Piper Rudder Airworthiness Directive Issued

[Steve Pierce]

Well as of midnight tonight despite the efforts of a lot of people here at SuperCub.org, ShortWingPipers.org, AOPA, EAA and the Short Wing Piper Club the FAA decided to issue an Airworthiness Directive against all of our aircraft's rudders. I can tell you that no one is happy about it but it is what it is. You can read the entire document here.
https://public-inspection.federalregister.gov/2025-02528.pdf

Here is the compliance schedule:

Category I Airplanes:
Airplanes having both
a rudder post mounted beacon light and a
150 or greater horsepower (hp) engine
installed.
Compliance Time:
Within 2 years after the effective date of
this AD.

Category II Airplanes: Airplanes having
either a rudder post mounted beacon light or
a 150 or greater hp engine installed.
Compliance Time:
Within 3 years after the effective date of
this AD.

Category III Airplanes: All airplanes not in Category I or Category II that do not have a rudder
post mounted beacon light and have an engine less than 150 hp and greater than 100 hp installed.
Compliance Time:
Within 5 years after the effective date of
this AD.

Category IV Airplanes: All airplanes not in Category I, II, or III that do not have a rudder post
mounted beacon light and have an engine of 100 hp or below installed.
Compliance Time:
Within 10 years after the effective date of
this AD.

A little insight into the availability, Univair has a few in stock as does Dakota Cub, Alaska Gear Company has 9 in stock as of 2 pm CST 2-13-25. The issue is that the vendor that made the tail nav light bracket for Univair suddenly announced they would no longer make the brackets. I had a call from Jim Dyer the president of Univair a few months ago about this issue. As of our conversation today a new vendor has been procured and they are expecting a batch of brackets at the end of this month. The issue is that not only does Univair use these brackets but so does Dakota Cub. Alaska Gear Company has started making their own brackets. I guess the good thing is that the compliance time has been spread out so there is hopefully not a mad rush on rudders.

From Piper Service Bulletin SB 1379B

The affected aircraft will fall into one of the following categories:
• For aircraft with an airworthiness certificate issued prior to June 3rd, 1974, these aircraft were delivered from the factory with a rudder post made from 1025 steel. If a complete service history exists and it can be confirmed that the original rudder is still installed, proceed to Part II.
• For aircraft with an airworthiness certificate issued on or after June 3rd, 1974, these aircraft were delivered from the factory equipped with a rudder post made from either 1025 steel or 4130N steel. At owner/operator discretion, proceed to Part I. Otherwise, proceed to Part II.
• Aircraft equipped with a rudder of unknown or incomplete service history may have a rudder post made from either 1025 steel or 4130N steel. For these aircraft, the type of steel alloy used in the manufacture of the rudder post cannot be determined by visual inspection. At owner/operator discretion, proceed to Part I. Otherwise, proceed to Part II.

Also, all PMA'd rudders have been made from 4130 so if your rudder has been replaced with a new one it should be 4130.

 

[dgapilot]

I already have my AMOC request written, will submit it tomorrow.

 

[bob turner]

I will be doing mine this month. I have never done one before - the AD seems to invite them, and does not address any strength computations for internal reinforcement. It just says "too many different rudders - we cannot envision a fix that will work for all of them."

 

[aktango58]

help me,

Many planes have had rudders replaced recently? Do they need to comply with the AD for a 2 year old rudder just like a plane with a 40 year old rudder??

How about experimental birds, or the CC-18? Some run the same rudders... are these exempt since they are not within the 'affected' models but have possibly the EXACT same part?

 

[Steve Pierce]

help me,

Many planes have had rudders replaced recently? Do they need to comply with the AD for a 2 year old rudder just like a plane with a 40 year old rudder??

How about experimental birds, or the CC-18? Some run the same rudders... are these exempt since they are not within the 'affected' models but have possibly the EXACT same part?

Did you read what I posted?

 

[aktango58]

I did. Things don't make sense to me.

I may have missed something. It appears that this is a narrow AD, but I did not see exclusions for new parts and such; also, it appears only Piper products are affected.

I see the three categories, but again, nothing about actual rudder age.

 

[Steve Pierce]

Piper rudders from 1974 and later are 4130 and all PMA'd rudders are 4130. The AD is for 1025 steel rudders.

 

[aktango58]

Thank you, I missed that distinction in my understanding. It appeared that newer 4130 ones still needed inspection, just at different intervals.

 

[Steve Pierce]

No, if you have a 4130 rudder you are golden.

 

[sj]

I split this thread from the "possible" thread since it is now a reality..

sj

 

[btracy]

Do you have to apply for AMOC for every plane? Or will be for all planes if accepted?

 

[dgapilot]

Do you have to apply for AMOC for every plane? Or will be for all planes if accepted?

AMOCS can be issued for each airplane or they can be issued as a blanket AMOC. From the responses in the Final Rule preamble, it didn't sound like they wanted to entertain global AMOCs but there is nothing stopping anyone from requesting them

 

[dgapilot]

My AMOC Request was submitted this morning.

 

[jrussl]

My AMOC Request was submitted this morning.

Thank you for sharing!

 

[jrussl]

It is interesting that the FAA stated this in the AD. Section B-8

"The FAA also anticipates that many operators will reinforce their rudders by using the alternative method of compliance (AMOC) process rather than replacing them. "

This sure looks like they are open to AMOC's.

 

[Foggy]

Piper rudders from 1974 and later are 4130 and all PMA'd rudders are 4130. The AD is for 1025 steel rudders.

I thought 1974 and later would be exempt. The AD says that if your plane is 1974 or later, it could be either 1025 OR 4130, so you still need to do the test to confirm it’s 4130. Do you agree? Mines a 1976 so should be 4130 but I think the AD still applies?

 

[dgapilot]

I thought 1974 and later would be exempt. The AD says that if your plane is 1974 or later, it could be either 1025 OR 4130, so you still need to do the test to confirm it’s 4130. Do you agree? Mines a 1976 so should be 4130 but I think the AD still applies?

I think they are covering all bases, someone could have replaced a rudder on a newer airplane with an older rudder.

 

[BradleyG]

I have a 1979 SC, does the SB AD apply? Does the acid test still have to be accomplished?

The posts concerning 74 and after when compared to SB are somewhat confusing.

 

[twoeightfive]

I have a 1979 SC, does the SB AD apply? Does the acid test still have to be accomplished?

The posts concerning 74 and after when compared to SB are somewhat confusing.

You have to determine if it is 4130 or 1025 still with the nitric acid test. It could be EITHER 4130 or 1025 after June 3rd, 1974. I have a 1976 cub, I'm thinking it should be fine but I won't know for sure until I actually test it since that's the original rudder on mine. I ordered a new one from atlee though anyways since I'm doing fabric this next winter and want all new surfaces.

 

[BC12D-4-85]

How hard would it be to replace just the affected tube with 4130 vs complete new rudder?

Gary

 

[Steve Pierce]

Sean McLaughlin just texted me and updated me that they are now making their own nav light bracket and that they have 9 rudders in stock as of this posting and are continuing to make more. I updated my original post to reflect this new information.

 

[dgapilot]

How hard would it be to replace just the affected tube with 4130 vs complete new rudder?

Gary

The rudder tube is an assembly that consists of the tube, a reinforcement where the bellcrank is attached and the bellcrank. Build that assembly, then insert it into the rudder where you cut the old one out/ You need to cut the welds at each rib and where it attaches to the little tube at the top and bottom. Cutting the old one out is the delicate part of the job as you don't want to destroy the parts that remain. Jig the new rudder tube assembly with the old rudder parts and weld that up, then weld on the hinge bushings in the correct location (again jigged). With all the correct tools and jigs someone that knows what they are doing can likely do it in about 10 - 12 hours. If you never did it and need to build the jigs you can double or triple that time. If you need to pay someone, it is likely cheaper to buy a new rudder, if you are a welder and have the skills and tools and aren't paying for the labor, it is a lot cheaper to do it yourself.

 

[btracy]

Sean McLaughlin just texted me and updated me that they are now making their own nav light bracket and that they have 9 rudders in stock as of this posting and are continuing to make more. I updated my original post to reflect this new information.

Did they design it to accommodate the tail beacon?

 

[Waldo M]

INSTRUCTIONS:


NOTE: Instructions contained within this service bulletin apply only to genuine Piper parts. Piper has no knowledge


of the materials or manufacturing processes used by STC (Supplemental Type Certificate) or PMA (Parts


Manufacturer Approval) holders that manufacture replacement parts for Piper products. Contact the


component manufacturer for guidance.

This is from the Piper Service Bulletin. Univair built my Rudder in 2013. I checked with them and they stated all rudders built and shipped by them since the nineteen seventies are made with 4130 tubing,

Since the A.D. refers to the Piper Service Bulletin for a method of compliance and the bulletin specifically excludes any rudders not manufactured by Piper, It would seem to me that the A.D. is not applicable per the wording of the S. B.

 

[BC12D-4-85]

....If you need to pay someone, it is likely cheaper to buy a new rudder, if you are a welder and have the skills and tools and aren't paying for the labor, it is a lot cheaper to do it yourself.

Thanks for that. Just wondered. Internal sleeve AMOC you suggest is better.

Gary

 

[Steve Pierce]

Also, all PMA'd rudders have been made from 4130 so if your rudder has been replaced with a new one it should be 4130.

Waldo, you are correct.

 

[johnhefley]

Looks like 10 years for my C90 powered J-3.

 

[CFFIY]

Why is the PA-25 not on the list in the AD?

 

[jjdk737]

Why is the PA-25 not on the list in the

"Several commenters, including individuals and the NTSB stated that other airplane
models should be added to the applicability of the proposed AD. The commenters stated that
other airplane models use the same rudder type.
FAA response: The FAA partially agrees. The FAA received a letter from the NTSB
dated November 14, 2023, which identified the Model PA-25 airplane as a missing model in the
applicability of the proposed AD. Piper sold the Model PA-25 airplane type certificate to a
company located in Argentina. Therefore, the state of design for the Model PA-25 airplane is
Argentina. The FAA has transmitted the NTSB’s letter to the National Civil Aviation
Administration of Argentina, which is the civil aviation authority for Argentina. The FAA will
work with the National Civil Aviation Administration of Argentina to assure that this condition
is addressed on the Model PA-25 airplanes.
The FAA has not changed this AD as a result of these comments."

 

[jjdk737]

Since the A.D. refers to the Piper Service Bulletin for a method of compliance and the bulletin specifically excludes any rudders not manufactured by Piper, It would seem to me that the A.D. is not applicable per the wording of the S. B.

Actually, if your plane is listed in the applicability list, the AD is applicable.
You've already remedied the situation by previously installing a rudder with a post made of 4130.
Your maintenance records need an entry that AD 2025-02-11 has been previously accomplished by the installation of a new rudder with a 4130 post material on dd-mm-year. No further action required.

1 reason......this requirement from the AD still applies,
"(2) As of the effective date of this AD, do not install any rudder that is equipped with a
rudder post made from 1025 carbon steel on any airplane".