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Buying a partial build kit, builder's certificate

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Indytim

Active Member
I've been considering moving from my Mooney to an RV for a while, and I'm looking at various options for how to do the transition. I'm trying to walk a fine line - I want to do as much of my own work as I can, but I'll need to sell my Mooney at some point in the process, to raise cash to finish the build. I don't want to be without a flyable aircraft any longer than I have to, for a bunch of reasons.

One of my goals would be to have a Repairman's Certificate, and to be qualified to do my own maintenance. So I believe that buying a completed RV is out - no way to get a certificate and I wouldn't really understand the build anyway. And it wouldn't be what I want....

I've considered buying a partially built kit, but that seems to raise a bunch of yellow flags. But assuming I find a good quality partial build, how far along could it be, and still allow a Repairman's certificate?

I don't really understand the 51% rule, and how it plays out in practice.
 
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Indytim said:
One of my goals would be to have a builder's certificate, so I can do all my own maintenance. So I believe that buying a completed RV is out - no way to get a certificate
Click to expand...

Building will get you the repairman's cert, which allows you to sign off the annual condition inspection. As a purchaser, you can still conduct maintenance. Not stating opinion about the wisdom of this decision depending on your experience level, just stating fact about what is permitted.
 
Indytim said:
But assuming I find a good quality partial build, how far along could it be, and still allow a builder's certificate?
Click to expand...


First off, the proper name is Repairman's Certificate. In the context of amateur built, the name is probably what causes a lot of the confusion, because it doesn't certify you to repair anything. The only thing the certificate entitles you to do is sign of the annual condition inspection. As already mentioned, anyone can do maint., repairs, or modifications to an RV (including repair of major damage). Whether they built it or not, or whether they have a repairmans cert. or not. Whether they should do any of those things is a totally different discussion.

But to answer your question.....
It depends.....
I have heard of people getting the repairmans certificate for a purchased project that I wouldn't think should qualify, so it depends on who you are working with.
In general, you will need to do enough construction/finish work that will allow you to answer questions to someones satisfaction that you have a detailed enough level of familiarity to properly inspect the airplane.
To be safe, I would recommend that you not look at anything built too far beyond what an normal quick build kit is.
 
rvbuilder2002 said:
First off, the proper name is Repairman's Certificate. In the context of amateur built, the name is probably what causes a lot of the confusion, because it doesn't certify you to repair anything. The only thing the certificate entitles you to do is sign of the annual condition inspection. As already mentioned, anyone can do maint., repairs, or modifications to an RV (including repair of major damage). Whether they built it or not, or whether they have a repairmans cert. or not. Whether they should do any of those things is a totally different discussion.

....
Click to expand...

Thank you for the corrected terminology.

This isn't a simple topic. I need to go do some more research.
 
Just to add to what has already been posted. The 51% rule (officially the Major Portion Rule) has to do with the airworthiness certification of the airplane and absolutely nothing to do with a builder's eligibility for a Repairman's Certificate. You pound 1 rivet and are listed on the certification paperwork as one of the builders then you are "eligible". Note I did not say "qualify" as you still have to demonstrate (although there is wide variation in apparently what this entails) to the FAA that you are qualified to be issued the Certificate. Simply being a builder doesn't automatically bestow this on you.
 
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Scott and Todd both have it right. To qualify for the repairman certificate on an amateur-built aircraft, you must (1) be listed as a builder and (2) show that you are familiar enough with the aircraft to competently perform the condition inspection.
(2) is accomplished by a short interview with a FSDO inspector.
 
Mel said:
Scott and Todd both have it right. To qualify for the repairman certificate on an amateur-built aircraft, you must (1) be listed as a builder and (2) show that you are familiar enough with the aircraft to competently perform the condition inspection.
(2) is accomplished by a short interview with a FSDO inspector.
Click to expand...

This is exactly how it went for me. The FSDO inspector asked me on the phone, "did you build over 50% of it?" and "can you prove it?"

I think the 50%+ was just some number he figured would satisfy (2), but that's what he asked me.
 
Amateur-Built Fabrication and Assembly Checklist (2009) Job Aid

Ok, I've been doing a bunch of reading on this topic, trying to get to the heart of the matter. I'm fascinated by the mathematical logic contained in the below-reference Fab/Assy Job Aid pamphlet. (I'll call it ABFAC)

If I understand things correctly, an FAA inspector should use its guidance to determine if the builder met the 51% requirement. Ok. But...

In the ABFAC, there are various tables of operations, e.g.
W1 Fabricate Wing Spars
W2 Assemble Wing Spars to Wing

Each operation is allocated a score, which reflects the percent of effort the builder invested, vs the time allocated by the manufacturer.

The theory is that the examiner would scrutinize the builder's logs and photos, and assign a score to each operation. Then, total the scores and voila! the resultant score indicates the percentage of effort that the builder invested, compared to that of the manufacture.

But.... there is no accounting for the actual amount of time each operation takes. Which means that I could spend 2000 hours fabricating some particularly pernicious component (canopies come to mind, as worthy examples), but I could only get a max of 1 point for that ordeal. Ok, maybe the operation is three tasks, e.g. form/trim/sand or whatever, so I get 3 big points.

Conversely, I could have a bunch of tiny operations that take, say 1 hour each, and I could get 1 point for each of them?

How does the total represent % of effort, if each operation does not take into account the total time of that respective operation?

There is some mathematical law being violated here. Or am I just unused to government math?

What am I missing?

The pamphlet in question is this one: Amateur-Built Fabrication and Assembly Checklist (2009) Job Aid (https://www.faa.gov/aircraft/gen_av/ultralights/amateur_built/kits/media/Am_Blt_Chklist_Job_Aid.pdf)
 
John Courte said:
This is exactly how it went for me. The FSDO inspector asked me on the phone, "did you build over 50% of it?" and "can you prove it?"

I think the 50%+ was just some number he figured would satisfy (2), but that's what he asked me.
Click to expand...

So it's kind of like one's tax return: try to get it right, and be able to cough up the data if you ever get audited?
 
Indytim said:
Ok, I've been doing a bunch of reading on this topic, trying to get to the heart of the matter. I'm fascinated by the mathematical logic contained in the below-reference Fab/Assy Job Aid pamphlet. (I'll call it ABFAC)

If I understand things correctly, an FAA inspector should use its guidance to determine if the builder met the 51% requirement. Ok. But...

In the ABFAC, there are various tables of operations, e.g.
W1 Fabricate Wing Spars
W2 Assemble Wing Spars to Wing

Each operation is allocated a score, which reflects the percent of effort the builder invested, vs the time allocated by the manufacturer.

The theory is that the examiner would scrutinize the builder's logs and photos, and assign a score to each operation. Then, total the scores and voila! the resultant score indicates the percentage of effort that the builder invested, compared to that of the manufacture.

But.... there is no accounting for the actual amount of time each operation takes. Which means that I could spend 2000 hours fabricating some particularly pernicious component (canopies come to mind, as worthy examples), but I could only get a max of 1 point for that ordeal. Ok, maybe the operation is three tasks, e.g. form/trim/sand or whatever, so I get 3 big points.

Conversely, I could have a bunch of tiny operations that take, say 1 hour each, and I could get 1 point for each of them?

How does the total represent % of effort, if each operation does not take into account the total time of that respective operation?

There is some mathematical law being violated here. Or am I just unused to government math?

What am I missing?

The pamphlet in question is this one: Amateur-Built Fabrication and Assembly Checklist (2009) Job Aid (https://www.faa.gov/aircraft/gen_av/ultralights/amateur_built/kits/media/Am_Blt_Chklist_Job_Aid.pdf)
Click to expand...

For an RV (or any kit on the NKET approved list) you're over-thinking this. It's an approved kit so the math has been done for you by Van's. The only rub, as I see it, is making sure on a partial kit the previous builder didn't violate the allowed commercial assistance part. Chances are it's a non issue.

For a partial kit, I'd be concerned with build quality 1st, and documentation 2nd. If either is suspect, I'd walk away and find another project.
 
Indytim said:
But.... there is no accounting for the actual amount of time each operation takes. Which means that I could spend 2000 hours fabricating some particularly pernicious component (canopies come to mind, as worthy examples), but I could only get a max of 1 point for that ordeal. Ok, maybe the operation is three tasks, e.g. form/trim/sand or whatever, so I get 3 big points.

Conversely, I could have a bunch of tiny operations that take, say 1 hour each, and I could get 1 point for each of them?

How does the total represent % of effort, if each operation does not take into account the total time of that respective operation?

There is some mathematical law being violated here. Or am I just unused to government math?

What am I missing?

The pamphlet in question is this one: Amateur-Built Fabrication and Assembly Checklist (2009) Job Aid (https://www.faa.gov/aircraft/gen_av/ultralights/amateur_built/kits/media/Am_Blt_Chklist_Job_Aid.pdf)
Click to expand...

Since you asked, time to complete a task has no bearing on the math. The FAA determines how much credit the builder gets for a given task based more on what is required to complete the task which generally seems to be attributed to how finished a part is or how much of a given component is completed by the factory before they ship it. For example do you unwrap a part and simply bolt it on, or did you have to finish some aspects of it before it could be installed, or did you have to fabricate the part out of raw material based upon directions in the manual? I have no clue as to how they actually come up with the percentages a given level of effort earns (I'm guessing dart board). But truth be told unless you're building something plans built or using commercial assistance this is really a non-issue as the FAA as has already determined that the kit has at least 51% or more of the work required to complete it left for the builder to do.
 
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John Courte said:
This is exactly how it went for me. The FSDO inspector asked me on the phone, "did you build over 50% of it?" and "can you prove it?"

I think the 50%+ was just some number he figured would satisfy (2), but that's what he asked me.
Click to expand...

I guess our inspectors are more involved. To get my repairman cert. ( I did the entire build alone.) the FSDO inspector came to my hangar and asked me questions and explained what to do during an annual inspection for an hour or so.

He asked questions like: How are the fuel vent lines routed and how would you make sure they are not blocked? Obviously if you built the thing those are easy questions and you know the answers if you had somebody else built it you might or might not. He never even looked at my build logs and I had such a nice picture book ready.... .

Overall it was a quite positive experience as I certainly learned a couple of things e.g. He suggested to put the plane sidewards in the hangar for the inspection as your brain is more likely to find faults if things don't look like usual. Something I wouldn't have thought about.

Only thing I don't understand is why the FSDO has the resources to drive to my airport for this for free but I have to pay a DAR to get my exp. cert. ... . I guess I shouldn't complain as then they will start charging for that too.

Oliver
P.s. I did feel bad for the part 135 operators at our airport. Apparently the FSDO inspector took that opportunity for giving them a ramp check.... .
 
Auburntsts said:
I have no clue as to how they actually come up with the percentages a given level of effort earns (I'm guessing dart board).
Click to expand...

What has to be kept in mind is the context that makes us eligible to build an airplane and then get an airworthiness certificate for it.
In the simplest terms, the airplane has to have been built for a persons education and recreation.
So everything related to the evaluation process is based off of that requirement. The actual check list was developed based on that requirement, in an attempt to try and separate airplanes built meeting that requirement, from the ones built professionally.
 
Not necessarily.......

Auburntsts said:
But truth be told unless you're building something plans built or using commercial assistance this is really a non-issue as the FAA as has already determined that the kit has at least 51% or more of the work required to complete it left for the builder to do.
Click to expand...

There are quite a few kits out there that have not been evaluated by the FAA. If your particular kit is not on the current approved kit list, you must use the form contained within AC 20-27 to show compliance with the "Major Portion" rule.
 
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