FAA issues an Airworthiness Concern Sheet and asks for information regarding
Make: Piper/FS2003 Corp
Model / Series: J-5A, J-5B, J-5C, J-5D, AE-1, HE-1, PA-12, PA-12S, PA-14, PA-16, PA-18, L-21, PA-20, and PA-22
Serial Numbers: All
Reason for Airworthiness Concern: In flight failure of rudder just above the upper hinge.
From the FAA:
Recently an accident occurred where the rudder on a PA-12 failed in flight. The airplane was a seaplane equipped with a 160 hp Lycoming
O-320 engine. The original tail surfaces had been replaced with PA-18 tail surfaces in accordance with a Supplemental Type Certificate
(STC). The broken upper part of the rudder post broke just above the top hinge and the upper part of the rudder folded over the tail brace
wires in such a way that rudder control was severely limited and as to effectively create an additional horizontal tail, driving the tail down
and the nose up. It was possible for the senior flight instructor to control the airplane in pitch, but required a lot of the available elevator
deflection to do so. By dropping the water rudders, some directional control was established and the airplane was able to return to base and
land, but with difficulty.
We would appreciate input on the following question regarding the most appropriate actions to take:
1. What other occurrences have been observed of rudders failing?
2. What information can you provide about possible causes for the failures?
3. What solutions might be available and effective?
4. What reports of vibrations have people observed in the rudder and is there any correlation with the presence or absence
of a strobe or beacon on the top of the rudder?
Download Entire ACS here https://www.piperflyer.org/knowledge-base/aviation-alerts/item/download/393_7e339cc47971cbf79b35e3e7032f1e63.html
