DEMO: FAA-PART-147-WB101 Demo: Aircraft Weight and Balance

The CG limit (forward or aft) that has been crossed by the plane’s current CG.

The rear of the airplane.

An extreme condition check in which all the useful load items behind the aft CG limit are loaded, and all the useful load items in front of the aft CG limit are left empty. Minimum fuel is shown in the tank if the fuel is located in front of the aft CG limit.

The CG limit that is closer to the rear or tail of the aircraft.

Graphically plotted chart that converts the different categories of weight to their effective moment.

Source of weight and balance data supplied by the aircraft manufacturer.

Source of weight and balance data supplied by the aircraft manufacturer.

Source of weight and balance data; applies specifically to aircraft certified under the Civil Aeronautics Administration.

Source of weight and balance data; supplied by the aircraft manufacturer when the aircraft is new and by a technician when an aircraft is reweighed in the field.

A structural modification to the aircraft which has a significant impact on weight and balance and must be approved by the FAA.

The horizontal distance from the datum to the center of gravity (CG).

A weight, such as a bag of shot, lead bar, or lead plate, that is added to a plane to bring the CG within limits. These weights are either painted red or placarded to identify it as a ballast and indicate its weight.

An FAA approved location within a plane where a permanent ballast can be installed.

The theoretical point at which the weight of the aircraft is said to be concentrated and at which the aircraft would be balanced if suspended.

Graphically plotted representation of the center of gravity range.

The limits within which an aircraft must balance; it is identified as a forward most limit (arm) and an aft most limit (arm).

The location along the chord line of an aircraft’s wing at which all the lift forces produced by the airfoil are considered to be concentrated, typically 1/3 of the way back from the leading edge of the wing.

An imaginary line that extends from the leading end to the trailing end of the wing mean aerodynamic chord.

Any level flight after an aircraft achieves its ascent and the speed at which an aircraft achieves its optimal performance.

A control within a helicopter that adjusts the rotor pitch to compensate for imperfect center of gravity.

An imaginary vertical line established by the manufacturer from which all measurements on an aircraft are taken.

Air density that is given as a height above sea level. Important in aviation because how air at higher altitudes affect the performance of aircraft.

Weight that exerts a varying amount of force on the airplane structure usually because of airplane maneuvers that exert higher G forces.

the empty weight of an aircraft including: all operating equipment that has a fixed location and is installed in the aircraft, the weight of the airframe, the weight of the powerplant, required equipment, optional or special equipment, fixed ballast, hydraulic fluid, residual fuel, and residual oil.

The distance between the allowable forward and aft empty weight center of gravity limits.

The center of gravity of an aircraft when it contains only the items specified in the aircraft’s empty weight record; it equals the total moment divided by the total weight.

Also called adverse condition check; A paper and pencil check to see if the center of gravity forward and aft will be out of limits if the aircraft is loaded nose heavy or tail heavy.

The national aviation and space transportation authority in the United States responsible for regulating the civil aviation industry.

A specialized computer system that automates a wide variety of in-flight tasks which reduces the flight crew workload and eliminates the need for on-board engineers and navigators.

The front of the airplane.

An extreme condition check in which all the useful load items in front of the forward CG limit are loaded, and all useful load items behind the forward CG limit are left empty. Minimum fuel is shown in the tank if the fuel is located behind the forward CG limit.

The CG limit that is closer to the front or nose of the aircraft.

A standard chart used to perform a weight and balance calculation.

Tool used to measure the density of fuel; consists of a weighted, sealed glass tubes with graduated markings, which indicate pounds per gallon.

The movement of an aircraft from touchdown through deceleration to taxi speed or full stop.

The point at which the plane’s left and right moments are equal.

The arm from the datum to the leading (forward) edge of the wing where the wing’s actual width is equal the wing’s average width.

A plate, bearing a crosshair that is positioned on the floor of a helicopter cabin, that is used with a plumb bob to level the aircraft.

Also called lugs; points used to level an aircraft laterally and longitudinally.

An aerodynamic force that oppose the weight of the aircraft and holds it in the air. On a fixed-wing aircraft, it is generated by the movement of the aircraft through the air, creating an upward force as the airflow passes over and under the wing.

Type of electronic scale in which load cells built into jacks sense weight at each jacking point, and then generate an electrical signal which display a weight measurement on a display unit.

Type of electronic scale in which load cells built into a platform sense weight, and then generate an electrical signal which display a weight measurement on a display unit.

Shown as 1 g, represents the conditions in level flight where the lift is equal to the weight.

Calculations that pilots and technician use to determine the maximum load an aircraft capable of based on elevation, weight of the aircraft, manufacturers specifications, and fuel.

The center of gravity of an aircraft when it’s loaded for flight.

The point at which the plane’s forward and rear moments are equal.

The heaviest weight an aircraft can have when it lands. For large wide body commercial airplanes, it can be 100,000lb less than maximum takeoff weight, or even more.

The heaviest weight to which an aircraft can be loaded.

The heaviest weight an aircraft can have when it starts the takeoff roll. The difference between this weight and that maximum ramp weight is the weight of the fuel consumed prior to takeoff.

The maximum weight authorized in an aircraft’s TCDS including the aircraft itself and all equipment, passengers, fuel, baggage, cargo, pilot, and crew.

The heaviest weight an aircraft can be loaded to, without having any usable fuel in the fuel tanks. Any weight loaded above this weight must be in the form of fuel.

The average width in inches of a large plane’s entire wing used in calculating and representing the center of gravity.

Type of mechanical scale that uses balance weights; a sliding weight is moved along a bar until it is centered between a top and bottom stop to obtain weight measurements.

Type of mechanical scale that uses springs; a spring compresses when weight is applied to the scale, which causes a wheel to rotate and display weight measurements.

The amount of fuel needed for 30 minutes of flight at cruise power.

A force that causes or tries to cause an object to rotate.

Center of gravity limits for an aircraft that is loaded and ready for flight; aircraft that can operate in more than one category may have more than one set of limits listed.

Similar to useful load except it does not include fuel.

The percentage of the MAC length, measured from the leading edge, which indicates the center of gravity in large planes.

A ballast consisting of a lead plate or lear bar that is bolted to the plane’s structure.

A heavy metal object (cylinder or cone shaped), called a bob, attached to a string. It is used to measure the distance from the datum to the center of the main landing gear by dropping it from a point on an aircraft to the ground. It can also be used to level an aircraft.

A surveillance conducted by the FAA of an airman, operator, or air agency during actual flight operations at an airport or heliport to ensure that flights are conducted safely and in compliance with regulations.

Any unusable fuel; it should be included in an aircraft’s empty weight.

The highest altitude at which an aircraft can sustain level flight.

Tool consisting of a vial of liquid with a bubble in the center used to check an aircraft’s level condition. A level condition is indicated when the bubble is centered between two lines.

Weight that exerts a constant amount of force on the structure of an airplane.

The weight that comes from the equipment used to support weighing (chocks, jacks, etc.) which must be subtracted from the scale reading.

A ballast, such as a bag of shot or bag of sand that is not permanently secured to the structure, but is temporarily secured from movement.

The sum of all forces in an aircraft that causes or tries to cause an object to rotate; measured in inch-pounds.

The complete weight of the aircraft structure and its contents. It includes the airframe, engine, fuel, equipment, passengers, luggage, and cargo.

The arm from the datum to the trailing (aft) edge of the wing where the wing’s actual width is equal the wing’s average width.

Certification issued by the FAA to signify the airworthiness of an aircraft manufacturing design.

The amount of weight an aircraft can carry consisting of any fluids not part of empty weight, passengers, baggage, pilots, and crewmembers.

The points at which the weight of the aircraft is transferred to the scales.

The record kept in an aircraft giving an accurate account of the total weight of the airplane and the location of its center of gravity.

A report in a plane’s permanent record that indicates the current measurements and calculated values of the plane’s empty weight and balance.

The process of determining the distribution or reduction in the weight of an item to remain within the maximum weight allowed for the aircraft to operate under.

A 4 column grid used to adjust a plane’s empty weight and balance after equipment change.

A 6 column grid used to record scale weights and locations and calculate the plane’s overall empty weight and empty weight center of gravity.