93-10-06: Corroded Wing Lift Struts or Cracked Forks

93-10-06 PIPER AIRCRAFT CORPORATION: Amendment 39-8586. Docket No. 90-CE-21-AD. Supersedes AD 77-03-08, Amendments 39-2833 and 39-3269, and AD 81-25-05, Amendment 39-4276. Applicability: The following model and serial number airplanes, certificated in any category: Models Serial Numbers J-2 Series 500 through 1975 J-3, NE-1, and L-4 All serial numbers J-4 Series 4-401 through 4-1649 J-5, J-5C, L-14, AE-1, and HE-1 Series 5-1 through 5-1389 PA-11 Series 11-1 through 11-1678 PA-12 Series 12-1 through 12-4036 PA-14 Series 14-1 through 14-523 PA-15 15-1 through 15-388 PA-16 16-1 through 16-736 PA-17 17-1 through 17-215 PA-18 and PA-18A 18-1 through 18-8309025, 1809001 through 1809032, and 1809034 through 1809040 PA-19 19-1, 19-2, and 19-3 PA-20 Series 20-1 through 20-1121 PA-22 Series 22-1 through 22-9848 PA-25 Series 25-1 through 25-8156024 Compliance: Required as indicated, unless already accomplished. To prevent in-flight separation of the wing from the airplane caused by corroded wing lift struts or cracked forks, accomplish the following: (a) Within the next 30 calendar days after the effective date of this AD or within two calendar years after the last inspection accomplished in accordance with AD 77-03-08, whichever occurs later, remove the wing lift struts in accordance with the applicable maintenance manual, and accomplish the actions of either paragraph (a)(1), (a)(2), (a)(3), or (a)(4) below: (1) Inspect the wing lift struts for corrosion in accordance with the instructions in either Piper Service Bulletin (SB) No. 528D, dated October 19, 1990, or Piper SB No. 910A, dated October 10, 1989, as applicable. NOTE 1: Inspection methods such as x-ray or boroscope may be utilized provided they are approved as an alternative method of compliance in accordance with the procedures specified in paragraph (f) of this AD. (i) If corrosion is not found, reinspect at intervals not to exceed 2 calendar years. (ii) If corrosion is found, prior to further flight, accomplish either paragraph (a)(2), (a)(3), or (a)(4) of this AD. (iii) If holes have been drilled in sealed struts to attach cuffs, door clips, or other hardware, reinspect the wing lift struts at intervals not to exceed 2 calendar years. (2) Install original equipment manufacturer (OEM) part number wing lift struts or FAA-approved equivalent wing lift struts that have been inspected and found airworthy. Inspect these wing lift struts as specified in paragraph (a)(1) of this AD at intervals not to exceed 2 calendar years. (3) Install new sealed wing lift strut assemblies (part numbers as specified in Piper SB No. 528D or Piper SB No. 910A) or Univair FAA Parts Manufacturer Approved (PMA) equivalent wing lift strut assemblies on each wing. NOTE 2: These new sealed wing lift strut assemblies contain both a sealed strut and redesigned fork. (4) Install F. Atlee Dodge wing lift struts in accordance with the instructions to Supplemental Type Certificate (STC) SA4635NM, and inspect the wing lift struts as specified in paragraph (a)(1) of this AD at intervals not to exceed 5 calendar years. (b) Within the next 100 hours time-in-service (TIS) after the effective date of this AD or within 500 hours TIS after the last inspection accomplished in accordance with AD 81-25-05, whichever occurs later, remove the wing lift strut forks and accomplish the actions of either paragraph (b)(1), (b)(2), (b)(3), or (b)(4) below: (1) Inspect the wing lift strut forks using currently approved magnetic procedures. (i) If no cracks are found, reinspect at intervals not to exceed 500 hours TIS and replace the lift strut forks at the time specified in either paragraph (b)(1)(i)(A) or (b)(1)(i)(B) below: (A) If airplane is or has been equipped with floats, upon the accumulation of 1,000 hours TIS. (B) If airplane has never been equipped with floats, upon the accumulation of 2,000 hours TIS. (ii) Replacement parts shall be of the same part number of the existing part and shall be manufactured with rolled threads or an FAA-approved equivalent part. Lift strut forks manufactured with machined (cut) threads shall not be utilized. (iii) If cracks are found, prior to further flight, install forks as specified in either paragraph (b)(2), (b)(3), or (b)(4) of this AD. (2) Install OEM part number wing lift strut forks that have been inspected and found airworthy. Reinspect using currently approved magnetic procedures at intervals specified in paragraph (b)(1) of this AD. (3) Install new sealed wing lift strut assemblies (part numbers as specified in Piper SB No. 528D or Piper SB No. 910A) or Univair FAA PMA equivalent wing lift strut assemblies on each wing. The installation of these assemblies may have already been accomplished in accordance with paragraph (a)(3) of this AD. (4) Install F.Atlee Dodge wing lift strut forks in accordance with the instructions to STC SA4635NM. (c) The installation of new sealed wing lift strut assemblies as specified in paragraphs (a)(3) and (b)(3) of this AD is considered terminating action for the repetitive inspection requirement of this AD. (d) The installation of F. Atlee Dodge wing lift strut forks as specified in paragraph (b)(4) of this AD is considered terminating action for the repetitive inspection requirement of paragraph (b)(1) of this AD. (e) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (f) An alternative method of compliance or adjustment of the initial or repetitive compliance times that provides an equivalent level of safety may be approved by the Manager, Atlanta Aircraft Certification Office, 1669 Phoenix Parkway, Suite 210C, Atlanta, Georgia 30349. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta Aircraft Certification Office. NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta Aircraft Certification Office. (g) The inspections required by this AD shall be done in accordance with Piper Service Bulletin No. 528D, dated October 19, 1990, or Piper Service Bulletin No. 910A, dated October 10, 1989, as applicable. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from the Piper Aircraft Corporation, 2926 Piper Drive, Vero Beach, Florida 32960. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (h) This amendment (39-8586) supersedes AD 77-03-08, Amendments 39-2833 and 39-3269, and AD 81-25-05, Amendment 39-4276. (i) This amendment becomes effective on July 9, 1993.