{"id":"F2011L00281","name":"Part 145 Manual of Standards (MOS)","slug":"part-145-manual-of-standards-mos","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":85526,"registerId":"commonwealth-F2011L00281-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Category A licence tasks","sectionType":"division","heading":"Category A licence tasks","content":"### Category A licence tasks\n\nMaintenance activities — authority in subcategory A1, A2, A3 or A4\n\nThis Appendix outlines the scope of authorisations that an AMO may issue to employees qualified under Part 66 of CASR 1998 as Category A, to perform maintenance certification and issue certificates of release to service.\n\n1 Minor scheduled line maintenance, including a scheduled inspection or check, up to and including a weekly check:\n\n(a) specified in the registered operator’s approved aircraft maintenance program; or\n\n(b) if not specified in the registered operator’s approved aircraft maintenance program, which CASA considers is equivalent to a weekly check and lists in Part 66 guidance material.\n\n2 Minor maintenance, including a pre-flight, transit or overnight check, ground handling, APU running and minimum equipment list (MEL) implementation as allowed by paragraph 3 (p).\n\n3 Minor scheduled line maintenance or simple defect rectification tasks:\n\n(a) replacement of wheel assemblies; and\n\n(b) replacement of wheel brake units; and\n\n(c) replacement of emergency equipment; and\n\n(d) replacement of ovens, boilers and beverage makers; and\n\n(e) replacement of internal and external lights, filaments and flash tubes; and\n\n(f) replacement of windscreen wiper blades; and\n\n(g) replacement of passenger or cabin crew seats, seat belts and harnesses; and\n\n(h) closing of cowlings and refitment of quick access inspection panels; and\n\n(i) replacement of toilet system components, other than gate valves; and\n\n(j) simple repair and replacement of internal compartment doors and placards, other than doors forming part of a pressure structure; and\n\n(k) simple repair and replacement of overhead storage compartment doors and cabin furnishing items; and\n\n(l) replacement of static wicks; and\n\n(m) replacement of aircraft main and APU batteries; and\n\n(n) replacement of in-flight entertainment system components, other than public address; and\n\n(o) routine lubrication and replenishment of system fluids and gases; and\n\n(p) implementation of a registered operator’s MEL, including deactivation of subsystems and aircraft components as permitted by the MEL, if the MEL application is one that CASA approves as a simple task; and\n\n(q) replacement of any other component for an aircraft type if the task is one that CASA approves as a simple task; and\n\n(r) For a helicopter only:\n\n(i) removal or installation of the following:\n\n(A) simple medical equipment carried inside a helicopter used for emergency medical services;\n\n(B) external cargo provisions (for example, external hook, mirrors), excluding the hoist;\n\n(C) quick release external cameras and search lights;\n\n(D) emergency float bags, excluding the bottles;\n\n(E) external doors fitted with quick release attachments;\n\n(F) snow pads, skid wear shoes or slump protection pads; and\n\n(ii) removal, inspection and re-installation of chip detectors, including on inspection “go” or “no go” decision on chip or fuzz or swarf; and\n\n(iii) folding or deploying rotor blades if:\n\n(A) handling instructions permit folding for storage; and\n\n(B) ground support equipment is available; and\n\n(iv) visual inspection or tap test of rotor blades; and\n\n(v) minor repairs, including stop drilling and bonding, to acrylic or Perspex windscreens.","sortOrder":0},{"sectionNumber":"Conditions for the use of employees not ","sectionType":"division","heading":"Conditions for the use of employees not qualified to Part 66 of CASR 1998 in accordance with paragraph 145.A.30 (k)","content":"### Conditions for the use of employees not qualified to Part 66 of CASR 1998 in accordance with paragraph 145.A.30 (k)\n\nCertifying employees complying with the following conditions will meet the requirements of paragraph 145.A.30 (k):\n\n(a) the individual must hold an appropriate licence issued by an NAA under the country’s national regulations that is an ICAO Annex 1 aircraft maintenance licence;\n\n(b) the scope of work of the individual must not exceed the scope of work defined by the national licence;\n\n(c) the individual must have received training on human factors and airworthiness regulations equivalent to that detailed in Part 66 of CASR 1998;\n\n(d) the individual must demonstrate 5 years’ maintenance experience for a line maintenance certifying employee and 8 years for a base maintenance certifying employee. However, an individual whose authorised tasks do not exceed those of a Part 66 Category A certifying employee, need only demonstrate 3 years maintenance experience;\n\n(e) maintenance certifying employees must receive type training at a level corresponding to Appendix III of the Part 66 MOS, for every aircraft on which he or she is authorised to make certification. However, those individuals whose authorised tasks do not exceed those of a Part 66 Category A certifying employee may receive task training in lieu of complete type training.\n\nNote to Part 145 Manual of Standards (MOS)\n\n> Note: The Part 145 Manual of Standards (MOS) (in force under the Civil Aviation Safety Regulations 1998) as shown in this compilation comprises Manual of Standards Part 145 Instrument 2011 amended as indicated in the Tables below.\n\n> Note: > Note: Table of Manual of Standards and Amendments\n\n| Year andnumber | Date of registration on FRLI | Date ofcommencement | Application, saving ortransitional provisions |\n| ---------------------------- | ------------------------------------------------------------------------------------- | ------------------- | --------------------------------------------- |\n| MOS 145 2011 | 18 February 2011 (F2011L00281) | 27 June 2011 | |\n| MOS 145 2011 Amendment No. 1 | 22 June 2011 (F2011L01192) | 27 June 2011 | — |\n| MOS 145 2012 Amendment No. 1 | 5 April 2012 (F2012L00794) | 6 April 2012 | — |\n| MOS 145 2012 Amendment No. 2 | 25 June 2012 (F2012L01326) | 26 June 2012 | — |\n| MOS 145 2014 Amendment No. 1 | 2 October 2014 (F2014L01316)Note: disallowed by the Senate on 18 March 2015 at 17:57. | 3 October 2014 | — |\n\n```html\n

Table of Amendments

ad. = added or inserted am. = amended rep. = repealed rs. = repealed and substituted

Provision affected

How affected

s. 1

rs. MOS 145 2011 No. 1

s. 2

am. MOS 145 2011 No. 1

s. 3

rep. MOS 145 2011 No. 1

Schedule heading

rep. MOS 145 2011 No. 1

MOS title

rep. MOS 145 2011 No. 1

s. 145.A.01

am. MOS 145 2014 No. 1 (disallowed)

s. 145.A.05

am. MOS 145 2011 No. 1

s. 145.A.12

am. MOS 145 2011 No. 1, MOS 145 2012 No. 2, MOS 145 2014 No. 1 (disallowed)

s. 145.A.25

am. MOS 145 2014 No. 1 (disallowed)

s. 145.A.30

am. MOS 145 2011 No. 1, MOS 145 2012 No. 1, MOS 145 2012 No. 2, MOS 145 2014 No. 1 (disallowed)

s. 145.A.35

am. MOS 145 2011 No. 1, MOS 145 2012 No. 2, MOS 145 2014 No. 1 (disallowed)

s. 145.A.37

am. MOS 145 2011 No. 1, MOS 145 2012 No. 1, MOS 145 2014 No. 1 (disallowed)

s. 145.A.40

am. MOS 145 2011 No. 1, MOS 145 2012 No. 1

s. 145.A.42

am. MOS 145 2014 No. 1 (disallowed)

s. 145.A.45

am. MOS 145 2011 No. 1, MOS 145 2014 No. 1 (disallowed)

s. 145.A.55

am. MOS 145 2011 No. 1

s. 145.A.60

am. MOS 145 2011 No. 1, MOS 145 2014 No. 1 (disallowed)

s. 145.A.65

am. MOS 145 2014 No. 1 (disallowed)

s. 145.A.70

am. MOS 145 2012 No. 2, MOS 145 2014 No. 1 (disallowed)

s. 145.A.75, heading

rs. MOS 145 2014 No. 1 (disallowed)

s. 145.A.75

rs. MOS 145 2014 No. 1 (disallowed)

Appendix I

am. MOS 145 2011 No. 1, MOS 145 2012 No. 1, MOS 145 2014 No. 1 (disallowed)

Appendix II

am. MOS 145 2011 No. 1, MOS 145 2012 No. 2, MOS 145 2014 No. 1 (disallowed)

Appendix III

am. MOS 145 2011 No. 1, MOS 145 2014 No. 1 (disallowed)

Appendix IV

ad. MOS 145 2014 No. 1 (disallowed)

\n```","sortOrder":1}],"analysis":{"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"Compared with a narrow original purpose of specifying Category A certificating tasks for Part 66 licence holders, this version broadens scope in two concrete ways: (1) it sets out detailed conditions that permit AMOs to use non‑Part 66 certifying employees who hold foreign (ICAO Annex 1) licences, subject to training and experience tests (paragraph 145.A.30(k) and conditions (a)–(e)); and (2) it explicitly brings certain MEL implementation actions and a wider list of component replacements (including helicopter‑specific items) into the pool of tasks that Category A employees may certify, but only where CASA or the operator’s MEL treats those as \"simple\" tasks (see item 3(p) and 3(q), and item 1(b) referring to CASA guidance). Those changes increase operational flexibility for AMOs and operators but also shift authority to CASA to approve equivalence and \"simple task\" status, materially expanding administrative discretion compared with a text that only listed Category A tasks for domestic Part 66 licence holders."},"complexity_factors":["Numerous specific task subitems (items 1–3 with subparagraphs a–r, including nested helicopter subpoints r(i)–r(iii)(A)–(F)).","Cross‑references to other instruments: Part 66 of CASR 1998, Appendix III of the Part 66 MOS, and registered operator MELs.","Conditional approvals and discretionary gates (CASA must approve what counts as a \"simple task\" and provides guidance material on equivalence).","Exceptions and alternative routes (experience reduced to 3 years when authorised tasks do not exceed Category A; task training permitted in lieu of full type training for such cases).","Dependence on external guidance material (CASA lists equivalence for weekly check; subject to change and interpretive variability).","Amendment history with additions, repeals and at least one set of disallowed amendments recorded in the Table of Amendments (creates potential uncertainty about which versions apply where)."],"plain_english_summary":"**What this instrument does (mechanically)\n\n- Sets out the tasks a Category A maintenance certifying employee (a person qualified under Part 66 of the Civil Aviation Safety Regulations 1998 as Category A) may be authorised by an Approved Maintenance Organisation (AMO) to perform and certify.\n- Lists three broad task groups: (1) minor scheduled line maintenance up to a weekly check; (2) routine minor maintenance such as pre‑flight, transit or overnight checks, ground handling, APU running and implementation of certain Minimum Equipment List (MEL) actions; and (3) a long list of simple defect rectification and component replacement tasks (items (a)–(q)), plus a set of helicopter‑specific items (item (r)).\n- Allows an AMO to authorise Category A certifying employees to implement parts of a registered operator’s MEL, but only where the MEL application is one that CASA approves as a \"simple task\" (see paragraph 3(p)).\n- Prescribes conditions under which an AMO may use employees who are not holders of a Part 66 licence but do hold an equivalent ICAO Annex 1 licence issued by another national aviation authority (NAA). Those conditions cover: scope‑of‑licence limitation, equivalent human factors and airworthiness training, specified years of maintenance experience (5 years line / 8 years base; or 3 years where authorised tasks do not exceed Category A), and required type or task training (see paragraph 145.A.30(k) and the conditions section).\n\nWho this affects\n\n- Approved Maintenance Organisations (AMOs): they decide which employees to authorise and must ensure authorised persons meet the listed conditions.\n- Category A certifying employees (Part 66 Category A licence holders): the document defines exactly what work and certification they may be authorised to do.\n- Operators that rely on MEL relief or on non‑Australian licence holders: CASA must approve simple MEL tasks; foreign‑licenced certifiers must meet the stated equivalence and experience conditions.\n- CASA (the regulator): retains approval and discretion functions (e.g. approving MEL tasks as \"simple\" and approving equivalence in guidance material).\n\nWhy it matters (purpose claim and mechanical test)\n\n- The instrument’s stated purpose is to define the scope of Category A authorisations and set conditions for using non‑Part 66 certifying employees. Mechanically it narrows or clarifies which routine and minor tasks may be certified by lower‑level maintenance staff and creates a pathway to use suitably qualified foreign licence holders under specified safeguards (paragraph 145.A.30(k)).\n\nCosts, incentives and trade‑offs (mechanisms, not judgments)\n\n- Who pays: AMOs and operators bear direct costs for training, type/task training records, supervision and administrative compliance. They may also reallocate labour costs if lower‑paid Category A staff replace higher‑graded certifiers for enumerated tasks.\n- Who decides: AMOs authorise employees; CASA must approve which MEL actions count as \"simple\" and provides guidance on what counts as an equivalent weekly check. CASA therefore holds gatekeeping discretion that affects how wide an AMO can make its internal authorisations (see paragraph 3(p) and the reference to CASA guidance material).\n- Behavioural effects: AMOs can lawfully assign routine line tasks to Category A certifiers (reducing need for higher‑category certifiers for those tasks). Operators may also import certifying capacity by using foreign ICAO Annex 1 licence holders if they meet the equivalence and experience conditions.\n- Incentives and trade‑offs: The rules lower the formal qualification threshold for many routine tasks (potentially reducing labour cost for operators), while imposing supervisory, training and documentation obligations on AMOs. CASA’s approval role creates a single regulator point that can limit or expand what is done under an AMO’s authorisation.\n- Substitution effects: Tasks listed (replacement of wheels/brakes, batteries, lights, seats, in‑flight entertainment components, static wicks, simple lubrication, certain helicopter items, etc.) are explicitly moved into the pool of work Category A staff may certify, which may substitute away from higher‑qualified maintenance staff for those tasks (items 3(a)–(q) and 3(r)).\n- Concentrated benefits and diffuse costs: Benefits (lower labour/outsourcing costs, operational flexibility) concentrate with AMOs and operators; oversight, recordkeeping and potential safety monitoring costs are dispersed across the regulator and, indirectly, the travelling public. Whether the net effect changes risk profiles depends on implementation (training quality, supervision, CASA approvals).\n- Implementation and compliance risk: The instrument depends on external cross‑references (Part 66 definitions, Appendix III for type training, CASA guidance material for equivalence). That creates execution risk where equivalence, what constitutes a \"simple task\", or sufficiency of type/task training are contested or inconsistently applied.\n\nKey textual hooks (where to look in the text)\n\n- Category A task list: items 1–3 and subparagraphs (a)–(r) set the authorised tasks (including 3(p)–MEL implementation and 3(q)–CASA‑approved simple tasks).\n- Conditions for non‑Part 66 certifying employees: paragraph 145.A.30(k) and the following conditions (a)–(e), including the experience and training exemptions and the reference to Appendix III of the Part 66 MOS.\n- Regulator discretion points: CASA approvals for simple MEL tasks and CASA guidance material on equivalence (noted in item 1(b) and 3(p)).\n\nPractical compliance checklist for an AMO (mechanical steps)\n\n- Verify which Category A tasks you intend to authorise against the list (items 1–3(a)–(r)).\n- If relying on non‑Part 66 foreign licence holders, confirm the licence is ICAO Annex 1 compliant and check the employee meets experience and training conditions in paragraph 145.A.30(k).\n- Document and retain evidence of type or task training per Appendix III (or task training where authorised), human factors and airworthiness regulations equivalence, and supervisory arrangements. \n- Seek CASA confirmation where an MEL action or a component replacement is to be treated as a CASA‑approved \"simple task.\""},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":6,"scope_assessment":{"changed":false,"description":"This excerpt appears to be a technical appendix and conditions section that serves its original purpose of defining certification boundaries for Category A licence holders and alternative qualification pathways. There is no evidence of scope creep beyond the original aviation maintenance safety framework. The amendment history shows technical updates rather than expansion into new policy areas."},"complexity_factors":["Heavy cross-referencing to external documents: Part 66 of CASR 1998, ICAO Annex 1, Appendix III of Part 66 MOS, and operator-specific maintenance programs","Nested conditional logic: Multiple 'if' conditions throughout (e.g., paragraph 3(p) on MEL implementation requires CASA approval as a 'simple task'; paragraph 3(q) requires CASA approval for any other component replacement)","Aircraft-type specificity: Different rules for helicopters versus fixed-wing aircraft, with helicopter-specific sub-paragraphs containing their own nested lists","Alternative compliance pathways: The non-Part 66 section contains layered exceptions (e.g., 5 years experience normally, but 8 years for base maintenance, but only 3 years if tasks limited to Category A level)","Defined terms used but not defined in this excerpt: 'AMO', 'CASA', 'MEL', 'APU', 'line maintenance', 'base maintenance', 'type training', 'task training', 'ICAO Annex 1', 'NAA'","Structural fragmentation: The excerpt shows signs of compilation with amendment tables and HTML table markup indicating this is a consolidated version with historical amendments tracked"],"plain_english_summary":"This instrument defines the limited maintenance and sign‑off powers of Part 66 Category A licence holders — routine checks, simple replacements and basic servicing — and the conditions under which AMOs may accept non‑Australian (ICAO Annex 1) maintenance licences. It sets training, experience and task‑/type‑specific requirements for overseas workers and restricts Category A work to lower‑risk tasks. The rules matter for safety, regulatory compliance, insurance and workforce flexibility."}},"importantCases":[],"_links":{"self":"/api/acts/part-145-manual-of-standards-mos","history":"/api/acts/part-145-manual-of-standards-mos/history","analysis":"/api/acts/part-145-manual-of-standards-mos/analysis","conflicts":"/api/acts/part-145-manual-of-standards-mos/conflicts","importantCases":"/api/acts/part-145-manual-of-standards-mos/important-cases","documents":"/api/acts/part-145-manual-of-standards-mos/documents"}}