Van's Air Force
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SB 14/12/06. (RV-12, F-1206F Bearing Bracket Cracks)
- Thread starter DeltaRomeo
- Start date
WingedFrog
Well Known Member
If this goes on I will have to do my annual every 6 months 
cactusman
Well Known Member
I just put my airplane back in service and now two SB's come out. Timing is everything in life.
"At or before the next annual condition inspection."
Well the way I read both SBs and the "or", you are technically good till your next annual condition inspection if you just signed this one off.
I'll probably order the wing doubler - getting ready for paint and it makes sense to do it now.
The other one you might be able to inspect with one of those camera probes from HF from the fuel pump tunnel.
The SB's are issued for free, but the parts required to do the work will cost you some money.
Rick_A
Well Known Member
I did this first half of this SB today - removal of the existing bracket. I haven't attached the tailcone to the fuselage yet, so I had good access. Getting the rivets shanks out of the bearing brackets (after I drilled off the heads) took a fair amount of force. I used the angle drill to "drill & push" the shank out of the bearing bracket.
The new parts are not showing up on Vans web order system. I don't expect them to be free but I doubt of they will be very expensive.
The new parts are not showing up on Vans web order system. I don't expect them to be free but I doubt of they will be very expensive.
Dgamble
Well Known Member
I could see the logic in not sending the parts for either of these.
Both are addressable for what is likely to be hundreds of flight hours with nothing more than a visual inspection at each annual.
I suspect that these issues are appearing on relatively high time airframes.
This is just guesswork, mind you, and with regards to free parts at least, not one I would mind being proven wrong on.
Correct.
As far as I am aware, these problems have only been detected on N412RV (the red prototype / demonstrator) with 1000+ flight hours.
Paris12Man
Well Known Member
F-1206F
My question is.... is the replacement part F-1206F better/stronger than the original part F-1206F we received in our fuselage kit?
My question is.... is the replacement part F-1206F better/stronger than the original part F-1206F we received in our fuselage kit?
Yes, but stronger is not the correct description. The original was strong enough but was not stiff enough so after a lot of flight hrs it can develop a crack.
That is the reason for making a different part available ( and supplying it in new kits from this point on )
Ex Bonanza Bucko
Well Known Member
Does the inspection part of this SB require removal of the gas tank and the baggage deck or can that be done easier?
EBB
EBB
Endoscope
John, what did you use to "fish" the camera into place?
Scott
John, what did you use to "fish" the camera into place?
Scott
I used a cheap endoscope to look at bracket thru rear inspection plate hole. The picture is from the rear looking forward. One of several pics. Bracket looks good. Took less than an hour. ( 709.5 hours BTW )
yankee-flyer
Well Known Member
Scope worked fine, BUT
I spent the better part of an hour looking for something like this without finding it. You go in the rearmost belly inspection panel and go aft, right? Do you have to somehow get into one of the other "compartments" outside the one you're in? John's picture looks like he has the scope pointed aft (from the inspection port) slightly down, and slightly to the pilot side. I'm looking at the belly skin when I do that. Directions please??
Wayne (lost inside the belly of my RV-12)
I spent the better part of an hour looking for something like this without finding it. You go in the rearmost belly inspection panel and go aft, right? Do you have to somehow get into one of the other "compartments" outside the one you're in? John's picture looks like he has the scope pointed aft (from the inspection port) slightly down, and slightly to the pilot side. I'm looking at the belly skin when I do that. Directions please??
Wayne (lost inside the belly of my RV-12)
Try to help - -
As Brad said, tape camera to a piece of fairly firm wire. Bend a 160 degree bend near the end so the camera is nearly looking back at you. Once inserted up thru rear-most inspection port and run up thru center section, you can twist as need to look as though you were in the rear looking forward toward the bracket in question. Takes a little time to bend wire and twist to get shots you want. Works. You can get this little camera into almost any part of the plane to see things. For $20 or so, handy to have around.
As Brad said, tape camera to a piece of fairly firm wire. Bend a 160 degree bend near the end so the camera is nearly looking back at you. Once inserted up thru rear-most inspection port and run up thru center section, you can twist as need to look as though you were in the rear looking forward toward the bracket in question. Takes a little time to bend wire and twist to get shots you want. Works. You can get this little camera into almost any part of the plane to see things. For $20 or so, handy to have around.
yankee-flyer
Well Known Member
Thanks-- I'll try that
Does indeed look very useful. We're already wishing we'd had one several years ago.
Wayne
Does indeed look very useful. We're already wishing we'd had one several years ago.
Wayne
sooooooo, has anyone made this replacement? i am at a point building that it is assembled but the fuse. is not attached to the tail. the bracket is right there but forward rivets [i think] don't allow an angle drill a 90 deg. shot and most builders probably have the factory head against the bearing containment. this is a 1/4'' of alum to drill thru or pound a rivet out of. i don't picture myself pulling this one off without at the very least also replacing the parts containing the bearing and probably adding doublers onto the ribs where i have ruined the rivet holes. am i just seeing doom where it isn't. i thought i would just do this now as it will never be easier but this looks like a lot of material at risk.
Dgamble
Well Known Member
If the between-the-lines question here is whether or not you should fix it now, consider that doing it now will relieve you of an annual requirement to find a way to get back in there and look at, a task you will likely approach with fingers crossed because changing it years from now is going to be far more difficult.
It doesn't do away with the inspection requirement.
This area should be inspected during every condition inspection in accordance with FAR 43 appendix D (as required by your operating limitations) regardless of whether the modification prescribed in SB 14-12-06 has been done or not.
When a S.B says inspect until the modification has been made, it is an attempt to direct a person to pay special attention to an area so that something doesn't get missed. Making the modification complies with Van's recommendation, but it does not relieve the inspector of complying with the FAA's requirements.
But I do agree you may as well do it now though. You will never have better access.....
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I am exactly where you are and I have purchased the parts to do the job. But, I have not looked at what it will take to do the work. I hope it will not be as complex as you think it will be.
Regardless, it will never be easier so I will do it now.
skydiverlv
Well Known Member
I just received the back ordered SB kit today. I removed the affected parts about three weeks ago with no issues. The procedure took less than 30 minutes to complete. I have the tank out and the rear bulkhead removed, although this operation could be performed with the bulkhead in place. Fortunately, the LP4-3 rivets I originally installed had the shop head accessible from the tunnel area. The 90 air drill I used has 1/4" center of bit to edge of tool dimension. You will need a tool like this to get to 2 of the rivets with precision if performing from the top side. Tap the mandrel out, use a #40 pilot bit, and drill out with #30 bit.
I received the parts and started the repair. It was easy until I got to setting the AN rivets, I could not figure out how to get them set. I called Vans and got a CR blind rivet replacement option which seems like it will be easier. Any hint on how to set those AN rivets in that confined space?
skydiverlv
Well Known Member
I plan to install the SB this afternoon. From what I remember, my plan was to squeeze the AN rivets then install the assembly in one unit with the included pull rivets. Is that not possible? I am not at home right now to inspect.
Dgamble
Well Known Member
Ah, interesting.
Does it change anything with regards to the log books? IOW, would I make an explicit logbook entry for "C/W annual inspection req. SB 14-12-06" or similar for the periods prior to making the physical changes, then revert to the all-inclusive "deemed airworthy" type of wording after? Or is it just assumed with the latter entry regardless of whether I've used the replacement parts?
Rick_A
Well Known Member
I did mine this past week and that's how I did it. Riveted the angles to the bracket and then installed it.
It was not easy installing the new bracket. It is much stiffer than the old one and was a very tight fit. My tailcone is not attached, so I had easy access. As I was installing the bracket, I was thanking my lucky stars that I didn't have to do this on a finished airplane.
Rick_A
Well Known Member
Step 7 says: Rivet the new Brace to the Angles. I left out a few word and part numbers.
It would be more clear if it said Rivet the Angles to the Brace - even though the meaning is the same.
Step 8 then has you cleco the new Brace/Angle assembly to the bulkhead and ribs.
It would be more clear if it said Rivet the Angles to the Brace - even though the meaning is the same.
Step 8 then has you cleco the new Brace/Angle assembly to the bulkhead and ribs.
The procedure calls for the angles to be riveted to the brace, before installing and riveting the brace assembly into the fuselage.
Insertion tip - the boxed area the brace installs in is wider at the bottom. Positioning the brace to the bottom and then moving it upward into place will make the process easier.
Hit Nail on Head
Jim D
Spot on. If I'd done that the task would have ben much easier.
Jim D
For an experimental, all that is required to be in your log book is an entry worded to match the requirement dictated by your operating limitations.
If you own an S-LSA RV-12, it would be in your best interest (more specifically a mechanic signing his name to the log book for a condition inspection) to specifically reference compliance to the S.B. by inspection or installation of the new parts.
SB 14/12/06 Experiences
My inspection of F-1206F IAW SB 14-12-06 showed a crack in the right side flange around the rivet very similar to what was shown in the SB. I found an additional crack about 3/8 inches long starting in the brace area at the aft right outboard edge of the part. I submitted a RV-12 Feedback Form to Van?s Engineering last week with a photo showing the cracks. Total time on my RV-12 at the inspection was 224.4 hours.
It took a helper and I about 3 hours to remove the bearing bracket brace. It was very difficult to drive the rivet mandrels out of the bearing bracket assembly. To get enough room to swing the hammer, I cut off the shank of a #40 drill and held it with small vice grips. Due to the thickness of the bearing bracket assembly it took a lot of force to drive the mandrels out. Then the rivet would spin when I tried to drill the manufactured head and there wasn't enough of the shop head to grab with pliers or dikes. I then had to cut out a part of the bearing bracket brace because it was 2" wide and I only had a 1" angle drill. The manufactured heads for the forward flange rivets were on the aft side so we had to use a mirror to make sure we were in the center of the manufactured head before drilling. Once the head was removed it was easy to grab the shop head and pull out the remaining part of the rivet. There was plenty of shop head to grab since the flange and sheet metal was thin.
I riveted the new brace to the angles using the solid rivets outside the aircraft. I don?t see how you can squeeze the solid rivets with the angles installed in the airplane. Getting the assembled angles and brace into position to rivet was another interesting experience because you have rivet shop heads above and below where the bracket assembly needs to go. I agree with whoever said start with the assembly at the bottom channel and then try to move it into position. After an hour or so of trying every angle and orientation possible the assembly will mysteriously jump over the shop heads and into place. Final riveting of the bracket assembly into place is pretty anticlimactic. Bob Kibby N712BK
My inspection of F-1206F IAW SB 14-12-06 showed a crack in the right side flange around the rivet very similar to what was shown in the SB. I found an additional crack about 3/8 inches long starting in the brace area at the aft right outboard edge of the part. I submitted a RV-12 Feedback Form to Van?s Engineering last week with a photo showing the cracks. Total time on my RV-12 at the inspection was 224.4 hours.
It took a helper and I about 3 hours to remove the bearing bracket brace. It was very difficult to drive the rivet mandrels out of the bearing bracket assembly. To get enough room to swing the hammer, I cut off the shank of a #40 drill and held it with small vice grips. Due to the thickness of the bearing bracket assembly it took a lot of force to drive the mandrels out. Then the rivet would spin when I tried to drill the manufactured head and there wasn't enough of the shop head to grab with pliers or dikes. I then had to cut out a part of the bearing bracket brace because it was 2" wide and I only had a 1" angle drill. The manufactured heads for the forward flange rivets were on the aft side so we had to use a mirror to make sure we were in the center of the manufactured head before drilling. Once the head was removed it was easy to grab the shop head and pull out the remaining part of the rivet. There was plenty of shop head to grab since the flange and sheet metal was thin.
I riveted the new brace to the angles using the solid rivets outside the aircraft. I don?t see how you can squeeze the solid rivets with the angles installed in the airplane. Getting the assembled angles and brace into position to rivet was another interesting experience because you have rivet shop heads above and below where the bracket assembly needs to go. I agree with whoever said start with the assembly at the bottom channel and then try to move it into position. After an hour or so of trying every angle and orientation possible the assembly will mysteriously jump over the shop heads and into place. Final riveting of the bracket assembly into place is pretty anticlimactic. Bob Kibby N712BK
PilotBrent
Well Known Member
224 hours!
I thought Scott mentioned that the factory -12 had over 1000 hours on it before these cracks were identified. 224 hours doesn't seem like very long - definitely gets one's attention. Would you mind sharing the picture(s)?
I thought Scott mentioned that the factory -12 had over 1000 hours on it before these cracks were identified. 224 hours doesn't seem like very long - definitely gets one's attention. Would you mind sharing the picture(s)?
N712BK Bracket Cracks
I am unable to post attachments on this forum. It has been so long since I posted photos I don't remember the process. Send me a private e-mail with you e-mail address and I'll e-mail you the photo. Since I sent the photo to Van's, Scott may be able to post it. Bob Kibby N712BK
I am unable to post attachments on this forum. It has been so long since I posted photos I don't remember the process. Send me a private e-mail with you e-mail address and I'll e-mail you the photo. Since I sent the photo to Van's, Scott may be able to post it. Bob Kibby N712BK
PilotBrent
Well Known Member
waterboy2110
Well Known Member
Yikes! I bought the kit and wasn't looking forward to drilling those rivets out but after this the part will go in this weekend. I don't have the tail cone on so it's accessible. For driving mandrels or solid rivets out I use an auto punch with the theory that the G force applied is a much shorter, high G spike as opposed to a long duration (lot's of energy under the curve) pulse from a hammer and punch. Works very well for me.
Install tip......
For those that have the rivets installed so that the shop head is on the bracket flange..... (as shown in the photo)
Use a dremel type tool to grind the shop heads off of the rivets. It doesn't matter if you grind into the flange material of the bracket because it will be discarded. Once the heads have been ground flush to the flange, it should not be too difficult to get the bracket out (you could even cut it into two pieces using the dremel tool) and then remove the remainder of the rivets.
For those that have the rivets installed so that the shop head is on the bracket flange..... (as shown in the photo)
Use a dremel type tool to grind the shop heads off of the rivets. It doesn't matter if you grind into the flange material of the bracket because it will be discarded. Once the heads have been ground flush to the flange, it should not be too difficult to get the bracket out (you could even cut it into two pieces using the dremel tool) and then remove the remainder of the rivets.
12vaitor
Well Known Member
I had the same issue with squeezing the solid rivets to make the assembly before installing it. It took about 5 minutes to figure out there was no way it was going in as an assembly. I ended up removing the top two rivets on one of the bearing brackets to get the clearance needed to get the brace assembly positioned.
John Salak
RV-12 N896HS
I guarantee that it can be done, or the install document (which was confirmed while a test installation was done on the RV-12 prototype) would have been written differently.
As mentioned previously, the space is a little wider at the bottom, and the two ribs are slightly flexible at the back.
