AD 2003-24-07 Airworthiness Directives; The New Piper Aircraft, Inc. Models PA-31, PA-31-300, PA-31-325, PA-31-350, PA-31P, PA-31T, PA-31T1, PA-31T2, PA-31T3, and PA-31P-350 Airplanes

Makes named: piper. Read the applicability below — it usually turns on serial or part numbers too.

(c) This AD affects the following airplane models and serial numbers that are certificated in any category:   Model Serial numbers PA-31, PA-31-300, PA-31-325 31-2 through 31-8312019 PA-31-350 31-5001 through 31-8553002 PA-31P 31P-1 through 31P-7730012 PA-31P-350 31P-8414001 through 31P-8414050 PA-31T 31T-7400001 through 31T-8120104 PA-31T1 31T-7804001 through 31T-1104017 PA-31T2 31T-8166001 through 31T-1166008 PA-31T3 31T-8275001 through 31T-5575001

(e) To address this problem, you must accomplish the following:   Actions Compliance Procedures (1) Install an inspection hole in the rudder skin for the rudder torque tube assembly; OR instead of installing an inspection hole, use the tooling hole in the rudder bottom rib. You may enlarge the diameter of the tooling hole no more than 0.25 inches to facilitate inspection and corrosion treatment Within the next 150 hours time-in-service (TIS) after February 9, 2004 (the effective date of this AD), unless already accomplished Install an inspection hole per The New Piper Aircraft, Inc. Service Bulletin No. 1105A, dated September 22, 2003. Protect bare metal per Section 8, FAA Advisory Circular (AC) 43.13-1B. (2) Visually inspect the rudder torque tube and associated ribs for corrosion Before further flight after the installation required in paragraph (e)(1) of this AD and thereafter at intervals not to exceed 12 calendar months Follow The New Piper Aircraft, Inc. Service Bulletin No. 1105A, September 22, 2003. (3) If you find corrosion damage: (i) Replace the rib/rudder torque assembly; OR (ii) Repair the damaged torque tube using an FAA-approved repair design Before further flight after any inspection required in paragraph (e)(2) of this AD where corrosion damage is found Follow The New Piper Aircraft, Inc. Service Bulletin No. 1105A, dated September 22, 2003. Repairs must address items in paragraph (f) of this AD and may be approved per FAA Order 8300.10 (Volume 2, Chapter 1), Airworthiness Inspector's Handbook. (f) All repairs must address the following: (1) Detect hidden corrosion damage: (i) In the faying surface between the rudder ribs and torque tube assembly attachments. (ii) Inside the bore of the torque tube. (2) Establish procedures for removing corrosion or for corrosion prevention of repaired parts. Advisory Circular (AC) 43.13-1B Acceptable Methods, Techniques, and Practices-Aircraft Inspection and Repair, and AC 43-4A, Corrosion Control for Aircraft, provide resources for establishment of these procedures. (3) For repairs involving material removal without reinforcement: Define a clear, accurate, and complete description of negligible damage limits. Note that acceptable amounts of material removal may be location-dependent. Higher-stressed areas will be less tolerant of material removal. (4) For all repairs involving reinforcement: A clear, accurate, and complete description of the repair design must be established per 14 CFR part 21.31. (5) Verify that all repairs follow Subpart C—Strength Requirements and Subpart D—Design and Construction of Civil Aviation Regulations (CAR) 3, dated May 15, 1956 (the original certification basis for the Piper PA-31 Series as shown in type certificate data sheets A8EA and A20SO).

(d) This AD is the result of reports of rudder tube corrosion. The actions specified by this AD are intended to detect and correct corrosion in the rudder torque tube assembly and rudder rib, which could result in failure of the rudder torque tube. This failure could lead to loss of rudder control.

(b) None.