{"id":"F2006B09657","name":"AD/F100/55 Amdt 1 - Main Landing Gear Main Fitting - 2","slug":"ad-f100-55-amdt-1-main-landing-gear-main-fitting-2","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115778,"registerId":"commonwealth-F2006B09657-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"“Application of Brakes During Backward M","sectionType":"part","heading":"“Application of Brakes During Backward Movement is Prohibited”","content":"# “Application of Brakes During Backward Movement is Prohibited”\n\n    3. Inspect the MLG Main Fittings in accordance with the Accomplishment Instructions of Messier-Dowty (SB) F100-32-104, dated 22 August 2002, or later UK CAA approved revision.\n\n    4. Whenever a hard or overweight landing is reported and subsequently confirmed by inspection in accordance with the Aircraft Maintenance Manual Chapter 05- 51-01, Table A, inspect the MLG Main Fittings in accordance with the Accomplishment Instructions of Messier-Dowty SB F100-32-104 Revision 2, dated 30 October 2003, or later UK CAA approved revision.\n\n    5. After each occasion when braking has been applied during aircraft backward movement in push-back or power-back operation, inspect the MLG Main Fittings in accordance with the Accomplishment Instructions of Messier-Dowty SB F100- 32-104 Revision 2, or later UK CAA approved revision.\n\n    6. When cracks are found, determine whether and for how many, flights may be continued before repair or replacement; in accordance with the crack size and location thresholds as listed in Fokker Services SB F100-32-137 Revision 2, dated 9 February 2004, or later CAA-NL approved revision.\n\n    7. Irrespective of the results, report all inspection findings to Fokker Services.\n\nNote: CAA-NL AD 2002-115/2 refers.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The supplied text prescribes specific inspection triggers, assessment rules for discovered cracks, and a reporting obligation. It references an earlier CAA-NL AD but does not itself state an expansion or narrowing of regulated items beyond those inspection and reporting requirements set out in the instrument."},"complexity_factors":["Multiple conditional triggers for inspection (routine SB inspection; hard/overweight landing; braking during backward movement) increasing operational monitoring requirements (paras 3–5).","Cross-references to multiple service bulletins and later regulator-approved revisions (Messier-Dowty SB F100-32-104; Fokker SB F100-32-137; UK CAA / CAA-NL approvals) create version-control and approval-compliance burdens (paras 3–6).","Requirement to assess allowable continued flights based on crack size/location thresholds requires specialised assessment and recordkeeping by operators or maintenance providers (para 6).","Mandatory reporting of all inspection findings to Fokker Services imposes an information-flow obligation regardless of inspection outcome (para 7).","Compliance timing and criteria depend on event detection and confirmation processes (hard/overweight landing must be reported and confirmed per AMM), creating operational coordination obligations (para 4)."],"plain_english_summary":"This Directive requires operators of affected F100 aircraft to inspect the main landing gear (MLG) main fittings using specified Messier-Dowty and Fokker service bulletins after certain triggers: routine inspection per the SB, after a confirmed hard or overweight landing, and after any occasion when brakes were applied during backward movement (push-back or power-back). If cracks are found, operators must use Fokker Services thresholds to decide how many further flights are permitted before repair or replacement, and must report all findings to Fokker Services."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This appears to be a focused, targeted airworthiness directive addressing a specific structural vulnerability in Fokker 100 main landing gear. The scope remains tightly constrained to inspection and reporting requirements for this specific safety issue. The multiple inspection triggers and crack-assessment procedures represent necessary operational detail rather than scope creep."},"complexity_factors":["Multiple cross-references to external technical documents (Messier-Dowty SB F100-32-104, Fokker Services SB F100-32-137, Aircraft Maintenance Manual Chapter 05-51-01)","Version-specific requirements with different dates (Revision 2 vs original, different dates for different triggering events)","Conditional logic with four distinct inspection triggers (routine, hard landing, overweight landing, brake application during backward movement)","Nested decision-making when cracks are found (determining flight continuation based on crack size/location thresholds)","Dual regulatory approval references (UK CAA and CAA-NL — the Dutch aviation authority)","Specific aircraft type limitation (Fokker 100 with Messier-Dowty landing gear)"],"plain_english_summary":"This AD mandates inspections of the Messier‑Dowty main landing‑gear main fittings on affected Fokker 100s, requiring operators and maintenance crews to check for cracks, report findings to Fokker Services, and assess remaining safe flight limits if damage is found. \n\nIt bars using brakes while the aircraft is moving backward and requires checks after hard or overweight landings and whenever brakes have been applied in reverse—addressing the risk of fitting damage that could lead to structural failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f100-55-amdt-1-main-landing-gear-main-fitting-2","history":"/api/acts/ad-f100-55-amdt-1-main-landing-gear-main-fitting-2/history","analysis":"/api/acts/ad-f100-55-amdt-1-main-landing-gear-main-fitting-2/analysis","conflicts":"/api/acts/ad-f100-55-amdt-1-main-landing-gear-main-fitting-2/conflicts","importantCases":"/api/acts/ad-f100-55-amdt-1-main-landing-gear-main-fitting-2/important-cases","documents":"/api/acts/ad-f100-55-amdt-1-main-landing-gear-main-fitting-2/documents"}}