{"id":"F2006B06421","name":"AD/R22/16 Amdt 4 - Lower Actuator Bearing","slug":"ad-r22-16-amdt-4-lower-actuator-bearing","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47790,"registerId":"commonwealth-F2006B06421-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/R22/16 Amdt 4 - Lower Actuator Bearing","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)  \nRobinson R22 Series Helicopters\n\nAD/R22/16\n\nAmdt 4\n\n  \nLower Actuator Bearing 13/94\n\nApplicability: All series R22 helicopters.\n\nRequirement: Inspect lower bearing assembly P/N A007-3 for fitment of roller bearing assembly P/N A181-4. If the bearing P/N is unknown or if roller bearing assembly P/N A181-4 has not been fitted, action in accordance with Robinson SB 63.\n\nCompliance: Unless previously carried out, within 25 hours time in service from 8 December 1994 or by 31 January 1995, whichever occurs first. Thereafter, reinspect at each maintenance release issue.\n\nBackground: Due to the low in-service life of the fan shaft ball bearing the manufacturer has previously introduced a replacement roller bearing. Failure of a fan shaft bearing can resulted in total loss of engine power to the main rotor. This amendment mandates fitment of the roller bearing and a repetitive check to confirm the roller bearing installation after failure of a commercial ball bearing caused a helicopter accident.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2171},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"This amendment expanded the original directive's scope by mandating the specific fitment of the roller bearing assembly (rather than merely recommending it) and introducing a repetitive inspection requirement following an accident investigation."},"complexity_factors":["References external technical document (Robinson SB 63) without reproducing its content","Dual compliance triggers requiring calculation (25 flight hours versus specific calendar date)","Technical part number specificity (P/N A007-3, P/N A181-4)","Ongoing repetitive inspection obligation tied to maintenance release cycle"],"plain_english_summary":"This Airworthiness Directive requires all Robinson R22 owners/operators to inspect the lower actuator bearing and ensure the original ball bearing has been replaced with the safer roller bearing to prevent catastrophic in‑flight engine loss. If the upgraded bearing isn’t present or identification isn’t possible, follow Robinson Service Bulletin 63 to correct it. The initial inspection was required within 25 flight hours of 8 Dec 1994 (or by 31 Jan 1995) and must be repeated at each maintenance‑release thereafter."}},"importantCases":[],"_links":{"self":"/api/acts/ad-r22-16-amdt-4-lower-actuator-bearing","history":"/api/acts/ad-r22-16-amdt-4-lower-actuator-bearing/history","analysis":"/api/acts/ad-r22-16-amdt-4-lower-actuator-bearing/analysis","conflicts":"/api/acts/ad-r22-16-amdt-4-lower-actuator-bearing/conflicts","importantCases":"/api/acts/ad-r22-16-amdt-4-lower-actuator-bearing/important-cases","documents":"/api/acts/ad-r22-16-amdt-4-lower-actuator-bearing/documents"}}