the actual certification of the aircraft in question. Standard Category aircraft that meet the Part 1 definition can be flown by Sport Pilots, but they must still be equipped, maintained, and inspected as Standard Category aircraft. A person with a Light Sport Maintenance Repairman Certificate cannot perform the Annual Inspection of a Standard Category aircraft; it still requires an A&P/IA. Ditto the EAB, its condition inspection cannot be performed by someone with a Light Sport Inspector Repairman Certificate, it must be done by either a person possessing the RC for THAT aircraft, or an A&P.

Ron Wanttaja
 

jedi

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Is it correct that an E-AB that meets the criteria for Light Sport Aircraft may be flown by a pilot with a Sport Pilot license and maintained and annually certified as in condition for safe flight just as any other E-AB?


BJC
Yes.

Now for the ifs, ands and buts. A "Sport Pilot License" does not exist, it is a "Sport Pilot Certificate". Do not confuse "Light Sport Pilot" with "Light Sport Aircraft", one is a person and the other is a machine.

A light sport pilot can be qualified to fly any airworthy light sport aircraft he/she is qualified in. What determines if the aircraft is airworthy? A current airworthiness certificate, a valid condition inspection and a thorough pre-flight inspection including a review of applicable AD* notes. What determines sport pilot qualifications. Many things including endorsements and currency requirements.

Endorsements may be for Vh speeds greater than or less than 87 kts. Land or sea ratings, airplane, WSC (Weight Shift Control), rotorcraft or PPC (Powered Para-Chute) clasifications, etc. (tail wheel for example).

Currency requirements include FR (a current Flight Review), 90 day currency (three takeoffs and landings required to carry a passenger), etc. (current drivers license).

All of the above is very clearly covered in CFR 14 Part 61 and Part 91. Welcome to the "Realm of Flight" according to the USA FAA.

* Wikipedia - An airworthiness directive (commonly abbreviated as AD) is a notification to owners and operators of certified aircraft that a known safety deficiency with a particular model of aircraft, engine, avionics or other system exists and must be corrected.
 
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Dana

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Now for the ifs, ands and buts. A "Sport Pilot License" does not exist, it is a "Sport Pilot Certificate". Do not confuse "Light Sport Pilot" with "Light Sport Aircraft", one is a person and the other is a machine.

A light sport pilot can be qualified to fly any airworthy light sport aircraft he/she is qualified in...
Actually it's "Light-Sport Aircraft", but just "Sport Pilot", not "Light Sport Pilot". A Sport Pilot can fly a Light-Sport Aircraft (which is a certification category) or a standard or experimental aircraft which otherwise meets the Light-Sport definition.

Still looking for a way to register a deregistered airplane with no builder's logs. No repairman's cert required.
Deregistered doesn't matter, as long as you have the airworthiness certificate. If the AWC was turned in and the aircraft reported destroyed or disassembled, you're out of luck.
 

pfarber

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a DAR examines the aircraft to verify that it was build in accordance to the manufacturer instructions and configuration.
No. No. No. No. The DAR verifies that the BUILD METHODS are IAW FAA standards.

A DAR doesn't need to know ANYTHING about the aircraft design. But if it uses turnbuckles, they must be safety wired. If a bolt has 5 washers instead of the max 3 allowed, missing cotter pins, is the weight and balance correct etc etc etc.

In most cases its very good double check to have a DAR that knows about your specific AC, but any DAR can sign off on any E-AB.
 

Wanttaja

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Wanttaja said:
a DAR examines the aircraft to verify that it was build in accordance to the manufacturer instructions and configuration.
No. No. No. No. The DAR verifies that the BUILD METHODS are IAW FAA standards.
Not on an ELSA, which is what I was addressing. An ELSA must be built in strict accordance to the manufacturer's instructions, and the DAR is the only one who can verify that.

The rules are different for Experimental Amateur-Built aircraft, as I said in my original post.

Ron Wanttaja
 
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Fireflyer228

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You're mixing two different kinds of aircraft certification.

Let's start with the traditional "homebuilt" category, Special airworthiness under the Experimental Amateur-Built (EAB) category. To qualify as an EAB, the majority of the construction has to be performed for education or recreation. This "majority" is deemed by the FAA as "51%". Their interpretation of "majority of the construction" has softened over the years; the FAA now deems that 51% of the TASKS (not building hours) must have been performed for recreation or education. Instead of having to build over half the ribs, for instance, building ribs is considered a "task" and all you might have do to is built one.

The makers of aircraft kits have the FAA assess their product to verify that it qualifies under the "51% Rule." If so, the Designated Airworthiness Representative (DAR) doesn't have to assess the basic kit to determine whether it qualifies. Being on the FAA's list is NOT required, especially for plans-built designs for which kits aren't available. Being on the 51% list isn't an automatic pass; if the "builder" hired someone to build portions or the entirety of the aircraft, this may cause the DAR to reject it. Some aspects, such as avionics, do not affect the amateur-built assessment.

The builder of an EAB aircraft is not governed by the plans or kit instructions. He or she may perform any modifications they wish. Practically speaking, there are no limitations on the aircraft equipment or performance.

When the plane is completed, anyone can perform maintenance on it or modify it as they desire. However, once a year, the plane must undergo an inspection to verify that the plane is in a safe condition for flight. This is not, technically, an "annual inspection" though most of us tend to use that term (an official "annual inspection" verifies that the aircraft complies with its Type Certificate, and EAB aircraft don't have one). The inspection can be performed by a licensed A&P mechanic (an IA is not required) or the holder for the Repairman Certificate for that specific aircraft. The "Majority Builder" of the aircraft can apply for the Repairman Certificate. Only one is issued to each EAB aircraft, and it is not transferable.

So to summarize:

Experimental Amateur-Built. More freedom during construction, aircraft can be much more capable, but more builder work generally required. Only the original builder usually qualifies for the Repairman Certificate. Otherwise an A&P mechanic is required for the annual Condition Inspection. Anyone can perform maintenance or upgrades to the aircraft.



Ron Wanttaja
Ron,

Great post and also the comments of others. I snipped out the E-AB portions. "Only one repariman certificate is issued to an E-AB aircraft"? Even if another builder and has rebuilt more than the previous owner and documented it? I thought the original builder would still be on the 8130-12, ELIGIBILITY STATEMENT AMATEUR-BUILT AIRCRAFT, but a new form would be submitted. Using the FAA percent per task / build points sheet.

AC 20-27G
17. Becoming a Repairman of Your Amateur-Built Aircraft. You can get a repairman certificate under certain circumstances. However, the only privilege this certificate gives you under 14 CFR § 65.104, Repairman certificate—experimental aircraft builder—Eligibility, privileges and limitations, is to do the annual condition inspection. The certificate will be valid only for a specific person and a specific aircraft. The privileges and limitations in part 65, Certification: Airmen Other Than Flight Crewmembers, § 65.103, Repairman certificate: Privileges and limitations, do not apply to becoming this type of repairman (experimental aircraft builder). To get a certificate, apply to your local FAA office. See Appendix 14 to this AC and AC 65-23, Certification of Repairmen (Experimental Aircraft Builders), for additional application information. You can get a certificate if you are— page 30
continued next page:
a. The primary builder of your aircraft, even as the second builder, and can satisfactorily prove to us that you can determine whether the aircraft is in a condition for safe operation.
b. One of the builders of an amateur-built aircraft registered in a corporation’s name. The applicant should prove through use of the builder’s log that they can determine whether the aircraft is in a condition for safe operation.

AC 20-27 Appendix 8, page 8-1
I had found a list of tasks that had a weight percentage. ie. building wing - 12%. Appendix 8 is a form showing more than 50% of an E-AB aircraft was documented and where the 'primary builder' spent their time. If I completely rebuilt every nut, bolt and rivet on the aircraft, I would be the 'primary builder'.

AC 65-23 listed in the FAA copied text above.
4.ELIGIBILITY. An individual desiring to be certificated as a repairman is required to:
a.Complete an application for a repairman certificate (experimental aircraft builder) at the time of original certification of the aircraft along with FAA Form 8130-12 attesting to building more than 50 percent of the aircraft, which must be notarized.
b.Be a U.S. citizen, or an individual of a foreign country, who has been admitted for permanent residence in the United States.
c.Be 18 years of age or older and the primary builder of the aircraft. For example, when a school, club, or partnership builds an aircraft, only one individual will be considered for a repairman certificate for each aircraft built, such as the class instructor or designated project leader. This individual is considered the primary builder.
d.Demonstrate to the certificating FAA inspector the ability to perform condition inspections and to determine whether the subject aircraft is in a condition for safe operation.
e.Present satisfactory evidence of building the aircraft such as a construction logbook, pictures, or drawings to be eligible for the certificate.



If I were to rebuild an aircraft with an existing Airworthiness Certificate, I could document every part built, every action taken to re-file 'Second builder'. Or if the Second Builder clause of part a. is not acceptable then I could do anything to the aircraft. Upto and including rebuild the entire E-AB craft, but I would need an A&P or AI to verify airworthiness again, or an 'E-AB not a real annual', or a safety check. What does that necessary inspection turn into? what if it's a new engine? IP change, new gear, new W&B,... What does that inspect become for an aircraft currently registered and with it's white ticket? No DAR necessary since the A/C has a white ticket already? If you turn in the Airworthiness Certificate back to the FAA, how do you reapply for a new one? Then can you become the 'primary builder' with documentation?

Thanks for your time all. I'm not trying to be difficult, although it may sound like it. I'm trying to thoroughly understand the rules I need to work to. It almost sounds easier to build a replica of the aircraft from no plans (because the FAA doesn't care about that) and get that signed of by a DAR then apply for a Repairman Certificate. Or rebuild the initial aircraft and in the years of rebuilding get my A&P which I want to get anyhow.

Thanks,
Kenneth
 

Dana

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No. You have to "Complete an application for a repairman certificate (experimental aircraft builder) at the time of original certification of the aircraft." If you're rebuilding an already certified aircraft, that window is closed. Even if you rebuild the entire aircraft, there is no new FAA inspection required, just a current condition inspection, the old airworthiness certificate is still valid.
 

Turd Ferguson

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If I were to rebuild an aircraft with an existing Airworthiness Certificate, I could document every part built, every action taken to re-file 'Second builder'. Or if the Second Builder clause of part a. is not acceptable then I could do anything to the aircraft. Upto and including rebuild the entire E-AB craft, but I would need an A&P or AI to verify airworthiness again, or an 'E-AB not a real annual', or a safety check. What does that necessary inspection turn into? what if it's a new engine? IP change, new gear, new W&B,... What does that inspect become for an aircraft currently registered and with it's white ticket? No DAR necessary since the A/C has a white ticket already? If you turn in the Airworthiness Certificate back to the FAA, how do you reapply for a new one? Then can you become the 'primary builder' with documentation?
Uh, no. The FAA doesn't recognize rebuilding, or restoring or refinishing already fabricated components as "fabrication and assembly for education or recreation."

Rebuilding that doesn't involve fabrication will likely cause you to come up short on the major portion rule required for registering an aircraft as amateur built aircraft so it's better to not forfeit any of the existing paperwork. You can certainly rebuild the aircraft and the only thing it needs is a condition inspection at some point in the preceding 12 months to be legal to fly.

You're getting there. Just keep reading. Don't try to shortcut the regulations. A homebuilt airplane does not meet any standard for airworthiness so nobody pronounces it "airworthy" ever. Nobody can make you put a "new engine" or "new gear" on a homebuilt. Not sure what you are referencing with "white ticket"
 

kent Ashton

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Still looking for a way to register a deregistered airplane with no builder's logs. No repairman's cert required.
If the aircraft ever had an AC and you know the former N-number, you can query Oklahoma City for a copy of the old AC. Then, with proper bills of sale that prove chain-of-title from the last FAA-recognized owner to you, you can reregister the airplane in your name and request reissue of the AC.
 

Fireflyer228

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Uh, no. The FAA doesn't recognize rebuilding, or restoring or refinishing already fabricated components as "fabrication and assembly for education or recreation."

Rebuilding that doesn't involve fabrication will likely cause you to come up short on the major portion rule required for registering an aircraft as amateur built aircraft so it's better to not forfeit any of the existing paperwork. You can certainly rebuild the aircraft and the only thing it needs is a condition inspection at some point in the preceding 12 months to be legal to fly.

You're getting there. Just keep reading. Don't try to shortcut the regulations. A homebuilt airplane does not meet any standard for airworthiness so nobody pronounces it "airworthy" ever. Nobody can make you put a "new engine" or "new gear" on a homebuilt. Not sure what you are referencing with "white ticket"
I have heard the Airworthiness Certificate referred to as the 'white ticket'.

Added note. Airworthiness Cert is white for Certified aircraft, I just noticed my E-AB Special Airworthiness Certificate is pink. Is this normal?
 
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