SERVICE No. 910 A BULLETIN

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Piper Aircraft Corporation Vero Beach, Florida, U.S.A. SERVICE No. 910 A BULLETIN ********************************** : PIPER CONSIDERS : : COMPLIANCE MANDATORY : ********************************** Date October 10, 1989 S (Service Bulletin No. 910A supersedes and voids Service Bulletin No. 910, dated May 15, 1989 and the affected portions of Service Bulletin No. 528B, dated March 10, 1978) This Service Bulletin is divided in two Parts. Check each Part for applicable compliance time, purpose and instructions. SUBJECT: Wing Lift Strut Assembly Inspection/Replacement REASON FOR REVISION: To revise models affected, serial numbers affected, compliance time, purpose, instructions and to add Part II. APPROVAL: The technical contents of this Service Bulletin have been approved by the F.A.A. MODELS AFFECTED: PA-18/18A Series Super Cub NOTE: Includes All Serial No. L-21A, L-21B, & L-18, Seaplane, Agricultural, and Military Versions PA-19 Super Cub PART I SERIAL NUMBERS AFFECTED: 18-1 through 18-8309025, 1809001 through 1809032, 1809034 through 1809040 19-1, 19-2 and 19-3 COMPLIANCE TIME: thereafter. Before next flight and each twelve (12) month period NOTE: If the inspection requirements of Service Bulletins No. 528B or No. 910 have been accomplished within the last twelve (12) months or if the wing lift struts are new and were installed within the last twelve (12) months, inspection is required no later than twelve (12) months after the last inspection or new lift strut installation as the case may be. If the aircraft is new with original lift struts installed, the repetitive inspection begins when the aircraft is twelve (12) months old. (OVER) ATA: 5701 SERVICE BULLETIN NO. 910A PAGE 2 OF 5 PURPOSE: Piper Aircraft has determined that the five (5) year repetitive inspection interval required in Service Bulletins No. 528B and 910 may be inadequate for the timely detection of serious wing lift strut corrosion. This corrosion, if allowed to progress, may lead to failure of the wing lift strut, and the possibility of loss of wing structure integrity. The compliance time for the corrosion inspection and treatment is reduced to an interval not to exceed twelve (12) months from the last inspection or the first use of new lift struts . Initially Piper deems it necessary to replace existing wing lift strut with new sealed wing lift struts at a date not to exceed twenty-four (24) months. (See Part II) Part I of this Service Bulletin provides an inspection an corrosion impediment procedure to detect and treat possible wing lift strut corrosion. INSTRUCTIONS: 1. Remove wing lift struts and accomplish the inspection per inspection procedures on Sketch "A". Caution: All aircraft utilizing "cuffs" at the wing lift strut roots (top and/or bottom) should take extra care in inspection for external corrosion in the areas covered by the cuffs. 2. Inspect forks, clamps, fairleads and jury struts for condition and replace as necessary. All attaching hardware should be replaced. 3. After completion of the inspection procedure, but prior to the corrosion impediment procedure of the wing lift struts, turn each wing lift strut upside down and tap gently. This procedure is necessary to remove any water, debris, or corrosion particles which may have accumulated. 4. Lift strut tubes indicating presence of internal corrosion and which fail the inspection procedure must be replaced with new wing lift struts called for in PART II of this Service Bulletin. Note: Should corrosion be apparent from the outside, (rust pin holes or large rust stains) stru.t must be replaced even if strut passes the inspection procedure. 5. Treat (corrosion impediment) each wing lift strut per the instruction procedure note on Sketch "A". Treatment must coincide with each inspection as outlined in the compliance time above. 6. Lift strut assemblies which have been factory treated with corrosion preventive measures are identified by the installation of a cherry lock rivet installed at the upper (wing attachment) end. 7. Alternate preservative materials: In addition to the "Val oil" and "Lionoil" (preservatives), it is permissible to use the following alternate preservatives- Paralketone, linseed oil or any alternate preservatives that satisfy the requirements of Federal Specification TT-S-1760. NOTE: Upon successful completion of the inspection procedure and treatment, reinstall lift struts on aircraft. · 8. Check aircraft rigging and adjust as necessary, use. Piper Service Memo 19* (attachment A) as required to accomplish the proper rigging. 9. Make an appropriate logbook entry of compliance with this Service Bulletin. *NOTE: See SERVICE MEMO No. 19, "RIGGING PROCEDURE". SERVICE BULLETIN NO. 910A MODELS AFFECTED: PA-18/18-A Series Super Cub NOTE: Includes All Serial No. L-21A, L-21B, & L-18, Seaplane, Agricultural, and Military Versions PA-19 Super Cub PART II PAGE 3 OF 5 SERIAL NUMBERS AFFECTED: 18-1 through 18-8309025, 1809001 through 1809032, 1809034 through 1809040 19-1, 19-2 and 19-3 COMPLIANCE TIME: To coincide with the next regularly scheduled inspection event or at next replacement of the wing 11ft strut, but not to exceed twenty-four (24) months from the initial inspection as called for in Part I of this Service Bulletin. PURPOSE: Part II of this Service Bulletin announces the availability of new sealed wing lift struts which, when installed, will relieve inspection requirements of Part I of this Service Bulletin INSTRUCTIONS: 1. Remove old wing lift strut. 2. Prepare, prime and paint new sealed wing lift struts to match aircraft before assembly. 3. Inspect clamps, fairleads and jury struts for condition and replace as necessary. All attaching hardware should be replaced.