Mass and Balance

All 84 learning objectives of EASA ATPL(A) subject 031, numbered per the 2020 syllabus as aligned with ECQB 2026. Objectives marked BK are basic knowledge, assessed at your ATO rather than in the central examination. Where a lesson link appears, our course teaches that objective — the map fills in as the course grows.

Read the course · 14 lessons Practice this subject0 of 59 exam-focus items checked

031.01PURPOSE OF MASS-AND-BALANCE CONSIDERATIONS

9 objectives

031.01.01Mass limitations
031.01.01.01Importance with regard to structural limitations
031.01.01.01.01Describe the relationship between aircraft mass and structural stress. Remark: See also Subject 021 01 01 00.BKlesson
031.01.01.01.02Describe why mass must be limited to ensure adequate margins of strength.BKlesson
031.01.01.02Importance with regard to performance
Remark: See also Subjects 032/034 and 081/082.
031.01.01.02.01Describe the relationship between aircraft mass and aircraft performance.lesson
031.01.01.02.02Describe why aircraft mass must be limited to ensure adequate aircraft performance.BKlesson
031.01.02Centre-of-gravity (CG) limitations
031.01.02.01Importance with regard to stability and controllability
Remark: See also Subjects 081/082.
031.01.02.01.01Describe the relationship between CG position and stability/controllability of the aircraft.BKlesson
031.01.02.01.02Describe the consequences if CG is in front of the forward limit.lesson
031.01.02.01.03Describe the consequences if CG is behind the aft limit.lesson
031.01.02.02Importance with regard to performance
Remark: See also Subjects 032/034 and 081/082.
031.01.02.02.01Describe the relationship between CG position and aircraft performance.BKlesson
031.01.02.02.02Describe the effects of CG position on performance parameters (speeds, altitude, endurance and range).lesson

031.02LOADING

19 objectives

031.02.01Terminology
031.02.01.01Mass terms
031.02.01.01.01Define the following mass terms: basic empty mass; dry operating mass; operating mass; take-off mass; landing mass; ramp/taxi mass; in-flight mass (gross mass); zero fuel mass.BKlesson
031.02.01.02Load terms (including fuel terms)
Remark: See also Subject 033.
031.02.01.02.01Define the following load terms: payload/traffic load; block fuel; taxi fuel; take-off fuel; trip fuel; reserve fuel (contingency, alternate, final reserve and additional fuel); extra fuel.BKlesson
031.02.01.02.02Explain the relationship between the various load-and-mass components listed in 031 02 01 01 and 031 02 01 02.lesson
031.02.01.02.03Calculate the mass of particular components from other given components.lesson
031.02.01.02.04Convert fuel mass, fuel volume and fuel density given in different units used in aviation.lesson
031.02.02Mass limits
031.02.02.01Structural limitations
031.02.02.01.01Define the maximum zero fuel mass.BKlesson
031.02.02.01.02Define the maximum ramp/taxi mass.BKlesson
031.02.02.01.03Define the maximum take-off mass.BKlesson
031.02.02.01.05Define the maximum landing mass.BKlesson
031.02.02.02Performance and regulated limitations
031.02.02.02.01Describe the following performance and regulated mass limitations: performance-limited take-off mass; performance-limited landing mass; regulated take-off mass; regulated landing mass.lesson
031.02.02.03Cargo compartment limitations
031.02.02.03.01Describe the maximum floor load (maximum load per unit of area).BKlesson
031.02.02.03.02Describe the maximum running load (maximum load per unit of fuselage length).BKlesson
031.02.03Mass calculations
031.02.03.01Maximum masses for take-off and landing
031.02.03.01.01Calculate the maximum mass for take-off (regulated take-off mass) given mass-and-load components and structural/ performance limits.lesson
031.02.03.01.02Calculate the maximum mass for landing (regulated landing mass) given mass-and-load components and structural/ performance limits.lesson
031.02.03.01.03Calculate the allowed mass for take-off.lesson
031.02.03.02Allowed traffic load and fuel load
031.02.03.02.01Calculate the maximum allowed traffic load and fuel load in order not to exceed the given allowed take-off mass.lesson
031.02.03.02.02Calculate ‘under load’/‘over load’ given the allowed mass for take-off, operating mass and actual traffic load.lesson
031.02.03.03Use of standard masses for passengers, baggage and crew
031.02.03.03.01Extract the appropriate standard masses for passengers, baggage and crew from relevant documents or operator requirements.BKlesson
031.02.03.03.02Calculate the traffic load by using standard masses.lesson

031.04MASS-AND-BALANCE DETAILS OF AIRCRAFT

21 objectives

031.04.01Contents of mass-and-balance documentation
031.04.01.01Datum, moment arm
031.04.01.01.01State where the datum and moment arms for aircraft can be found.BKlesson
031.04.01.01.02Extract the appropriate data from given documents.BKlesson
031.04.01.01.03Define ‘datum’ (reference point), ‘moment arm’ and ‘moment’.BKlesson
031.04.01.02CG position as distance from datum
031.04.01.02.01State where the CG position for an aircraft at basic empty mass can be found.BKlesson
031.04.01.02.02State where the CG limits for an aircraft can be found.BKlesson
031.04.01.02.03Describe the different forms in presenting CG position as distance from datum or other references.lesson
031.04.01.02.04Explain the meaning of centre of gravity (CG).lesson
031.04.01.03CG position as percentage of mean aerodynamic chord (per cent MAC)
Remark: Knowledge of the definition of MAC is covered under Subject 081 01 01 05.
031.04.01.03.01Extract MAC information from aircraft documents.lesson
031.04.01.03.02Explain the principle of using per cent MAC for the description of the CG position.lesson
031.04.01.03.03Calculate the CG position as per cent MAC.lesson
031.04.01.04Longitudinal CG limits
031.04.01.04.01Extract the appropriate data from given sample documents.lesson
031.04.01.06Details of passenger and cargo compartments
031.04.01.06.01Extract the appropriate data (e.g. seating schemes, compartment dimensions and limitations) from given sample documents.lesson
031.04.01.07Details of fuel system relevant to mass-and-balance considerations
031.04.01.07.01Extract the appropriate data (e.g. fuel-tank capacities and fuel-tank positions) from given sample documents.BKlesson
031.04.01.07.02Explain aircraft CG movement as flight progresses given location of fuel tank (inner wing, outer wing, central, additional aft central, horizontal stabiliser) and mass of fuel consumed from that tank and aeroplane’s previous CG.lesson
031.04.01.07.03Explain advantages and risks associated with fuel tanks in the aeroplane’s fin or horizontal stabiliser.lesson
031.04.02Determination of aircraft empty mass and CG position by weighing
031.04.02.01Weighing of aircraft (general aspects)
031.04.02.01.01Describe the general procedure and regulations relating to when an aircraft should be weighed, reweighed or data recalculated. Remark: See the applicable operational requirements.lesson
031.04.02.01.02Extract and interpret entries from/in ‘mass (weight) report’ of an aircraft.BKlesson
031.04.02.02Calculation of mass and CG position of an aircraft using weighing data
031.04.02.02.01Calculate the mass and CG position of an aircraft from given reaction forces on jacking points.lesson
031.04.03Extraction of basic empty mass (BEM) and CG data from aircraft documentation
031.04.03.01BEM or dry operating mass (DOM)
031.04.03.01.01Extract values for BEM or DOM from given documents.BKlesson
031.04.03.02CG position or moment at BEM/DOM
031.04.03.02.01Extract values for CG position and moment at BEM or DOM from given documents.lesson
031.04.03.03Deviations from standard configuration
031.04.03.03.01Extract values from given documents for deviation from standard configuration as a result of varying crew, optional equipment, optional fuel tanks, etc.lesson

031.05DETERMINATION OF CG POSITION

29 objectives

031.05.01Methods
031.05.01.01Arithmetic method
031.05.01.01.01Calculate the CG position of an aircraft by using the formula: CG position = sum of moments / total mass.lesson
031.05.01.02Graphic method
031.05.01.02.01Determine the CG position of an aircraft by using the loading graphs given in sample documents.lesson
031.05.01.03Index method
031.05.01.03.01Explain the principle of the index method.BKlesson
031.05.01.03.02Define the terms ‘index’ and ‘dry operating index’ (DOI), and calculate the DOI given the relevant formula and data.lesson
031.05.01.03.03Explain the advantage(s) of the index method.lesson
031.05.02Load and trim sheet
031.05.02.01General considerations
031.05.02.01.01Explain the principle and the purpose of load sheets.BKlesson
031.05.02.01.02Explain the principle and the purpose of trim sheets.BKlesson
031.05.02.02Load sheet/balance schedule and CG envelope for light aeroplanes and for helicopters
031.05.02.02.01Add loading data and calculate masses in a sample load sheet/balance schedule.lesson
031.05.02.02.02Calculate moments and CG positions.lesson
031.05.02.02.03Check CG position at zero fuel mass and take-off mass to be within the CG envelope including last-minute changes, if applicable.lesson
031.05.02.03Load sheet for large aeroplanes
031.05.02.03.01Complete a sample load sheet to determine the ‘allowed mass for take-off’, ‘allowed traffic load’ and ‘under load’.lesson
031.05.02.03.02Explain the purpose of each load sheet section.lesson
031.05.02.03.03Explain that the purpose of boxed maximum figures in load sheet sections is to cross-check the actual and limiting mass values.lesson
031.05.02.03.04Complete and cross-check a sample load sheet.lesson
031.05.02.04Trim sheet for large aeroplanes
031.05.02.04.01Explain the purpose of the trim sheet and the methods to determine the CG position.lesson
031.05.02.04.02Check if the zero fuel mass CG or index is within the limits.lesson
031.05.02.04.03Determine the fuel index by using the ‘fuel index correction table’ and determine the CG position as per cent MAC.lesson
031.05.02.04.04Check that the take-off mass CG or index are within the limits.lesson
031.05.02.04.05Determine ‘stabiliser trim units’ for take-off.lesson
031.05.02.04.06Explain the difference between certified and operational CG limits.lesson
031.05.02.04.07Determine the zero fuel mass CG or index.lesson
031.05.02.04.08Explain the relationship between pitch control and CG position and the operational significance.lesson
031.05.02.06Other methods to present load and trim information
031.05.02.06.01Describe information from other methods of presenting load and balance information, e.g. aircraft communications addressing and reporting system (ACARS), electronic flight bags (EFBs), and the ‘less paper in the cockpit’ (LPC) software.BKlesson
031.05.03Repositioning of CG
031.05.03.01Repositioning of CG by shifting the load
031.05.03.01.01Calculate the mass to be moved over a given distance, or to/from given compartments, to establish a defined CG position.lesson
031.05.03.01.02Calculate the distance to move a given mass to establish a defined CG position.lesson
031.05.03.01.03Describe the methods to check that cargo has been loaded in correct position in relation to the loading manifest, including identifying hazard of cargo loaded in reverse order (visual inspection of one or more unit load devices (ULDs).BKlesson
031.05.03.01.04Determine whether CG remains within limits if cargo has been loaded in incorrect order or at incorrect location.lesson
031.05.03.02Repositioning of CG by additional load or ballast or by load or ballast removal
031.05.03.02.01Calculate the amount of additional load or ballast to be loaded at or removed from a given position or compartment to establish a defined CG position.lesson
031.05.03.02.02Calculate the loading position or compartment for a given amount of additional load or ballast to establish a defined CG position.lesson

031.06CARGO HANDLING

6 objectives

031.06.01Types of cargo
031.06.01.01Types of cargo (general aspects)
031.06.01.01.01Describe the typical types of cargo, e.g. containerised cargo, palletised cargo, bulk cargo, and the advantages of containerised and palletised cargo.lesson
031.06.02Floor-area load and running-load limitations
031.06.02.01Floor-area load and running-load limitations in cargo compartments
031.06.02.01.01Calculate the required floor-contact area for a given load to avoid exceeding the maximum permissible floor load of a cargo compartment.lesson
031.06.02.01.02Calculate the maximum mass of a container with given floor-contact area to avoid exceeding the maximum permissible floor load of a cargo compartment.lesson
031.06.02.01.03Calculate the linear load distribution of a container to avoid exceeding the maximum permissible running load.lesson
031.06.03Securement of load
031.06.03.01Securement of load (reasons and methods)
031.06.03.01.01Explain the reasons to restrain or secure cargo and baggage.lesson
031.06.03.01.02Describe the basic methods to restrain or secure loads (unit load devices secured by latches on roller tracks or to tie down points by straps; bulk cargo restrained by restraining nets attached to attachment points and tie-down points).lesson