{"id":"F2006B01977","name":"AD/A320/88 - Wing Front Spar Vertical Stringers","slug":"ad-a320-88-wing-front-spar-vertical-stringers","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41199,"registerId":"commonwealth-F2006B01977-current","compilationNumber":null,"startDate":"2026-04-01","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A320/88 - Wing Front Spar Vertical Stringers","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/88 Wing Front Spar Vertical Stringers 2/98\n\nApplicability: All A320 models without Modification 21290 or Service Bulletin A320-57-1017 incorporated.\n\nRequirement: 1. Perform an eddy current inspection at the top end of the front spar vertical stringers at frame 36 in accordance with the instructions given in Airbus Industrie Service Bulletin A320-57-1016.\n\n    2. If cracks are detected, dependent upon SB A320-57-1016 Accomplishment Instructions synoptic chart, repeat the inspection defined in Requirement 1 of this Directive, or contact manufacturer.\n\n    3. If no crack is detected, repeat the inspection defined in Requirement 1 of this Directive.\n\nNote: DGAC AD 97-311-105 (B) refers.\n\nCompliance: 1. Before the accumulation of 24,000 flights.\n\n    2. Before next flight or at intervals not to exceed 4,000 flights, as determined by SB A320-57-1017 chart.\n\n    3. At intervals not to exceed 14,000 flights.\n\nThis airworthiness directive becomes effective on 29 January 1998.\n\nBackground: During full scale fatigue tests, bending cracks were found on the front spar vertical stringer at Frame 36. On in-service aircraft, undetected cracks can propagate and form a long crack in the top end of the front spar vertical stringers.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1529},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This appears to be the original issuance of the directive, maintaining a tight focus on the specific wing front spar cracking issue identified during full-scale fatigue testing. The scope targets only the affected aircraft models and the specific structural component where defects were discovered."},"complexity_factors":["Conditional compliance pathways requiring different actions based on inspection findings (cracked vs uncracked scenarios)","References to external technical documents (Airbus Service Bulletins A320-57-1016 and A320-57-1017) without reproducing their contents","Technical aviation terminology (eddy current inspection, front spar vertical stringers, frame 36) requiring specialized engineering knowledge","Tiered recurring inspection intervals (4,000 vs 14,000 flights) dependent on conditional outcomes"],"plain_english_summary":"This mandatory Civil Aviation Safety Authority order requires owners/operators of certain Airbus A319/A320/A321 aircraft (unless they've installed Modification 21290 or Service Bulletin A320‑57‑1017) to perform eddy‑current inspections of a wing front‑spar stringer at frame 36 before 24,000 total flights and at regular intervals. If cracks are found the aircraft must be grounded and either inspected more frequently or repaired per Airbus; if not, repeat inspections at 14,000‑flight intervals. It closes a safety gap from stress‑testing that revealed crack growth risk."}},"importantCases":[],"_links":{"self":"/api/acts/ad-a320-88-wing-front-spar-vertical-stringers","history":"/api/acts/ad-a320-88-wing-front-spar-vertical-stringers/history","analysis":"/api/acts/ad-a320-88-wing-front-spar-vertical-stringers/analysis","conflicts":"/api/acts/ad-a320-88-wing-front-spar-vertical-stringers/conflicts","importantCases":"/api/acts/ad-a320-88-wing-front-spar-vertical-stringers/important-cases","documents":"/api/acts/ad-a320-88-wing-front-spar-vertical-stringers/documents"}}