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Vans Wing Attach Service Bulletin Procedures (merged thread)

Really??

I guess some folks were so focused on dealing with the close-tolerance bolts that they forgot the others?
 
I know somebody who had them missing I believe until the first Annual. I counted my 10 bolts in each wing many times before I moved on. Yikes!
 
photo possible?

thanks Lorne;
I know its difficult, but for us non-builders, sure would be nice to know what we are looking for;
any chance someone ( or Van's) has a photo, ideally with and without the bolt visible?
..and what exactly does it DO?...if aircraft are flying around without it?

thanks
 
I guess some folks were so focused on dealing with the close-tolerance bolts that they forgot the others?
Click to expand...
It's quite hard to blame the builders for not putting in bolts that Van's forgot to include in the plans :( NB the Revision issue of the RV-8 drawing, guess what changed in Revn 1 ;), and no alert put out to those who were building to Issue 0.
 
RE: Plans Pix

flyboy1963 said:
thanks Lorne;
I know its difficult, but for us non-builders, sure would be nice to know what we are looking for;
any chance someone ( or Van's) has a photo, ideally with and without the bolt visible?
..and what exactly does it DO?...if aircraft are flying around without it?

thanks
Click to expand...

Perry, maybe this will help. I will also try and get a picture of that area out of my build log pictures later. This is plan set 11 for an RV7A.....

nfexv.jpg


6xsyno.jpg
 
wing attachments on a 9

For clarification the SB is addressing the two bolts each side (right and Left wing) that can be seen on my 9 only from the REAR side of the centersection spar when you remove the floor panels. These actually along with the spacer stiffen the web in that joint. On my 9 I was a little alarmed when looking from the front and seeing "holes" come to find out there is nothing to bolt to on the FRONT side of the joint. Maybe those get something when you bolt on gear assemblies for the 9A . ONLY on the rear side do you find the two AN 4 bolts that thread into the nutplates in the mid section of the assembly. 75 screws later : Oh well any way the floor panels needs removing and cleaning out as well as a closer look at the control linkage.
 
And I did make some pictures

Send me a text message to 77082334 Twenty six and will return a couple to you. That will be easier than me trying to put pictures on VAF. DRR
 
New Service Bulletin 12/08/12

I accomplished the SB on my -9A today. I verified I had the 4 required AN4-13A bolts and washers on both center wing box locations. I accessed the nutplates from the bottom of each wing by dropping the gear leg to fuselage fairing, then dropping the lower portion of the wing root fairing. With a flashlight I was able to see the described nutplates and 2-3 threads of the described AN4-13A bolts protruding from said nutplate. It took less than 30 minutes to verify and enter in airframe log. Dan
 
Completed the inspection on my "8" yesterday. There was no way to get in through the fairing slot. Pulled the floor and foot wells for access. The area was very visible this way and all bolts were properly installed.:)
 
Vans Wing Attach Service Bulletin Procedures

I complied with the SB last night for my -8A. Found that removing the wing root fairing didn't work - I had to remove the fwd seat and loosen the front of the footwell floorboard to get a peek at the subject AN4 bolt heads (I had installed them).

FWIW - you may find a way to make the easier fairing removal work.
 
Review your construction photos...

I looked through my construction photos and had several showing them installed... although I was sure that they were, it was nice to see the shots and it is fun to visit memory lane of the build.
 
9A

Did my 9A today, but did not remove the wing root fairings as I knew this would be a waste of time if the bolts were not fitted, and could casue damage to the paintwork.

My advise if you dont have a camera that look there is just to remove the floor. It takes less than an hour, in my case only to find that I had done it right in the first place.

However, what Schrito says makes good sense for everyone. I have now started to photograph every finished up part on my 4 primarily because my Inspector has failing eyesight. I now have a photographic record of all nuts tightened with 1.5 threads showing which I can blow up so he can see it.
 
SB complied with on RV-7A

I just finished the service bulletin inspection. No bolts. I built it, my mistake.
I can only guess after the time getting the 8 close tolerance bolts in I completely missed them. Don't remember them from the plans (tho 7 years ago now, and they WERE on my plans when I checked today).
Glad the bulletin came out, and once again VAF got me the info immediately. Thanks!
 
best access, from fairing, or floor ( inside)?

Ok, first I have to get over that I had all this open last month during annual!
....so where can you view these bolt heads? from the outside, if the wing/fuse fairing is removed, or from the inside, under the seat? ( you guys are saying 'floorboards' but I think I'm right to say, 'seat pan'.)

I guess I might just have to spend another day at the airport NOT flying and figure this out myself eh? :(

oh, and this is the middle of a month of the best weather all year. :( :(
 
Perry

Perry, if you're down South for any reason, swing by and I'll show you where these bolts are on my 7a. The plans are pretty clear though. I have a bore scope you could borrow as well if you like.
Lorne
 
in search of RV's ! :)

thanks Lorne, would like to meet you & see your ship.
I might be able to view a -7a under construction in Vernon this weekend on a drive thru, seeing how I'm grounded until I do this!
Last week I had a battery squawk so missed flying into Oliver, but drove down for breakfast! Good show!
 
Pictures at annual

I usually, during the condition inspection, take pictures of the areas under the floors, and behind the rear bulkhead, just as a reference. Although
those bolts were not the target of my pictures, I could see them.
 
On a 7 or 9

You can possibly "see" the bolts thru the push pull aileron control hole in the fuselage if you remove the wing faring. Might be good to have on hand one of the fiber optic scopes. If you want to " touch" the hex head or check the other wing attachments while you"re there you may as well pull out the floor panels ie floor pan or control stick access cover. These are the removable panels you sit on. Either way not a major job.
 
New Service Bulletin 14/08/12

Flyboy963: See my post, last one on first page on my computer, from guccidude1. I explain how I verified my bolt installation from the bottom of the each wing. Dan
 
time to head to the field!

I think I'm getting it; heads are visible from inside fuselage,
nutplates are visible from below thru outer bottom wing fairing cover gap.
...and who knows, It might show in some photo i have from the annual....good idea!
( think I'll open 'er up anyway and take a new pic to prove compliance to myself, god & the MOT!)
 
Opened one of my condition inspection albums and found the pictures. Those four bolts are in. When I did my condition inspection I always take pictures. It helps in situation like this.
 
[email protected] said:
I looked through my construction photos and had several showing them installed... although I was sure that they were, it was nice to see the shots and it is fun to visit memory lane of the build.
Click to expand...

Dang it... looked at the log last night. I took shots of every enclosed control system connection (because I was totally OCD about them) but did not get a shot of these bolts in question.

Borescope is a great idea. I assume it is fed down the control stick hole on the 7/9 designs.

******Update edit *******
I couldn't come up with a borescope so I did it via brute force. Yanked the seat pans. Bolts were there.
I have aileron boots installed and I was not sure I could see the nutplates through the spar hole by removing the fairings. Took about 90 minutes.
 
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Just came back from the hangar. On my RV 9 I removed the seat cushions and stick boots and ran a fiber optic scope past the 2 outer seat ribs. The bolts were easily visible. It took 20 minutes all together and I was done. Quick, easy!
 
Early -8 builders look at Drawing 11

My plan set was received circa 1999. There is no Drawing 80, rev1 as indicated in the SB 12-08-14. In fact the highest number drawing I have is 49.

With a little digging I found the proper drawing -- it's number 11. The AN4-13A bolts et al are noted as Revision 2 issued 7-14-97. The parts callouts are somewhat different than the SB lists, so I take it more than just the drawing number has been revised over the years.

Chris
 
ArVeeNiner said:
I know somebody who had them missing I believe until the first Annual. I counted my 10 bolts in each wing many times before I moved on. Yikes!
Click to expand...
Um, that might be me.

Back in 2007 I posted this thread on the subject.

I'm a bit surprised it took Van's this long to come out with a Service Bulletin.

The good news is, the plane will fly without those bolts. The real question is, how many G’s can you pull before the spar buckles.
 
Done.

Accomplished this on my -7 over the weekend. Since I had the aileron rod boots, you can't see through the wing fairing. I looked at the front of the spar, found the two open holes and thought "c$#p! Then proceeded to pull the seat panels and found that I indeed had installed the bolts during construction and realized that these only go through the forward aft spar face.
 
Did my -7a today. Trying to see anything after removing the top portion of the wing root faring was impossible for me and a waste of time. Plan B was going underneath and removing the gear leg top / fuselage faring and the short section of wing root faring present. Bingo, plate nuts with protruding threads easily visible, no inspection mirror necessary; inspection complete and buttoned up in about 20 minutes.

Erich
 
RV-8A time for SB verification 3.7 hours

Yeah, I just put these in 3 months ago but didn't take any pics.... I had a bear of a time getting the 8 close tolerance main spar bolts and the 8 close tolerance "side bolts" installed - took me a total of 14 hours for all of them! Getting the lower bolts in around the gear weldment on the 8A is a really a challenge! The four AN4 "middle bolts" that are the subject of this SB were all very easy - even with the aileron push rods already in place.

I wanted pics in my Builders Log so I did the SB verification this morning. Time to take out the front seat back, remove about 50 sheet metal screws holding the front floor panels down, take the pictures and close everything up was 3.7 hours. I should add that I did wrestle with three of my button head floor screws so that slowed me down 15-20 minutes or so.

Side note: Wow those little holes in the sides of the rear seat foot well sure let a lot of junk get into the area below the floor panels. I did a good vacuum (again) while I was in there.

Al Thomas
N880AT
RV-8A QB
Getting ready for DAR inspection
 
Did our 7A inspection. Remove top portion of wing root fairing and find the two nut plates by standing in front of the wing. If you see threads sticking though the nut plate ou are good to go.
Phelps
 
Spar Bolt SB

Sorry guys, I may have unwittingly contributed to the timing of this SB being issued (& causing your extra work).
A couple months ago I quiried the Vans tech support desk folks how to deal with a RV-8 that came in for a pre-purchase & had these bolts missing. Making this situation more interesting, the spar nutplates were also missing. I worked out with the Vans folks how to rectify the problem by installing AN365 nuts in the very tight space inside the spar carry thru. This involved much cursing, cramped fingers & customized wrenches.
I had mentioned this was the THIRD RV I had inspected with these bolts missing. I also mentioned I also had run into TWO RVs that the builders did not install the row of AN507 screws in the belly to lower wing skin overlap.
This proves the folks at Vans are listening to our experiences and are reacting!
 
s24789 said:
Did our 7A inspection. Remove top portion of wing root fairing and find the two nut plates by standing in front of the wing. If you see threads sticking though the nut plate ou are good to go.
Phelps
Click to expand...

I did the same this weekend. You also only have to remove one side as you can take a mirror and flashlight and see all the way to the other side and see the threads sticking out of the nutplates as well. I think it took something like 8 minutes to comply with the SB.
 
RE: SB Complete

I did the SB today by removing the forward seat pans. Took pictures to prove to my faulty mind that the bolts were placed correctly. Took about an hour to complete.
 
JPrice

All four AN4-13 bolts were not installed in my RV9A. I could not align the bolts to the nut plates in the wing spars. I am not the builder and in the previous two condition inspections was unaware of this problem until this service bulletin.

I need some advice here. Any suggestions anyone?
 
jlprice said:
All four AN4-13 bolts were not installed in my RV9A. I could not align the bolts to the nut plates in the wing spars. I am not the builder and in the previous two condition inspections was unaware of this problem until this service bulletin.

I need some advice here. Any suggestions anyone?
Click to expand...

Call Van's.
 
Try using a tap...

jlprice said:
All four AN4-13 bolts were not installed in my RV9A. I could not align the bolts to the nut plates in the wing spars. I am not the builder and in the previous two condition inspections was unaware of this problem until this service bulletin.

I need some advice here. Any suggestions anyone?
Click to expand...

Perhaps the threads of the nutplates suffered a bit from tapping on the bolt... Try running a tap into them first.
 
Me Too

I will add a data point and some advice. I checked for the bolts on my 9A (bought, not built) by pulling down the wing-fuse fairiing and looking in with my cheapo Harbor Freight borescope. It clearly showed there was NO BOLTS in the nut plates. Tonight I removed the seats and seat pans to install the bolts, which I had on hand. They were really tight and would not thread in, so I ground a little cone on the end of the bolt, ran a nut over it to make sure the threads were good, wiped on some anti-sieze lube and used a cordless drill with an extension and a universal joint to crank the bolts in. I had to put a couple of washers in the socket so I could push while spinning the bolts. They spun right in this way. Then used a torque wrench to tighten to specs. After replacing the thousands of seat pan screws and the seats, I had to take it out for a test flight, of course. It flies so much better now.
 
completed the inspection today. Took a couple of hours, but got a chance to clean the seats and inspect/lube every thing else.
 
15 minutes

We checked the bolts on my -8 by removing the fairings and using an inspection mirror and flashlight. Once we figured it out on the left side the right went quickly. It took longer to take the fairings off and put them back on than to find and check the bolts.

They were there (phew). I did not build this plane but so far everything the builder did structurally was done well. Not so much on electrical - adequate and safe but not neat or well done. We almost completely rewired it last winter so his wiring is no longer a factor.
 
N941WR said:
Um, that might be me.

Back in 2007 I posted this thread on the subject.

I'm a bit surprised it took Van's this long to come out with a Service Bulletin.

The good news is, the plane will fly without those bolts. The real question is, how many G?s can you pull before the spar buckles.
Click to expand...
Could someone explain the functional purpose for these bolts? I pulled the seat pans out to find my spars did not have the bolts installed. And I was the installer. It is disheartening to think I missed something that was critical. However, I have been flying for 2 years and 190 hours without them. So, what exactly are these bolts doing that I could fly for so long without consequences? As far as I can observe there have been no adverse effects of flying without them in my case. Any comments about their functionality is appreciated.
 
Bolts are part of the margin...

The vertical bar is there to resist buckling of the web and needs to stay in place to support the spar... it is tacked there with a couple of long AN4 rivets that are probably sufficient but since the bar is likely a critical component to high wing load resistance the design calls for a couple of AN4 bolts with nutplates to ensure that it does not move.
 
RVbySDI said:
Could someone explain the functional purpose for these bolts?
Click to expand...

**** Grain O' Salt Advisory: I am not an engineer, though I do a fair handful of mechanical design and even some engineering under supervision. ****

As I understand the structure, those bolts transfer shear out of the wing spar shear webs and into the fuselage bulkhead.

Obviously, the structure seems to work adequately without them in the short term, when operated moderately. The bolts that secure the wing spar stubs to the big aluminum bars that span the cockpit, and also to the bulkheads, seem to transfer enough shear to pretty much do the job.

My guess is that engineering analysis of the structure shows that at high load factors (Gs), and after much cyclical loading, the structure might tend to fatigue and crack at the rivets and bolts that attach the spar stubs and transverse bars near the side of body. The extra bolts help distribute the shear loads more evenly into the fuselage, resulting in a structure with a greater load capacity and longer fatigue life.

Thanks, Bob K.
 
Thanks Stephen. I concluded there had to be some margin it was covering. It does seem like a large margin though when you compare the difference between the strength of AN4-13 bolts and that of a couple of driven rivets.
 
Bob Kuykendall said:
**** Grain O' Salt Advisory: I am not an engineer, though I do a fair handful of mechanical design and even some engineering under supervision. ****

As I understand the structure, those bolts transfer shear out of the wing spar shear webs and into the fuselage bulkhead.

Obviously, the structure seems to work adequately without them in the short term, when operated moderately. The bolts that secure the wing spar stubs to the big aluminum bars that span the cockpit, and also to the bulkheads, seem to transfer enough shear to pretty much do the job.

My guess is that engineering analysis of the structure shows that at high load factors (Gs), and after much cyclical loading, the structure might tend to fatigue and crack at the rivets and bolts that attach the spar stubs and transverse bars near the side of body. The extra bolts help distribute the shear loads more evenly into the fuselage, resulting in a structure with a greater load capacity and longer fatigue life.

Thanks, Bob K.
Click to expand...
This makes a lot of sense. It also may explain why my non-aerobatic 9 may not have had any issues with not having the bolts in place. I have not put much G loading on the structure in the 190 hours of flight. The closest may have been some flights in turbulence or perhaps a 1.5 pull up or something. I have definitely not put the structure in much of a high stress environment to date.
 
RVbySDI said:
This makes a lot of sense. It also may explain why my non-aerobatic 9 may not have had any issues with not having the bolts in place. I have not put much G loading on the structure in the 190 hours of flight. The closest may have been some flights in turbulence or perhaps a 1.5 pull up or something. I have definitely not put the structure in much of a high stress environment to date.
Click to expand...

If you were the installer, and you've still got the plane, presumably you flew it through Phase I. Did you not explore positive G flying traits of the airplane greater than 1.5G during Phase I?
 
airguy said:
If you were the installer, and you've still got the plane, presumably you flew it through Phase I. Did you not explore positive G flying traits of the airplane greater than 1.5G during Phase I?
Click to expand...
Well, not sure why you ask but to answer your question, NO I did not push the positive G envelope. I did push to 2.0 g's during Phase 1. However, since I have no aerobatic training and I am not a certified test pilot I was not going to push the airframe to the documented limits of the airframe. Reason being that this is a non-aerobatic airplane, I am a non-aerobatic pilot. The CG, W&B and all other aspects associated with the airframe construction were built to the kit manufacturer's standard. I have built the plane for travel purposes not for high G maneuvers. And yes, I am falling back on the engineer's documented limits of the airframe without actual testing. I am comfortable with relying on that engineering evaluation. Which, by the way, is why I was asking for the reason the engineers included these bolts in the first place when the airplane functioned without them. As I have heard many times in the past: "Margins belong to the engineer". I believe in that and will trust the engineer's margins. That goes for their margins for G loading of the airframe also. I am not going to go there just to satisfy some particular ideal of testing of a specific individual model of the general engineer's design.

So, again, I am not sure why you are asking that question but there is the answer. Whether you approve of the answer or not is a whole 'nother' question of course.

Live Long and Prosper!
 
Steve - no offense intended, and I wasn't trying to plant a barb for any reason. I was legitimately wondering if you had tested those limits during Phase I, some builders do and some don't. It's possible that if you had tested to the published limits without those bolts installed you might have discovered some spar damage as a result - that's where I was going with the question.

I agree with you that the margins belong to the engineers - and I'm not sure how far I'll pull during Phase I myself yet. I'm old enough now that pulling G's hurts more and it's not as fun as it used to be.
 
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There are many RV's flying with these bolts not installed, this SB should resolve this issue. :) Mel Asberry (DAR) has come upon this issue quite a few times and its on his list of items to check for sure during his DAR inspections.
 
RVbySDI said:
Could someone explain the functional purpose for these bolts? I pulled the seat pans out to find my spars did not have the bolts installed. And I was the installer. It is disheartening to think I missed something that was critical. However, I have been flying for 2 years and 190 hours without them. So, what exactly are these bolts doing that I could fly for so long without consequences? As far as I can observe there have been no adverse effects of flying without them in my case. Any comments about their functionality is appreciated.
Click to expand...

The bolts help re-enforce the most highly loaded area of the web of the wing spar.
Flying without the bolts installed, in and of it self, is not likely to cause any issues other than it is likely that any RV without them could not be expected to withstand the same level of G load that it was designed and tested too.
How much of a difference? That is anyone's guess, since no testing was ever done to investigate the effect of not having them installed.
 
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