{"id":"F2006B08890","name":"AD/DH 60/3 Amdt 1 - Datum Bolts","slug":"ad-dh-60-3-amdt-1-datum-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52382,"registerId":"commonwealth-F2006B08890-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH 60/3 Amdt 1 - Datum Bolts","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)  \nDe Havilland DH 60 (Moth) Series Aeroplanes\n\nAD/DH 60/3\n\nAmdt 1\n\n  \nDatum Bolts 10/98\n\nApplicability: Model DH60 (except 60G and 60M), Moth aircraft.\n\nRequirement: Action in accordance with British Aerospace Technical News Sheet CT (Moth) No.\n\n28 Issue 2.\n\nNote: UK CAA AD 002-10-97 refers.\n\nCompliance: Unless already accomplished, within 25 hours time in service after 10 September 1998, or before 10 December 1998, whichever occurs first.\n\nThis amendment becomes effective on 10 September 1998.\n\nBackground: Moth aircraft have special bolts installed at certain fuselage joints which serve as “datum pins” when rigging the aircraft longitudinally. Although these bolts are similar in appearance, their material specifications differ. This Directive requires an inspection of the bolts installed at joint “E” (on some models) to determine the material specification.\n\nAmendment 1 is issued in response to Issue 2 of the Requirement document which introduces an additional one-time inspection and replacement, where necessary, of the fuselage Joint ‘E’ bolts on the opposite side of the aircraft to the datum bolts, and to allow the use of A25 bolts in lieu of obsolete specification AGS. 749 bolts.\n\nThe original issue of this airworthiness directive became effective on 12 November 1997.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment stays tightly focused on its original purpose: ensuring correct datum bolts in DH 60 Moth aircraft. The changes from the original 1997 directive are minor technical adjustments — adding an inspection on the opposite fuselage side and updating permitted replacement bolt specifications. No scope creep."},"complexity_factors":["Single specific aircraft type (De Havilland DH 60 series)","Only 2 models excluded from applicability (60G, 60M)","One primary action required (inspection per British Aerospace technical document)","Simple compliance deadline (25 hours or fixed date, whichever first)","No nested exceptions or conditional logic","Cross-reference to only one external document (UK CAA AD 002-10-97)","Background explanation provided in plain language"],"plain_english_summary":"This safety order targets De Havilland DH.60 Moth/Major/Minor biplanes, requiring inspection of visually identical but materially different bolts at a critical fuselage joint and replacement if incorrect. It permits modern A25 bolts as substitutes for obsolete AGS.749 parts.\n\nAffecting a few dozen vintage aircraft in museums, collections, or scenic service, the amendment adds an inspection on the opposite fuselage side and sets a short compliance window (25 flight hours or December 1998), to protect structural integrity in flight."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 expands the original directive by adding a one‑time inspection and replacement, if necessary, of the fuselage Joint ‘E’ bolts on the side opposite the datum bolts, and by allowing the use of A25 bolts in lieu of the obsolete AGS.749 specification. The original AD became effective 12 November 1997; this amendment became effective 10 September 1998."},"complexity_factors":["Narrow applicability to specific aircraft models (DH60 series, excluding 60G and 60M)","Short, mandatory compliance window (25 hours TIS or specific calendar date)","Reference to an external technical document (British Aerospace Technical News Sheet CT (Moth) No.28 Issue 2) for the required actions","Amendment introduces an additional one‑time inspection on the side opposite the datum bolts","Permits substitution of bolt specification (A25 allowed instead of obsolete AGS.749), creating a technical parts-spec decision point","Cross-reference to UK CAA AD for related information"],"plain_english_summary":"Requires owners/operators of De Havilland DH60 Moth series (except 60G and 60M) to inspect the fuselage joint “E” datum bolts and replace any that do not meet the specified material standard, following British Aerospace Technical News Sheet CT (Moth) No. 28 Issue 2. Compliance is required within 25 hours TIS after 10 September 1998 or by 10 December 1998. The Civil Aviation Safety Authority issued the directive; aircraft owners bear the cost and must follow the specified bolt-spec substitutions (A25 permitted in place of obsolete AGS.749)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh-60-3-amdt-1-datum-bolts","history":"/api/acts/ad-dh-60-3-amdt-1-datum-bolts/history","analysis":"/api/acts/ad-dh-60-3-amdt-1-datum-bolts/analysis","conflicts":"/api/acts/ad-dh-60-3-amdt-1-datum-bolts/conflicts","importantCases":"/api/acts/ad-dh-60-3-amdt-1-datum-bolts/important-cases","documents":"/api/acts/ad-dh-60-3-amdt-1-datum-bolts/documents"}}