SB 14-01-31; RV-6, 7, 8

[ChiefPilot]

RV-6A
First flight Nov 2012
208 hours
IO-360-B1B w/Pmags
Hartzell BA CS
(Very) occasional grass
Lots of aerobatics, frequently to 4g
No notches
No cracks

[pvalovich]

Did both inspections yesterday - no cracks.

Inyokern CA (IYK)
IO-360 180 HP - 1 mag;1 Lightspeed Ignition
391 Hrs Total Time in 2 1/2 years
Never been on grass
Try to pull at least 3 g's and go upside down every solo flight (one of the benies of flying in the middle of nowhere)

[McDoogle]

RV-6
Tail built 1988
First flight 2012
Total time. 125
Lyc 0-360
Hartzell CS
No Acro
Some grass
No notches
No cracks


Doug McMullin
RV-6. N262DM
Ottawa, Ks

[dabney]

RV6A
First flight 8-20-97
total time 1731 hours
Not builder
Last 500 hours since I have owned a/c no acro, no grass, no dirt
Previous usage unknown
O-360 A1A
Hartzell Contant Speed Prop

No notches
No cracks after careful inspection both SB's

[penguin]

RV-6A
First flight 2000
Total time 800
Lyc 0-320
Sensenich FP
Lots of acro and formation
Lots of grass in the last 7 years, occasional before that
No notches
No cracks in tailplane or elevator
A couple of slightly loose jam nuts (1/8 turn max)

Pete

[Steve RV7]

This is my first post to the VAF website and the RV community since purchasing a flying RV-7 in March of 2013. After inspection using a magnifying borescope, and with the gracious help and critical eyes of my friends at Parkside Airpark (WA87), RV builders Jon Friedemann and Dan Miller, I can report that we found no cracks in either of the separate areas specifically referred to in Van?s Service Bulletin numbers 14-01-31 and 14-02-05. Following is information on my airplane for the database being developed for these SB?s.

RV-7 completed in 2008
Non-builder 2nd owner, purchased in March 2013
IO-360 EXP, 210 HP
Hartzell Blended Airfoil CS prop
369 hours TT as of February 2014
Mild acro <4 G's
Often push back on HS
Primarily operated on paved runways
Has relief notches
No cracks, both SB's

[Mike S]

This is my first post to the VAF website and the RV community since purchasing a flying RV-7 in March of 2013.

Steve, welcome aboard the good ship VAF:D:D

[JonJay]

This is my first post to the VAF website and the RV community since purchasing a flying RV-7 in March of 2013. After inspection using a magnifying borescope, and with the gracious help and critical eyes of my friends at Parkside Airpark (WA87), RV builders Jon Friedemann and Dan Miller, I can report that we found no cracks in either of the separate areas specifically referred to in Van?s Service Bulletin numbers 14-01-31 and 14-02-05. Following is information on my airplane for the database being developed for these SB?s.

RV-7 completed in 2008
Non-builder 2nd owner, purchased in March 2013
IO-360 EXP, 210 HP
Hartzell Blended Airfoil CS prop
369 hours TT as of February 2014
Mild acro <4 G's
Often push back on HS
Primarily operated on paved runways
Has relief notches
No cracks, both SB's

I would also note that this was done with paint removed and a high power boroscope that allows you to examine the edge of the relief notch, not just the surface of the sheet.
I think careful inspection might mean different things to different people. I would hazard a guess that many who reported no cracks are simply not seeing an obvious crack and moving on. Walt warned of this earlier in this thread, but with hundreds of posts, things get lost....
At this level of inspection, even if a crack is found, is it the type of crack the SB is all about? Was it caused by stress or fatigue?
Drill a few holes in some .032 material, examine the edge of them under high power magnification and tell me you won't find a crack here or there. T3 temper is quite brittle.

[Paul 5r4]

N729PG RV7A
No cracks
Notched
No acro
Paved runways only
180 hrs TTSN (first flight 1 April 2012)
Lycomong 0 320 D1A
Sensenich FP prop

[Pilot Dog Ship]

Maybe we should also be asking how much up-elevator deflection pilots are holding during taxi and especially during the engine run-up.
Those of us with mirrors for use when flying formation and dogfighting can also observe how the horizontal stabilizer dances at high power settings on the ground when the elevator is deflected up.
IIRC, Cessna had problems with their 210 stabilizers cracking and the cause was traced to high-power settings on the ground.
My Dog Ship has 660 hours, modest acro and formation but twenty-six pilots have transitioned into tailwheel in it so it has seen more than its share of rough handling plus it has been on its back once.
O-320, Sensenich FP, one tiny, very-new looking crack on upper right-hand corner of stabilizer front spar, no notches.
Have been running engine at full-power on the ground several times in the last month while troubleshooting other issues.
Service kit has arrived, may hold off installing it to see what the Engineers at Van's come up with.

[Richard Connell]

RV-7 S/N 72555
Completed AUG 2009
400 TT
IO-360-M1
Hartzell BA
Lots of grass.
Lots of short rough strips.
Some Mild Acro
Notches per plans - I remember doing a second set of front spars as wasn't happy with the first notches circa 2005.

[dabney]

"I would hazard a guess that many who reported no cracks are simply not seeing an obvious crack and moving on."

This comment was made a couple of replies ago.

Really?

I do not agree with your hazardous guess. I think RV owners after reading the extensive comments on this subject know where to look, how to look, what to do to prepare the surface for inspection etc, particularly after some earlier comments that some of the early inspections did not detect a "not so obvious" crack. Many owners are bringing an extra set of eyes into the inspection process, photos, magnification, borescopes etc to ensure any "not so obvious" cracks are not missed.

My a/c luckily did not have any cracks but I could post the pictures I took to prove it, if I knew how.

[JonJay]

"I would hazard a guess that many who reported no cracks are simply not seeing an obvious crack and moving on."

This comment was made a couple of replies ago.

Really?

I do not agree with your hazardous guess. I think RV owners after reading the extensive comments on this subject know where to look, how to look, what to do to prepare the surface for inspection etc, particularly after some earlier comments that some of the early inspections did not detect a "not so obvious" crack. Many owners are bringing an extra set of eyes into the inspection process, photos, magnification, borescopes etc to ensure any "not so obvious" cracks are not missed.

My a/c luckily did not have any cracks but I could post the pictures I took to prove it, if I knew how.

Yes - really. This comment came after I assisted in an inspection AFTER, they had already reported "no cracks". They are removing the paint now to re-inspect. I do not expect them to find anything..... their build is top notch.
I did not "hazard" a guess, so I should not have worded it as such, and I should not have said "many". I certainly did not mean to offend you or anybody else.
From my past experiences, RV owners are not much different than anybody else, and with the long, long posting, it would be very easy to miss the prior comments you mentioned.
If my comments send one person back to inspect and that one person finds something different, it was worth reminding people.

[n747jg]

N747JG RV-8
No cracks (close-up HiRes photos)
No notches
Mild acro, less than 4 g's
Paved runways
590 hrs TT (first flight July 2008)
Lycoming (Barrett) I0-360-X 215 hp 10.1 pistons
Dual P-Mags
WhirlWind 200RV CS prop - professionally balanced

Regularly back the airplane and steer into the hangar using the empennage

Jim Gray
www.rmrairshows.com

[RV3bpilot]

I had a twisted aileron and tried to drill out the rivets to save the skeleton but after a few rivet holes enlarged I threw it all in the scrap aluminum pile in the corner and ordered a complete new aileron kit. I do feel for you all who find the cracks in the H.S. parts. I felt the worst part was re-painting.:(

[bret]

I have no cracks....or flt hrs, still under construction, but still, I drilled mine all apart this weekend and waiting for the parts to come in. No rivet holes were harmed. 4 Hrs

[kblack]

Building a 7. And I am the 3rd owner of a 6 purchased last summer with about 1,000 hours. My understanding is the builder worked for Gulfstream and used their paint system. Beautiful craftsmanship and paint (very tough) throughout - including on the parts that require inspection.

I was stumped on how to proceed, but posts to this thread clued me in. Planning to use Methylene Chloride based stripper (nasty, but won't harm aluminum), Q-tips, and plastic or wooden scrapers to remove the paint for a proper inspection with a magnifier or camera (borescope). I will report back with results.

Kudos to Van's for their quick follow up to develop and publish these SB's. And a special thanks to RVBuilder2002 (Scott) for his hard work to keep up with this forum, and for his patient and thorough answers to the sometimes "tedious" questions and comments. Keep up the good work!

While I'm at it, I can't say enough about this website and these forums. Way to go Doug Reeves for having the vision, skills, and tenacity to make it happen!

[dilamipo]

I-RVBL RV-7
No cracks
notches as plan
Mild acro
Paved runways 10% , Grass 90%
110 hrs TT (first flight April 2013)
Lycoming 0-360-A1a
Hartzel-Tonini CS prop - professionally balanced

Regularly back the airplane and steer into the hangar using the empennage

[Robski]

Regularly back the airplane and steer into the hangar using the empennage
Well stop it, then! :D

Use the tailwheel / spring, either in your mitt (I do) or via a tow bar!
The spring is designed to take the weight of the aircraft, in side loads as well as vertical ones.

Just because RVs are tough as old boots there's no need to treat one like an old boot!

[49clipper]

No notches, no cracks, 325.0 hrs/light acro, less than 3.5 g's, RV-6, O-320,
90% grass.

so what is the tally so far on cracks?

[wrongway john]

Quite a long thread, and have only went through half of it thus far. The SB states to ?Clean the area and remove any paint, overspray or primer that could hide a crack.? The pic that Van uses in the SB shows the crack without them removing the primer. Also noticed quite a few taking pics stating no cracks found, which didn?t bother to remove paint/primer either.

[magiccarpet]

I don't understand why enlarging the forward top most holes of the flanges of HS-405 from #40 to #27 in step nr. 13 of the SB.
Those holes aren't anymore for any good after the SB fix, are they? I can't see from the drawings.
I rather don't want to enlarge them, 'cause they are already a tiny bit out of MED tolerance.
The most obvious reason I can imagine of, is to eliminate the 3/32 dimple around that holes. But why bother?

any ideas on that?

I probably should add that I haven't riveted the skin on the HS yet. Lucky me :rolleyes: .So maybe that is why I don't understand the reason for step 13 yet.

[rvbuilder2002]

I don't understand why enlarging the forward top most holes of the flanges of HS-405 from #40 to #27 in step nr. 13 of the SB.
Those holes aren't anymore for any good after the SB fix, are they? I can't see from the drawings.
I rather don't want to enlarge them, 'cause they are already a tiny bit out of MED tolerance.
The most obvious reason I can imagine of, is to eliminate the 3/32 dimple around that holes. But why bother?

any ideas on that?

I probably should add that I haven't riveted the skin on the HS yet. Lucky me :rolleyes: .So maybe that is why I don't understand the reason for step 13 yet.
After the inboard spar flange gets trimmed, there is a gap between the rib and the skin at the location of this hole. If a rivet is installed as is, it can suck the skin inward and the rib outward. Undesirable for both.
Structurally there is very little benefit having them riveted together, so the hole gets enlarged to allow filling the skin hole with a rivet, but not attach it to the rib.

[Geico266]

255 Hours
No cracks
No notches

Mild acro
Grass 40%

IO-360 195 HP
Constant speed

[magiccarpet]

After the inboard spar flange gets trimmed, there is a gap between the rib and the skin at the location of this hole. If a rivet is installed as is, it can suck the skin inward and the rib outward. Undesirable for both.
Structurally there is very little benefit having them riveted together, so the hole gets enlarged to allow filling the skin hole with a rivet, but not attach it to the rib.

That makes perfect sense. Thanks a lot for your explanation

[ao.frog]

RV-7 290 hrs
Notches per plans
No cracks

75 % pavement
20 % grass
5 % snow-covered ice rwy's

Lots of std acro maneuvers (max +4)
Lots of formation

10 % at MTOW

Superior IO-360
MT C/S prop dynamically balanced

Moved with towbar on TW

[B Cunningham]

RV7 225 hours
No cracks
Builder # 71313
Notches per the plans dimensions
Mild acro
-5% grass
Always pushed around with the empennage. :mad: I'm changing that habit...

[tracy]

After the inboard spar flange gets trimmed, there is a gap between the rib and the skin at the location of this hole. If a rivet is installed as is, it can suck the skin inward and the rib outward. Undesirable for both.
Structurally there is very little benefit having them riveted together, so the hole gets enlarged to allow filling the skin hole with a rivet, but not attach it to the rib.

Could you just use the cut out flange piece and use it for a spacer with a rivet?

[Mark Burns]

Could you just use the cut out flange piece and use it for a spacer with a rivet?

You obviously haven't cut your flanges off yet :-)
They are not pretty. I needed a right angle dremmel.

And you're not really complying with the SB if you add your own twist.
Minor as it may be, it wouldn't fly in the certified world. No pun intended.

Mark

[bret]

Called Vans this morning inquiring about the repair kit. Apparently they sold out of the first batch pretty quick. Next week they should have the next batch ready to ship out she said. Just curious how many folk are doing the mod?

[akarmy]

Yep, I ordered the kit, like you Bret I'm going to do the mod to my finished but unmounted HS. I figure if it gets too messed up I can build another one before I match drill it to the fuselage!

[Snowflake]

I was going to order one and then heard that they had stopped shipping them because Van's engineers were putting their heads together... Sounded like there may be a change coming. Maybe Scott can comment whether that is true or not? If not, i'll be ordering the kit pretty quickly.

[Pilot Dog Ship]

It was post #319 that I may have mis-interpreted.
I read it as there might be a different type of fix coming down the pipe from Engineering...

[bret]

I was going to order one and then heard that they had stopped shipping them because Van's engineers were putting their heads together... Sounded like there may be a change coming. Maybe Scott can comment whether that is true or not? If not, i'll be ordering the kit pretty quickly.

Hum...no word of a .....change order for the mod, just a delay of getting the next BATCH out?

[Bavafa]

Hum...no word of a .....change order for the mod, just a delay of getting the next BATCH out?

I talked to them and asked if there maybe another solution than already exist. They told me that there is no other engineering work is being done other than including this part into the regular kit.

[tracy]

I was thinking the same thing. My spar web looks the same as in the picture above. No notches per MY plans (dated Feb 28/01). Instructions say to "trim to fit"

Bevan

My older kit has the same narrow spar web as shown in my previous pic. Hopefully this will avoid any future cracks!

[Snowflake]

It was post #319 that I may have mis-interpreted.
I read it as there might be a different type of fix coming down the pipe from Engineering...
I read it that way too, but it sounds from later posts like the current one is the only fix though, so I'll get over to Vans and order the kit.

[330drvr]

RV-7A
500 hours
Notches yes
Cracks no

IO-360
2 blade aluminum C/S MT (now replaced by 3 blade MT)
mild aero
paved runways

[Jim Wright]

RV-8A N698BS
470 hours
No Notches, No Cracks.
IO-360
2 blade aluminum C/S MT
No aero
Almost exclusively paved runways

:D

[BillFear]

RV7a
915 hours
0-360 with 2 Blade hartzel CS
No notches
Very little acro
Very little grass strip

No cracks, HS or Elevator spar

[Kevin Horton]

RV-8 C-GNHK Ser # 80427
280 hours
No notches, no cracks
IO-360-A1B6 with 3 blade MT prop
Used almost exclusively on paved runways, with very occasional grass strips.
Occasional aerobatics.

[gerrychuck]

Inspected hangar partner's aircraft today:

RV8 C-GLZR Bald Eagle
Completed 2007
300 hours
O-360
Sensenich FP
Moderate positive G acro
Mostly pavement
No notches
No cracks

[dromuald]

RV-8 655CL
450 TT
IO-360A1B6
Hartzell C/S

Go upside down or a loop almost every flight
Std acro up to 4 G
Mostly paved but 5% grass
almost always use tow bar

no notches
no cracks - stab or elevator :)

[JimWoo50]

RV-6 kit no. 22300
147 hrs
Very limited grass rwy ops lots of bounces on pavement though.
O-320 fp Sensenich
No notches
No cracks anywhere.

[DanH]

I earlier asked what methods folks were using to remove the paint for inspection.

Mine is PPG epoxy primer, base, and DCU clear, which is pretty tough. What worked was rolling a strip of rag about 1" wide into a roll about the diameter of a cigarette butt. Soaked it with MEK, stuffed it into the corner, put a piece of aluminum tape over it, and came back in 15~20 minutes. Worked well; the trapped vapor and long soak time made a nice soft patch of paint which came right off with just a little rubbing. MEK isn't going to cause a corrosion issue later.

For the next one I'll try a cotton ball.

http://i57.tinypic.com/35a16k9.jpg

I had looked last week with paint in place and found nothing. With the paint removed I spotted what looked like a crack to the naked eye. However, it is worth grabbing a camera...a high-resolution photo says no:

http://i60.tinypic.com/2rfvhgz.jpg

RV-8
325 hrs
390, Hartzell CS
acro, grass
no notches
no cracks

[bret]

Thanks Dan, I did not think that MEK would eat through clear! I best keep that stuff away from my paint job.

[estoro]

Latest Vans answers.
As of this morning 17 Feb, send time for the -8 kit is "one week". Also talked to a tech rep; "There is no additional fix in the making". 'Can not see advantage to using blind rivets'.
I used 2 hrs to dismantle the tail. Vans tech rep says 8-10hrs to make mod. I guess 4 hours to reinstall.

RV-8, #620
550 hrs over 13 years
Gentlemans aerobatics
Hard surface, 190HP C.S. prop
One small crack upper right corner, no reliefs.

Cheers,
Ed


.

[LeMar]

RV-7
O-360
Hartzell CS
Finished in 2003
800 hours
No cracks

[Lote]

Completed second SB inspection on elevator spar and no cracks found. IMHO, for aluminum to crack it has to flex, and for these parts to flex, either the elevator hinge line must not be dead straight, or some heavy loads are moving the stabilizer tips up and down, or both things in combination are happening. For those who found cracks in either spar, I wonder if viewing down their hinge holes they are perfectly concentric.

LeRoy Johnston, Ohio

RV-6A
O-360, 180HP
Hartzell
SN 25764, first flew 2006
765 Hrs TT
No acro
99 percent on pavement
No cracks, no notch on first SB inspection

[avpro56]

RV-80094
705 Hours TT
No relief holes
No cracks in HS or Elevator Spars
50% grass /pavement occasional aerobatics

[jim plaster]

Just inspected two Aircraft today.....rv6a,685 hours ttaf,io360 200 hp ,hartzell c/s prop. Kit completed in 2001, does have relief radius.....no cracks....airplane #2... Rv8..100 hours ttaf,o320 160 hp, sensenich f/p prop....kit completed 2002..has relief radius...no cracks. Also inspected elevator spars for cracks in hinge areas.....none found on either aircraft.....mild aerobatics of less than 3.5 g on both ships

[estoro]

Okay everyone, we got the message on the crack-relief-flying off carriers etc.
Now what is really needed is more info on how to do the fix. Bret, Mark, 2000, have all been very helpful. But please ---more photos with explanations.
Bret, did you drill out/off the skin at the rear spar?? Mark, how did you buck the fish mouth area rivets?? Difficult? easy?? How much time? Right hand-left hand-blind rivets???

If you plan on selling your airplane, how will you answer the "Stab Spar Mod" question. (no mod? subtract $2000).

Thanks

Ed (waiting on parts)

[Norman CYYJ]

Another area that should be checked while doing the SB is to look at the rudder for the same cracks that might appear on the elevator. The rudder is also supported as the elevator is and loose jam nuts could cause cracks at the rivets that fasten the nut plates.

[Frank Smidler]

Finally made it through the snow to the hanger. Inspection made with paint in place, no indication of anything to worry about. Will strip paint when temps warm up enough and inspect more closely. Don't believe pushing on tail to move would cause a stress crack that requires high cycles (not nearly enough cycles).

RV-6
O-360, 180HP
Wood Sterba
First flew 2009
550 Hrs TT
Minimal acro
50% grass
ALWAYS push plane into hanger with horizontal Stab
No cracks, minimum notch

[Mark Burns]

Okay everyone, we got the message on the crack-relief-flying off carriers etc.
Now what is really needed is more info on how to do the fix. Bret, Mark, 2000, have all been very helpful. But please ---more photos with explanations.
Bret, did you drill out/off the skin at the rear spar?? Mark, how did you buck the fish mouth area rivets?? Difficult? easy?? How much time? Right hand-left hand-blind rivets???

If you plan on selling your airplane, how will you answer the "Stab Spar Mod" question. (no mod? subtract $2000).

Thanks

Ed (waiting on parts)


Ed,
I think we've all been too busy installing the kit!

The hardest part is drilling/punching out those rivets on the ends of the angles.
I used an angle drill.

The riveting turned out to be a "non-issue" for me.
Up in the tight spots I used a 3X gun with a short (3") offset rivet set.
Take the spring off the gun, there's no room for it.
Turn the rivet set for each rivet to line it up with the gun in an optimum position to hold well. Tape the rivet set to the gun with electrical tape to keep it from rotating while riveting.

Nearly every rivet requires a repositioning of the set and tape it again.
I ran the air pressure on 60 but I'm sure some 3X guns are different.

It is quite a project. More than the few evenings I had estimated. I just reinstalled the empennage back on my 7A tonight.
I plan to fly tomorrow, it's been a long time!

As to how will I answer the "Stab Spar Mod" question. I will simply tell the truth. That I had two cracks and complied with the SB by installing the Vans kit.

Good luck with yours. Just take it slow and easy on the ones that are hard to get to.

Mark





http://i1133.photobucket.com/albums/m599/mabbmbcb/20140215_183112.jpg

[jim plaster]

Looks like Mark has the best idea by removing the root ribs for access. This would give more access to drill and shoot the rivets thru the spar web. Not to mention minimizing damage should the rivet set jump off and trash the spar web. I'd plan for a week of down time to do the mod based on 34 years of sheet metal experience.

[uk_figs]

RV-7
O-360, 180HP
Catto 3 blade
First flew Oct 2008
300 Hrs TT
Occasional acro
50% grass
Push plane with horizontal Stab
No cracks, notched

[Mark Burns]

Looks like Mark has the best idea by removing the root ribs for access. This would give more access to drill and shoot the rivets thru the spar web. Not to mention minimizing damage should the rivet set jump off and trash the spar web. I'd plan for a week of down time to do the mod based on 34 years of sheet metal experience.

Hi Jim,
Removing the ribs is not "my idea".
It's called out in the Service Bulletin.
And it would be impossible to do without removing the ribs.

Just didn't want to take credit for the idea.
Good luck with yours.

Mark

[jim plaster]

Looks like the best option ....I've heard there's possibly a new rib in the works to allow for the doubler thickness without cutting the leg off? Sure would make it a cleaner mod. Any interest for non- builders on having this mod done for you?

[flytoboat]

RV6A
0-320/Sensenich F/P
Finished 2001
260 hours
No aerobatics (yet)
No unpaved runways (yet)
No relief notches
No cracks on HS or elevator
No action until next condition inspection

[bullojm1]

RV-7
IO-360/Whirlwind C/S 200RV
Finished 2010
180 hours
Light aerobatics (3.5G's max)
No unpaved runways
Relief notches
No cracks on HS or elevator

[Walt]

Looks like the best option ....I've heard there's possibly a new rib in the works to allow for the doubler thickness without cutting the leg off? Sure would make it a cleaner mod. Any interest for non- builders on having this mod done for you?

I have ordered a half dozen kits (which I am still waiting on) and am currently tooling up for the repair work. I don't like being the first in line for something like this, gives me a chance sit back and learn from everyone elses mistakes :D

[WenEng]

26 failures in 241 aircraft so far.
Call it 10 % failure rate. (a meaningless number with only 241 aircraft reporting)
I suppose this post is therefore meaningless too.. :D

RV6 - 8/86. 9%
RV7 - 11/72 15%
RV8 - 7/69 10%
Unspecified - 0/14

Others can summarize failure details for some patterns. I don't see one. But then, I've always been a big picture guy...

[Bavafa]

Looks like the best option ....I've heard there's possibly a new rib in the works to allow for the doubler thickness without cutting the leg off? Sure would make it a cleaner mod. Any interest for non- builders on having this mod done for you?

Considering that the new rib is not dimpled but the skin is, it would be hard to get them joined well to match drill them.

[Kentsrv7a]

RV-7A
IO-360/Hartzell Blended Airfoil C/S
Finished Nov 2011
190 hours
Occassional Light aerobatics (3.0G's max)
No unpaved runways
Relief notches
No cracks on HS or elevator

[JonJay]

26 failures in 241 aircraft so far.
Call it 10 % failure rate. (a meaningless number with only 241 aircraft reporting)
I suppose this post is therefore meaningless too.. :D

RV6 - 8/86. 9%
RV7 - 11/72 15%
RV8 - 7/69 10%
Unspecified - 0/14

Others can summarize failure details for some patterns. I don't see one. But then, I've always been a big picture guy...

Sadly, there will be a lot of aircraft out there that not only don't visit VAF, they don't even look for SB's. There are still rudder failures reported from time to time as an example.

[estoro]

Everyone.....if you are on this page, you are in the wrong place! Go to "SB 01-31-14 Completed" by RV8iator, #8 (search??)

It has a dozen pictures of the Van's mod. EXCELLENT information. Add the notes by Mark (riveting the 'inside' rivets), and the note about punching out the rivets with a 'nut on a bucking bar', and life will once again become good!

Ed

[bret]

This is bugging me, what is flexing to cause the crack in the first place? HS 710 and HS 714 are made out of 6061 and the spar is 2024 right? is'nt 6061 more brittle than 2024? you would think if they were riveted together, and they are, that the angles would crack first? then what if the crack then moves out to the end of the angles with the mod installed, will we need a bore scope to inspect.....ok , my brain hurts, I better get back to work.

[plehrke]

This is bugging me, what is flexing to cause the crack in the first place?

No flexing is required for cracks to form. Flexing contributes to fatigue cracks. Per discussion in this thread, the failure is a strength issue, not fatigue. The sheer load carried in the webs encounters a place where the load may not flow well around the corner. This causes local stresses to surpass the limit load for the web and the material cracks.

[bret]

Not trying to start an argument, just trying to learn from others. I can not comprehend how a crack can form without any movement. But here is a quote from another thread from someone who knows these aircraft;

(As I mentioned in another thread, the implementation of the S.B. wasn't because the horizontal stab was found to have a weak point (it was static tested and handles the limit and ultimate loads just fine), it was because with time in service it has ben found to have a slightly more flexible point that in some cases was inducing a fatigue crack. Structural strength and structural longevity are two totally different design aspects.)

[pierre smith]

Air Tractor had a wing fail about 15 years ago, despite testing to destruction at the factory, killing the pilot (in Arizona).

They had a spar splice fix designed, but the lower steel spar caps have an 8,000 hour life. Cycles often tell the story and I believe that is what we have here....that, and the fact that some pilots are easier on their airplanes than others.

Best,

[Walt]

This is bugging me, what is flexing to cause the crack in the first place? HS 710 and HS 714 are made out of 6061 and the spar is 2024 right? is'nt 6061 more brittle than 2024? you would think if they were riveted together, and they are, that the angles would crack first? then what if the crack then moves out to the end of the angles with the mod installed, will we need a bore scope to inspect.....ok , my brain hurts, I better get back to work.

If anyone thinks that aircraft structures are rigid, than that is a misconception, these things bend/twist/flex constantly, and probably much more than you may think.

[plehrke]

Not trying to start an argument, just trying to learn from others. I can not comprehend how a crack can form without any movement. But here is a quote from another thread from someone who knows these aircraft;

(As I mentioned in another thread, the implementation of the S.B. wasn't because the horizontal stab was found to have a weak point (it was static tested and handles the limit and ultimate loads just fine), it was because with time in service it has ben found to have a slightly more flexible point that in some cases was inducing a fatigue crack. Structural strength and structural longevity are two totally different design aspects.)

Missed that post and will go back and find it. I agree with Walt in previous post, everything stains some under load.

[Robert Anglin]

Guys you may be looking for post #277. I agree, and think it is very fair and up-front on this question. Thanks. Yours as always R.E.A. III #80888

[myrv6180]

Inspected my -6 today. Slow build and 700 hrs. Hundreds of rolls and few loops,mostly paved runways. NO CRACKS.

[bret]

Missed that post and will go back and find it. I agree with Walt in previous post, everything stains some under load.

The quote is not from this thread, it was one a while back in the general disc, (question if you ARE still building)

[bret]

Weeee! I have not done any rivet stuff for a while. Does this mean I might be a repeat builder in the future....hope not, can't aford this one. Just Kepp drilling drilling....swimming!

http://i895.photobucket.com/albums/ac158/bret496/DSC04461_zps57f47025.jpg

[Bavafa]

Looks good.
On other notes, I never understood the reason for trimming the spar flange which will leave on rivet on the skin that will not be riveted to the spar any more. Any thoughts on that?

[bret]

Looks good.
On other notes, I never understood the reason for trimming the spar flange which will leave on rivet on the skin that will not be riveted to the spar any more. Any thoughts on that?

I think it is so you can lift the skin to get a piece of SS between the skin and spar for trimming the corners off with a cut off wheel.

[Walt]

Looks good.
On other notes, I never understood the reason for trimming the spar flange which will leave on rivet on the skin that will not be riveted to the spar any more. Any thoughts on that?

Helps to relieve the stress concentration in the corner of the web where the cracking is occuring.

[Bavafa]

Helps to relieve the stress concentration in the corner of the web where the cracking is occuring.

Thanks Walt. I do realize I had not explained my question right but you got it.

[SilverEagle2]

Helps to relieve the stress concentration in the corner of the web where the cracking is occuring.

I was just about to ask this question as it seemed silly to cut them off. Your explanation clears it up. Thanks!

[jayjabour]

HS Spar inspection showed no cracks, took some time to remove the Paint overspray and Primer, but none seen. Relief notches per drawings.
RV-7, 200 hrs, some Acro, O-360, no cracks

[Achelis]

RV6-A
First Flight 1996
980 Hours TT
No cracks in HS or Elevator Spars
Relief per plans
Heavy Acrobatics first 25 hours / very little thereafter
98% paved / 2% grass or dirt / 10% very poor landings :(

[SvingenB]

Helps to relieve the stress concentration in the corner of the web where the cracking is occuring.

Maybe, but in this case I can't understand how that would matter at all. The main problem is clearly an original design choice where the flange (on a structural beam) changes from being on the fwd side to the aft side with no overlap. Thus leaving a small section of the structural beam void of flange material which causes the shear web to carry too much compression/tension load. In fact, so much that it ends up cracking.

Since the main problem has not been addressed by the SB, the forces carried by the shear web is exactly the same amount as it was before. However, the added web material will of course make the stresses in the web much less than they were.

Fatigue in metals is a function of the main stress value and the stress amplitudes together with the number of cycles. Stress "peeks" as function of design means nothing as long as the critical values are controlled. In the SB, the single only thing that decreases stress is the added material on the web. Trimming of the flanges certainly help smoothing out the stresses, but has little or no effect on the max stress amplitudes. You cannot fool the basic laws how structural beams work.

[gear1]

RV8
IO360
Hartzell CS prop
1650 hours
Lots of acrobatics up to 5 G
Some unpaved runways
No relief notches
Tiny (1/8") cracks on top right and bottom left (blended out by creating notches).

Installing modification per SB

Questions for Walt:
1. one rivet hole measures .147" on the bottom angle (HS 714) and I slightly damaged (oval) one hole in the upper angle (HS 714). Should these holes be drilled out to 5/32" and AN470AD5-7 rivets installed?

2. The two rivets just inside the bend line (labeled "staggered rivet is oriented up" and its counterpart) seem very close to the notch adding to the stress riser. Would it be appropriate to move this rivet down 3/8"?

[Walt]

Installing modification per SB

Questions for Walt:
1. one rivet hole measures .147" on the bottom angle (HS 714) and I slightly damaged (oval) one hole in the upper angle (HS 714). Should these holes be drilled out to 5/32" and AN470AD5-7 rivets installed?

2. The two rivets just inside the bend line (labeled "staggered rivets is oriented up" and its counterpart) seem very close to the notch adding to the stress riser. Would it be appropriate to move this rivet down 3/8"?

I appreciate your confidence in me, but, I know my limitations... when it comes to deviating from an approved spar repair I think the engineer would be the best place to go for that info.

It's "probably" ok as most engineers will build in some buffer for mistakes, but I don't think probably is good enough in this case, get the answer from "the man".

[rvbuilder2002]

Since the main problem has not been addressed by the SB, the forces carried by the shear web is exactly the same amount as it was before. However, the added web material will of course make the stresses in the web much less than they were.
???
Not sure how forces/stresses can be the same and be less at the same time...

Fatigue in metals is a function of the main stress value and the stress amplitudes together with the number of cycles. Stress "peeks" as function of design means nothing as long as the critical values are controlled. In the SB, the single only thing that decreases stress is the added material on the web. Trimming of the flanges certainly help smoothing out the stresses, but has little or no effect on the max stress amplitudes. You cannot fool the basic laws how structural beams work.

As mentioned previously in the thread, this mod is not for making the structure stronger. Previous static testing has already proven that it meets the design requirements for limit and ultimate loads.
The SB is to a localized stress area that after lots of load cycles can possibly develop a crack. Tapering the flange of the fwd. spar, and confirming that there is a tapper in the top flange of the top angle does help further distribute the load through this area. This was substantiated with FEA and is also a fundamental engineering practice.

Please refrain from comments that might make people take shortcuts while doing the SB modification, without having personally done a full analysis of the structure.

[SvingenB]

Not sure how forces/stresses can be the same and be less at the same time...

Stress = Force/Area

The forces are the same. Your airplane weighs the same, you pull the same amount of G etc. Adding more material obviously decreases the stress in the material. ABC in engineering.

Tapering the flanges weakens the structure further. It does however, smooth out the stress distribution. But to what gain? Absolutely none stress wise. The stress at the weakest point does not change if you weaken the area around it. The strains could benefit from the tapering however, making the HS flex in somewhat the same way as before. This could in fact be important regarding vibration and also for the other SB, the cracks in the elevator.

Static loads and fatigue loads are different things. But stress and strain does not differentiate between the name of the load. To decrease stress, you increase material dimensions for a given load (force). This is the same for static loads and dynamic loads.

[rvbuilder2002]

I strongly recommend that people installing the doubler parts prescribed in the SB do not take short cuts and skip any of the steps.

[BillL]

Stress = Force/Area

The forces are the same. Your airplane weighs the same, you pull the same amount of G etc. Adding more material obviously decreases the stress in the material. ABC in engineering.

Tapering the flanges weakens the structure further. It does however, smooth out the stress distribution. But to what gain? Absolutely none stress wise. The stress at the weakest point does not change if you weaken the area around it. The strains could benefit from the tapering however, making the HS flex in somewhat the same way as before. This could in fact be important regarding vibration and also for the other SB, the cracks in the elevator.

Static loads and fatigue loads are different things. But stress and strain does not differentiate between the name of the load. To decrease stress, you increase material dimensions for a given load (force). This is the same for static loads and dynamic loads.

The stress is more than just the force/area as you know from solid mechanics. A notch will lower the area, but the strain is not evenly distributed, and that means resulting stresses are not evenly distributed. The well known concept of stress concentration is at play. Further, this is not a simple structure of load distribution due to stiffness differences between the components and added stiffness by the skin that build up to carry the loads imposed on the spar and load sharing.

Personally, I will completely trust the stress analysis and follow Vans instructions in the SB. IMO, any discussion of how this works, in detail, is well beyond the scope of this forum to definitively address.

Just my $.02

[David Paule]

....Static loads and fatigue loads are different things....

And they behave quite differently for ductile materials like the ones used here. For strength, the whole piece will be effective. Most localized stresses or strains will locally yield and distribute their excess load to the adjacent material. But for fatigue and crack propagation, the cyclic stress is generally below the yield level and the material around local load concentrations has not had the benefit of that distribution. It is affected by whatever load concentrations are caused by the geometry.

From what Scott has said, Van's has used finite element analysis to assess this. That analysis tool, when used for a linear static analysis with a properly modeled structure, is excellent for finding these load concentrations. It appears that is what led to this SB. Since he's said that this analysis also verified that the SB fix is indeed a fix, the SB would be perfectly adequate to correct the cracking issue here.

Since the cracking is a fatigue issue and not a static strength issue if there are no cracks, it's unlikely that the fatigue damage, which accumulates, can made to go away without it since the geometry of the structure has not been changed.

Bottom line - do the SB.

Dave

[turbo]

http://i1130.photobucket.com/albums/m537/turboeddie/P1010559.jpg

[GregM]

Something everybody should keep in mind...If you do not use the materials and don't follow the procedures as outlined in the service bulletin and deviate, then you have not complied with the SB. Just something that the FAA,insurance companies,and lawyers will take note of if they should be involved at some point in the future.

[Ken Martin]

I have a question about step 13 of this SB on page 8 of 20. (Ref Fig. 5). I couldn't find this addressed anywhere else prior to posting this so if I somehow missed it; my apologies.

Step 13 calls out a final drill of the fwd most hole in the top and bottom flange of the main ribs. No problem, I bought some #27 bits. However, on page 19 of 20 in Figure 11, the rivet callout for this location is still AN426AD3-3. If this is the case, why increase the size of the hole from the original callout? What am I missing?

[David-aviator]

I have a question about step 13 of this SB on page 8 of 20. (Ref Fig. 5). I couldn't find this addressed anywhere else prior to posting this so if I somehow missed it; my apologies.

Step 13 calls out a final drill of the fwd most hole in the top and bottom flange of the main ribs. No problem, I bought some #27 bits. However, on page 19 of 20 in Figure 11, the rivet callout for this location is still AN426AD3-3. If this is the case, why increase the size of the hole from the original callout? What am I missing?

I am not quite to that point but I think the rivet is a hole filler, they do not want the flange attached to the skin so the #27 hole is so the hole in the skin can be filled with the -3 rivet. It's bucked end sits in the #27 hole.

[Bavafa]

I have a question about step 13 of this SB on page 8 of 20. (Ref Fig. 5). I couldn't find this addressed anywhere else prior to posting this so if I somehow missed it; my apologies.

Step 13 calls out a final drill of the fwd most hole in the top and bottom flange of the main ribs. No problem, I bought some #27 bits. However, on page 19 of 20 in Figure 11, the rivet callout for this location is still AN426AD3-3. If this is the case, why increase the size of the hole from the original callout? What am I missing?

I believe it is to increase the size so the rivet can expand more to fill the larger hole since there is no mating piece to this hole. I could be wrong though.

[az_gila]

I have to wonder how the FEA copes with the poor sizing of the flanges with the older RV-6 kits, and shown in Turbo's pic -

http://i1130.photobucket.com/albums/m537/turboeddie/P1010559.jpg

Also most of the early models have poor "height control" of the parts fitting here (main rib, spar bent flange, the riveted on forward angles) and the skin is rarely smooth as it crosses over the HS spar.

Required edge distances are also missed in this area. Check the earlier pictures in this thread.

[Ken Martin]

I am not quite to that point but I think the rivet is a hole filler, they do not want the flange attached to the skin so the #27 hole is so the hole in the skin can be filled with the -3 rivet. It's bucked end sits in the #27 hole.

Thanks for the reply David. You make a good point. I will drill on...

[plehrke]

Did the inspection last weekend but had not removed the paint to be absolutely sure no cracks. Today Used Dan Horton's post (#548 in this thread) to use MEK on a cotton ball taped down with aluminum tape to soften polyurethane. Worked Great. Now sure no cracks.

RV6A
620 hours
180hp IO-360
Fixed metal prop
Quick built Kit 60171 circa 1999 (therefore built in the Philippians)
Never grass
Minimal acro
Small notches
No cracks

[estoro]

It took forever to try and figure out what the drawing "Figure 7 (RV-8)" was trying to tell me.
The note about the 'rectangle' "Match-Drill #30 Then Cleco, 8 Places", is not a part. It is showing the eight holes that are to be drilled. Poor drafting.
This line should be something other than a solid line.
Next: Steps 17 & 19 are too many words for what needs to be done. I am sure that a picture would be worth a thousand words, but these steps not clear. Confusing. Mainly Step 17-4 (paragraph, that is) and then Step 19 - 2.

I have figured it out, but took too long.

Ed

[akarmy]

Step 13 calls out a final drill of the fwd most hole in the top and bottom flange of the main ribs. No problem, I bought some #27 bits. However, on page 19 of 20 in Figure 11, the rivet callout for this location is still AN426AD3-3. If this is the case, why increase the size of the hole from the original callout? What am I missing?

When you squeeze the -3 in the #27 hole you get a perfectly double flush rivet that expands just enough to fill the hole and hole the rivet in the exterior skin. That rivet is no longer holding anything just plugging the hole after the spar flange is trimmed away.

[valsoar1]

1992 RV6
~ 750hrs
- No Notches
- No Cracks
- 160hp/Wood Prop
- Some grass/some acro

[laz]

I was just about ready to mount my HS on my 8 QB. I decided to just go ahead and do the SB. Since I did not have to remove the HS it was just the repair. Total time was 22 man hours. Not quite as bad as I thought it would be. It takes a while to understand the directions. The hardest part was drilling out the -4 rivets inside the spar.

If I knew how to post pictures I would do so.

[Arlen]

If I knew how to post pictures I would do so.

See: http://www.vansairforce.net/articles/ImagesInForums/images.htm

[kjlpdx]

after talking with an engineer at van's who was repairing the cracks on his -7 at the time, he said the finite element analysis program clearly showed a fatigue problem on the forward spar and that the fix he engineered was strong enough to handle the spars loads all by itself. apparently [my understanding of what he said] when loads are placed on the spar the top edge wants to act like a hinge, since the bottom is bolted to the fuse, and moves forwards and back, bringing on fatigue. he said about 15% of the high-time planes were having cracks.

[PCHunt]

after talking with an engineer at van's who was repairing the cracks on his -7 at the time, he said the finite element analysis program clearly showed a fatigue problem on the forward spar and that the fix he engineered was strong enough to handle the spars loads all by itself. apparently [my understanding of what he said] when loads are placed on the spar the top edge wants to act like a hinge, since the bottom is bolted to the fuse, and moves forwards and back, bringing on fatigue. he said about 15% of the high-time planes were having cracks.

What is the explanation for the cracks on the low-time aircraft?

[kjlpdx]

I didn't ask. our meeting was the first I had heard of it. I was giving him a hard time about how much he[an engineer] works on his plane compared to me[a carpenter]. so, this carpenter needs to do some inspections soon, because I have 1600+ hrs and used to fly aggressively.[like 5G stalls messing with an AOA meter for instance].

[Bill Boyd]

Empennage slow-built in '94.
No notches, no cracks found.
O-320 160hp FP Sensenich
almost all ops on turf, mild acro. 890 TT

Like most 16 year old RV's, she's showing age elsewhere - but not in the elevator spar :-) We did discover three loose jam nuts, two on the elevator and one on the rudder. No cracks there, either.

-Bill Boyd

[jcbarker]

Tail kit 2003
First flight 2010
~200 hrs.
Some aerobatics
No notches
No cracks

[kjlpdx]

tail kit 1993 (?) first flight 1997
1600+ hrs O-320 160hp sensenich FP
lots of aerobatics, spins early on
no hard landings ever
5G stalls [messing with the AOA, wish now I hadn't]
no notches [I didn't build the empennage]
H spar crack [tiny]

[Jesse]

Does anybody have a tally or chart yet? I wonder what percentage of >1,500 hr planes have cracks and what percentage of <1,000 hr planes do. It sure seems relatively high and quite low respectively.

[david roe]

I have a 700 hour RV8 and found the dreaded cracks. I'm thinking of going the Anti Splat.com fix. It seems less intrusive and uses stainless steel plates. Any ideas out there?

[Kevin Horton]

I have a 700 hour RV8 and found the dreaded cracks. I'm thinking of going the Anti Splat.com fix. It seems less intrusive and uses stainless steel plates. Any ideas out there?

I recommend you read all the comments on this thread (www.vansairforce.com/community/showthread.php?t=109945). In particular, pay close attention to posts 23 (http://www.vansairforce.com/community/showpost.php?p=855299&postcount=23), 25 (http://www.vansairforce.com/community/showpost.php?p=855345&postcount=25), 27 (http://www.vansairforce.com/community/showpost.php?p=855359&postcount=27), and 42 (http://www.vansairforce.com/community/showpost.php?p=856049&postcount=42).

[estoro]

David,

I recommend doing the Van's Fix.
1. It is not that difficult. The most difficult part is drilling out the heads in the interior portion of the stab. And it was only time consuming.
2. Riveting the structure together was easy.
3. When it comes time to sell, you will thank yourself.
4. You built this whole machine. You can most certainly do this fix. This really is a mind over matter procedure.
5. Just do it Dave. (and everyone else)

Ed

[chrispratt]

N898DK
Hours: 571
SB14-01-31 No cracks found (no relief notches specified in plans)
SB14-02-05 No cracks found
Engine: O-360-A1A

Chris

[david roe]

Thanks Kevin and Ed

I really appreciate you guys chiming in to help me clarify the issue for me. The work involved was never an issue. Just my ignorance. Kevin, thanks for posting the related links that I needed to read. The factory repair it is.

[estoro]

David,

Way to go. There was one thread that had a dozen pictures of the procedure. It was called "SB 01-31-14 Completed", but I have not been able to find where it disappeared to. I know it gave me confidence after viewing.

So can anyone help find this site?

Ed

[SvingenB]

I recommend you read all the comments on this thread (www.vansairforce.com/community/showthread.php?t=109945). In particular, pay close attention to posts 23 (http://www.vansairforce.com/community/showpost.php?p=855299&postcount=23), 25 (http://www.vansairforce.com/community/showpost.php?p=855345&postcount=25), 27 (http://www.vansairforce.com/community/showpost.php?p=855359&postcount=27), and 42 (http://www.vansairforce.com/community/showpost.php?p=856049&postcount=42).

Well, engineering vise and responsibility vise this whole thing is beyond belief when applying normal industrial norms and conduct used everywhere in every industry on this planet.

The owner/builder has sole responsibility for the structural integrity of the aircraft, no one else. Vans is in this case only a subcontractor, a consultant and a supplier of parts.

In any other industry, Vans SB would be considered only an idea, a vague suggestion. It will remain so until Vans idea was substantiated by Vans showing actual calculations. Actual calculations put forward in a report showing the weakness of the original design and the improvement of the new design. This is the normal way because Vans has no responsibility whatsoever in this matter. It is the manufacturer, the owner/builder, who is to decide if these calculations are good enough, are they done correctly, are they done with appropriate software, and most importantly, are they done by someone with adequate training, experience and understanding. This is not for Vans to decide or mean or suggest anything about, they are only doing a job here.

I'm not saying Vans mod is bad or anything, it probably is as good as it gets - probably. The point is that the whole process is NOT an engineering process based on facts and data. It is a system based on believe and hope and something I would call misplaced awe of Vans and blind faith. Again, the builder/owner is sole responsible here, Vans have no responsibility.

Now, there are some aeronautical engineering types here as well as very seasoned and experienced mechanical types. They have looked at the two suggested mods, and their impression is that Vans mod is by far the better one. That carries some weight, because you don't need to do a full FEA to see the basics of the two mods. The structure is not that complex. But, the complete lack of visible and obtainable facts and data and number crunching engineering is still here, so it is still a system of believes, far away from the engineering world I am used to.

OK, I got that of my chest :) I see this in many other parts of the experimental scene. An open system of sound engineering and practical experimentation being replaced with an obscured system of believe and blind faith towards some kit manufacturer who has no responsibility whatsoever for anything but the profitability of his company. This is wrong on so many levels.

[rvator51]

In my case, I don't think its "misplaced awe and blind belief"; I think its "trust". Since I am not an aeronautical engineer or want to spend a lot of money paying one to review this fix, I have to trust Vans. For me, I am comfortable trusting Vans based on their record.

[Kevin Horton]

Well, engineering vise and responsibility vise this whole thing is beyond belief when applying normal industrial norms and conduct used everywhere in every industry on this planet.

The owner/builder has sole responsibility for the structural integrity of the aircraft, no one else. Vans is in this case only a subcontractor, a consultant and a supplier of parts.


Did you require Van to supply a full engineering package before you started to build your RV-4? Or did you trust that he had properly engineered the design?

[david roe]

Ed

I think that this might be the post you're looking for. The thread is SB 01-31-14 Completed, post #8.

I'll try a link here but I'm not well versed with the tools here. http://www.vansairforce.com/community/showthread.php?t=109786

[Snowflake]

This is the normal way because Vans has no responsibility whatsoever in this matter.
...
An open system of sound engineering and practical experimentation being replaced with an obscured system of believe and blind faith towards some kit manufacturer who has no responsibility whatsoever for anything but the profitability of his company. This is wrong on so many levels.

It may be blind faith and optimism to say this, but I don't even remotely believe this is the case. Whether Van's has any legal responsibility is irrelevant. As Engineers Van and his staff have an ethical responsibility to report a problem in good faith when they find one. They have a further responsibility to put forth a solution for said problem only after analysing it to the best of their abilities. That they have published a solution suggests to me, as a fellow Engineer, that they have done their due diligence. As an Engineer, i'd love to see the calculations and numbers, for personal interest. But I don't need to see them to be confident that they exist.

In short: I trusted them to design the airplane I trust my life to, I think it's a small stretch to trust them to design a fix for it.

As for concerns over profitability, the impression I get from talking to Van and his staff is that this isn't their driving motivator in life. It's just a happy side effect of having designed the most successful kit plane in the world. If profit was their concern, the repair kits would cost more than $15.

[APACHE 56]

David,

Way to go. There was one thread that had a dozen pictures of the procedure. It was called "SB 01-31-14 Completed", but I have not been able to find where it disappeared to. I know it gave me confidence after viewing.

So can anyone help find this site?

Ed

Here they are:

http://www.vansairforce.com/community/showthread.php?t=110107

http://www.vansairforce.com/community/showthread.php?t=109786&highlight=completed

[SvingenB]

It may be blind faith and optimism to say this, but I don't even remotely believe this is the case. Whether Van's has any legal responsibility is irrelevant. As Engineers Van and his staff have an ethical responsibility to report a problem in good faith when they find one. They have a further responsibility to put forth a solution for said problem only after analysing it to the best of their abilities. That they have published a solution suggests to me, as a fellow Engineer, that they have done their due diligence. As an Engineer, i'd love to see the calculations and numbers, for personal interest. But I don't need to see them to be confident that they exist.

In short: I trusted them to design the airplane I trust my life to, I think it's a small stretch to trust them to design a fix for it.

As for concerns over profitability, the impression I get from talking to Van and his staff is that this isn't their driving motivator in life. It's just a happy side effect of having designed the most successful kit plane in the world. If profit was their concern, the repair kits would cost more than $15.

There is nothing wrong with Vans. Vans has stood the test of time, and so have all of Van's aircraft. Obviously Van is a top notch designer of airplanes, and a very talented business man. I have no reason to believe that every single one of Vans aircraft is anything but top aircraft designs. I'm just very surprised at many peoples reactions to the SB and the process around it. It shows a way of doing things, a way of operating, that is far away from any standard way in "the real" engineering world. I don't think it is healthy.

The producer of the aircraft do not have enough facts, experience or knowledge to decide if a mod is the correct mod, and the producer of the mod have no legal responsibility whatsoever in the aircraft, not even an obligation to factually verify that the mod is a sound one, not to the owner/producer of the aircraft or anyone else.

It is a system of belief and hope and faith. It is not a system of facts and openness and trust. It is not the engineering way of operating. As it is today, the producer of the aircraft is reduced to a blind consumer, yet he has all responsibility. The manufacturer of the kit is void of any legal responsibility and obligations of any kind, still he has all the authority.

I just find it very strange, that's all.

[magiccarpet]

In step #12 the plan shows a 2/32" offset from the rib's center line for the 4 holes which are to be drilled to attach the flange angle.
The upper most hole is 38/32" away from the center line while the lowest most hole is 36/32".
I don't question that, but can't see an obvious reason for it since the rib is symmteric.

More over, to me it looks that those measurements shown in figure 5 are taken from the web side of the rib. From L and R rib web's side? Correct?

[kjlpdx]

...As for concerns over profitability, the impression I get from talking to Van and his staff is that this isn't their driving motivator in life....

having just had a van's engineer volunteer to come to my cold hangar in the rain and freezing ice on a sunday and inspect my spars for cracks should quickly clear up any questions of ethics and motivations. talking with him about the FEA modeling for the fix convinced me that they are on track besides.

[lowandslo]

N25TS 1992 RV6
O360/hartzell CS, 10.5 pistons
2258 hours
Lots of high speed cross country racing
Lots of recent acro to 4G
No cracks.

[mspenc45]

I see in SB that Pre Punched is NA. I checked mine anyway RV 8 finished in 2011 680 hrs. mild acro IO 390, no cracks.
Hmm, where does it say pre puched is NA?

[60av8tor]

Hmm, where does it say pre puched is NA?

The table at the bottom of page 3. I agree it is misleading, but has already been addressed. I forget what the verbiage is actually intended to mean (do a search). But what it doesn't mean is that the SB is N/A for match-hole emp.

[lllewis45]

RV-7A
2005 quick build
306.8 hrs
light acro
No Cracks

[Mikey]

With well over 3000 hours and always a flyer---never a hangar king, Randy Richmond found cracks in all four locations during my annual this week. Louise and Paul say that I'll be having some surgery after I get out to Nevada next month. :(

[Gonzo24]

Just got my SB kit and I ordered a set of HS-405 root ribs to replace my old ones (long story). The ribs that came are part # HS00005 and look different than the old. The rib flange has 3 serrations and these is no joggle on the flange front.

Has Vans changed the root rib design for the SB now for newer emp kits being sent now? The SB instructions don't show the newer rib style if this is the case on pg 8.

Anyone else receive this new style and do you have pics of it in assembly yet?

Thanks,

[N804RV]

The table at the bottom of page 3. I agree it is misleading, but has already been addressed. I forget what the verbiage is actually intended to mean (do a search). But what it doesn't mean is that the SB is N/A for match-hole emp.

Hmmm.....

Does anyone have a copy of DWG-3pp, Rev. 3? Perhaps they could scan and post the figure 2 detail from the dwg, that the SB talks about so we could see it.

[mspenc45]

Did my inspection today and found no cracks in my RV8. Started in 2002, finished in 2009, 350 hours, no cracks and no reliefs :)

[Traash]

http://i58.tinypic.com/verdi9.jpg

I have 3 cracks in my RV-8. (Lower R, Upper R & L)
Kit 875 delivered and built in 1998.
1210 hours on airframe.
0-360 with Hartzell CS.
Extensive Acro, formation, off paved surface ops.
Notches were present.

Findings are:

Initial inspection found nothing. Second set of eyes noted a small crack on my lower right corner (picture somehow got flipped upside down). Stripped paint (Imron is tough), used die-penetrant and verified a crack emanating from notch much like the SB shows. Also noticed that I had'nt done a great job smoothing the notch. You can see the beginnings of a crack next to the micro-nick on the left side of the notch. It's obvious that this was in the group of first parts that I made. Not the workmanship level I try to achieve now that I know more.

Ordered repair kit and waited two weeks. Finished the rest of my conditional inspection. This was not a fun finding but couldn't have come at a better time.

Received kit and disassembled empenage. Found 3 of the 4 #3 bolts that attach rear horiz spar to vertical posts were not torqued properly. :eek: Installed over 10 years ago, torqued to spec and torque seal applied. Every annual I checked to see the torque seal was not indicating movement of nut and bolt. Torque seal was intact. Apparently over 10 years of use since painting and installing parts, the rather thick coats of paint on all parts had shrunk and reduced the torque without any external evidence. I hadn't used the proper method of securing torqued parts. :mad: All mating surfaces should be free of paint to avoid this issue. Be advised.

After removal of the ribs I found two more cracks on the upper right and left that had been covered by the rib flange. A little scary to think that I had those cracks and were it not for the SB I would have never seen them. For that matter I don't believe that I would have seen the original crack during my conditional inspections due to its small size and being covered with paint. That's why the SB has you remove paint before inspecting.

Drilling out the reinforcing bars proved to be a two-man operation. I had no problem popping off the heads and driving out the rivet shank with a punch. After filing the required notches (I already had notches from original build. Don't remember putting them in but they were there. Non pre-punched kit) I was able to remove two of the cracks and the third had propagated to the rib flange attach hole.

I installed all the parts but used a slightly different method to align the parts. I was able to cleco the bars to the VERTICAL stab forward spar attach points and then align the reinforcing plates. This made it easy to ensure alignment of the bend angles and proper clearance for all the parts to fit rather than the measure method that the SB described. I was able to make sharpie pen marks on the doubler plates through the existing holes in the bars.

http://i57.tinypic.com/2q3akoo.jpg

I then clecoed the doublers to the HORIZONTAL spar web, re-aligned the doubler plates using the sharpie marks and side-grip clecoed them in place. Triple re-check everything aligned and commenced to drilling from center to outboard tip, clecoing every hole to keep it tight. Before removing to debur I slipped the main rib into place with the new attach angle side-grip clecoed in place through the lightning hole. Match drilled the 8 attach holes (4 in rib, 4 in spar web) into the attach angle all while clamped in place rather than the SB method of removing to drill. All parts drilled in place before removing or riveting anything.

To date I have hand squeezed the rivets in the center section. Awaiting my next day off to tackle the ones inside the HS. Looks like my offset rivet set and a nice tungsten bar will work fairly easily.

Sure am glad I did this. :) As always, I found more than I was looking for.

[UnPossible]

RV-7A - finished in 2012... approx. 120 hours
Relief Notches and no cracks so far.

Jason


http://i60.tinypic.com/bg7pmb.jpg

[SteveHRV7]

RV7a, IO-375 with a CS prop
No acro (yet)
56 hours total time
No cracks

[jordanRV6]

Check out the SB kit at www.antisplat.aero.com.. It is alot less work and you don't have to remove your ribs. They have a video that you can watch on the site.. Check it out.

[kjlpdx]

I will trust van's engineer, rian, on this issue.

[Mick.B]

Just got my SB kit and I ordered a set of HS-405 root ribs to replace my old ones (long story). The ribs that came are part # HS00005 and look different than the old. The rib flange has 3 serrations and these is no joggle on the flange front.

Has Vans changed the root rib design for the SB now for newer emp kits being sent now? The SB instructions don't show the newer rib style if this is the case on pg 8.

Anyone else receive this new style and do you have pics of it in assembly yet?

Thanks,

Yep, they have changed the HS 405 to HS00005. It is different. Trying to work out what way it goes around ? Not any docs or pics of it. Any takers ?

[rvbuilder2002]

Yep, they have changed the HS 405 to HS00005. It is different. Trying to work out what way it goes around ? Not any docs or pics of it. Any takers ?

The HS-00005 (if I am remembering part #'s correctly) is not relevant to doing a field installation of the S.B. on a finished horizontal stabilizer.
It is a slightly shorter rib to account for the added thickness of the HS-00001 or HS-00003 Doubler so that trimming the fwd rib flange and replacing it with a piece of bent angle is not necessary.
It is intended for new builds only because of the difficulty of properly positioning and match drilling to skins that are already dimpled.

[jimbower]

So, has anybody used the antisplat mod for the HS? Can we hear from some engineers about this?

I would like to hear back privately.

Jim Bower
RV-6A flying since 2011

[mcydrake]

Hello VansAirforce community. This is my first post! My wife and I have just started building our RV7 empennage that arrived just a week after the service bulletin was issued. Luckily I got all the new parts but unfortunately I'm a guinea pig for the new Horizontal Stab build. Here are some pictures of the work in progress and of the new drawings. Unfortunately, I've found quite a few errors in the drawing/instructions based around these new parts and have called Vans for clarification. I THINK what I've done up to this point is right.

Here are some links to my drawings and a couple shots of the new parts:
http://n928dd.files.wordpress.com/2014/03/sam_2899.jpg
http://n928dd.files.wordpress.com/2014/03/sam_2898.jpg
http://n928dd.files.wordpress.com/2014/03/sam_2899.jpg
http://n928dd.files.wordpress.com/2014/03/sam_2901.jpg
http://n928dd.files.wordpress.com/2014/03/sam_2902.jpg
http://n928dd.files.wordpress.com/2014/03/sam_2880.jpg

PM me if you'd like pictures of anything specific or if you're in the area and want to check out the build in progress.

Feel free to check out my build site to see other details on the new HS Front Spar (Link in Signature).

[Mike S]

Hello VansAirforce community. This is my first post!

Mike, welcome aboard the good ship VAF!!

Another Mike, that is a good thing:D

[BSwayze]

Just got my SB kit and I ordered a set of HS-405 root ribs to replace my old ones (long story). The ribs that came are part # HS00005 and look different than the old. The rib flange has 3 serrations and these is no joggle on the flange front.

Has Vans changed the root rib design for the SB now for newer emp kits being sent now? The SB instructions don't show the newer rib style if this is the case on pg 8.

Anyone else receive this new style and do you have pics of it in assembly yet?

Thanks,

Yep, they have changed the HS 405 to HS00005. It is different. Trying to work out what way it goes around ? Not any docs or pics of it. Any takers ?

The HS-00005 (if I am remembering part #'s correctly) is not relevant to doing a field installation of the S.B. on a finished horizontal stabilizer.
It is a slightly shorter rib to account for the added thickness of the HS-00001 or HS-00003 Doubler so that trimming the fwd rib flange and replacing it with a piece of bent angle is not necessary.
It is intended for new builds only because of the difficulty of properly positioning and match drilling to skins that are already dimpled.


I just finished doing the SB and I'm in a position to comment on this. I have some pictures, too. My HS had the older HS-405 ribs. I got them all drilled out and proceeded to cut the end flanges off, per the directions. Like a big dummy, I cut off the wrong end on one of them. (This is easy to do, they look so similar. Pay attention and be careful!) Rather than rivet a new flange on both ends, I opted to just buy a new one from Vans. I didn't know they had changed to new HS-00005 until I went back to work and noticed the differences.

The older style didn't have the relief notches that the new one has. It required more work to bend the flanges to 90? and flute them to straighten out the rib so it wasn't warped or twisted. The new style is very nice in this regard. The flanges are perfectly bent at 90?, no fluting required.

These parts are among the few in the kit that aren't pre-punched, so Scott is right... there is potential difficulty in positioning and drilling to skins that are already dimpled. If you've ever noticed, dimpled holes become slightly larger than the drilled #40 hole, so careful drilling techniques are necessary to make sure the new holes you drill are centered under the dimpled holes in the skin.

I wish I had known that these new ribs are slightly shorter to account for the thickness of the doubler. The first thing I did when I got back in the shop was to cut off the forward flange and proceed with the directions. I could have saved myself all that trouble! Anyway, it's done and here are some pictures:

The start of the project... lots of rivets to drill out. Here are all 4 ribs after successfully removing them. (I know... I have mis-matched primer. New builder at the time :) )

http://www.europa.com/~swayze/RV-7A/SB/P1000956%20(Custom).JPG

Here's the new rib, being carefully drilled into place. It was nice not to have to do any fluting or bending of the flanges. Note that the doubler is already positioned and clamped in place as well.

http://www.europa.com/~swayze/RV-7A/SB/P1010027%20(Custom).JPG

Later on, the rib is now deburred, dimpled, and primed as normal. The doubler has been riveted in place. Now comes the clamping and drilling of the new end flange piece. As I said above, I wish I had known that I could have avoided this if I had known that the flange was made a bit shorter to accommodate the thickness of the doubler!

http://www.europa.com/~swayze/RV-7A/SB/P1010036%20(Custom).JPG

When I got all that work finished and the new flanges riveted to the ribs, here they are before final installation back in the HS. Interesting side-by-side comparison of the new with the old.

http://www.europa.com/~swayze/RV-7A/SB/P1010038%20(Custom).JPG

http://www.europa.com/~swayze/RV-7A/SB/P1010039%20(Custom).JPG

And finally, here's the new rib, riveted in place.

http://www.europa.com/~swayze/RV-7A/SB/P1010051%20(Custom).JPG

Just for comparison, here's the old one back in place as well, on the right side.

http://www.europa.com/~swayze/RV-7A/SB/P1010053%20(Custom).JPG

In the end, it turned out great. I'm very happy to have this done.

[mcydrake]

Got the skins on only to find issues with the new set of instructions/plans. In the newest plans, Vans has you trim the HS-702 back:

http://n928dd.files.wordpress.com/2014/03/20140315_164728-e1394930211599.jpg

But the HS-00005 flange doesn't extend as far enough forward to get to the hole that used to attach to the HS-702. To make things more confusing, Van's new set of drawings doesn't show the hole that is causing me grief.

Old Plans:

http://n928dd.files.wordpress.com/2014/03/20140315_164836-e1394930440190.jpg

New Plans:

http://n928dd.files.wordpress.com/2014/03/20140315_164712-e1394930496975.jpg

The results are me scratching my head, wondering I did something wrong, and moving onto the Vertical Stab until I can get through to Vans on Monday.

http://n928dd.files.wordpress.com/2014/03/sam_2913-e1394930602599.jpg

Does anyone who has played with these new parts catch if I missed something?

[rvbuilder2002]

Got the skins on only to find issues with the new set of instructions/plans. In the newest plans, Vans has you trim the HS-702 back:

http://n928dd.files.wordpress.com/2014/03/20140315_164728-e1394930211599.jpg

But the HS-00005 flange doesn't extend as far enough forward to get to the hole that used to attach to the HS-702. To make things more confusing, Van's new set of drawings doesn't show the hole that is causing me grief.

Old Plans:

http://n928dd.files.wordpress.com/2014/03/20140315_164836-e1394930440190.jpg

New Plans:

http://n928dd.files.wordpress.com/2014/03/20140315_164712-e1394930496975.jpg

The results are me scratching my head, wondering I did something wrong, and moving onto the Vertical Stab until I can get through to Vans on Monday.

http://n928dd.files.wordpress.com/2014/03/sam_2913-e1394930602599.jpg

Does anyone who has played with these new parts catch if I missed something?

These holes are abandon when doing a SB retrofit to a finished horizontal stab. (holes get filled with a rivet set in the skin only).

The holes aren't shown in the new drawing because they have been deleted from future skin production. Because of parts still in inventory, it looks like you got a skin that has the unused holes. They are not a factor structurally, and will be hidden under the emp. fairing so not a factor visually. You can leave them as is (less desirable because there will be future questions whether something was forgotten), dimple and insert rivets, or slightly machine countersink and install NAS1097 3-3 rivets (the method I would use).

[McGooey]

Brand new to forum. Just completed 14-01-31. Down for a month. Disassembled empennage, then delivered horizontal stab to to expert IA that repairs Cessna jets for a living. Took him 16 hours total to do the repair under ideal conditions. Came out beautiful.

Originally couldn't find the crack. Took the IA 2 minutes to find it with flashlight and mirror. After disassembly, the crack picture of my horizontal stab is identical to the picture on the Service Bulletin.

IA reports that the service bulletin was clear and understandable, and support from Van's was excellent. He was able to talk to engineers directly.

Happy to be back in the air.

Tom McGee

[turbo]

Welcome to =VAF= Family. :cool:

[Andreas68]

No cracks found in HS or Elevator spars. No relief notches.

Steve Giesecke
RV-7a
Aerosport 360 Fixed Pitch
400 hrs total time
No acro with this owner (builder did a few rolls)
No dirt strip landings

[PCHunt]

RV-6, 180 hp, C/S prop, 1138 hrs since 8/95. No relief notches, No Cracks.

RV-6A, 150 hp, FP prop, 415 hrs since 10/97, No relief notches, No Cracks. The corners on this plane are pretty rough, very sharp corner, even under magnification. Still, no cracks. Go figure?

[rwarre]

I thought it might be a good idea to do this mod with the anti splat aero doubler since it was time for the condition inspection. It took most of the day to get the eight rivets out on one side while keeping the existing rivet holes in good condition. The doubler for Anti splat does not fit in my RV7 as easy as it looks on their video. I am going to put the rivets back in and forget about the SB until I see a crack. Since I don't do aerobatics and everything appears solid, I can't see the point.

[fl-mike]

Can someone tell me the max width of the F-884 VS to HS spar attachment plate? I'm incorporating the SB on my newly built HS :mad: and want to make sure I have adequate distance between the SB doublers. Don't have the fuselage kit yet.

Thanks

[RV7AV8R]

600 + hours on my RV7, O360 with CS prop and no cracks. One side had a relief notch and the other did not, go figure. Almost zero acro, tried it and did not like it.

[AlphaSierra85]

I am building a tail kit for an RV7 from 2007. I purchased the Horizontal stabilizer SB kit from Vans. I also bought the new root ribs(HS0005). I am not sure if I need to drill an additional hole in the rib and skin. Has anyone run into this? In the updated drawing there are two holes in the front flange of the rib. I know the old skins have an extra hole that isn't used anymore. I'm wondering if I should add a hole aft of the unused hole.

New builder, so any suggestions are much appreciated!

[Joness0154]

I am building a tail kit for an RV7 from 2007. I purchased the Horizontal stabilizer SB kit from Vans. I also bought the new root ribs(HS0005). I am not sure if I need to drill an additional hole in the rib and skin. Has anyone run into this? In the updated drawing there are two holes in the front flange of the rib. I know the old skins have an extra hole that isn't used anymore. I'm wondering if I should add a hole aft of the unused hole.

New builder, so any suggestions are much appreciated!

If I understand what you're saying correctly, you want to add an additional hole/rivet location to replace the one that isn't used anymore?

No need to do that. You'll be fine with the existing holes/rivets in the skin.

[AlphaSierra85]

Thanks! I figured it wasn't a problem. I called Van's and they told me the same thing.

[pilot28906]

I plan on doing Van's SB fix and wanted to ask if there is anything different I should do as my HS has not been drilled to the fuse. yet.

Thanks,

[bddalm]

Mine wasn't attach either. The repair is still the same. If it doesn't have paint, you could considered drilling more of the skin fasteners for better access.

Brian
Georgia
Building an RV7

[pilot28906]

Thanks. I started drilling out rivets today.

[six_rabbits]

I've found a few errors in the instructions for SB 14-01-31, and I've spoken with Van's builder support to verify they are in fact, errors. Here are the corrections:

1) in Step 27: Figure 8 should be Figure 10. Trimming to a 5/16" edge distance is optional, but the edge distance should not be less than 5/16".
2) in Step 31: Figure 10 should be Figure 11.
3) in Step 33: Step 6 should be Step 10.

When I asked if Van's would re-issue the SB with these corrections, the rep. indicated that it was unlikely.

Also, it was difficult for me to understand Figure 3 until I turned it upside down. Then it made perfect sense. It's a view from under the HS, looking forward and to the right of the nose.

I hope this helps folks out there that are compelled to read and understand the directions before starting.

[LifeofReiley]

Really... ? You would sure think they would want to get the correct information going out to the customer and it would probably cut down some of the phone calls to Van's questioning the SB and the process. Go figure. :confused:

[Snowflake]

Welcome to VAF, @six_rabbits!

It's possible that the number of calls they get will help them track who has actually applied the SB and who still has it sitting on their desk waiting for a rainy day... (I say, as I mark up the copy on my desk...).

[pilot28906]

It took 22 hours. Not too bad, just follow the instructions and take your time. Glad it's done.

[rv6n6r]

RV-6
1200hrs
no relief notches
no cracks

[longline]

I complied with the SB on my (new to me) RV8, kit dated 2002. Has not flown yet, but seemed reasonable to do it now, before fitting to the fuselage for the last time.

Van's "repair" parts did not, repeat NOT, make sense or fit. Angles were correct, but the holes semi overlapped in several areas. Ended up making a one piece plate that runs the entire distance across the exposed section of spar, instead of two parts. I removed a lot more of the 3/32 skin rivets than "required", as it made access somewhat easier.

The spar had no relief notches, and had distressed metal where the bend lines terminated at the edges of the spare. It would probably have cracked over time. The surfaces were not painted, so it only took me about 12 hours to do this SB from start to beer.

No biggie deal.

[mrblob]

For anyone keeping score, I complied with the Service Bulletin on my -7. I didn't keep close count, but I think it took 20-25 hours all said and done.

After the Service Bulletin was released in January, I inspected and found no cracks. That was with about 360 hours of flight time with a 3.0l Subaru engine and about 10 hours into my new IO-370 and hartzell prop. All landings on pavement, mild acro, nothing crazy.

I inspected again during my annual at the end of October, and found a very small crack (~1mm) in the upper left corner. At this point, I have about 100 hours on the new engine. I'm not sure if the engine change is related to the crack (different vibrations, and whatnot), but it's a data point.

[219PB]

I am a DAR in the Northwest. I just got off the phone with Vans. the service instruction is a bit vague, and it will be rewritten soon. Meanwhile, the later kits have a heavier cap in the area of the crack, that is what is meant as "not applicable" on the "chart". That does not mean that the SI does not apply to those aircraft, just the drawing. All RV 6-7-8 aircraft need to be inspected prior to further flight for these cracks.

also, per 8130.2G(change 1) and 8100-1 for all new aircraft being inspected for a certificate of airworthiness, all Vans service Instructions must be current at the time of issuance.

Some have said that the SI does not apply to an Experimental Aircraft. Here is the rub........ how can the repairmen or A&P certify that the aircraft is in a condition for safe operation, when the manufacture of the kit says it is not? I would not want the liability when the lawyers start smelling blood.

While we are on the subject...... I have found aircraft with excessive clearance between the forward vertical attach bracket, with the bolting together causing stress on the bend radius. Vans plans call for a shim if the surfaces do not mate exactly. good time to take a look. I'm heading out to the hangar now to inspect my -7.

Fly Safe!

Gary Brown
ATP A&P IA CFI DAR

I am questioning the statement above. Gary, are you stating that the doublers would have to be installed prior to receiving a certificate of airworthiness or would just the inspection have to be done? Of course 0 hours and there will not be a crack. My aircraft is still under construction but the empennage is complete and I am concerned about messing up a rivet hole and having to remanufacture a HS. Then I would have to match drill the holes attaching to the empennage.

Basically, can I get an airworthiness certificate and continue my annual inspections per the SB?

[rvbuilder2002]

Basically, can I get an airworthiness certificate and continue my annual inspections per the SB?

Yes. You should be able to.
Not having the doublers installed does not make the aircraft "not in a condition for safe operation", as long as there are no cracks present (nearly impossible on a brand new airplane).
If any other model RV without the doublers "is" in a condition for safe operation if it is inspected and has no cracks, then your airplane is no different, and is in compliance with the SB.... as long as the periodic inspections are done until the doublers get installed.

BTW, there is not any RV-6, 7 or 8 that this SB is not applicable to. The SB applies to all kits of all vintages.
The chart Gary was referring to is in Step 6 where you are instructed to verify that the corners of a flange were relieved as shown in a magnified view in the next figure. What the chart means, is that for certain vintage kits, "this step doesn't apply because they had pre-manufactured reinf. angles that had the corners relieved when they were made, so you don't need to check.

[aviator68]

Hi,

when i order now a 7, the problems are fixed from Vans site?

The Parts for the repair are included and the plans chanced from vans?

Thank you for an answer.

Chris

[rvbuilder2002]

Hi,

when i order now a 7, the problems are fixed from Vans site?

The Parts for the repair are included and the plans chanced from vans?

Thank you for an answer.

Chris

Yes, the change was incorporated into the standard build of all the empenage kits effected.

[Iluke]

I'm about to begin disassembling my HS to install the SB required doublers & I have a question for those of you with more experience drilling out rivets.

Should I buy a rivet removal tool like the one sold by Brown or the Yard Store to use here? It looks handy for removing button rivets, but only if there is room to use it I suspect I'm not sure there is room inside the HS to make use of it.

Anyone try one and know for sure?

thanks

[wirejock]

Ivan
I can't comment on the tool but I can impart some drilling techniques I learned on the HS SB repair. Unfortunately I learned them late after botching the job. I just finished drilling the skins off. All 540 of them.
Some may disagree but here goes.
Use a punch. Make a good centered mark.
Use a pilot drill bit much smaller then the rivet shank. I'm using #47. Too small and it may break. Don't ask. Use high speed and very little pressure.
Bump the trigger and look at the drill mark. Now's the time to get centered. It's tricky but you can coax it to center. Practice on some scrap.
Hit again and look. Continue till you have a centered hole and drill to the depth of the head.
Switch to to correct drill but use a drill stop so it will only go in the depth of the head.
Use an old bit to pop the head off.
Now you can see the center of the hole.
Use the pilot again to drill the rivet in the center deep enough to clear the parts. This should weaken the grip enough to punch it out. You can also grab the shop head with a pair of side cutter pliers and it should pop out. The tough part is drilling with a right angle tool.
My error was drilling without a pilot hole and going crooked. I ended up with one egg shaped hole the engineers said was too big. Over #20 and the part has to be replaced.
Download the latest SB. They added a page about elongated holes.
I decided to disassemble, order two new forward spars, angle reinforcements, main and nose ribs and reassemble the HS. YMMV

[bddalm]

Ivan Luke - Take a look at the following how-to video: https://www.youtube.com/watch?v=HgE0T8EMaZk. In it, I show different techniques for removing rivets from the horizontal stabilizer. One of them uses the tool you mentioned. Message me if you have any questions.

[Randy]

Brian,

Thanks for posting that video! It makes the instructions and previous posts make sense where otherwise it can be a little difficult to grasp what is being discussed without memorizing all the part numbers etc.

I think videos like that should be part of the instructions on any repair of service bulletin that is this involved.

Randall in Sedona

[wirejock]

43 man hours. It didn't go exactly as planned but it's done. Engineers recommended replacement of one of the spars and angles due to an egg shaped hole. It seemed logical to do it all over so I completely disassembled the HS and replaced both the forward spars, the inboard ribs, the reinforcement angles and installed the doublers. Basically I built the HS twice. Glad to put this one behind me.
http://i60.tinypic.com/1z659qc.jpg

[Iluke]

Brian, Larry-
Thanks for the tips- very helpful.
I got everything disassembled successfully and was working on positioning the doublers when I found a dimension call-out in the current version of DWG 3 (on the CD) that really ought to be in the SB instructions. View B-B shows the inboard edge of the doubler set at 2 1/4 inch from spar center line. Using this made all the holes line up perfectly. Much more precise that trying to line up the bend-lines.
-Ivan

[tikicarver]

anyone know if on the updated plans they use these doubles exactly like the SB or do they go back to building like the -4 H-stab spar.

I was curious why this SB didn't apply to the -4. So I borrowed a set of -8 plans from a friend and i could see why.
In the -4 the doubler is basically already there,except it is installed on the front side of the spar and is "T" shaped so the top part of the "T" is used for attaching the V-stab. It is one piece that extends all the way across the center of the spar. Seems like it would be a much cleaner fix on new builds rather than having two pieces.

[wjb]

So, a long holiday weekend, but no helpers around to finish up the fuse riveting ... what to do? SB-14-01-31, a bit of a dreaded chore.

However, it only took 19 hrs, including fabricating replacement HS-00003's since I buggered the edge distance on one. So happy to have some spare F-704H 0.063 stock from a previous do-over in my "waiting to be an airplane part" bin. 60 mins, the bandsaw, the file, the scotchbrite disk, drill press, and a mini-bender, and we have a perfect set of replacements (No Van's web store for me, ha ha!)

Overall, a very successful project. I found that the flexible "snake" extension on my dremel with a #30 drill was perfect for drilling out the #4 rivets between the HS 710/714's and the spar. Drill enough to get the heads off, separate the 710/714's from the forward spar, and then use the drill press to drill a #40 hole down the middle of the #30 rivets. With the material removed, the shop heads came out with just a bit of elbow grease, and the process minimized the enlarging of the #30 holes.

It all went back together very smoothly. Please, to not fear...

[pilotgabe]

As you all know a SB does not have to be complied with, as it's just a recommendation. An AD does according To the FAA.

[rvbuilder2002]

True.
But the FAA doesn't issue AD's on experimentals (other than extreme circumstances), so it is left to kit manufacturers. They can't issue AD's, so if one is issued it should be at least seriously considered.
Van's doesn't issue a structural related SB unless it is considered important.

[vic syracuse]

Keep in mind that at the Condition Inspection SOMEONE has to sign a statement that the aircraft is in a condition for safe operation. My opinion, and mine only, is that it might be questionable doing that without complying with the SB's.

For that reason, I do insure they are all complied with. :)

Vic

[DaAV8R]

I'm trying to understand these most recent comments. Are you guys implying that the reinforcement needs to be installed regardless of whether cracks exist?

The bulletin allows for inspection prior to further flight and then each annual inspection. Maybe I'm reading too much into these comments or not reading the bulletin correctly.

[RV6_flyer]

I'm trying to understand these most recent comments. Are you guys implying that the reinforcement needs to be installed regardless of whether cracks exist?

The bulletin allows for inspection prior to further flight and then each annual inspection. Maybe I'm reading too much into these comments or not reading the bulletin correctly.

You are correct. Being an A&P and very knowledgeable on RVs, all SBs need to be complied with for me to sign off the once a year "Condition Inspection." SB 14-01-31 requires that the reinforcement be installed if a crack is found. If a crack is found, I will NOT sign off the aircraft until after the reinforcement spelled out in SB 14-01-31 has been installed.

I prefer that the reinforcement be put in before the crack develops. I would like to think that most owners that were not builders schedule down time to install the reinforcement before a crack develops instead of wait till they are forced to have the aircraft down because of a crack.

[BobTurner]

I'm trying to understand these most recent comments. Are you guys implying that the reinforcement needs to be installed regardless of whether cracks exist?

The bulletin allows for inspection prior to further flight and then each annual inspection. Maybe I'm reading too much into these comments or not reading the bulletin correctly.

You are reading it correctly. Inspecting the area (and finding nothing) IS complying with the SB. The comments were directed at the statement that "...you don't have to comply with SBs" which is true, as long as someone feels they can sign off the condition inspection without looking there(!)

[amaris]

On DWG 3r4 and the SB drawing, they show conflicting info.

SB shows the 3/8" side to be down and the plans show the 3/8" side to be up. I of course already separated the pieces. Based on the way the edges are drawn in the SB and the 3/8" side, those look more accurate.

But wanted to double check...

Thanks.

[garrys]

How do I get on the distribution list for Vans planes. I am the original purchaser of the kit.....the builder....and the one and only owner. I have never gotten any correspondence from Vans regarding service bulletins. I just happened to stumble on this one via this forum.

[SmilingJack]

How do I get on the distribution list for Vans planes. I am the original purchaser of the kit.....the builder....and the one and only owner. I have never gotten any correspondence from Vans regarding service bulletins. I just happened to stumble on this one via this forum.

Book Mark this:

http://www.vansaircraft.com/public/service-rv8.htm


And check in daily to the =VAF= site and the fine people here will surely list anything new....