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Miserable quality loves company.

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Captain Avgas

Well Known Member
Well, in reality the proverb is actually: "Misery loves company". But on VansAirforce it might well be interpreted as: "Miserable quality loves company".

In other words people who have built to a low standard tend to encourage other builders to do the same.

A recent thread on VansAirforce asking for advice on whether a damaged rudder skin should be repaired or replaced attracted a lot of disparate suggestions and was revealing. This was the thread https://vansairforce.net/community/showthread.php?t=195668

I have started up this new thread because I believe that the time is well overdue for a serious discussion about attitudes to quality control (or lack thereof) in the Experimental Category.

In the end the quality of aircraft being fabricated in the Experimental Category is largely unregulated and virtually entirely dependent on the personality of the builder. It is therefore not surprising that a very broad spectrum of builder personalities tends to result in a very broad spectrum of build qualities. Toss in the fact that many builders are not even that interested in building and the scene is set for a lot of very poorly constructed aircraft.

I have been a technical counsellor for the Sports Aircraft Association of Australia for the best part of two decades and was an aircraft judge for 7 years straight. I have closely inspected literally hundreds of Experimental aircraft. Some of them were works of art...but many off them were truly appalling.

I constantly hear builders say: "I'm building to go, not to show". I tend to interpret that as the builder saying he is not building to the best of his abilities. Another common one is: "It's not a show plane but it's airworthy". But in my experience a lot of them are not airworthy at all.

I believe that when we post on VansAirforce we have a duty to encourage excellence as a standard....not to promote the concept that close enough is good enough. I believe that the safety of the builder and his family and the future of the Experimental Category at large will be better served by this approach.

I'll finish with a quote by Michelangelo: "The greatest danger for most of us is not that our aim is too high and we miss it; but that it is too low and we reach it".

He was a pretty smart guy that Michelangelo.
 
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I've seen things that bothered me on aircraft, both certified and experimental. What might be very interesting is to hear about the kinds of things you have seen, kind of like when Vic shares his findings.

One of the most common for me is firewall penetrations that have little or no actual fire resistance. Or when you can see that they are not sealed at all.
 
Define Airworthy

While VAF is a great community, it's not the written airworthiness standard. For that there is the Van's Builder's manual, section 5 has a lot of good info. Next there's AC 43.13 and a couple quick reference guides developed from that. Also Van's builder support is another authority of airworthiness.

For everything we do on our planes, we need to be able to reference everything back to one of these standards. "Good enough" is only good enough if the AC43.13 or Van's says its good enough.

I'm not just concerned about low quality work either, some expect unrealistic perfection as the minimum standard. My plane won't be a show plane either, and I've certainly made mistakes. However, I can reference everything back to the plans, AC43.13 or an email with builder support (and I keep all those emails).
 
In your example post about the rudder skin, VANS authorized and gave instructions on how to repair the part. In that same post you implied that builders who make repairs are sub standard.

Exactly what standards do you recommend? You obviously don't agree with the kit manufacturer's recommendations.

There is nothing wrong with a builder saying "It's not a show plane but it's airworthy" An airworthy plane has a defined standard, inspection and sign off. A show plane usually has a multi thousand dollar paint job.

I made the same mistake as rudder skin guy, but on the VS skin to rib. I repaired it with two rivets on either side of the mistake hole, as was recommended. I must not have any standards...
 
High quality/perfection should always be the goal, but in the real world mistakes are made. In that case a standard repair or repair developed by the manufacturer is absolutely acceptable. I'm not a big fan of replacing riveted parts unless it's really necessary, no matter how good you are when you drill out rivets the holes will be enlarged by the riveting process and things aren't getting "better" at this point even though it may look better.

We had an old saying the aircraft manufacturing world, the plane doesn't leave until the paperwork weighs as much as the plane, that's because all the engineering repair documents have to be completed for all the repairs made during the build process. There's a whole engineering dept that does nothing but develop repairs for new planes before they even leave the factory!
 
I think one of the problems we have is that experimental airplanes have become a cheap substitute for certified airplanes.

Experimental airplanes by name and intend at least in the US were intended for people to experiment and learn. That means breaking the norm and taking the risks you want to take rather than the risks some regulation, guide book, standard allows you to take. Try to defy physics and kill yourself if you want to. It's allowed. Even though I wasn't born in the US I find having this freedom is a very American thing. A freedom I greatly appreciate now living here sometimes being surprised that nobody has taken it away from me yet.

Now that worked well when people approached this with a truly experimental mindset and were aware and willing to educate themselves and take the risks knowingly.

The problem today is that a large number of experimental airplanes are not build because people want to experiment and learn but because it is the cheapest way to get a high performance airplane. As the original builder might or might not understand the ramifications of all those decisions made during a build the odds are when the airplane gets sold the buyer won't. A pre buy can catch many things but not everything.

So what to do?

I don't know.

For the buyers some standard would make sure that whatever they buy has at least some acceptable quality. But we tried standards with certified airplanes and they made them unafordable.

On the other hand if you look at overall statistics experimental airplanes are only marginally more dangerous then your Cessna or Piper. With very little deaths due to structural issues which is what most of those posts are about. Never heard of an RV breaking apart in mid air because of a crack in the skin. That would argue that whatever sloppy/unorthodox/misinformed build practices you see don't lead to deaths at the scale some might expect. So don't fix something that isn't broken.


Oliver
 
Removing freedom to fail is removing freedom to succeed at the same time. RV related, I will defend this concept as creating opportunities for those with the drive and skills to build an airplane beyond what they could afford to purchase and maintain. Even if learning those skills are part of that accomplishment.

Anyone who thinks it is cheap to build their own plane would not have measured the straight value of their time. Education is not free, even if self taught. Time, materials, failures are part of that. At least VAF has members with a wide (and deep) range of skills/experiences to be imparted to those listening.

Along these lines, the OP maybe interpreted as promoting a mind set of quality, but primarily safety to the process.

My personal reflection of quality is best exemplified by this quote: "as we strive for perfection, we oft mar what is well" (poorly quoted Shakespeare I think?) This, as Walt has so clearly pointed out.
 
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The buggered dimple thing is a lousy example. As noted in that thread, there is plenty of room for opinion, opinions vary, and no one is wrong.

I'm not worried about Ray and his rudder. He recognized an error and took positive steps toward a good decision. It's like the checkride where the examiner is not concerned with the applicant's mistake. What he wants to see is that the applicant recognized his mistake and calmly corrected it.

The folks who are inspecting RVs for a living, usually on behalf of second owner non-builders, are in fact finding a lot of errors and poor craftsmanship. These are not "replace or replace" debates like the rudder skin. A lot of 'em are outright crazy s###, and in every case, someone found it acceptable.

Half the EAB fleet is below average. Every builder gets to pick his half.
 
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I should preface by saying that I'm not a builder, and my interest in Experimental Aviation extends only to the flying part, and maybe some maintenance items. ZERO interest in building a plane that I'm going to fly myself or people that I care about.

One of the things that has convinced me that I am NOT an airplane builder is the kind-of Dogpatch approach that I occasionally see proposed or endorsed on some homebuilt forums. As a long-time pilot in the certified world, I see some things on experimental forums that are eye-opening to me, and at least a little bit scary. I don't know if those kinds of issues translate to a higher accident rate in the Experimental world, but I would think that some attitudinal aspects of home-building do contribute. Regardless...my personal approach to Experimental aviation relies heavily on my A&P and less on internet advice.
 
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Looking at your title, it is really sad that if a mistake is made and repaired according the manufacturers guidance, someone will pop up and call that persons work "Miserable Quality"

While I understand your intent, IMHO this bashing goes too far in pushing everyone to your unique standard. Degrading someone's work product should really be reserved for far more serious infraction of your "quality code."

I also have inspected several planes and seen some scarry stuff and feel that many builder standards should be higher. But using the Gold Lindy checklist to determine quality goes too far. Blowing the edge distance on the H stab attach or rear spar is not anywhere near the same neighborhood as the rudder skin example you referenced.

Larry
 
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i completeley disagree. who decides what is mysery and what is excellence? who is the censoring authority?

this is the internet after all. there's a lot of great Information and advise, and there's a lot of nonsense. people building aircrafts are usually grown man. everybody has to judge for himself how useful a given Informationen is. if you aim to build a perfect plane... great. if you want an airworthy plane... that's fine too.

this thread leads to nothing.
 
Ain't nobody building perfect airplanes ... but I like to operate with "no shame left behind" ...
 
please don't be miserable, don't worry, be happy, we're not here for a long time, but a good time, and the sun don't shine every day :):):)
 
Airworthy means airworthy, not beautiful. We've all seen the Lindy award winners with polished exhaust tubes, etc. It doesn't mean anything other than the owner is probably OCD. Certified planes aren't perfect. I used to own a '94 A36 Bonanza. When I put it up for sale, one of the prospective buyers found an area where the boot cowl met the firewall where Cherry rivets had been installed. I was surprised by this and couldn't explain it. Of course, he thought I was hiding something so he walked. I had Tulsair research this and lo and behold the factory had installed them as a part of a repair before the plane was sold as new. Airworthy? Yep. Pretty? No...Repairs are fine as long as they meet the basic requirements set forth by either the manufacturer or AC43.

I've also seen some amazing things on airliners, as have most of us. The patch with what seems like 2000 rivets just over the passenger entrance? How many times have we seen that?
 
I’m also not a builder but a “buyer and flyer.” However I too have my concerns with the quality I’ve seen on some experimental aircraft. And for that matter many older certificated aircraft too!

As with all human endeavors “one’s attitude, values and character” often dictates outcomes. Building, buying, owning and maintaining any complex piece of machinery requires attention to detail beyond what seems to be “average” for most of us.

One of the main reasons for my initial consideration of an experimental aircraft was my observation of the affordable typical older certificated aircraft for sale that had had several owners, annuals, upgrades, and repairs. Many of theses aircraft had “bird nest panels”, “oily concrete areas under the engine cowling”, and just nasty engine compartments with old wiring hanging around, etc. Yet, these aircraft were being signed off by an A&P/IA as air worthy. For the money I was willing to spend the experimental market appeared to offer better bang for the buck with no less flying risk - assuming I found something decent.

The biggest mistake I made buying the RV I did was not getting my “prebuy” done by an RV expert - I used a local A&P/IA. Had I used a RV expert I think the build quality issues later discovered wouldn’t have been the surprise they were. That is NOT to say that I didn’t make a good purchase choice because I did! It’s just that with any aircraft purchase there are going to be surprises and being “for warned” is much better than discovery later. The big problem once issues are discovered is what next! That’s where attitude, values and character enter into the equation.

Safety is paramount! If you’re going to fly over or carry anyone besides yourself then you owe it to your family, friends, future aircraft owners, and your fellow human being to build and maintain the safest aircraft you can. Unfortunately none of us know when, where and how serious the next inflight situation will be. We can only hedge our bets by owning the best built and maintained aircraft we can! Strive for excellence and pray for sufficiency!
 
...and

"...I've also seen some amazing things on airliners, as have most of us. The patch with what seems like 2000 rivets just over the passenger entrance? How many times have we seen that?..."

You do realize that there had to be an engineering order to execute that patch, right?

That wasn't just some guy making a TLAR repair on that airliner...
 
"...I've also seen some amazing things on airliners, as have most of us. The patch with what seems like 2000 rivets just over the passenger entrance? How many times have we seen that?..."

You do realize that there had to be an engineering order to execute that patch, right?

That wasn't just some guy making a TLAR repair on that airliner...

Bob, you misinterpreted what I was saying. Ugly repair doesn't mean it's not airworthy. I'm sure the patch of rivets is airworthy, but it sure is ugly!
 
bashing others work

OK OK OK We all admit there is a bunch of &%( out there in the industry.
Having built houses and operated heavy machinery for 42 years I can tell you It is not isolated to aircraft. Yes, I fly and build airplanes also.
There is a lot of stupid people out there doing stupid stuff. My 42 year old son says he can't believe how many stupid people there are in the world.
Had a dozer worked on by professionals. Got it back from shop and the two 1 1/2" through bolts holding the machine together are supposed to be torqued to 650 Foot pounds. Nuts were finger tight. A real HOLY %^@^% moment.
The idea is to catch the problem and fix it before we crash somewhere.
Gittin old has advantages of knowing and learning of the problems before hand
My three cents worth. Art
 
One area of concern for me is that repair advice should be model specific and not just in general terms. One of the recent threads involved an RV 7 rudder and using fillers. JB Weld and bondo were mentioned and a discussion broke out. There are known cases of RV 7 rudder failures ending in fatality. Granted the aircraft were flown passed Vne. But at least one NTSB final report listed poor construction and lots of filler as a contributing factor. Flutter may have been involved. An uneducated builder doesn't know what he doesn't know and may not know whose advise to go with. There are many talented and experienced builders on this forum who try and hold us to a high standard. Lately there seems to be more and more new members giving advice in direct conflict with this. And encouraging others to follow their lead. I may know a lot about building an RV7 (it's been safely flying for over a decade), but advise from me on any other model should be suspect. I get a feeling that there are people giving advice who have neither built nor maintained an RV. Especially on some of the social media sites.

Thanks to Dan H, Bill L, Vic, Walt and others too numerous to mention who keep fighting the battle who try to keep us safe and our insurance rates down.
 
And yet another example of why I spend little time on these forums anymore. Common sense, at times, seems truly uncommon. Folks, safe and pretty have nothing in common. I've seen a lot of pretty girls that can't fly worth a d*&*n.
I apparently need to seek help to address whatever broken part of me keeps me checking in here.....
 
Folks, safe and pretty have nothing in common.

Absolutely true. Couldn't agree more. In fact, let's all agree this ain't about pretty, Lindy exhaust pipe polishing, etc.

Ever seen a fabric airplane with all the tapes sanded through over the rib stitching, along with some of the stitching itself? Remember the thread right here, about the guy who used silicone sealant on pipe threads, so a wad blocked fuel flow and people died? Ever made a TC visit, found really bad riveting down the trailing edge of a zipper rudder, but the builder wasn't interested? I once drove to Florida to buy an incomplete Glastar, only to find rivet work apparently done with a roofing hatchet. And just last week I opened up an RV-4 to find a scat tube wearing through a motor mount. It was built that way.

In every case, it was all about personal standards.
 
I have replaced plenty of parts. I also repaired a few mistakes when it could be done in an approved and inconspicuous fashion rather than spend time and money on an unnecessary replacement just to win the approval of a stranger on the internet. I feel far from miserable every time I fly.
 
What basis for what standards??

In every case, it was all about personal standards.

Big questions is were the standards based on adequate knowledge?

If you were not aware that the SCAT tubing could wear through the motor mount, then allowing them to have contact might be understandable----after all, soft rubber tube vs. steel mount?? Understandable that his standard was lower than others. Not necessarily right, but understandable.

However if the builder knew that could be an issue and still built it that way, then that would seem to indicate he has a much lower standard.

Our current project uses elastic stop nuts to secure the bolts in the control surface hinges. Bronze bushings press fit into the hinge halves and the bolt is the axle they pivot around. I chose to change to castellated nuts and cotter pins. A standard I leaned about from the RV 10 build. Are the elastic nuts adequate for the job? Well, that is what the designer speced, and I suspect most of the folks building these planes are using them without any issues.
 
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I resent the implication that if I don't have an award winner, I'm somehow substandard and unsafe.

I'm not rich enough to have all the idle time I would like. I actually have to work for a living, and I don't have "staff" to raise my family or keep up my household. That puts real limits on my time and my budget - which directly impacts the dollars and hours available during my build, and during my flight time. I simply don't have the budget or the time to spend all day every day at the hangar and constantly jack around with keeping my plane polished and primped just to go win some award that nobody really cares about or will even remember a few years from now. I want to play with my boy, I want to spend quality time with my wife, and I want to go flying.

Every thing on my airplane works - if there is a squawk it gets a wrench immediately. It may have some hangar rash in the paint and it may have a dirty belly, but it is certainly airworthy, safe, and fully functional. I'm sorry that I can't live up to the "extended pinky" standards that some of you ooh-lah-lah people expect. Actually, no, scratch that - frankly I don't give a **** about your opinion of me or my airplane. I didn't build it for you, I built it for me.

I'm happy for you that you are idle rich and can afford to have the absolute best in everything and accept nothing else.

Sometimes this forum really disappoints me.
 
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I resent the implication that if I don't have an award winner, I'm somehow substandard and unsafe.

I'm not rich enough to have all the idle time I would like. I actually have to work for a living, and I don't have "staff" to raise my family or keep up my household. That puts real limits on my time and my budget - which directly impacts the dollars and hours available during my build, and during my flight time. I simply don't have the budget or the time to spend all day every day at the hangar and constantly jack around with keeping my plane polished and primped just to go win some award that nobody really cares about or will even remember a few years from now. I want to play with my boy, I want to spend quality time with my wife, and I want to go flying.

Every thing on my airplane works - if there is a squawk it gets a wrench immediately. It may have some hangar rash in the paint and it may have a dirty belly, but it is certainly airworthy, safe, and fully functional. I'm sorry that I can't live up to the "extended pinky" standards that some of you ooh-lah-lah people expect. Actually, no, scratch that - frankly I don't give a **** about your opinion of me or my airplane. I didn't build it for you, I built it for me.

I'm happy for you that you are idle rich and can afford to have the absolute best in everything and accept nothing else.

Sometimes this forum really disappoints me.

Man, I don't know anybody that fits that description :p but a $60 skin in a $175K project ... well ...
 
After reading a forum thread like this one, I fear my RV8 will fall apart during its first flight. That is if the alcad aluminum skin will corrode due to the lack of proper zinc chromate primer before the first flight.

In confession, I repaired a small number of missed dimpled rivet holes on my horizontal stabilizer and fuselage skin. I replaced the trim tab twice, until I told myself that it was good enough. A dirty word here. Not Lindy quality by far but some of you guys here who are much better at trimming and bending aluminum than I could do. This is why I purchased the pre-punched kit after all. There a few doublers to replace the badly drilled out nutplates where the rivet holes are now enlarged. The list goes on.

I am still flying the flight school Cherokee/Skyhawk specials while finishing up my definitely imperfect RV8, and it is imperfect by all measures (DIY upholstery, DIY paint, and non-constant-speed-propeller, etc...). The rusted AN3 nuts, missing or misformed rivets, or missing cowling screws on some of these +40 years old training airplanes will surely make all of you guys cringe. But you already knew that. We all learned to fly on these contraptions. I just thank God they used safety factor when they designed these airplanes. ;)
 
I resent the implication that if I don't have an award winner, I'm somehow substandard and unsafe....Sometimes this forum really disappoints me.

Self-inflicted pain. The award-winner thing is a distraction, a straw man objection to the real theme, which is...

...serious discussion about attitudes to quality control (or lack thereof) in the Experimental Category.

So let's be serious. How do you encourage personal standards at your level? Think quality, not pretty.
 
OK, so...

"...So let's be serious. How do you encourage personal standards at your level? Think quality, not pretty..."

So who gets to define "quality"?
 
technical counsellor
I think that these guys (I’m one as well), have, if used, a lot to say on quality control.
The US system is quite liberal, as others countries might be, in that a builder or an assembler as she/he should be called today, can troddle around to the end in his own style. With the resultant quality, or lack of.
In other countries a project must have a tech counselor assigned, and he will guide and ascertain a minimum build quality. Well, I certainly do. It ain’t no warrant for utmost build quality, but will bring a minimum level of workmanship and adherence to known aviation practices.
 
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...and

...and therein lies the problem. What your "minimum standard" is, as a TC, will be different from every other TC out there.

I had 4 different TC's look at my build along the way, each with their own "minimum standard".

So I ask again, who gets to define "quality", or in this case "minimum standard"?
 
So who gets to define "quality"?

I'd suggest it doesn't really need definition.

Go back to post #24. I offered four examples. None of them required more than common sense to recognize as a problem.

Grab one of Vic's books. Again, most of the uh-oh's don't require particular expertise to recognize.

So how did they escape the lab, so to speak? Why did the builders accept them as ok?
 
Learning from mistakes

Anybody who says they didn’t make a mistake somewhere along their build is full of you know what. The key is to recognize the error, learn something from it then repair or replace as necessary to meet the required safety and performance standards. As builders this is why we use Tech Counselors, Vans tech support, other builders and/or this forum to learn the proper ways to perform a task. Like we used to say in the Navy, if the minimum wasn’t good enough, it wouldn’t be the minimum. That minimum standard certainly doesn’t make any build “miserable”. If the FAA or whatever authorizing agency that grants your airworthiness certificate and sets the minimum standards says the aircraft is safe, then go with it. If you want a pretty plane to look at in the hangar or be on a magazine cover then by all means take 11+ years on your build. The rest of us that aren’t quite as perfect will be flying.
 
so...

So a "minimum standard" doesn't need to be defined but can be judged by others?

Makes perfect sense...

I would say that AC 43-13 is a good place to start...

I would also say that having witnessed some airworthiness inspections along the way, relying on that inspection to say that the aircraft is "safe" is a bad call...

Again, there really isn't a "minimum standard" for that either...
 
"...So let's be serious. How do you encourage personal standards at your level? Think quality, not pretty..."

So who gets to define "quality"?

Well, here's a top-level definition from my agency:

Quality means compliance with descriptions of intent. These may be found in technical specifications that describe form, fit and function or in procedures that describe how personnel or equipment must progress through various actions. They may be found in minimum criteria for certification or accreditation. The measure of quality may be in test or inspection results, process control data logs, audit records or records of completed work sequences.

Just talking about some mythical thing called "quality" without some idea of what that actually means is a waste of time.
 
So a "minimum standard" doesn't need to be defined but can be judged by others?

Makes perfect sense...

Bob, don't be a cynic. Does it take a written standard to know sanding through a rib stitch is unacceptable? The real question...why did the builder accept it as good enough? What drove his decision?
 
So a "minimum standard" doesn't need to be defined but can be judged by others?

Makes perfect sense...

I would say that AC 43-13 is a good place to start...

I would also say that having witnessed some airworthiness inspections along the way, relying on that inspection to say that the aircraft is "safe" is a bad call...

Again, there really isn't a "minimum standard" for that either...

Agreed, AC 43-13 is good place to start. The builders manual and blueprints are another.

Like I mentioned before, don’t rely on just one source to define that minimum standard. However, ultimately the FAA is the one to grant you that airworthiness certificate. You’re the one who must decide on your build as to wether that’s acceptable, “miserable” or not.

What do you call the last person to graduate from med school? Doctor ;)
 
I'd suggest it doesn't really need definition.

Go back to post #24. I offered four examples. None of them required more than common sense to recognize as a problem.

Grab one of Vic's books. Again, most of the uh-oh's don't require particular expertise to recognize.

So how did they escape the lab, so to speak? Why did the builders accept them as ok?

Posting rule #3.......:rolleyes:
 
As a newcomer to this site, and soon to joint the ranks of first time builders, I'm here to learn from everyone else's experiences. I haven't built an airplane before, but I have enough experience building other things to know that no build is perfect and the key to success is learning to recognize where perfection is required and where the tolerances are wider.

Building an airplane is no different. I know that not every rivet is going to be exactly the same and I have to learn what the acceptable tolerances are so I can recognize when I have to redo the work. I know that along the way the aluminum skins will suffer some deterioration from their pristine factory condition being handled and manipulated, be it scratches, bends or dents. I need to learn how to recognize where these changes fall in the "replace-it-now" - "it'll-outlast-the-aircraft" spectrum, and why. I hope I can learn all these things before I create a life-critical machine, because I want my attention focused squarely on what matters to make a safe long-lasting aircraft, not on distracting cosmetic issues that don't have any real impact on the final product.

Falling back on the old adage, "learn from other people's mistakes, you won't live long enough to make them all yourself", I value the entire spectrum of comments offered in good faith. If enough people contribute their experience, it can be very helpful to the learning process, even if some of those contributions don't meet everyone's standard of "perfection". Critiques of other approaches are also valuable. It helps me see different perspectives while I try to develop my own.

So please, keep the debates going. If you feel something isn't adequate, please say so and explain why. Or if you think it's overkill, explain that too. I know I've appreciated that kind of advice already.
 
After reading a forum thread like this one, I fear my RV8 will fall apart during its first flight.

I sometimes walk away from VAF threads thinking the same thing. My plane is going to fly apart when I start the engine because of that one bolt hole somewhere that I didn't inspect that is 10% out of edge distance spec. Or the tail is going to fall off in flight because a rivet hole is oblong. Should I have used Permatex or RTV for this or that? I often feel like an impostor, and have doubts that my first-time-builder workmanship is good enough. I've made so many calls to Vans, replaced so many botched parts. I've done repairs that I believe are airworthy, but I've only been building for four years so what do I know? The standard of AC 43-13 is large and intimidating, and sometimes I don't even know if I'll find it in that dense book. I have AC 43-13 and have looked things up in it but I don't have it memorized, and I don't sit there with a magnifying glass over each subassembly, looking every decision up in AC 43-13. If I did, I'd never finish the project. Maybe that makes me a bad builder and I'm going to pay for it with my life. That paranoia is always in the back of my mind as I'm building.
 
On the other hand if you look at overall statistics experimental airplanes are only marginally more dangerous then your Cessna or Piper.

Oliver

That statement is entirely incorrect. The truth is that aircraft built in the Experimental Category are hugely more dangerous than factory-built aircraft.

In 2013 the Australian Transport Safety Bureau (Australian equivalent of the NTSB) released a highly researched and extensive document analysing accidents involving VH-registered non-factory-built aeroplanes. The full document can be viewed here:
https://www.atsb.gov.au/publications/2007/ar-2007-043(2)/

The ATSB findings largely mirrored an NTSB safety study into Experimental amateur-built aircraft in 2012. The full document can be viewed here:
http://libraryonline.erau.edu/online-full-text/ntsb/safety-studies/SS12-01.pdf

The ATSB report found that amateur built aircraft had an accident rate three times higher than comparable factory-built certified aircraft conducting similar flight operations between 1988 and 2010.

Additionally it found that the fatal and serious injury accident rate was over five times higher in amateur-built aircraft.

So not only are you much more likely to have an accident in an Experimental aircraft but when you do have an accident the chances that you will be killed or seriously injured are greatly magnified.

And contrary to popular myth the main cause of accidents in the Experimental Category is not pilot error. It is not VFR into IMC. It is not low level aerobatics. Over half of the accidents were precipitated by mechanical events, in particular complete or partial engine failure. In fact the mechanically related amateur-built accident rate is over four times higher than comparable factory-built aircraft.

All of the evidence available points to the fact that we are not doing a good job of either installing or maintaining our engine systems.

You can generally get away with poor workmanship on the airframe but when you take that attitude forward of the firewall it can really bite you.

Incidentally I NEVER said we needed to pursue perfection in our aircraft building endeavours....people just keep misquoting me.
 
There's a whole engineering dept that does nothing but develop repairs for new planes before they even leave the factory!

I did a round as a liaison engineer at Boeing during new hire rotation. When things go wrong in the shop a rejection tag is generated and the liaison engineering department does an investigation as to cause and also helps design a repair for the affected parts. It's all signed of by a production DER on an 8110-3 and becomes part of the permanent record of the aircraft on the spot. In fleet support the stress department approves field repairs or designs new ones for airlines all over the world. I did a lot of patch designs for bullet holes and even elephant tusk damage on the empennage of a 767 in Africa.
 
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I've also seen some amazing things on airliners, as have most of us. The patch with what seems like 2000 rivets just over the passenger entrance? How many times have we seen that?

What you may have there are called bear straps, doublers that are designed into the fuselage to reinforce and distribute the stress from the door cut-outs to the adjacent structure. They taper to properly load every fastener and the resulting shape can look similar to a bear rug around the door. With lots and lots of fasteners. There are also diamond shaped doublers as discrete reinforcements.
 
Judgment and experience

Getting back to the main point of this thread. The builder has the responsibility to exercise good judgment based on his/her experience and take a coarse of actions based on that experience. If that experience is minimal or not pertinent then the correct coarse of action is to seek qualified help. I thought that is one of the reasons for following the VAF Forum if you are building or operating a Vans designed aircraft. I have seen some exceptional engineering and some really poor engineering over a 40+ year career - it just needs some experience to know which is which.
 
I've seen things that bothered me on aircraft, both certified and experimental. What might be very interesting is to hear about the kinds of things you have seen, kind of like when Vic shares his findings.

One of the most common for me is firewall penetrations that have little or no actual fire resistance. Or when you can see that they are not sealed at all.


Yes Mickey, I constantly come across RVs that have firewall penetrations made with nylon snap bushings covered with a blob of "high temperature" red RTV such as Permatex Silicon Gasket Maker or similar. This is crazy. Builders do it because they see other builders doing it. It's the blind leading the blind.

These so called "high temperature" red silicones are only formulated to withstand temperatures up to about 650 degrees F. They're for forming gaskets. Avgas flames generate about three times that temperature. In an avgas fire the silicone will instantly ignite, readily burn, and emit huge quantities of white smoke. That smoke will then transmit back into the cabin blinding the pilot and asphyxiating him. Pilots are worried about fire but the first and biggest problem will be smoke.

The big weakness I find with RV projects is firewall forward. There are so many engine options and it's the area where Vans instructions tend to get very thin. I see a lot of firewall forwards that really worry me, particularly with hoses...hoses that are too short...hoses that are too long...hoses that are twisted...hoses that have a bend radius less than spec...hoses that are not fireproofed...hoses that are chaffing...hoses that may or may not be torqued correctly...hoses that cannot adequately accommodate engine movement...hoses that have crazy routing...hoses that are too close to exhaust pipes...you get the drift.

Part of the problem is that many builders get a set of engine hoses from Vans in their FWF kit and even if those hoses are not a good fit for their particular engine configuration....well, they're going to make them fit one way or another because replacing them is expensive.
 
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In 2013 the Australian Transport Safety Bureau (Australian equivalent of the NTSB) released a highly researched and extensive document analysing accidents involving VH-registered non-factory-built aeroplanes. The full document can be viewed here:
https://www.atsb.gov.au/publications/2007/ar-2007-043(2)/

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Thanks for sharing this. I'm impressed by the work that the ATSB does, and this report is another example of that good work. Very interesting reading, and a good reminder of things that I believe we have all seen over the years that cause crashes.
 
Tell the "VH" world any way you like that delivers the message effectively.

In the "N#" world and likely "C" and "G" and rest of global EAB your message, any message, is lost on you being yourself.

Nothing against any country, I have flown in all mentioned- I'm done reading your hand grenades. You didn't like last week's rudder thread derailment fail, so again you start. You don't communicate well and it is incredibly multi-year consistent. The subject matter is too important to be diluted by driving folks off, at least in VAF. Sell it on your own in your own way, but I'm shocked the mods are so off the mark on missing the, "how" when it drowns out the, "what". This method died pre 9/11 and even in the military now no longer works.

Clean it up, please. VAF is primarily successful because I never see worse than the OP's posts, but I am speaking up twice because the OP is a consistent negative in my views here.

There are places where the "how" does NOT matter and you can fire away however you wish. I thought VAF was the "how" first site.

Now, that said- I'm old school and get what he's saying. However, In real life I get to teach multi-generations and know if you choose to botch or not correct the how, the what is going to not be heard, then soon someone else is where they go to learn.

I'd hate to see that here. Please quit room clearing with hand grenades. I used to tolerate a good message spun in pontification, but not two weeks in a row for pure self aggrandisement masked in "safe practices".

Signed, retired USAF safety chief way down under one of the VAF mods.
 
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