Van’s Aircraft Laser Cut Parts

UPDATE January 12, 2024
I watched the full two hour Van’s Engineering Presentation – Laser Cut Parts video and
KITPLANES Roundtable on Van’s Laser-Cut Parts Tech Briefing video

I was left impressed by the level of detail and how extensive the testing that was completed on the laser cut parts (and punched parts). And yes I was surprised to find that the dimpled cracks did not propagate and when stressed to the limit, cracks formed in other areas. So with that I take back a lot of what I originally wrote. The analysis still shows that punched parts are stronger and will lead to a longer life expectancy, but with the super high lifetime hour estimate it doesn’t make much difference.

I’m still happier to have punched parts and think that it gives my plane a slight increase in value but if I was still building today, I would replace whichever parts I could but not worry about any LCPs that I installed. On another positive note, you can destroy the RV-10 wing and it will still get you home! CRAZY the destruction they did and it still supported the aircraft!

ORIGINAL POST November 12, 2023
I feel unbelievable lucky to have built my plane before Van’s switched fabrication methods in 2022 from CNC punched to laser cuts parts. Yes, I know, there have always been some laser cut parts (minor things like the engine baffles) but those parts were fabricated by a qualified supplier who programmed, monitored, adjusted their machines correctly PLUS those parts were not structural. But back in the heyday of Covid with Van’s struggling to keep up while annual doubling in size they made the decision to make the wholesale changes to most models and added a new supplier for these parts. It took time for builders to use these parts in their build and evidently a ground swell occurred around late June as these parts exhibited cracking around the holes (mostly when dimpling). Van’s acknowledged this was occurring issuing their first statement in July 4, 2023, providing that these parts were fabricated from February 2022 to June 2023.

July 4, 2023 Van’s first released their Laser-Cut Parts Engineering Evaluation, explaining the issue and that they were evaluating the issue. In this publication was, “Van’s will replace any laser-cut parts which are dimpled by the builder during the construction process, upon request, as soon as we are able to do so based on parts availability.”

From Van’s Laser-Cut Parts Engineering Evaluation, dated Sep 24, 2023
“Residual Strength Testing
Industry testing standards also direct aircraft designers/manufacturers to assess the resilience and strength of aircraft structures in the event of various forms of structural failure. Therefore, additional conservative testing simulating a fully developed, undetected fatigue crack was performed on a complete RV-10 wing. A series of static tests under limit load was conducted, in which every main and nose rib was cut completely across the part in multiple locations, simulating failures at all elevated stress locations. Ribs were completely severed at the spar attachments, at relief notches, and out of fastener holes. This was a progressive test, starting with the most highly-stressed parts and progressing through the rest of the wing, including tank internal ribs and the tank baffle. This test simulated extremely unrealistic failures, well beyond that which could ever actually occur. This test demonstrated that the structure maintained its strength and function in an absolutely unrealistic and negligent scenario.”

In October 2023, I posted on VAF my opinion which I continue to stand by,” Why wouldn’t anyone with unassembled sections not replace all LCP parts? No doubt if you every sell your plane that is going to be the first question asked by the buyer. Such a low added cost at that point.

For everyone further along, I feel for you. That is a hard pill to swallow. Personally, I would rebuild from scratch any sections that contain LCP parts and throw the original in the junk bin. I would not want to spend my life worrying about what could happen down the road, no doubt in my mind that there will be many SB in the future for builders who used LCP parts.”

Subsequently Van’s has published Service Letter 00091 – REV 1 dated Nov 11, 2023
“All testing to date has shown that there is no immediate airworthiness concern for aircraft with laser cut parts. In addition, there is no
immediate need to replace laser cut parts that are already installed in an aircraft prior to inspection for certification. Van’s Aircraft has conducted an analysis of the airworthiness and service life of these parts. A summary of this investigation, “Laser-Cut Parts Engineering Evaluation,” is available on the Van’s Aircraft website.”

Direct questions to Greg at Van’s have gone unanswered as to when cracks are acceptable. From FAA AC_43.13-1B, I would argue that cracks are never acceptable. But by saying to keep on building and that these parts are not an “immediate airworthiness concern” I interpret that to mean that Van’s is saying cracks are acceptable. Which I find insane.

November 11, 2023 From VansAirforce, Tlrguy writes (directed to Greg Hughes at Van’s):
“Can you provide some guidance for what crack size and frequency is acceptable Greg? I have many parts with 90+ percent of the holes cracked. If I’ve missed this guidance, please point me in the right direction.”

November 11, 2023 Van’s Aircraft verified Facebook account posted the following response to Rodrigo Damazio Bovendorp in the Van’s Aircraft Builders group:
“Tim Walmsley Actually it’s an SL not a SB, and it says to refer to the engineering analysis document. That analysis document says – as an outcome of the extensive testing performed – that even with cracks present in the edges of dimpled holes on laser-cut parts, they are structurally sound and acceptable for use, except for those parts that we have classified as recommended for replacement.”

November 13, 2023 From VansAirforce, Gmcjetpilot writes:
“I was a aircraft structural engineer in a previous life (first Career). I worked for Boeing as a direct and contact engineer for Airbus, British Aerospace, Lockheed, P&W and several airlines. In my opinion cracks are not acceptable. Period. It’s just a standard.

With that said CRACKS happen. Fixes include, stop drill crack top (normally not a permanent repair), cut crack out and put in repair, filler/doubler, and #1 most preferred and accepted is replace the cracked part.

Can a crack exist and be OK? I would say no, unless it is inspectable and you inspect it often.”

It scares me that Van’s has published VAD-10041 R6 titled “Laser Cut Parts List” dated Nov 10, 2023 shows the vast majority of laser cut parts are okay to use. This reinforces that they feel cracks are acceptable. This flies directly in opposition to everything I have read about accepted best practices for aircraft. Many of the parts with potential for cracking are buried deep in assemblies and impossible to inspect. I fear we will see lives lost if these planes are completed and flown with these, at best, inferior parts.