Factory Info: Parts with Laser Cut Holes and Potential for Cracks

[Bullpup]

Not really the case, I've been around manufacturing and repair for a long time, (I was heavily involved with G5 wing manufacturer) and although mistakes do happen, they were/are taken care of on a case-by-case basis with an engineering order for a specific problem, ie: an oversized hole. Never saw a case or situation where the entire assembly was made with defects and covered by a 'blanket' EO.

This hits the core of the issue for me. In a prior career I signed many nonconformance packages (military), but each was specific to the situation at hand. There were occasions where the mediation led to changes to the plans and/or shop instructions, but the paperwork requirement was higher for a wide-reaching change than for a specific part.

There is an accepted process in certified aviation (I know we're not there, but the lessons stand) - when you find, as Vans has, that the prior guidance may have been overly conservative and is resulting in either the scrap of actually OK parts, or causing a paperwork and engineering burden to adjudicate each case individually, you can update the plans to reflect the new standard.

I don't understand why Vans has been unwilling or unable to do this - we need some guidance on what exactly constitutes acceptable cracks in LCP. I have no idea if any given part I'm working on falls within the range tested, how many are acceptable, etc. The engineering assessment would have failed my undergraduate structures homework, and just isn't complete for what they're asking. The required documentation to cover hundreds of parts, in thousands of combinations, in multiple airframes would take much more than a few pages with no quantitative data. It wasn't even clear until the 2nd revision that the tested parts had visible cracks!

If we had solid guidance to go on, many would still choose to not use LCP (as is their prerogative), but at least we'd have some standard to build & inspect to.

Remember, 6 months ago the red parts were OK for use - we need a little more documentation before we can really trust that "this time is different".

 

[spatsch]

Not really the case, I've been around manufacturing and repair for a long time, (I was heavily involved with G5 wing manufacturer) and although mistakes do happen, they were/are taken care of on a case-by-case basis with an engineering order for a specific problem, ie: an oversized hole. Never saw a case or situation where the entire assembly was made with defects and covered by a 'blanket' EO.

Your comment confuses me. First half seems to imply that in aircraft manufacturing no rework happens on airplanes sold as new and the second half outlines the process for doing the rework.

So does rework happen or not?

Thx

Oliver

 

[KatanaPilot]

Well its common practice for manufacturers to rework assemblies before shipping and sell them as new. If car manufacturers discarded every car that needed rework when it comes of the assembly line cars would be much more expensive. Lycoming did that to me on a new engine. It’s annoying if you know about it but most times you don’t …. .

So in this cases you have two kind of affected qb kits. The ones that shipped already to the customer and the once that haven’t.

Oliver

Not the same thing. Rework along the likes of plugging in a missing ABS module or radio is considerably different than reworking an assembled QB kit.

As does Boeing, Airbus, Embraer, and yes, even Gulfstream!

And everyone you named is an aircraft manufacturer. Other than the pop-riveted S-LSA RV-12, Van's manufactures kits. The manufacturers (and component suppliers like Spirit) use specially trained Tiger teams to do rework (like the P-dome on the 737 Max). Rework/repair is different than assembly.

Not really the case, I've been around manufacturing and repair for a long time, (I was heavily involved with G5 wing manufacturer) and although mistakes do happen, they were/are taken care of on a case-by-case basis with an engineering order for a specific problem, ie: an oversized hole. Never saw a case or situation where the entire assembly was made with defects and covered by a 'blanket' EO.

And this is the concern of many current builders summed up succinctly by an unimpeachable source.

 

[lr172]

I What we need is a line in the sand along the lines of "nothing visible under 10x magnification" or similar.

And generally the way that engineers find and define that line are by doing large scale fatigue cycling (that match the intended use patterns) to either numerous lifetime cycles or to destruction and observing if, when and where those cracks lead to propagation or other failures. Kind of sounds similar to what Vans did.

 

[airguy]

And generally the way that engineers find and define that line are by doing large scale fatigue cycling (that match the intended use patterns) to either numerous lifetime cycles or to destruction and observing if, when and where those cracks lead to propagation or other failures. Kind of sounds similar to what Vans did.

Agreed.

But they did not release all their test results/procedures (which they don't have to), and probably won't because as soon as they do all the armchair engineers will start picking holes in the testing. I don't blame Vans one bit for not showing how the sausage is made, you either eat it or don't.

This release of testing data falls under the same umbrella as the Vne testing and flutter testing - Vans tells us it was done, and that's it. You can either accept that it was done and abide by their guidance, or not accept it and go pick another hobby.

Don't get me wrong - I'm not saying Vans in wrong in that approach - I think it's the only safe path for them given the abundance of armchair engineers on this thread. You're not ever going to make everyone happy.

 

[Bullpup]

And generally the way that engineers find and define that line are by doing large scale fatigue cycling (that match the intended use patterns) to either numerous lifetime cycles or to destruction and observing if, when and where those cracks lead to propagation or other failures. Kind of sounds similar to what Vans did.

They may have "defined the line", but they neglected to tell us where it is... it took until the 2nd revision to be clear they tested parts with cracks!

 

[N82VM]

I don't see the nexus with hypervigilance due to the ability to see things with magnification.

The cracks are visible to the naked eye. no magnification required.

 

[airguy]

.

The cracks are visible to the naked eye. no magnification required.

In that case, the part should be rejected, I don't think anyone here would argue with that. I know that part is not going on my airplane.

But to demonstrate the fuzziness of the line - is that the naked eyeball of a college-age fighter pilot with exquisite 20/10 vision? Or the naked eyeball of a 53 year old that wears glasses for driving? With or without glasses? What about after Lasik? What kind of lighting do we have for the examination? Natural sunlight or artificial? LED or incandescent?

No matter how fine the line we try to describe - there will always be those that that will try to delve deeper into the details - we won't ever be able to stop that. What I'm saying we need is very similar to the Vne research done by Vans. "This is Vne, don't exceed it." - quite simple, no wiggle room. Those that want to nitpick with arguments about TAS/IAS or temperature or pressure or humidity levels or G-loads - they may find themselves arguing the fine lines in an NTSB report, but that is not Vans problem.

Same here - I would like to see something along the lines of "not visible to the naked eye" or "not visible under 10x magnification" and then Vans can simply sit back and ignore all the "fuzzy line" people arguing about the clarity of that research. If you don't like how fuzzy the line is, then don't approach it. That person can either inspect all their parts with an electron microscope and reject 90% of them, or find another (hopefully less worrisome) hobby.

And maybe the answer is that the red/yellow/blue/green definition IS that line - and we just have to learn to shut up and accept it, or walk away. I won't accept blue, I choose to replace them even if it's at my expense, that's the closest I choose to come to that line. My personal choice.

 

[bmellis11]

I don't see the nexus with hypervigilance due to the ability to see things with magnification.

The cracks are visible to the naked eye. no magnification required.

I was about to say the same thing. I just looked at some of my dimpled and primed LCPs that haven’t been installed yet and every hole has a crack that is easy to see with the naked eye. There were several times when I was riveting LCPs where the dimple split open under the pressure of the rivet head at the crack. None of my punched parts have had those problems.

 

[ccarlson]

The cracks are visible to the naked eye. no magnification required.

This is where it falls down for me as well - I can see the cracks with the naked eye. In fact, that is how I became aware of this entire issue. While admiring my dimple work on VS-702 and VS-803PP, I noticed what appeared to be tiny cracks in the rim of many holes. I figured it was probably just light playing with my eyes, but decided to inspect with magnification.

I started with 10x, then went to 40x. Better than 90% of the dimpled holes in both parts - vertical stabilizer spars - were cracked. I have since inspected numerous dimpled holes in both laser cut and punched parts (punched parts sourced from four RV kits [2x14A, 1x6A, 1x7] being assembled in our EAA chapter hangar). Even with 40x magnification, I have not seen any sign of cracking in the punched (non-laser cut) parts.

Note: I am not saying "microcracks" aren't a thing. In fact, they have probably been present all along and would be visible with the proper amount of magnification. If LCP and non-laser cut parts both exhibited the same frequency and scale of microcracking at a given magnification ("standard microcracking," if you will), then I would consider the parts to be metallurgically equivalent. The fact that LCPs have cracks visible to the naked eye tells me they are not metallurgically equivalent.

In a nutshell: my observations indicate (to me) that "magnification bias" is not a factor.

 

[N82VM]

In that case, the part should be rejected, I don't think anyone here would argue with that. I know that part is not going on my airplane.

But to demonstrate the fuzziness of the line - is that the naked eyeball of a college-age fighter pilot with exquisite 20/10 vision? Or the naked eyeball of a 53 year old that wears glasses for driving? With or without glasses? What about after Lasik? What kind of lighting do we have for the examination? Natural sunlight or artificial? LED or incandescent?

No matter how fine the line we try to describe - there will always be those that that will try to delve deeper into the details - we won't ever be able to stop that. What I'm saying we need is very similar to the Vne research done by Vans. "This is Vne, don't exceed it." - quite simple, no wiggle room. Those that want to nitpick with arguments about TAS/IAS or temperature or pressure or humidity levels or G-loads - they may find themselves arguing the fine lines in an NTSB report, but that is not Vans problem.

Same here - I would like to see something along the lines of "not visible to the naked eye" or "not visible under 10x magnification" and then Vans can simply sit back and ignore all the "fuzzy line" people arguing about the clarity of that research. If you don't like how fuzzy the line is, then don't approach it. That person can either inspect all their parts with an electron microscope and reject 90% of them, or find another (hopefully less worrisome) hobby.

And maybe the answer is that the red/yellow/blue/green definition IS that line - and we just have to learn to shut up and accept it, or walk away. I won't accept blue, I choose to replace them even if it's at my expense, that's the closest I choose to come to that line. My personal choice.

Mine are all cracked so should be rejected.
Back to the beginning, Vans provided parts that are resulting in a high rejection rate. Sounds like they are not produced to expected standards. Which means I did not receive what I expected. Which is why they should be replaced at Van's expense regardless of the "loads" or what ever the color wheel says. A part is a part, and not to standards.

 

[ccarlson]

Some of us just want to hear any info we can get. My goal is not to be in one camp or the other. I just want to keep building the plane I ordered and not have to pay for it a second time. Right now I just want to hear anything official (from Vans) or unofficial (so and so just got parts delivered, or whatever).

1000000%

I’m not in a camp, unless “I want to hear something definitive from Van’s” is one of the camps.

 

[airguy]

I’m not in a camp, unless “I want to hear something definitive from Van’s” is one of the camps.

I have a feeling that this whole issue is being kept quiet at the moment from Vans due to lawyers and insurance claims, and we won't get anything definitive until they are done pushing paper.

 

[Brantel]

I have a feeling that this whole issue is being kept quiet at the moment from Vans due to lawyers and insurance claims, and we won't get anything definitive until they are done pushing paper.

This has to be the only logical explanation for the total radio silence.

 

[mtebbe]

Food for thought?

Instead of slamming the phone and email lines at Vans, let's randomly "spam" the company with gift/cheese/meat baskets, pizzas for the team, donuts, etc... anything to show our support. From my personal experience visiting them, and interfacing with the company, they are a very tight-knit group. They truly do deeply care about their customer-base and I'm sure the team is/was as devastated as you/we were to hear about the LCP situation.

You've (collectively) said that you're not worried about spending a little more to get "LCP-Free". Put a little money where the mouth is and show some support to the company producing your replacement parts. Remember, we're all human and trying to survive this crazy ride of life, together.

 

[Brantel]

This was posted earlier today. Maybe this thing is about to move off bottom dead center?

 

[Sallcock]

I've just spoken with Vans re the current situation (I have a 10 QB for wings and fuse plus the finish kit paid for and was meant to have been delivered in September).

I was told that there's going to be an announcement in the next week as they've been gathering up the stats for the various orders that they have for both parts and QB's.

So hopefully we should hear something in the next 8 days.

Fingers crossed

 

[TX_Flyer]

For what it is worth, some parts I had ordered just prior to the LCP announcement shipped today. I was rebuilding my elevators anyway and all LCP had been held on backorder prior to today, so maybe there is light at the end of the tunnel.

 

[DeltaRomeo]

Update:

10/27/2023 1900Z
https://www.vansaircraft.com/2023/10/business-announcement-from-vans-founder-dick-vangrunsven/

Temporarily closing this thread so folks can have time to watch the video, read the text, and reflect on this. Will re-open over the weekend. v/r,dr

*posting rules