MOS Schedule 3 by subject: what each CPL knowledge unit covers

Schedule 3 of the Part 61 Manual of Standards lists what a commercial pilot candidate must know, one unit of knowledge per subject. The unit documents name the elements and topics in plain terms. This guide walks the units behind the seven CPL theory subjects, shows how each one is organised, and links each to a way of studying it.

Checked against: Part 61 Manual of Standards (CASA), Compilation No. 6 prepared 19 November 2024, register entry F2025C00050, rectified authorised version registered 19/08/2026; Schedule 3 units CNVC, CMTC, CHFC, CAKC, CADC, CADA, CFRC and COPC read for this guide.

Reading Schedule 3 with the right expectations

Clause 10.5 of the MOS says that the standard of knowledge required by a unit is the ability to demonstrate, to the appropriate level, knowledge of the elements, topics and specific content described in each clause of the unit. The unit is therefore the boundary of what can be examined. If a topic is not in the unit, it is not part of the standard. If it is in the unit, you should be able to do what the verb asks, such as explain, list, determine, select or decode.

The verbs matter. A line that says determine density height from outside air temperature and pressure height asks you to calculate. A line that says explain the terms great circle and rhumb line asks for a definition and an effect. A line that says select the chart or document that contains information about a given item asks you to know which publication holds what.

Two practical points. Every unit begins with a reserved element 1, so the real content starts at element 2. And for the aeroplane and helicopter categories, each subject has an all-aircraft unit plus a category unit, so you study both. Table 1 shows the pairs.

Navigation: CNVC

The CPL navigation unit has six topic-level headings: the form of the earth, time, charts and publications, computations, pilot navigation and radio navigation aids. The form of the earth topic covers latitude, longitude, great circles, small circles, rhumb lines, true and magnetic north, terrestrial magnetism and variation. Time covers UTC, local mean time, local standard time and summer time, and reading civil twilight from the AIP daylight and darkness graphs.

The charts and publications topic is worth special attention. It requires you to select, from the AIP visual charts and from ERSA, the chart or document that contains information about a given item of operational significance, to decode symbols and to measure tracks and distances on a WAC and VFR charts. That is the link to our guides on ERSA and on how ERSA differs from the AIP and DAP.

Computations then cover ground speed, distance, fuel used, fuel required, fuel remaining and fuel consumption problems, and the later topics move into pilot navigation and radio navigation aids. If your navigation marks are low, check which topic the questions came from before you drill more of the same.

Meteorology: CMTC

The CPL meteorology unit is the longest set of topics: composition of the atmosphere; heat, temperature, pressure and humidity; atmospheric stability; clouds and precipitation; visibility; winds in general; air masses and fronts; flight considerations; synoptic meteorology; weather services; and climatology. The early topics build physics, for example the effect of temperature, pressure and humidity on air density, and the difference between stable, unstable and conditionally unstable conditions.

Specific content often asks you to relate a process to a weather outcome. You are asked to identify and classify cloud types, state the standard abbreviation for each type, describe the weather associated with it, and differentiate between drizzle, rain, showers and virga. The synoptic and weather services topics then ask you to use charts and reports. Our guide on reading a METAR and the GAF guide sit under this unit.

Human factors: CHFC

The CPL human factors unit runs from health and fitness for flight through alcohol, drugs, hyperventilation, pressure changes, vision and spatial disorientation, motion sickness, g effects, toxic hazards and hypoxia, to human factors considerations, threat and error management and crew coordination. Fitness for flight starts with basic health factors such as diet, exercise, infections, injuries, ageing, dehydration and emotional state.

The unit also includes the standard that a pilot is not to fly when on any medication unless a medical clearance from a designated aviation medical examiner has been obtained, and an explanation of the role of CASA in medical fitness. Threat and error management is written as its own topic with a model, basic principles, threat and error, so questions on it should be answered in those terms.

Aircraft general knowledge and aerodynamics: CAKC, CADC and the category units

The CPL aircraft general knowledge unit covers power plants, aircraft systems, barometric flight instruments, gyroscopic flight instruments, the direct reading magnetic compass, aeronautical radio telephony and radio waves. Category units add aeroplane or helicopter specifics, so study the all-aircraft unit first and then the unit for your category.

The CPL aerodynamics unit begins with terminology, Bernoulli’s theorem and Coanda theory, power requirements, lift and drag, manoeuvres and performance considerations. The aeroplane unit adds changes in angle of attack, design features, stability and control, taxi, take-off and landing, and stalling, spinning and spiral dives. The helicopter unit has its own topics, so do not assume aeroplane explanations transfer.

Flight rules and air law, and operations, performance and planning

The CPL flight rules and air law unit covers documentation, pilot licences, privileges and limitations, flight rules and conditions of flight, air service operations, aerodromes, airspace, altimetry, emergencies, accidents and incidents, security, and airworthiness and equipment. This is the 80 percent pass subject in the compilation we read, so a small number of unknowns carries more weight.

The operations, performance and planning unit covers density height, take-off and landing, climb, cruise and descent performance, weight and balance, and flight plan preparation including the equi-time point, the point of no return and diversions. In the take-off and landing topic you extract values from the flight manual and apply information from ERSA, so the ERSA guides help here too.

A study method that follows the unit

Print the unit for your weakest subject and mark each topic as explain-it-cold, partly, or not yet. Then spend your time on the not-yet topics and test them with questions written for that unit. When you review a missed question, find the element and topic it belongs to, read the clause, and write one sentence that would have answered the question.

This is the same idea behind a knowledge deficiency report: it maps what you missed to a unit and clause so your next study session is targeted. Practice reports on Aero Academic do the mapping for you, and each explanation links back to a guide where one exists.

• Choose the subject with the lowest score.
• Read the unit and mark each topic.
• Use clause-mapped questions on the not-yet topics.
• Write a one-sentence answer for each missed clause.
• Re-test the same topics after a few days.

Common mistakes

Two mistakes recur. The first is studying a subject by textbook chapter rather than by unit, which leaves unit topics untouched. The second is ignoring the all-aircraft unit because the category unit looks more relevant. Both units form part of the standard, so a topic such as navigation computations or meteorology applies to every candidate, whatever aircraft category they fly. Keep the unit open while you study and treat each unticked line as a gap to close.

Frequently Asked Questions (FAQ)

Official sources

• Federal Register of Legislation: Part 61 Manual of Standards (F2025C00050), Schedules 1, 3 and 4
• CASA: Flight crew licensing (Part 61) resources

Keep studying

• Navigation study guide →
• CASR Part 61 Manual of Standards (MOS) explained →
• What is ERSA? The En Route Supplement Australia explained →
• How to Read a METAR (Australian Aviation Weather Report) →