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Fuselage longeron repair scheme?

Lars Jensen

I'm New Here
Hello All RV-enthusiasts.

I have recently bought an RV6A, after it had done the forward flip.. The result was a damaged firewall, wrinkled fuselage skins and fuse longerons bent and pushed outwards as the roll bar came down. The damage stops forward of the tailcone. The event was videoed so just Youtube: RV6 G-CCVS.

This kind of damage has been seen before, and I have been searching for a repairs having been done to the longerons, avoiding to replace the entire tailcone, which was not damaged in the flip. I want to repair replacing the longerons from the (straight) baggage section and forward, placing a doubler across the longeron.

Doing a repair according to AC43-13 should be fairly straight forward, but has anybody done this to date with an approved repair? My issue is that I need to get the repair approved by the LAA here in Britain, and they will want to see a scheme based on either Vans recommendation or AC43-13.

Being a follower of RV for two decades I am new to the RV community, but have overhauled a couple of certified planes in the past, I just got enough of the EASA paperwork in Europe and have seen the RV coming my way for a long time. The RV6 is not that far from my beloved CAP10C in flight characteristics, so now I am giving the RVs a try.

Let me know your advise, or a pointer to the thread where this has been beaten before.

Cheers

Lars Jensen
UK

Robin DR253b D-EGCC
CAP10c D-ETUR

plus more..
 
Call the factory. One of their guys spliced a new tailcone onto his RV-6 after a wayward car hit it about 20 years ago. You're doing a similar splice.
 
I did mail Sterling at Vans, and got the reply; "we recommend changing out all damaged parts." That would involve deriveting the entire rear fuselage, which is what I am trying to avoid.

The attitude to repairs at Vans may have changed over the years.

Forgot to mention it is a Quick Build from 1999.

Cheers
Lars J
 
Probably worth speaking to LAA Engineering first. You want them to be satisfied from the outset. Have you got an LAA inspector for the project?
 
Welcome to VAF

Lars, welcome aboard the good ship VAF:D

Good luck with your project.
 
You could remove and replace one longeron at a time.

And although it would add a few holes that you'd need to fill, you could rivet on a few pieces of sheet that go across the longeron rivet line (first removing just those longeron rivets) and ensure that the overall alignment is maintained. After the new longeron is installed and mostly riveted, you'd remove these pieces, finish riveting the longeron and rivet in those new holes to fill them.

Dave
 
I am definitely going to get the LAA onboard, but the question is asked to see if anybody has gone down that route already; meaning has anyone made a documented and approved repair, which I can be fairly sure will be accepted by the LAA.

I just hate reinventing the wheel, again..

Cheers
Lars
 
I did it on a partially built RV-4 kit. It?s not that difficult. Just a lot of rivets to drill out.
 
Ken Scott

Call the factory. One of their guys spliced a new tailcone onto his RV-6 after a wayward car hit it about 20 years ago. You're doing a similar splice.

I did mail Sterling at Vans, and got the reply; "we recommend changing out all damaged parts." That would involve deriveting the entire rear fuselage, which is what I am trying to avoid.

The attitude to repairs at Vans may have changed over the years.

Forgot to mention it is a Quick Build from 1999.

Cheers
Lars J

That was Ken Scott, N207KS. He retired from Van's in July of 2016. Maybe you can find a way to get in touch with him.
 
Robin, I have been on a similar wreck rebuild for a couple years, I am slow, and my plane was much more substantially damaged than the one in the video I just watched...I believe. I straightened one longeron and if I was not able too I would have just replaced it. With all the other structure in place the plane stay's square. Providing it was not to tweaked in the turn over.

I am not familiar with the repair procedure you noted but will take a look at that and see if my process was in line with the procedures and add more here in a bit.

OK...that circular is 646 pages long...uh...wow.

Looks like Sec. 4:11-56, and then spots throughout the 646 pages. The distance of deflecting of longeron from baseline is where I would start. And, in an experiential sense, does the AL have "cottage cheese" look to the bend? Not very scientific but if I see "other than" original flat dimensional surface I replace it as obvious metal structure has been changed. I am sure a metallurgist can give this a proper name here. I hired my foundry guy so I didn't have to know all that stuff.
Now, I am not an engineer, I have hired engineers to check my math and show them ways to manufacture stuff cheaper, faster with fewer tool changes... haha but that is just because it is my wallet. I have learned a lot from engineers.
 
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Don’t know if he’s still repairing it, but it’s permit hasn’t been renewed since 2017
 
Work still in progress

Hello all,

My rebuild is still ongoing, but a job abroad combined with Covid put a stop to any progress since 2019. Now, free from employment, work on the RV will resume next month.

The plan is still to splice the longeron behind the seat and the main structure is drilled and cleco’d by now.

Hopefully the next update is not three years away..
 

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