# Piper Service Bulletin 547: No revision named - Rights: © Piper. Filed by the FAA in regulations.gov docket FAA-2020-1006; AD 2021-25-11 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Piper Service Bulletin 547](https://openairdocs.org/service-documents/piper/sb-547.md) - Title as filed: Piper Service Bulletin No. 547 - Pages: 3 - PDF: https://openairdocs.org/files/sha256/98/ac/98acbea373641e93699323025146cfbe799d1130a9751818f8ab1303cab6c381 - Page: https://openairdocs.org/service-documents/piper/sb-547/file/98acbea37364 ## Text This text is OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 (OCR) SERVICE NO. 547 PIPER BULLETIN Piper Aircraft Corporation Lock Haven, Pennsylvania, U.S.A. "Modification DOA EA-1 Approved" March 1, 1977 M Subject: Inspection of Stabilator Tip Rib Models Affected: Serial Numbers Affected: PA-23-250 (6 Place) Aztec "F" 27-7654001 to 27-7754054 Inclusive (see NOTE, below) NOTE: Above referenced aircraft serial numbers 27-7654001 to 27-7754041 Inclusive are affected only if either or both stabilators have been replaced with any of the following listed stabilators (issued from factory service stock): Stabilator Assy. - Stabilator Assy. - Part No. Left Right Serial Number* 15658 - 26 -27 27-0272 -27 27-0275 - 26 27-0281 -26 -27 27-0282 - 26 - 27 27-0283 - 26 - 27 27-0284 - 26 - 27 27-0285 - 27 27-0286 -26 -27 27-0291 - 26 27-0292 - 27 27-0293 - 26 27-0298 -27 27-0299 - 26 27-0301 - 27 27-0302 - 26 27-0304 -27 27-0305 * The same stabilator serial numbers applies to both -26 (left) and -27 (right) stabilators fabricated as "matched pairs"; units fabri- cated individually bear an individual serial number. over ### Page 2 (OCR) Service Bulletin No. 547 (Continued) Page 2 Compliance Time: Within the next fifty (50) hours of operation Purpose: Resulting from the inspection specified in Piper Service Bulletin No. 540 dated January 4, 1977, it was found that certain stabilator tip rib rivets and/or the stabilator tip tube and weight assembly attachment screw may be missing. Although no failures have been reported as a result of this condition, inattention to this matter could lead to cracking in the stabilator tip rib area. This Service Bulletin provides instructions to inspect the stabilator tip rib area to determine that the correct attachment hardware is installed and specifies proper hardware to be installed, if necessary (refer to attached sketch/instruction sheet for an illustrated view of this area). Instructions: Refer to attached sketch/instruction sheet for inspection instructions and hardware installation details. Material Required: Reference attached sketch/instruction sheet. Availability of Parts: Your Piper Field Service Facility. Effectivity Date: This Service Bulletin is effective upon receipt. Summary: Please contact your Piper Field Service Facility to make arrangements for compliance with this Service Release in accordance with the provisions of Compliance Time, above. Reimbursement for modification material and labor (one hour) allowance credit-- if required--is available through your Piper Field Service Facility in accordance with their respective material/labor allowance credit application procedure. ### Page 3 (OCR) EWD 1.33 • 2.62- 1.30→ 1.00→.75→ • 1. 66 Existing Rivets . 28 68 18 Rivet NAS1738B4-3 (4 Req. ) Screw (MS35207-268) Rivet NAS1738B4-1 (7 Req. ) Tube & Weight Assembly END VIEW OF STABILATOR TIP RIB (Left Shown - Right Opposite) INSTRUCTIONS 1. Remove tip assembly from left and right stabilators. 2. Inspect forward end of stabilator ribs to determine if five rivets are installed aft of the tube & weight assembly attachment plate, two rivets installed forward of the attachment plate and a screw installed thru the square tube welded to the attachment plate. 3. If screw and rivets are present on both stabilators, reinstall tip assemblies and make proper logbook entry of Service Bulletin 547 inspection compliance. 4. If screw and rivets are missing from either stabilator, install new hardware as follows: a. Install MS35207-268 screw (P/N 411 537) thru the square tube and into the anchor nut as shown. b. Locate and drill eleven. 144 holes as shown above. c. Install four NAS1738B4-3 blind rivets (P/N 522 883) at the attachment plate and seven NAS1738B4-1 blind rivets (P/N 522 881) aft and forward of the attachment plate. d. Reinstall tip assembly and make proper logbook entry of stabilator rivet and screw installation per Service Bulletin 547. S.B. #547 --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.