DASR 4/1994 - Instructions

The instrument organises obligations by three technical axes: radio communications (Part 1), radio navigation and distance measuring (Part 2), and ancillary equipment (Part 3). The primary conceptual design is rule-by-context: identify operation type, route/airspace characteristics and aircraft attributes, then require a specific set or combination of equipment items.

Key categories and the mechanisms they trigger:

• Operation types and contexts: “regular public transport operations”, “charter operations”, “aerial work operations”, “operations in remote areas”, operations “other than” specified items, and “operations outside uncontrolled airspace” or “in controlled airspace” (see cl 1.1 Table; Part 2, cl 2.1(1)-(6)). The instrument repeatedly predicates obligations on whether the flight is operating under I.F.R.
• Communications equipment choices: the instrument sets prescriptive minimums,examples include “1 VHF and 1 HF system; OR 2 VHF systems” for regular public transport (Part 1 Table, Item 1), and single VHF or HF requirements for other categories. Where HF fitment would otherwise be required, an alternative is allowed if the aircraft carries equipment “that enables continuous radio communication with an appropriately-trained representative of the aircraft’s operator” (cl 1.1(3)-(4)). HF systems must also be configured with frequencies “appropriate to the area of operation” and “sufficient to enable continuous communication with Air Traffic Control or Flight Service during the flight including ground operations” (cl 1.1(5)).
• Navigation equipment combinations: the instrument uses “either/or” constructions to allow multiple acceptable configurations. For example, on a VHF omni-directional radio range (VOR)-served route, an RPT aircraft must have either two VOR systems or “a VHF omni-directional radio range system and an automatic direction finding system” and must also have distance measuring equipment (cl 2.1(1)(d)-(e)). When VOR is not available, the acceptable configurations shift toward automatic direction finding systems (ADF) with DME (cl 2.1(2)). Aircraft weight thresholds (more than or less than 5,700 kilograms maximum take-off weight) and whether operations occur in controlled or uncontrolled airspace change the permissible combinations (cl 2.1(3)-(6)).
• Ancillary and conditional requirements: a timepiece accurate to within 30 seconds must be carried by the aircraft operating under I.F.R. unless the pilot in command carries a timepiece accurate to the same standard (cl 3.1). Airborne weather radar is required for two-or-more crew aircraft engaged in RPT or charter, with stated exceptions for certain small or unpressurised types (cl 3.2). Secondary surveillance transponder serviceability and Mode A/C capability are preconditions for starting operations in controlled airspace within radar coverage (cl 3.3(1)), with an express exception for “general aviation aerodrome procedures control zones and associated lanes of entry” (cl 3.3(2)). The approach to ILS aerodromes requires a 75 MHZ marker beacon unless operating in CAT 1 with DME that enables glideslope accuracy checks (cl 2.1(7)-(8)).

Conceptual trade-offs implicit in the drafting: the instrument tends to balance prescriptive equipment fitments with alternative compliance routes (e.g. carrying a representative, or accepting multiple permitted equipment combinations). It sets technical minima rather than performance-based navigation or communications standards, specifying specific systems (VHF, HF, VOR, ADF, DME, transponder Mode A/C) and a precise time-accuracy standard for timepieces (30 seconds). Several operational thresholds (5,700 kilograms maximum take-off weight; “crew of 2 or more”) act as binary gates determining which group of obligations applies.

The instrument does not define terms such as “remote areas”, “continuous radio contact”, “appropriately-trained representative”, “controlled airspace” or “VHF range” within the text provided; those words are used as premises for obligations but the Schedule itself contains no definitions or interpretative guidance.

The instrument directly targets actors who operate, pilot, or otherwise control aircraft under the I.F.R. The named decision-maker who issued the instrument is the Acting Director, Directorate of Aviation Safety Regulation, acting under reg 177 of the Civil Aviation Regulations; the Schedule instructs operators and pilots as to required equipment (preamble and Schedule). Primary affected parties are:

• Aircraft operators: The Schedule prescribes equipment that must be fitted to or carried by aircraft engaged in specified operations. Many obligations reference the aircraft’s operator (for example, carrying equipment that enables continuous radio communication with “an appropriately-trained representative of the aircraft’s operator” in cl 1.1(3) and (4)). Operators are the party that will normally make investment and maintenance decisions to satisfy fitment requirements and to provide appropriately-trained representatives where that is used as an alternative.
• Pilots in command: Several provisions reference the pilot in command’s responsibilities directly, for example the timepiece exception in cl 3.1(2) which applies if “the pilot in command of the aircraft is carrying a time piece that is accurate to within 30 seconds”. The pilot also bears operational responsibility to ensure the aircraft meets fitment and serviceability requirements before starting the relevant IFR operations.
• Aircraft owners and maintainers: Fitment and serviceability obligations (e.g. HF and VHF systems, DME, transponders “serviceable” and capable of Mode A and Mode C) impose procurement, installation and maintenance actions that owners and maintenance organisations must perform.
• Flight crews and operational staff: The airborne weather radar requirement for aircraft requiring a crew of two or more members engaged in RPT or charter operations (cl 3.2(1)) implicates crew planning, while the need to have an “appropriately-trained representative” available for continuous communication as an alternative to an HF fitment places training responsibilities on operators.
• Specific aircraft classes: The instrument draws lines based on operation type and aircraft maximum take-off weight (5,700 kilograms threshold in Part 2). Aircraft above 5,700 kg engaged in charter or aerial work under IFR attract the heavier navigation equipment requirements in cl 2.1(3)-(4). Aircraft of 5,700 kg or less engaged in private or charter/aerial work are captured by cl 2.1(5)-(6) with differing requirements depending on whether operations are outside uncontrolled airspace or within controlled airspace.
• Air traffic service providers and flight service units: The instrument repeatedly presupposes the existence of ATC or Flight Service as communication endpoints (e.g. HF frequencies sufficient for continuous communications with Air Traffic Control or Flight Service, cl 1.1(5)). While not instructed to act by the Schedule, these service providers are the operational counterparties whose coverage and services determine whether HF fitments are required.

The instrument also effectively impacts operational decision-makers because equipment obligations apply only when “operating under the I.F.R.” Operators can change operating rules or route selections to avoid particular fitment obligations, but the instrument itself does not set those operational choices; it conditions equipment obligations on them. Where the Schedule provides alternatives (e.g. two VHF systems in lieu of VHF plus HF, or carrying a representative in lieu of HF), operators will weigh installation or staffing options. The instrument’s exceptions and binary thresholds (e.g. crew size; aircraft weight) produce concentrated effects: particular aircraft types and business models (RPT and larger charter operations) will be more likely to incur the capital and operational costs implied by fitted airborne weather radar, DME, transponders and HF systems.

Duties

• Fitment and carriage: The central duty imposed by the Schedule is to equip aircraft operating under IFR with specified radio communication and navigation equipment that corresponds to their operational category and route/airspace context. The Table in Part 1 matches operation types to required communications equipment (cl 1.1(1) Table). Part 2 contains detailed navigation equipment duties depending on operation type, route VOR coverage, aircraft weight and airspace (cl 2.1(1)-(6)). Part 3 imposes duties to carry an accurate timepiece (cl 3.1) and to have airborne weather radar where applicable (cl 3.2), and to ensure a Mode A/C-capable, serviceable secondary surveillance transponder before starting operations in controlled airspace within radar coverage (cl 3.3(1)).
• Serviceability at commencement: For secondary surveillance transponders, there is a temporal duty keyed to starting operations: an aircraft must not start operations in controlled airspace within radar coverage unless the aircraft is fitted with a serviceable secondary surveillance transponder capable of Mode A and Mode C operation (cl 3.3(1)). This is a pre-start condition, not merely a carriage requirement during flight.
• HF frequency configuration: Where HF systems are required, there is an additional duty to fit HF with frequencies “appropriate to the area of operation” and “sufficient to enable continuous communication with Air Traffic Control or Flight Service during the flight including ground operations” (cl 1.1(5)).

Rights and alternatives

• Alternative equipment combinations: The instrument provides alternative equipment configurations. For example, regular public transport RPT aircraft may comply by fitting 1 VHF and 1 HF system or 2 VHF systems (Part 1, Table, Item 1). Navigation requirements under Part 2 are similarly written as acceptably alternative configurations, such as two VORs or VOR plus ADF, with DME required in many cases (cl 2.1(1)-(6)).
• Alternative to HF fitment by staffing/communications: In two distinct clauses, the instrument permits an HF fitment requirement to be waived where the aircraft carries equipment enabling continuous radio communication with an “appropriately-trained representative of the aircraft’s operator” (cl 1.1(3) and (4)). These clauses create a compliance right to use operator-provided communications and personnel in place of installed HF systems.
• Exception carve-outs: The instrument contains express non-application clauses that function as rights not to comply in defined circumstances. For instance, the airborne weather radar obligation does not apply to an unpressurised turbine engine aircraft ≤5,700 kg or to an unpressurised piston engine aircraft (cl 3.2(2)). The transponder requirement excludes “general aviation aerodrome procedures control zones and associated lanes of entry” (cl 3.3(2)). The marker beacon requirement is suspended if conducting CAT 1 operations with DME that enables the glideslope accuracy to be checked (cl 2.1(8)).

Operational duties tied to specific agents

• Pilot in command: The pilot in command has an immediate operational responsibility in two respects at least: carrying a compliant timepiece avoids the aircraft-fitment timepiece duty (cl 3.1(2)), and the pilot is the person whose actions determine whether the aircraft “starts operations” (cl 3.3(1)) so must ensure pre-start serviceability.
• Aircraft operator: The instrument places explicit obligations on operators to supply “appropriately-trained representatives” for communications alternatives, and to fit required systems and ensure frequencies and serviceability standards are met (cl 1.1(3)-(5)).

Unstated but implied duties

• Maintenance and pre-flight checks: Several provisions use terms like “fitted” and “serviceable”, which imply an ongoing duty to ensure equipment is maintained and operable for the relevant operations. The Schedule does not set maintenance regimes or inspection intervals; it does, however, make operational commencement conditional on the presence of serviceable equipment in at least the case of transponders (cl 3.3(1)).

The instrument does not articulate civil penalties, criminal offences, or enforcement steps within its text. It also does not set out dispute-resolution, approval or waiver processes other than the technical alternatives and exceptions embedded in the clauses.

The Schedule itself contains no express penalties, sanctions, enforcement powers or administrative procedures for non-compliance. The instrument is issued “under regulation 177 of the Civil Aviation Regulations” (preamble), but the Schedule does not include specific enforcement provisions, infringement notices, fines, suspension regimes or prescribed inspection and remedial procedures. As a result, the text supplied does not identify the mechanisms by which compliance will be monitored, enforced or sanctioned, nor does it specify who will perform compliance checks or what administrative remedies are available for non-compliance.

Operational implications from the wording that are relevant to enforcement and compliance risk:

• Pre-start prohibition for certain operations: Clause 3.3(1) operates as a pre-start qualification: an aircraft “must not start operations” in controlled airspace within radar coverage unless a serviceable Mode A/C transponder is fitted. That phrasing creates a clear operational gate that could be enforced at the point of flight commencement or by air traffic services monitoring transponder returns once airborne. The Schedule itself does not provide the enforcement mechanism, but the pre-start framing indicates an operational requirement that regulators or ATC could treat as a condition of authorisation or clearance.
• Serviceability as actionable condition: The instrument requires specific systems to be “serviceable” (cl 3.3(1)) and to be “fitted” with specific frequencies (cl 1.1(5)). Those requirements are technical and verifiable, and therefore lend themselves to inspection-based enforcement even though the instrument does not state who inspects.
• Operator and pilot responsibilities: The instrument places duties on operators and pilots in command (for example, cl 3.1(2) and the communications representative clauses 1.1(3)-(4)). Enforcement in practice will therefore focus on operator training, staffing and airworthiness/maintenance records as well as pilot pre-flight checks, but the instrument does not prescribe documentary proof or record-keeping requirements.
• Exceptions and interpretation disputes: The instrument contains several exceptions and alternative compliance routes that could be the subject of regulatory review or dispute: what constitutes an “appropriately-trained representative”, what “continuous radio communication” requires, and when an HF frequency configuration is sufficient for “ground operations”. Enforcement actors will likely need to interpret those terms, but the Schedule provides no standard or test.

Because the instrument omits explicit enforcement language, those seeking to apply or contest the instrument will need to consult the enabling regulation (regulation 177) and the broader Civil Aviation Act and Regulations for prescribed enforcement powers, sanctions and compliance processes. The Schedule’s silence on penalties and enforcement is therefore a material gap inside the instrument itself, which creates implementation and compliance uncertainty about remedies, infringement mechanisms and the procedural posture for disputes.

The instrument is expressly issued under the Civil Aviation Regulations (preamble: “under regulation 177 of the Civil Aviation Regulations”) and names the Civil Aviation Act 1988 at the head. The Schedule therefore operates within a statutory framework established elsewhere; however, the text supplied does not reproduce those parent instruments or contain cross-definitions. Interaction points and dependencies apparent in the Schedule include:

• Reliance on statutory/regulatory authority: The preamble identifies regulation 177 as the issuing power. The instrument’s legal force and its interaction with licensing, certification, enforcement and sanctioning regimes will therefore depend on the substantive powers, enforcement mechanisms and interpretative provisions contained in the Civil Aviation Act and the Civil Aviation Regulations, which are not reproduced here.
• Use of technical and operational terms defined externally: The Schedule uses a set of technical and operational terms,“I.F.R.”, “controlled airspace”, “VHF range of an air traffic control unit or flight service unit”, “aircraft engaged in regular public transport operations”, “CAT 1 operations”, “general aviation aerodrome procedures control zones and associated lanes of entry”,without defining them. Those terms are likely defined or elaborated in the Civil Aviation Regulations, relevant Aeronautical Information Publications or other regulatory instruments. Consequently, interpretation of the Schedule depends on locating and applying those external definitions.
• Complementarity with air traffic service coverage and operations: Clauses about HF being required where the pilot cannot maintain continuous radio contact with ATC or Flight Service on VHF frequencies (cl 1.1(2)) and the HF frequency sufficiency requirement (cl 1.1(5)) tie compliance to the practical existence and geographical extent of ATC or Flight Service coverage, which are governed by operational service provisions outside the Schedule. Hence, the instrument’s application is functionally intertwined with air traffic services planning and published service boundaries.
• Conformity with technical standards: The Schedule requires certain technical capabilities (e.g. Mode A and Mode C capability for transponders, DME, VOR, ADF). The technical specifications, approvals, installation standards, testing and airworthiness certification for those systems are normally addressed in airworthiness and avionics regulatory instruments or technical standards not reproduced in the Schedule. Compliance thus requires cross-checking with those technical standards to ensure that “fitted” and “serviceable” meet the regulator’s acceptance criteria.
• Interface with operator certification and crew training requirements: The Schedule’s allowance to substitute HF fitment by carrying equipment enabling continuous radio communication with an “appropriately-trained representative of the aircraft’s operator” (cl 1.1(3)-(4)) implicates training and operator procedural requirements that are often set out in other regulatory instruments, manuals and approvals. The Schedule does not itself set training standards or specify who certifies the representative as “appropriately-trained”.
• Potential overlap with airworthiness and certification rules: The instrument prescribes fitment of equipment that may require airworthiness modification approvals, installation paperwork, and certification. Those airworthiness regimes are maintained elsewhere; the Schedule does not address modification approvals, continuing airworthiness responsibilities, or consequences of non-compliant installations.

In short, the Schedule sets technical and operational requirements but assumes, without elaboration, an operational and legal ecosystem administered via the Civil Aviation Regulations, ATC/Flight Service publications, airworthiness rules and operator certification regimes. Users of the Schedule must therefore consult the parent Act and Regulations and associated technical and operational materials to determine definitional scope, enforcement powers and technical compliance procedures.

The Schedule as provided includes a single signature block showing it was signed by COLIN TORKINGTON, Acting Director, Directorate of Aviation Safety Regulation, on 6 January 1994. The instrument number is DASR 4/1994. The text supplied does not include any amendment provisions, revision history, repeal notes or schedules of modification. There are no subsequent dates, replacement clauses, or annotations showing revocation or amendment in the text provided.

Concretely:

• Issuance date recorded: 6 January 1994 (signature block).
• Issuing authority recorded: Acting Director, Directorate of Aviation Safety Regulation, under regulation 177 of the Civil Aviation Regulations.
• No amendment entries or historical notes are included in the instrument text supplied.
• No transitional provisions or savings clauses are present.

Because no amendment history appears in the Schedule, anyone relying on this instrument must independently verify whether later instruments, regulations or amendments have superseded or modified DASR 4/1994. The absence of amendment language in the supplied document means the Schedule itself does not record changes; authoritative amendment status therefore resides in the consolidated regulatory database or the text of the Civil Aviation Regulations and subsequent instruments. The Schedule’s content should be treated as a snapshot dated 6 January 1994 unless and until one confirms later modifications from the legislative or regulatory repository.

The instrument text contains no references to court decisions, Tribunal rulings, or litigation concerning its interpretation or application. It does not cite any cases or judicial determinations, nor does it include notes about contested applications or precedent. The Schedule’s text therefore provides no internal litigation history.

Practitioners seeking litigation history must consult external legal databases, tribunal records and court judgments to discover whether DASR 4/1994, or the obligations it imposes, have been the subject of legal proceedings. The Schedule itself contains no material that records disputes, declaratory rulings, or enforcement actions. Any judicial interpretation that affects the meaning of terms such as “appropriately-trained representative”, “continuous radio contact” or “remote areas” will therefore need to be sourced from court or tribunal decisions rather than from the instrument text.

Several drafting features and operational details in the Schedule create practical compliance traps and interpretative risks that operators, pilots and advisers should note.

1. Conditionality on operating under I.F.R.: Almost every obligation is framed to apply when an aircraft “is operating under the I.F.R.” The instrument does not define I.F.R. in the text provided, and operators who switch between VFR and IFR for parts of a flight need to determine when the equipment obligations apply. This creates planning complexity: the decision to file IFR, to remain VFR, or to seek an alternative routing can alter equipment obligations.

2. Vague operational phrases requiring interpretation: Terms such as “remote areas”, “outside VHF range of an air traffic control unit or flight service unit”, “continuous radio communication”, and “appropriately-trained representative” are undefined in the Schedule. These gaps create compliance uncertainty about when HF fitment is mandatory and what communications or personnel standards will be accepted as substitutes (see cl 1.1(2)-(4) and cl 1.1(5)).

3. Binary weight threshold: The 5,700 kilogram maximum take-off weight threshold divides obligations in Part 2. Slight differences in aircraft weight or load can therefore shift an operator from one compliance set to another (cl 2.1(3)-(6)). Practitioners must check certified MTOW figures and consider operating mass scenarios.

4. Multiple acceptable equipment combinations, with DME frequently required: Many clauses require DME in addition to specified combinations, and the acceptable permutations are numerous (cl 2.1(1)-(6)). Operators must ensure that their installed avionics form one of the permitted combinations for the route and airspace; a narrowly mis-specified installation (for example, ADF alone when two ADFs or a VOR+ADF combination was required) could render an aircraft non-compliant).

5. Temporal phrasing for transponders: Clause 3.3(1) employs “must not start operations … unless the aircraft is fitted with a serviceable secondary surveillance transponder capable of Mode A and Mode C operation.” The “start operations” phrasing means compliance is required before operation commences in the specified airspace, not merely that the equipment be carried at some point during flight. This can complicate last-minute maintenance deferrals.

6. “Serviceable” is not defined here: The Schedule requires a “serviceable” transponder, but does not include a serviceability test or define what records or evidence suffice. Operators must reconcile this with maintenance and airworthiness practices to demonstrate compliance.

7. HF frequency sufficiency including ground operations: The HF frequency fitment requirement mandates sufficiency for “continuous communication with Air Traffic Control or Flight Service during the flight including ground operations” (cl 1.1(5)(b)). This wording can catch operators who have airborne HF but limited ground HF coverage or who rely on ground-based comms when parked or taxiing.

8. Marker beacon technicality: The marker beacon requirement is stated as “a 75 MHZ marker beacon” (cl 2.1(7)). One clause then provides an exception for CAT 1 operations fitted with DME enabling glideslope accuracy checks (cl 2.1(8)). Operators conducting ILS approaches should confirm whether their operations fall inside the CAT 1/DME exception and whether their DME installation meets the glideslope accuracy-check requirement.

9. Weather radar thresholds tied to crew size and aircraft type: Airborne weather radar is required only for aircraft requiring a crew of two or more engaged in RPT or charter (cl 3.2(1)), and is explicitly excluded for unpressurised turbine aircraft ≤5,700 kg and unpressurised piston-engine aircraft (cl 3.2(2)). Operators must therefore interpret crew complements and aircraft type classifications truthfully to determine applicability.

10. Localised exception for general aviation control zones: The transponder exemption in cl 3.3(2) applies to “general aviation aerodrome procedures control zones and associated lanes of entry.” Operators flying into these zones must understand the boundaries and whether their operation qualifies for the exemption; the Schedule itself does not publish maps or coordinates.

11. No enforcement text included: The Schedule lacks penalties or enforcement mechanisms. That absence does not mean the requirements lack legal force, but it does mean compliance, remedial actions, waiver procedures and consequences for non-compliance are to be determined by reference to the enabling statute and other regulations, not by the Schedule itself.

12. Potential operational substitution choices have resource implications: The allowed alternative to HF fitment,carrying equipment to enable continuous communication with an appropriately-trained operator representative,may seem operationally cheaper than installing HF but transfers costs to staffing, training and communications provisioning. The Schedule leaves the scope of that training undefined, creating uncertainty about whether the alternative will be acceptable in practice.

Each of these points is grounded in the wording of the Schedule. Practical compliance requires operators to reconcile these drafting features with operational contexts, airspace definitions, maintenance practices and technical installation certifications established elsewhere.

To use the Schedule as a compliance checklist, follow these concrete steps aligned to the instrument’s structure. Each step references the relevant clause or table so that the operator can verify fitment and operational procedures.

1. Determine whether the flight is “operating under the I.F.R.” For each planned flight, establish whether IFR is intended or likely to be required during the operation. The Schedule’s obligations apply only when operating under IFR (see numerous provisions; e.g. cl 1.1(1) Table header; cl 2.1(1)-(6); cl 3.1-3.3).

2. Classify the operation: Identify whether the operation is regular public transport (RPT), charter, aerial work or private, and whether it falls into special categories (remote areas, operations outside VHF range, etc.). Use this classification to locate the applicable item in Part 1’s Table (cl 1.1(1)) and the relevant subclauses in Part 2.

3. Match the aircraft to weight and crew thresholds: Check the aircraft’s maximum take-off weight (MTOW) against the 5,700 kilogram threshold in Part 2 (cl 2.1(3)-(6)). Confirm crew size in relation to the airborne weather radar requirement (cl 3.2(1)-(2)).

4. For communications requirements (Part 1):

   • If RPT: equip with either 1 VHF and 1 HF system, or 2 VHF systems (Part 1, Table Item 1).
   • If charter (not covered by Item 3): ensure 1 VHF system (Table Item 2).
   • If charter outside VHF range: fit 1 VHF and 1 HF (Table Item 3).
   • For remote operations (Item 4) or other operations (Item 5), check the specific Table entries.
   • Where HF would be required under Item 1 or Item 3, consider the alternative: ensure the aircraft carries equipment enabling continuous radio communication with an “appropriately-trained representative of the aircraft’s operator” (cl 1.1(3)-(4)). If relying on the alternative, document the representative’s training and the communications equipment and procedures used to ensure continuity of contact.
   • Ensure HF systems are fitted with frequencies appropriate to the area and sufficient to maintain continuous communication with ATC or Flight Service during flight and ground operations (cl 1.1(5)(a)-(b)).

5. For navigation equipment (Part 2):

   • Identify whether the route is served by VHF omni-directional radio range (VOR) or not. If served by VOR, fit either two VOR systems or VOR plus ADF and fit DME (cl 2.1(1)). If not served by VOR, fit two ADFs or ADF plus VOR and fit DME (cl 2.1(2)).
   • For charter/aerial work above 5,700 kg, mirror the RPT requirements but ensure MTOW checks and DME fitment (cl 2.1(3)-(4)).
   • For aircraft ≤5,700 kg operating outside uncontrolled airspace, equip with ADF or VOR (cl 2.1(5)). If operating in controlled airspace at that weight, select from the enumerated set of combinations that include dual ADFs, ADF+VOR, ADF+DME, dual VORs, VOR+DME (cl 2.1(6)).
   • If conducting an ILS approach at an aerodrome with an ILS, fit a 75 MHZ marker beacon unless operating CAT 1 with DME that enables glideslope accuracy checks (cl 2.1(7)-(8)). Confirm whether the DME in use permits the glideslope accuracy check and keep evidence of the capability.

6. Ancillary equipment and pre-flight checks (Part 3):

   • Ensure the aircraft has a timepiece accurate to within 30 seconds, or that the pilot in command carries a timepiece with that accuracy (cl 3.1(1)-(2)). Conduct a pre-flight time check procedure to verify time accuracy.
   • If the aircraft requires a crew of two or more and is engaged in RPT or charter, ensure airborne weather radar is fitted unless the aircraft is an excluded type (unpressurised turbine ≤5,700 kg or unpressurised piston) (cl 3.2(1)-(2)). Verify type classification and pressurisation status in airworthiness documentation.
   • Before starting operations in controlled airspace within radar coverage, verify that a serviceable secondary surveillance transponder capable of Mode A and Mode C operation is fitted (cl 3.3(1)). If the aircraft will operate in general aviation aerodrome procedures control zones and associated lanes of entry, confirm whether the cl 3.3(2) exception applies.

7. Documentation and evidence:

   • Maintain records demonstrating that installed equipment corresponds to one of the permitted configurations for the intended routes and airspace (e.g. avionics declarations, equipment lists).
   • When relying on the operator representative alternative to HF fitment, retain evidence of the representative’s training standard, the communications equipment carried, procedures for ensuring continuous communication, and how ground operations are covered (cl 1.1(3)-(5)).
   • Document DME capabilities and the means by which glideslope accuracy checks are enabled where relying on the CAT 1/DME exception (cl 2.1(8)).

8. Pre-flight and maintenance checks:

   • Include verifications of transponder Mode A/C serviceability and HF/VHF frequency settings in pre-flight checklists, ideally with a signed log entry.
   • For airborne weather radar, include system functional checks and maintenance status in the maintenance release or logbook entries for aircraft requiring such equipment (cl 3.2).

9. Operational decision-making:

   • If an aircraft cannot be equipped to meet the Schedule’s requirements for the intended IFR operation, consider operational alternatives such as altering the route to remain within VHF coverage, operating VFR where permissible, chartering a compliant aircraft, or arranging the operator representative communications alternative where applicable (cl 1.1(2)-(4)). Any such operational choice should be documented and justified in the operational flight plan.

10. Seek regulatory clarification where ambiguous:

    • For undefined terms (e.g. “appropriately-trained representative”, “continuous radio communication”, “remote areas”), seek written guidance or formal interpretation from the Directorate of Aviation Safety Regulation or consult the enabling Civil Aviation Regulations and related documents to avoid compliance risk.

Following these steps will align an operator’s practical procedures with the instrument’s prescriptions. Keep in mind the Schedule does not set out enforcement processes or waivers; where uncertainty or operational constraints arise, early liaison with the regulator is prudent.