{"id":"F2006B05704","name":"AD/PA-31/117 - Elevator Spar, False Spar and Butt Rib","slug":"ad-pa-31-117-elevator-spar-false-spar-and-butt-rib","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":135503,"registerId":"commonwealth-F2006B05704-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-31/117 - Elevator Spar, False Spar and Butt Rib","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Piper PA-31 Series Aeroplanes\n\n \n\nAD/PA-31/117 Elevator Spar, False Spar and Butt Rib 11/90\n\nApplicability: PA-31P, 31T, 31T1, 31T2 as indicated in the Requirement document.\n\n \n\nRequirement: Inspect in accordance with Part I of Piper Service Bulletin No 897A dated 3 January 1990.\n\n \n\nNote: Compliance with Part II of the above Service Bulletin constitutes terminating action for the purposes of this AD.\n\n \n\nCompliance: Within 100 hours time in service after 1 November 1990, and thereafter at intervals not to exceed 500 hours time in service.\n\n \n\nBackground:  It has been determined that cracks may occur in the false spar channels, the elevator butt ribs and the elevator spar at the butt rib attachment. Uncorrected, such a condition may lead to impairment of elevator control.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":800},"content_quality":"ok","complexity_score":3,"rejection_reason":"","scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope - addressing a specific structural cracking issue in specific Piper aircraft models. It has not expanded beyond the original safety concern regarding elevator component integrity."},"complexity_factors":["Technical terminology specific to aviation maintenance (spar, butt rib, time in service)","Reference to external technical document (Piper Service Bulletin 897A) without reproducing its contents","Conditional compliance pathway (Part II constitutes terminating action)","Specific applicability limited to four aircraft sub-models"],"plain_english_summary":"**What this does:** This Airworthiness Directive (AD) mandates safety inspections on specific Piper aircraft to prevent elevator control failure.\n\n**Who it affects:** Owners and operators of Piper PA-31P, 31T, 31T1, and 31T2 aircraft.\n\n**What must be done:**\n- **Inspect** the elevator spar, false spar channels, and butt ribs for cracks using **Piper Service Bulletin No 897A Part I** (a manufacturer-issued technical instruction)\n- **First inspection:** Within 100 flight hours after 1 November 1990\n- **Repeat inspections:** Every 500 flight hours thereafter\n- **Permanent fix:** Following Part II of the same Service Bulletin counts as \"terminating action\" (meaning you can stop the repetitive inspections once this modification is done)\n\n**Why it matters:** Cracks were discovered in these structural components that attach the elevator (the part that makes the plane pitch up and down). If left unchecked, these cracks could break, causing loss of elevator control and potentially a crash."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-31-117-elevator-spar-false-spar-and-butt-rib","history":"/api/acts/ad-pa-31-117-elevator-spar-false-spar-and-butt-rib/history","analysis":"/api/acts/ad-pa-31-117-elevator-spar-false-spar-and-butt-rib/analysis","conflicts":"/api/acts/ad-pa-31-117-elevator-spar-false-spar-and-butt-rib/conflicts","importantCases":"/api/acts/ad-pa-31-117-elevator-spar-false-spar-and-butt-rib/important-cases","documents":"/api/acts/ad-pa-31-117-elevator-spar-false-spar-and-butt-rib/documents"}}