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Question if you ARE building.

bret

bret

Well Known Member
In light of the resent SB, I am sitting here in my living room, with the HS behind me, trying to decide if I want to tear it apart for the upgrade. UGG!
Just wondering how many folks that are still building if they are going to install now, or take their chances and wait until THE crack appears on the forward spar? So many questions, what if it dose not cure the problem, what if everyone else dose and the SB install affects the resale value........
 
I'm building an RV-3B, so only one of the SBs applies to this airplane. And yes, I plan to add the kit before I assemble the tail to the as-yet unbuilt fuselage.

One of the reasons is that I'm actively building, so this is just another task. Once it's flying, it'll be a whole different matter.

Dave
 
MY opinion

Mine only, but if I had the horizontal OFF and in the same room with me, I would go ahead and do the SB. IF you are not in a hurry, then wait as there could be some other fixes forthcoming, as there always seem to be some creative ones out there. However, for $15 VAn's has already determined a fix and they did it based upon some very sound engineering. So, certainly do it before you place it on the aircraft and before paint.
I am currently building an 8, and I intend to do exactly what I am recommending you do. :)

Vic
 
I am going to do mine

I still have my tail in my garage and I plan to do both SB's once I finish sealing my tanks.

Edit: After posting this, I emailed Vans Tech Support to ask if I should perform these service bulletins on my HS and elevator. Here is Joe's response:

"Per the SB you fall into the 1st condition. You should leave them alone and inspect annually once you are flying."

So, I will not be performing these SB's on my not yet flying parts.
 
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Not at this time

The HS and elevators are finished AND painted - but not on the airplane yet (still painting the fuselage). I think I will do the inspections for a year or two. My forward spar has the relief notches in them - I remember putting them there very well.
 
blueflyer said:
I still have my tail in my garage and I plan to do both SB's once I finish sealing my tanks.
Click to expand...

Shoot, I forgot about the other one. I was thinking about the suggestion Walt made about the washer under the nut for the elevators. No flight (yet) no harm or crack. It think it would spread the load out significantly as he described.
 
Yep, gonna' do it. It really will only take a "few hours" in our case.
 
if in hand, and not painted... no questions, just do it

If you have a vertical stabilizer that is not on a flying aircraft it would be silly to press forward without addressing this.
 
blueflyer said:
I still have my tail in my garage and I plan to do both SB's once I finish sealing my tanks.
Click to expand...

Same here but I plan to wait till in between wings and fuse and see if there are any changes to the SB kits. I plan to do both the HS and the elevator doublers.
 
I do not see paint being a problem, I am painted. What I worry about is the success of drilling out those -4 rivets under the skin without making the hole bigger. You mess up drilling out those angles and you are starting over. I have drilled out my share of rivets but not with an angle drill. Maybe a surgeon with a De Vinci machine (um, Craig) could do it.
 
building

Horizon finished, not painted not installed, ordered sb parts. Will install when they arrive.
 
A couple of days away from riveting the elevator together. Now adding the doublers as part of the process.

Wait and see on the HS. However I can't see myself tearing it apart when I can build a newer, better one in less than a week.
 
I'll install both SBs

My emp is built and installed, but not painted. It sucks, but I'll go ahead and take it all down and apply both SBs now, then reassemble and press on. If I end up turning a couple of #40 holes into #30 holes, well...that's what Avery's Oops Rivets are for. I'd rather add a day to the build to be done with this issue.
 
Ok, just ordered parts, sheesh, I envy you that are just starting out. If any good comes out of this, is, four years later, maybe redoing a rivet or two that was not perfect being a new builder of my HS in 2010!
 
SB's

The cost is $51+ shipping for both -4 kits.There in production now.I put my name on the list. I emailed support for more info and got this email back today.

"We would recommend you do specifically and only what is in the SB. The weight added to the tail will make no detectable difference to the W&B"

If your painted and flying and have inspected,then you have complied with the SB sans the recurring inspections. If you haven't painted and are not flying its a tough call. I'll buy and hold the kit till I come to that bridge (install time) just to see how time change's the scope of the project.But common sense,resale value,safety,will nag at me till I do it and log it in.
RHill
 
Not me

Generally speaking I think many are making a bigger deal out of this than it really is. I am going to follow the service bulletin exactly. The bulletin says to inspect once a year and if no cracks are found, do nothing. That is exactly what I'm going to do.

There seems to be a consensus that the stab is somehow better after the fix is installed. The bulletin doesn't say that. Additionally, it looks like the repair may make it difficult to detect a future crack. I will inspect and if I find a crack, I might just replace the stab and continue the inspection on the new spar/stab.

Think about it this way. If you have a flying airplane and you find a crack at the inspection, it is unlikely that the crack occurred on the last landing prior to the inspection. That means that Van's is OK with flying the plane with a crack until the next inspection.

My Cessna 120 has very very similar requirements as outlined in an old AD. Most Bonanza's require a die penetrant inspection every 500 hours on the main spar carry thru structure. This type of problem is not isolated to the RV's.

If Vans changes the bulletin stating this repair needs performed before further flight, I will perform the repair immediately.

I do think it would be prudent to remove any primer and paint on the areas which require inspection. I may tape off the hinge points to prevent finish paint from covering these areas. This will allow a thorough inspection at later dates.
 
I will install the HS SB

The SB indicates the HS changes can be done proactively - so I will.

As for the elevators no such comment; Stirling at Vans did not talk me out of it in our email exchange but did suggest the occurrences are limited, attributing it to hinge alignment...talking it down if you will. That lends credence to the comments made in posts 15 and 16. So I will ponder it a bit, but I am at that point on the elevator and with it open it would be easy to do.....perhaps easier for me than it would be for a future second owner if there is one.

Appreciate the feedback on this thread as we are in a different place than those already flying.
 
Question if you ARE building

"If it ain't broke don't fix it." I put too much blood sweat and tears into my HS to go trying to mangle it up drilling out 120 rivets. I have complied with SB. There are no cracks. I will put the washers under the jam nuts, but I can do that without tearing anything up. With 5 or 6 thousand airplanes flying I feel pretty good about my decision.
 
Some 'theory'

Since I'm not yet building, er constructing my RV-12 kit, I don't have an appreciation for how difficult making these safety updates might be ----- but ----- Van's has identified a structural area in several RVs which, if unrepaired/upgrded, may compromise the safety of the affected airplanes and the lives of those who ride in it.

Can you predict that you will not ever reach or exceed V-NE or severe weather or wake turbulence, etc? If that spar fails, you're dead and so are the people on the ground that your plane hits. Yeah, it' a pain in the ##s to do the safety upgrade but I'd do it so that I could sleep better at night and fly without reservation. $51.00 and a lot of work - it's worth it in my opinion.
 
A lot of different thoughts on the subject. Mine goes like this. IF, the worst happens, and people die, there will be a lot lawyers in line to make some money. Fast forward to the court room, my family on the witness stand, question from the lawyer, the manufacture discovered a fault in the design and issued a SB, and the NTSB blames the HS, did your husband comply with the bulletin, no, the jury hears this and or the judge decides a % of reasonable compensation. Ok, you owe 20% of the 5 million dollar lawsuit awarded. Or it could be worse??.
 
Yeah, its a tough call. I've seen the paint job you did on your tail group. I think I know why you are hedging on doing the SB proactively?the paint job you did is beautiful?not to mention time consuming and expensive. However, I think this SB will nag at you all the time unless you comply with it. In light of the accident last year (not making any assumptions or speculation) I would conform with any SB that involves potential cracking in the tail group. Yes it will be pain in the butt to comply with but you will not ever have to wonder about the structures integrity.
Based on an approximate 10-15% reported crack rate among respondents to a recent thread there is a very good chance you will be addressing it at some point anyway. Better to do it before flying rather than while flying. Just my two cents :(.
 
My plan

I am doing the SB mod on the spar because of Scott's post #277 of the long thread. Will be interesting drilling and riveting those few rivets in the structure. I don't plan to do anything on the hinge bearing SB except be certain that the jam nuts are tight and use torque seal as usual.
 
aarvig said:
However, I think this SB will nag at you all the time unless you comply with it.
Click to expand...

On the other hand, read the SB carefully. It says to inspect - if no cracks, inspect again in a year. By doing no repair (if you have no cracks) you have complied with the service bulletin. Of course logic doesn't always win in a jury trial.

Just to keep it in perspective.

There are risks with every option, including doing the repair. If I hadn't built the stab, I'd incorporate the change. If it was hanging on the wall, I'd take a very, very close look at the polishing job I had done in that area and might make a decision based on that.

But in the end, if you have inspected and found no cracks, you have complied with the SB.
 
bret said:
did your husband comply with the bulletin?
Click to expand...

According to the service bulletin, if you perform the inspection you have complied with the bulletin. Vans could have advised that the repair be made "before further flight" but did not do this.

I would like to see Scott weigh in on this topic. It is an important question.
 
Ironflight said:
On the other hand, read the SB carefully. It says to inspect - if no cracks, inspect again in a year. By doing no repair (if you have no cracks) you have complied with the service bulletin. Of course logic doesn't always win in a jury trial.

Just to keep it in perspective.

There are risks with every option, including doing the repair. If I hadn't built the stab, I'd incorporate the change. If it was hanging on the wall, I'd take a very, very close look at the polishing job I had done in that area and might make a decision based on that.

But in the end, if you have inspected and found no cracks, you have complied with the SB.
Click to expand...

Good point Paul. Instead of saying comply, maybe I should have said perform. It will nag at you unless you perform the SB. However, another good point you make is that there are risks in doing the repair as well. Drilling out all those rivets could create a whole new problem. You have to weigh the options. Me, I would do it since the plane isn't assembled.
 
Mine (all emp) is hanging in the basement begging to be installed. I am going to wait until the dust settles, procure the kits to be prepared, then decide. I have lots more work to do for flight now and that, personally, is not critical to flight for me. The reason for parts, is if inspection is the path, then when the crack is found, I will know the parts won't delay repair. Sometimes stuff changes, so having the parts while the flow is going is just cheap insurance. Like Paul says, I WILL polish, regardless of path.

The may issue may be finding them in 10 or 20 years!!
 
aarvig said:
Good point Paul. Instead of saying comply, maybe I should have said perform. It will nag at you unless you perform the SB. However, another good point you make is that there are risks in doing the repair as well. Drilling out all those rivets could create a whole new problem. You have to weigh the options. Me, I would do it since the plane isn't assembled.
Click to expand...

When you notate in the logbook you should state how you complied with the SB.
Example:

C/W SB XXX dated xxxx by inspection, no cracks noted at this time. Re-inspect due at next annual inspection.
or:
C/W SB XXX dated xxxx by installation of doublers HS-XXXX and Rib Flange angles. This repair is considered terminating action.
 
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I'm actually pretty glad the front horizontal spar bulletin came up.

Turns out my hs702 spars don't even have the relief notches!

I looked at my plans and went though the instructions to see where I missed the callout to add the notches and can't find it anywhere. We're the parts pre notched and somehow mine weren't?

Anyway, I'll be tearing it apart, adding the notches and the reinforcement. :(
 
If you don't have the notches, there's no reason to add them.
The key is that the inside corners are rounded and smooth.
 
After taking mine apart and looking at it, the hole structure is real wobbly without the front angles in there, then look and see what is holding the front of the HS to the fuse? I see 4 rivets on HS-714 per side. On sheet metal! Yes there are four more inboard, but on a single plane of thin sheet. So looking at the SB, with the Plates installed, I see the upper and lower angles being tied together and making this a LOT stronger. Just imagine playing around practicing stall recovery or aerobatics, and imagine the dirty buffets of air impacting the bottom of the HS trying to rip out those 4 rivets! Scary stuff! I am glad my kit plane manufacture brought this to our attention!
 
bret said:
After taking mine apart and looking at it, the hole structure is real wobbly without the front angles in there, then look and see what is holding the front of the HS to the fuse? I see 4 rivets on HS-714 per side. On sheet metal! Yes there are four more inboard, but on a single plane of thin sheet. So looking at the SB, with the Plates installed, I see the upper and lower angles being tied together and making this a LOT stronger. Just imagine playing around practicing stall recovery or aerobatics, and imagine the dirty buffets of air impacting the bottom of the HS trying to rip out those 4 rivets! Scary stuff! I am glad my kit plane manufacture brought this to our attention!
Click to expand...

If all the bending load in each panel of the horizontal stab was truly being carried by just 4, 1/8 " rivets on each side, the stab would have never passed the static load testing that has been done on it (so obviously it is not).

Also, the flight loads on a horizontal stab are actually in the downward direction. In normal flight the horizontal stab is pushing down on the tail to counteract the nose down pitching moment induced by the wing. In a high speed, high G pitch up, the down force is quite high (way more than any "dirty buffets of air impacting the bottom of the HS" would be).

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.
 
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Thank you for your time being involved here, we are greatly apreciate of that. I know that the rear spar is very strong and can handle the load, but, say in a full elevator up deflection, isnt the bottom front of the HS going to be experiencing wind from the the bottom, pulling it away from the fuse?
 
bret said:
Thank you for your time being involved here, we are greatly apreciate of that. I know that the rear spar is very strong and can handle the load, but, say in a full elevator up deflection, isnt the bottom front of the HS going to be experiencing wind from the the bottom, pulling it away from the fuse?
Click to expand...

Wouldn't that make the nose go down, with forces on the bottom - - what does your flight training say for balance of loads?

Logic is better when using balance of forces and real numbers. That is why there are several courses in statics and dynamics for this understanding.
 
Ok the hamster cage is spinning and I am getting way over my head as far as theory and what not, but, imagine traveling in static trim and at maneuvering speed, pull full up with the elevator, which will put full down force on the HS REAR spar, which then causes the angle of attack of the wing to go to?say?15 degrees relative to the flight path. Isn?t the HS going to experience the same 15 deg of airflow hitting the bottom leading edge of the HS? Just a question, like I said I am no expert here :)
 
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