Checking a Piper Stabilator

WannFly

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Priyo

while all control surfaces are checked in preflight, i had no idea the entire stabilator is held by 2 bolts
 
Yessir. Very important fix. I just had to put stab bushings and bolts into a very nice (low time) Archer due to forward and aft slack. It’s perfect now.
It’s no small job either! Might not be so bad if you just swap bolts but bushing too, that’s a lot of work.
 
I disagree with the way he’s saying to check for play. It doesn’t hurt to check it that way but you typically won’t find the slack like that. Piper MM doesn’t allow any movement.
The one I just repaired had zero up and down movement, but obvious forward and aft play! You can check it by yourself, but if want a better feel for the extent of the slack get a second person. One person on each stab tip. Push forward while the other is pulling aft. Not hard, just a couple pounds of pressure each is plenty.
See the attachment for the movement I’m describing.
 

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Had that exact issue with my archer, replaced both bushings in my annual. Not cheap!
 
To be clear, this is not accurate for to all Pipers that have stabilators. It is correct that none should move. On a PA24, the stabilator bearing block is held on with 4 large bolts (2 per side) and the stabilator is mounted to the torque tube using 2 1/4" stainless bolts on each side.


while all control surfaces are checked in preflight, i had no idea the entire stabilator is held by 2 bolts
 
Had that exact issue with my archer, replaced both bushings in my annual. Not cheap!

May I ask roughly how much total for parts and labor?
 
It’s a close tolerance bolt. P/N 402-680 is what we used. 2 total holding the stab at the pivot point (PA-28-181 Archer II). The bolts were cheap, bearings or “bushings” as I called them were the bulk of the parts price.
Most the wear appeared to be in the bolts rather than the bearings. You won’t really know until you pull everything apart. Best to replace both bearings and bolts while your in there. Made a huge difference. Super smooth and zero play afterwards.
 

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May I ask roughly how much total for parts and labor?
The stabilator bearings (2) were $83.40 each. I couldn't begin to guess what the labor came to as they lumped it into a bunch of stuff they had to do with the elevator trim. But I am guessing a couple of grand because the entire stabilator had to come off. It definitely was not just two bolts.
 
Sounds expensive!! Way cheaper than not replacing in time I guess
 
Sounds expensive!! Way cheaper than not replacing in time I guess
Sounds expensive!! Way cheaper than not replacing in time I guess
Well, they said that they would let them slide until next annual but they were into the tail anyway so it was a "might as well" thing. This was the first annual for this plane since I bought it so I told the A&P's to go through it from one end to the other and fix anything questionable. It took over a month but now I am sure it's 100%, well worth the money for peace of mind.
 
Thanks. Was just trying to gauge other rates against what I charged for that same job.
 
Well, they said that they would let them slide until next annual but they were into the tail anyway so it was a "might as well" thing. This was the first annual for this plane since I bought it so I told the A&P's to go through it from one end to the other and fix anything questionable. It took over a month but now I am sure it's 100%, well worth the money for peace of mind.
LOLOLOLOL
100% ?!?!?!
This your first aircraft, I'm assume?

No matter how much work I do on my sweet baby, she always finds something else for me to replace...
 
LOLOLOLOL
100% ?!?!?!
This your first aircraft, I'm assume?

No matter how much work I do on my sweet baby, she always finds something else for me to replace...
Well 5 guys working on her for over a month to the tune of 12 grand got her pretty close to 100%. Like I said, nothing major, just a lot of little things but they went through it from prop to trim tab so confidence is high.
 
the entire stabilator had to come off. It definitely was not just two bolts.

You’re right. It’s not “just 2 bolts” to accomplish the whole job! All sorts of stuff has to come off to get the stab dropped down and out of the way to get to the 2 bolts and bearings causing the problem. Everything around them has to be taken apart, including the trim drum assembly. The cables have to be blocked to prevent coming off the pulleys up front, etc. You can see the wooden cable blocks in one of my pics. It took me and another A&P 4.5 hours nonstop. Then it took another hour just to clean up shop and get back organized with all the paperwork.
 
It took over a month but now I am sure it's 100%, well worth the money for peace of mind.
FYI: if you're using the "100%" to indicate aircraft airworthiness keep in mind airworthiness is not a finite condition mainly due to it is highly subjective to the person determining that airworthiness. At best your $12k bought you what the 5 mechanics determined to be airworthy items or not, unless you were also an integral part of that determination. So if you put your "100%" aircraft up for sale today and the buyer's A&P finds "25%" of the aircraft unairworthy it doesn't always mean the previous 5 A&Ps "missed" something. However, regardless who determines the airworthiness of the aircraft, you as owner are the one held responsible for the condition of the aircraft.
 
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That is not that expensive in grand scheme of things. b/w is this anyway related to AD 2013-2-13?

It could have easily taken all day. We were very prepared and efficient for once! I also took it for a short test flight afterwards just to make sure all was well.

I’m sure you could identify this wear item on the AD you mentioned but we found the it by pushing and pulling on the stab. Seems like that AD is primarily for the identification of cracks and corrosion. I suppose it would be a good time to check for those items with everything apart. Most mechanics are looking for that stuff anytime they into something like this.
 
FYI: if you're using the "100%" to indicate aircraft airworthiness keep in mind airworthiness is not a finite condition mainly due to it is highly subjective to the person determining that airworthiness. At best your $12k bought you what the 5 mechanics determined to be airworthy items or not, unless you were also an integral part of that determination. So if you put your "100%" aircraft up for sale today and the buyer's A&P finds "25%" of the aircraft unairworthy it doesn't always mean the previous 5 A&Ps "missed" something. However, regardless who determines the airworthiness of the aircraft, you as owner are the one held responsible for the condition of the aircraft.
I was heavily involved and I directed them to correct any discrepancies they found. If we only corrected enough to make it airworthy, I could have got off for a couple of grand but we opted to replace anything that was even questionable. I am very confident that everything is back to factory standards. Could we have missed something? Sure but we went through it very thoroughly and I have no trepidation putting my family and friends in that bird.
 
If we only corrected enough to make it airworthy, I could have got off for a couple of grand but we opted to replace anything that was even questionable.
As long as you understand by this comment that this is a classic example of the subjectivity of airworthy. Technically, there should be no difference between airworthy and "factory standards." Good luck.;)
 
on a completely different note... is there a service from Piper where you can take the plane to them and they will make it back to factory standards, take care of all AD / SB etc? like a OH that you can do with the motor?
 
I recently completed (for a customer) a prebuy evaluation, a ton of maintenance, and CFI,II work in a PA-28-181 Archer II. I’ve taken it in and out the the avionics shop, engine shop, interior, paint work, etc. Lots of work here! Great little airplane. Very advanced package. The stab check was one of our biggest finds. Another was verification and replacement of flexible flammable hoses forward of the firewall. Mechanics had been signing those old brittle hoses off for years. Some of the dates went back to the early 90’s. The oil cooler hoses were not in compliance with the AD that had been signed off. Check your dates. Mechanics can point to all sorts of documents to justify replacing or not replacing. Most information suggests 5, 7, or 10 years. None stay on my personal plane beyond 10 years, less depending on conditions.
 
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This looks photoshopped! There's a distinct lack of snow blowing horizontally across the landscape in the direction of Minnesota. :p

...Another was verification and replacement of flexible flammable hoses forward of the firewall. Mechanics had been signing those old brittle hoses off for years. Some of the dates went back to the early 90’s. The oil cooler hoses were not in compliance with the AD that had been signed off. Check your dates. Mechanics can point to all sorts of documents to justify replacing or not replacing. Most information suggests 5, 7, or 10 years. None stay on my personal plane beyond 10 years, less depending on conditions.

Hoses are interesting. Seems a common item to ignore as you noted.
Last year I finished a 2 year program to replace all the hoses on the Aztec. Found one of the hydraulic hoses that was original Piper installed 40 years ago at time of manufacture. The 1996 Husky I bought had original hoses and fuel line from the gascolator to the carb was leaking inside the firesleeve. All of them rock hard.
 
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Yep, I found original flexible brake hoses from piper 1979. These were the long ones that go from the calipers up to the wing spar. Rock hard brittle and leaking. I yanked ALL old hoses at one time. I measured, tagged, bagged, and sent all to the hose shop for duplication.
 
Yep, I found original flexible brake hoses from piper 1979. These were the long ones that go from the calipers up to the wing spar. Rock hard brittle and leaking. I yanked ALL old hoses at one time. I measured, tagged, bagged, and sent all to the hose shop for duplication.

Well, once again I make the observation that these Pipers and Cessnas were never meant to be around as long as this.
They were a mass produced airplane in their day, and pilots were supposed to keep upgrading to higher performance models in the manufacturer's line up by trading up.
Taking apart stabilators to replace bushings and such was probably something not really expected to be needed in the life of the airplane originally.
 
This looks photoshopped! There's a distinct lack of snow blowing horizontally across the landscape in the direction of Minnesota. :p
ha ha ha. its a odd winter here. we have some snow on the ground here and in MN, i was in SD last sunday... no snow anywhere to be found on the ground...
 
I gave the Archer’s stabilator a wiggle during pre-flight this afternoon and it was nice and tight <knocks on wood>.

Thanks for this thread and bringing this to our attention. :)
 
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