Alaska Gear Company Expands PMA In Response To Potential Piper Rudder AD

Alaska Gear Company has a deep rooted commitment to backcountry flying and the aircrafts that make that possible. The potential Piper Rudder AD has been thoroughly discussed and debated. Regardless of the outcome we are always looking to further support the aviation community and provide the components needed to keep these vintage bush planes in the air flying safely. 

In anticipation of this directive, our engineering department has devoted resources to expand the approved models list of our PA-18 Piper Rudder PMA to include rudders for similar aircraft also affected by the AD. We are ramping up production in response the perceived upcoming demand to ensure the affected aircraft can be supplied with the required fixes to remain airworthy at a reasonable cost. 

Eligible Models For PMA Approved Airframes Alaska Rudders

PA-18

PA-18AS "125"

PA-18S "150"

J5A-80

PA-18S

PA-18 "135" (Army L-21B)

PA-18AS "150"

J5B

PA-18 "105" (Special)

PA-18 A"135"

PA-15

J5C

PA-18S "105" (Special)

PA-18 S"135"

PA-16

PA-14

PA-18A

PA-18 AS “135"

PA-16S

PA-12

PA-18 "125" (Army L-21A)

PA-18 "150"

PA-17

PA-12S

PA-18S "125"

PA-18A "150"

J5A

 
Single-engine plane on grassy airstrip.

What is the Piper Rudder AD?

There has been a lot of confusion regarding this topic, let's eliminate some of the biggest questions first.

Is there an airworthiness directive out regarding the Piper rudders?

Not yet, there is, however, a Notice of Proposed Rulemaking (NPRM) released by the Federal Aviation Administration and Department of Transportation on October 6th, 2023.

What does the proposal say?

The FAA has put forward a proposal to adopt a new airworthiness directive (AD) that would affect select aircraft, specifically older models of Piper airplanes.

Following the proposed AD, affected aircraft would be required to replace their rudder posts made from 1025 carbon steel with a rudder post made from 4130N low-alloy steel.

The administration hopes that this change will improve the safety and continued airworthiness of these aircraft.

When will the proposal go into effect?

Currently, there is an open dialogue taking place on this matter until February 24th 2024. Pilots and aircraft owners are encouraged to voice their opinions and share their reasons for either supporting or opposing the idea with the administration.

If passed, compliance time would be within 2-5 years after the AD's effective date depending on the aircraft model.

Why did this happen?

This proposed AD is a direct response to two non-fatal accidents.

The first accident involved a Piper PA-12 in Anchorage, Alaska, on June 8, 2020. The second accident was with a Piper PA-14 in Anchorage, Alaska, on July 23, 2021.

In June 2022, the NTSB released a report titled:

"Structural Failure of Piper Part Number 40622 Rudder Posts Made of 1025 Carbon Steel", and in this report, they detailed the accidents and the aviation safety concerns with 1025 carbon steel rudders on Piper aircraft.

Evidence photo of rudder post failure from NTSB report

According to the report:

"—a float-equipped Piper PA-12 airplane, N3188M, sustained substantial damage when its rudder structurally failed in flight about 8 miles north of Anchorage—the flight instructor and private pilot receiving instruction were not injured."

"—a float-equipped Piper PA-14 airplane, N4206H, sustained substantial damage when its rudder structurally failed in flight about 15 miles southeast of Anchorage—the commercial pilot was not injured."

Which Piper aircraft will be affected?

If implemented, the airworthiness directive would impact a significant number of historic Piper aircraft. According to FAA estimates, approximately 30,992 airplanes would be impacted by this proposal.

Airplane Models Affected

  • J5A (Army L-4F), J5A-80, J5B (Army L-4G), J5C, AE-1, HE-1 PA-14 PA-12, PA-12S J3C-40, J3C-50, J3C-50S, J3C-65, J3C-65S, PA-11, PA-11S
  • J3F-50, J3F-50S, J3F-60, J3F-60S, (Army L-4D) J3F-65, J3F65S, J3L, J3L-S, J3L-65 (ARMY L-4C), J3L-65S 
  • J4, J4A, J4A-S, J4E (ARMY L-4E) Piper J4F, PA-16, PA-16S, PA-17
  • PA-18, PA-18S, PA-18 “105” (Special), PA-18S “105” (Special), PA-18A, PA-18 “125” (Army L-21A), PA-18S “125”, PA-18AS “125”, PA-18 “135” (Army L-21B), PA-18A “135”, PA-18S “135”, PA-18AS “135”, PA-18 “150”, PA-18A “150”, PA-18S “150”, PA-18AS “150”, PA-19 (Army L-18C), PA-19S
  • PA-18A (Restricted), PA-18A “135” (Restricted), PA-18A “150” (Restricted) 
  • PA-20, PA-20S, PA-20 “115”, PA-20S “115”, PA-20 “135”, PA20S “135”
  • PA-22, PA-22-108, PA-22-135, PA-22S-135, PA-22-150, PA22S-150, PA-22-160, PA-22S-160

3 Place Super Cub on gravel bar.

The Danger of 1025 Carbon Steel

This matter should not be taken lightly by aircraft owners, the decision to keep a 1025 carbon steel post can prove dangerous, as it is susceptible to fatigue, corrosion, and fractures. While these issues may not arise immediately, over time the equipment will eventually fail.

Before 1974, Piper model airplanes were outfitted with rudder posts made of 1025 carbon steel. Following incidents involving broken rudders, starting in 1974 the rudder posts were made from 4130N low-alloy steel.

Today, most rudders certified by parts manufacturers are equipped with low-alloy steel posts.

How You Can Prepare Your Piper Aircraft

It is always wise to proactively address potential issues and explore available options to ensure the safety of your aircraft.

Airframes Alaska has been well known for its manufacturing of Super Cub Control Surfaces including Piper Rudders, Vertical Fins, Stabilizers, and Elevators. We recently expanded our PMA to a wider range of Piper Models outside of just the PA-18 Super Cub models such as vintage PA-12s, PA-14s, J5’s, and more. 

After a decade of dedicated craftsmanship, the Airframes Alaska Rudder offers:

  • Forged from premium 4130 Chromoly Steel
  • FAA/PMA certified for safety assurance
  • Resistant to corrosion, ensuring longevity up to 50 years
  • Built tough for heavy-duty use
  • Complete with Brass Bushings for maximum functionality

We recommend watching our video that features this rudder:

Have Concerns?

If you want to voice your concerns to the FAA regarding this matter you can check out this November 2023 extension, on it you'll find contact information to reach out and express your thoughts on the new directive.

Takeaway

We understand that this can be a sensitive topic for aircraft owners, but it is important to prioritize safety in our discussions about alternative solutions to meet the proposed standards. The goal is to come to agreements that work for all parties involved.

The FAA and DOT have put considerable thought and consideration into the proposal. The issue of carbon steel rudder failures has been ongoing since the 1970s, with the NTSB reporting multiple incidents as far back as 1979.

As pilots and aircraft owners, we must always prioritize safety in our decision-making process.

We wish you all the best and hope you stay safe, and stay airworthy.



PA-18 Rudder

PA-18 Vertical Fin

PA-18 Round Elevator

PA-18 Round Stabilizer


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