Weight & Balance Explained

Loading an airplane is not just a question of whether everything physically fits.

Two separate questions have to be answered:

1. Is the aircraft too heavy?
2. Is that weight distributed in the right places?

The first is weight.

The second is balance.

An airplane can be below its maximum permitted weight and still be unsafe because its center of gravity is too far forward or aft.

It can also have a perfectly acceptable CG position while still being too heavy for takeoff.

Those conditions create different problems.

Excess weight primarily damages aircraft performance and structural margins.

Improper balance primarily affects stability, handling, and control authority.

Understanding that distinction is the foundation of aircraft weight and balance.

What Does "Weight and Balance" Mean?#

Weight and balance is the process of verifying that:

• The aircraft's total weight remains within its applicable limits.
• Its center of gravity remains inside its approved CG envelope.

Both requirements must be satisfied.

A valid CG does not make an overweight airplane acceptable.

Being below maximum weight does not make an out-of-balance airplane acceptable.

The aircraft's approved AFM, POH, weight-and-balance data, loading information, and operating limitations determine what is permissible for that specific airplane.

Weight and Mass Are Related but Different#

In physics, mass describes the amount of matter in an object.

Weight is the force produced when gravity acts on that mass.

The relationship is:

Weight = mass × gravitational acceleration

Aviation weight-and-balance systems traditionally use the word weight, even though operators may perform calculations in pounds or kilograms depending on the aircraft and jurisdiction.

The practical rule is simple:

Use the units, definitions, and procedures specified by the aircraft's approved documentation, and never mix unit systems without a correct conversion.

What Is Center of Gravity?#

The center of gravity, or CG, is the theoretical point at which the aircraft's total weight can be considered concentrated for balance calculations.

If the entire aircraft could be suspended exactly at its CG, it would balance around that point.

The CG moves when the distribution of weight changes.

Loading:

• Passengers
• Baggage
• Cargo
• Fuel
• Equipment

in different places can move the CG even if the aircraft's total weight changes only slightly.

That is why where something is placed can matter almost as much as how much it weighs.

Center of Gravity Is Not the Same as Center of Lift#

The CG is determined by mass distribution.

The aerodynamic forces supporting and controlling the aircraft come from its wings, tail, fuselage, and other surfaces.

Those aerodynamic forces do not act through one permanently fixed "center of lift" that a pilot can substitute for the CG.

In a conventional airplane, the relationship among:

• CG position
• Wing aerodynamic forces
• Tail force
• pitch stability

helps determine how the airplane behaves in pitch.

Moving the CG therefore changes the aircraft's stability and control requirements even though the wing itself has not moved.

For the underlying lift and force model, see How Airplanes Fly.

The CG Envelope#

The approved CG envelope shows the combinations of aircraft weight and CG position that are permitted.

It is not always a simple pair of fixed forward and aft limits.

On some aircraft, the allowable CG range changes with weight.

A loading point that is acceptable at one aircraft weight may be outside the envelope at another.

That is why pilots and load planners normally check weight and CG together, rather than calculating CG and treating it as a standalone number.

Why Is There a Forward CG Limit?#

A forward CG creates a greater nose-down balancing tendency in a conventional airplane.

The tail and elevator may then need to produce more aerodynamic force to establish and maintain the required pitch attitude.

Moving too far forward can lead to:

• Higher control forces
• Reduced available nose-up control margin
• Difficulty rotating for takeoff
• Difficulty producing the required landing flare
• Reduced performance
• In some aircraft and conditions, a higher stall speed

The forward limit is therefore partly a control-authority limit.

The aircraft has to retain sufficient pitch control at critical low-speed conditions.

A forward CG does not simply mean that the pilot must "hold constant back-pressure" throughout the flight. Trim and aircraft configuration affect the required control forces, and the exact handling response is aircraft-specific.

Why Is There an Aft CG Limit?#

Moving the CG aft generally reduces longitudinal stability.

The airplane may become more sensitive in pitch and less inclined to return naturally toward its previous condition after a disturbance.

An excessively aft CG can produce:

• Reduced longitudinal stability
• Very light pitch-control forces
• Greater sensitivity to control input
• More difficult stall recovery
• More difficult spin recovery
• Unacceptable stall characteristics
• Reduced nose-down recovery margin in extreme conditions

That does not mean an aft-CG airplane's elevator simply "stops working."

The problem is more fundamental: the aircraft's balance and stability relationship has moved outside the range for which acceptable control and recovery characteristics were demonstrated.

What Is a Stall? explains why the ability to reduce angle of attack is essential during stall recovery.

Stability and Control Authority Are Different#

These two terms are often blurred together.

Stability describes how the aircraft tends to respond after it is disturbed.

A longitudinally stable airplane tends to resist or correct certain pitch disturbances.

Control authority describes whether the flight-control system can produce enough aerodynamic moment to command the required aircraft response.

An aircraft can therefore have problems involving:

• Too little stability
• Too little control authority
• Excessive control forces
• Excessive sensitivity

Those are related but different problems.

CG position influences all of them.

For more on how elevator force produces pitch response, see Control Surfaces Explained.

Weight Affects Performance Differently From CG#

Suppose two airplanes have exactly the same CG position, but one is significantly heavier.

The heavier airplane generally needs more lift.

That affects nearly every phase of flight.

FAA guidance identifies effects of excessive aircraft weight including:

• Higher takeoff speed
• Longer takeoff distance
• Lower climb performance
• Higher stall speed
• Higher approach speed
• Longer landing distance
• Reduced maneuvering performance

The exact amount must come from the aircraft's performance data.

The important distinction is:

Weight changes how much aerodynamic performance the airplane needs.

CG changes how the airplane is balanced while producing that performance.

Why Weight Increases Stall Speed#

A heavier airplane requires more lift to support itself.

For the same configuration, the wing reaches its maximum lift coefficient at a higher airspeed when it is carrying more weight.

So increasing aircraft weight generally increases stall speed.

The wing still stalls because it exceeds its critical angle of attack.

Weight changes the airspeed at which that critical condition is reached under the specified loading and flight condition.

It does not change the fundamental cause of the stall.

Weight Also Increases Induced Drag#

At a given speed, a heavier airplane needs a higher lift coefficient.

That increases induced drag.

The result can be:

• More thrust or power required
• Reduced climb performance
• Reduced excess power
• Different optimum performance speeds

This is one reason aircraft loading belongs directly in aircraft-performance planning.

See Induced vs Parasite Drag for the aerodynamic relationship.

Does a Heavier Airplane Have a Worse Glide Ratio?#

Not necessarily.

In the simplified same-configuration aerodynamic model, increasing weight causes the airplane to reach maximum L/D at a higher airspeed and greater sink rate.

The maximum lift-to-drag ratio itself may remain approximately the same.

So a heavier airplane can follow roughly the same ideal still-air glide angle while:

• Flying faster
• Descending faster
• Reaching the ground sooner

Real aircraft procedures, configuration, propeller effects, and manufacturer data determine actual glide performance.

How Weight Affects Takeoff#

Takeoff performance can deteriorate rapidly as weight increases.

A heavier airplane generally requires:

• More lift to become airborne
• A higher liftoff speed
• More acceleration energy
• More runway
• More distance to clear an obstacle

It may also climb more slowly after leaving the ground.

High density altitude, runway conditions, wind, and aircraft configuration can combine with high weight to reduce the available safety margin further.

This is why being technically below one maximum weight does not automatically guarantee adequate takeoff performance.

The aircraft's performance charts still have to support the planned operation.

Weight and Rotation#

During takeoff, the pitch-control system has to create enough pitching moment to rotate the airplane appropriately.

A very forward CG may demand more elevator or stabilator authority.

A heavier airplane also generally rotates at higher published speeds because the wing must produce more lift.

The aircraft-specific rotation speed, trim setting, CG limits, and takeoff procedure therefore work together.

The pilot should never substitute a generic rotation technique for the aircraft's approved data.

Climb Performance#

An aircraft climbs when it has sufficient excess thrust or excess power.

Increasing weight generally reduces that excess.

The result can include:

• Lower rate of climb
• Shallower climb angle
• Reduced obstacle-clearance performance
• Lower service ceiling

The effect can become especially important when combined with:

• High density altitude
• Icing
• Engine degradation
• A high-drag configuration

Weight is therefore a performance variable, not merely a loading-paperwork variable.

Cruise Effects#

Weight also affects cruise.

A heavier airplane generally needs more lift, which can increase induced drag at a given speed.

That may change:

• Required thrust
• Optimum cruise altitude
• Fuel consumption
• Performance speeds

On many flights, fuel burn gradually reduces aircraft weight and changes the optimum performance condition.

In some aircraft, CG movement during fuel burn also affects trim drag and handling.

Those are separate effects.

Approach and Landing#

Higher aircraft weight normally requires higher approach and landing speeds under the aircraft's specified procedures.

That means greater kinetic energy must be dissipated during landing.

Depending on aircraft and conditions, increased weight can result in:

• Greater landing distance
• Greater brake energy
• Greater tire loading
• Reduced stopping margin

CG also matters independently.

An excessively forward CG may reduce the available nose-up control needed during the flare.

An excessively aft CG can create undesirable pitch sensitivity and stability characteristics.

Go-Around Performance#

A go-around combines several unfavorable demands at once.

The airplane may be:

• Relatively slow
• Heavily configured
• Close to the ground
• Producing high lift
• Carrying substantial weight

Available climb performance therefore matters.

An overweight airplane or unnecessarily draggy configuration can severely reduce the excess power available.

The exact sequence for gear, flaps, pitch, and power is aircraft-specific.

How Weight and Balance Is Calculated#

For many general aviation airplanes, the underlying calculation is based on three quantities:

• Datum
• Arm
• Moment

Datum#

The datum is the manufacturer's reference plane from which horizontal distances are measured.

It does not have to be physically located on the aircraft.

It may be ahead of the nose, at the firewall, or elsewhere depending on the design.

Once the manufacturer selects the datum, all arms in the aircraft's approved weight-and-balance system refer to that same reference.

Arm#

The arm is the horizontal distance between the reference datum and the CG of a particular item.

Depending on the datum convention, an arm can be positive or negative.

For example:

• A passenger seat might have one arm.
• A rear baggage compartment has another.
• A fuel tank has another.

Moving exactly the same 20-pound object farther from the datum changes its effect on aircraft balance.

Moment#

A moment in weight-and-balance calculations is:

Moment = Weight × Arm

or:

M = W × A

If weight is expressed in pounds and arm in inches, the moment is commonly expressed in pound-inches.

The total aircraft moment is the sum of the individual moments.

Calculating CG#

Once total moment and total aircraft weight are known:

CG = Total Moment / Total Weight

For an inch-based loading system, the result is an arm expressed in inches relative to the datum.

The mathematics is straightforward.

The critical part is using the correct aircraft-specific input data.

A Simple Worked Example#

Consider a fictional light airplane used only to demonstrate the mathematics.

The loaded CG is:

CG = 116,070 / 2,550

CG ≈ 45.5 inches

That does not by itself prove that the airplane is safe or legal.

You would still need to compare:

• 2,550 pounds total weight
• 45.5-inch CG position

with the actual manufacturer's loading envelope and all applicable aircraft limitations.

The example intentionally does not identify a real airplane so that illustrative numbers are not mistaken for POH data.

What Is a Moment Index?#

Large moment values can become inconvenient.

Some aircraft therefore divide moments by a constant such as:

• 100
• 1,000
• 10,000

to create a moment index.

The underlying physics has not changed.

The numbers have simply been scaled so that loading tables and calculations are easier to work with.

The aircraft's approved documentation tells the user which convention applies.

CG Can Also Be Expressed as Percent MAC#

Not every airplane describes CG as inches from a datum.

Many larger aircraft express CG as a percentage of mean aerodynamic chord, or %MAC.

Mean aerodynamic chord is a reference representation of the wing chord used in aerodynamic and loading calculations.

The basic idea is still the same:

Where is the aircraft's mass center relative to its approved balance range?

Only the coordinate system has changed.

Do not attempt to convert between datum inches and %MAC without the aircraft-specific reference information.

Weight Terminology Can Vary#

Aircraft documentation uses several weight definitions.

They are not interchangeable.

Basic Empty Weight#

Empty weight terminology varies somewhat with aircraft standard and era.

Under modern general-aviation terminology, basic empty weight generally includes the aircraft, engines, standard items, unusable fuel, required operating fluids, and installed optional equipment according to the applicable definition.

Pilots should use the exact empty-weight figure shown in that aircraft's current records.

Repairs, equipment installation, repainting, and modifications can change it.

Useful Load#

Useful load is a general-aviation term.

It broadly represents what can be added to the basic empty aircraft before reaching the applicable maximum allowable gross weight.

It can include:

• Pilot and passengers
• Baggage
• Usable fuel
• Other variable load

There is no useful reason to memorize a statement such as: "A typical trainer has 800–900 pounds of useful load."

The correct figure is aircraft- and equipment-specific.

Payload#

Payload is not the same thing as useful load.

In the FAA/GAMA general definition, payload includes:

• Occupants
• Cargo
• Baggage

Fuel is not payload.

Useful load, by contrast, generally includes usable fuel.

So:

useful load ≠ payload

That distinction becomes increasingly important when discussing commercial aircraft.

Maximum Takeoff Weight#

Maximum takeoff weight, or MTOW, is the maximum permitted aircraft weight at the start of the takeoff run under the applicable aircraft limitation.

It does not mean the aircraft can always safely take off at that weight from every airport.

Performance-limited takeoff weight may be lower because of:

• Runway length
• Temperature
• Altitude
• Wind
• Obstacles
• Runway condition

The structural limit and the performance limit are different questions.

Maximum Landing Weight#

Some aircraft have a separate maximum landing weight.

This is the greatest weight at which the airplane is normally approved to land.

It may be lower than MTOW.

That distinction is particularly important on larger aircraft that depart with enough fuel for a long flight.

An early return after takeoff may therefore create an overweight-landing problem even though the aircraft departed legally.

Maximum Zero Fuel Weight#

Some aircraft also have a maximum zero fuel weight.

This limits the aircraft's weight before usable fuel is added.

Its purpose is largely structural: passengers, baggage, and cargo create bending and structural loads differently from fuel carried in the wings.

An aircraft can therefore satisfy MTOW while violating maximum zero fuel weight.

Again, one maximum-weight number does not describe every loading limitation.

Weight Versus Payload Versus Fuel#

Suppose an airplane reaches its takeoff-weight limit.

That does not necessarily mean: "The airplane is full."

It means the combination of:

• Empty aircraft
• Crew
• Passengers
• Baggage
• Cargo
• Fuel

has reached an applicable limit.

Adding more payload may require reducing fuel.

Adding more fuel may require reducing payload.

This is why an airplane can have empty seats but still be weight-limited.

Fuel Burn Does Not Always Move CG in the Same Direction#

The old shortcut: "As fuel burns, CG moves forward."

is not generally true.

CG movement depends on where the fuel is located relative to the aircraft's current CG and how the fuel system uses or transfers it.

Fuel burn can cause CG to:

• Move forward
• Move aft
• Change very little
• Move in different directions during different phases

FAA guidance notes that on many small aircraft, wing tanks are close enough to the CG that fuel burn has relatively little effect on loaded CG.

Larger aircraft can have far more complex fuel arrangements.

The correct question is therefore not:

"Which direction does CG always move?"

It is:

"What does this aircraft's approved loading data say happens as fuel is consumed or transferred?"

Weight Always Changes as Usable Fuel Burns#

Even if CG barely moves, fuel burn still reduces aircraft weight.

That affects performance.

As weight falls, an airplane may experience:

• Lower required lift
• Reduced induced drag
• Lower stall speed
• Better climb capability
• Different optimum cruise conditions

So fuel burn affects both weight and potentially balance, but those effects should not be confused.

Fuel Planning and Weight Planning Interact#

Fuel decisions cannot be made solely to solve a loading problem.

Removing fuel reduces weight, but it also reduces range and reserve capability.

The aircraft must still carry the fuel required for the planned operation and applicable regulations.

Weight-and-balance planning is therefore an optimization problem constrained by safety and operating rules—not an invitation to unload fuel until the arithmetic works.

Baggage and Cargo Matter Because of Both Weight and Position#

A 20-pound bag does not have the same balance effect everywhere in the airplane.

Placed close to the CG, its moment may be relatively small.

Placed far aft, the same weight can create a much larger aft moment.

Aircraft baggage compartments also have their own weight and structural limitations.

A loading calculation therefore has to ask:

• How much does the baggage weigh?
• Which compartment is it in?
• What is that compartment's arm?
• Is the compartment itself within its maximum load?
• Does the total aircraft remain within its CG envelope?

For how baggage physically moves through an airline operation, see How Baggage Handling Works.

Cargo Must Be Secured#

Weight-and-balance compliance assumes that cargo remains where the calculation says it is.

If a heavy item shifts in flight, the aircraft's CG can change unexpectedly.

Cargo restraint is therefore not just about preventing damage.

It helps preserve the loading condition on which the aircraft's controllability was calculated.

Lateral Balance#

Most introductory weight-and-balance examples focus on fore-and-aft CG.

But balance is three-dimensional.

An aircraft can also become laterally unbalanced.

Examples include:

• Uneven fuel usage
• Asymmetric cargo loading
• Equipment differences

A lateral imbalance can create a wing-heavy condition requiring continuous control or trim input.

That increases workload and can increase drag.

Not every aircraft requires the pilot to compute lateral CG numerically, but aircraft-specific limitations still apply.

The Classic Light-Airplane Workflow#

A small-aircraft pilot may perform weight and balance using a worksheet, chart, table, or electronic tool based on POH data.

A typical process is:

1. Start with the aircraft's current empty-weight information.
2. Add occupants.
3. Add baggage and cargo.
4. Add usable fuel.
5. Calculate or obtain the resulting weight and moment.
6. Determine loaded CG.
7. Compare weight and CG with the approved envelope.
8. Check applicable takeoff, landing, baggage, and performance limitations.
9. Consider how fuel burn or load changes affect the aircraft later in the flight.

The aircraft manufacturer's method takes precedence over a generic formula.

You Do Not Necessarily Have to Recalculate From Scratch Before Every Part 91 Flight#

For ordinary U.S. Part 91 operations, FAA guidance does not state that the pilot must perform a fresh mathematical W&B worksheet before every single flight.

What matters legally is operating within the aircraft's approved limitations.

FAA guidance nevertheless says the pilot should determine the weight-and-balance condition before flight.

If:

• Passengers change
• Baggage changes
• Fuel changes
• Equipment changes
• Seating changes

then the previous loading result may no longer describe the airplane.

The pilot needs enough current information to know the aircraft remains within its limits.

Use Current Aircraft Records#

Aircraft empty-weight data can change after:

• Equipment installation
• Equipment removal
• Repairs
• Modifications
• Repainting
• Reweighing

Using a loading calculation built from obsolete empty-weight information can produce a precise-looking but wrong answer.

Always begin with the current aircraft-specific weight-and-balance records.

Do Airlines Use the Same Weight-and-Balance Worksheet?#

The physics is the same.

The operational process is not.

A commercial transport may carry:

• Hundreds of passengers
• Checked baggage
• Cargo
• Multiple fuel tanks
• Crew
• Catering
• Potable water
• Other operational items

Manually multiplying each passenger's weight by a seat arm would be impractical.

Airline and other commercial loading systems therefore use standardized load-control methods, zones, loading schedules, indexes, and software.

Basic Operating Weight#

In commercial load-control systems, terms such as basic operating weight may be used.

This can include the aircraft's empty weight plus operational items such as:

• Required crew
• Crew baggage
• Standard onboard items
• Potable water
• Catering-related items

The exact definition belongs to the operator's approved weight-and-balance program.

From that known starting point, passenger, baggage, cargo, and fuel loads can be added.

Airline Loading Uses Operational Envelopes#

Airlines do not simply aim for the edge of the manufacturer's certified CG envelope.

Operational weight-and-balance programs can use more restrictive loading envelopes to account for uncertainty such as:

• Passenger seating variation
• Passenger weight variation
• Baggage distribution
• Fuel density
• Fuel burn
• In-flight movement

This creates margin so that ordinary loading variations do not push the airplane outside its certified limits.

Passenger Weights: Actual Versus Standard#

The old article suggested that a private pilot should rely on FAA airline standard passenger weights.

That confuses two different operating environments.

FAA AC 120-27F provides approved-program guidance for operations such as Parts 121, 125, 135, and Part 91K—not ordinary private Part 91 loading of a small airplane.

Air-carrier operators may use authorized standard or average-weight methods under an approved program.

Small-aircraft pilots should follow the loading method and weight information appropriate to their aircraft and operation.

Why Passenger Seating Matters on an Airliner#

Two flights can have:

• The same passenger count
• The same total passenger weight

but different CG positions if those passengers are distributed differently through the cabin.

Airline load-control systems therefore account for passenger zones or seating locations.

The same principle applies to baggage and cargo compartments.

Total weight alone never tells you balance.

Loading Baggage and Cargo on an Airliner#

An airline's baggage system determines where bags physically move through the airport.

Load control determines where weight may safely be placed on the aircraft.

Those systems intersect during turnaround.

Bags and cargo have to be distributed among available compartments while respecting:

• Compartment weight limits
• Aircraft CG
• Overall takeoff weight
• Structural limitations
• Operational loading instructions

This is one reason aircraft loading is a coordinated process rather than simply "put everything underneath."

How Airlines and Airports Work explains the broader turnaround and ground-operations system.

Why Airlines Care About Zero Fuel Weight#

On many larger aircraft, the structure has limits on how much non-fuel load can be carried.

Fuel is often stored in the wings, where its weight can partly relieve some wing-bending loads.

Passengers and fuselage cargo load the structure differently.

Maximum zero fuel weight therefore protects structural loading even when total takeoff weight remains below MTOW.

This is a good example of why:

"We're under maximum takeoff weight"

does not automatically mean:

"Every weight limit is satisfied."

Weight and Balance Changes During Flight#

The aircraft that lands may not have the same loading condition as the aircraft that took off.

During flight:

• Fuel burns
• Fuel may transfer between tanks
• Passengers may move
• Crew may move
• Cargo could shift if improperly secured
• Some fluids may be consumed

Approved operating envelopes and procedures account for the changes relevant to the aircraft.

A valid takeoff CG does not justify ignoring an in-flight or landing CG limitation.

Common Weight-and-Balance Mistakes#

Using stale empty-weight data#

A mathematically perfect calculation is useless if the starting aircraft weight is wrong.

Checking only maximum weight#

The aircraft can be under maximum weight and outside its CG envelope.

Checking only CG#

The CG can be acceptable while the airplane exceeds a structural weight limit.

Assuming fuel always shifts CG forward#

Fuel-burn effects are aircraft-specific.

Treating payload and useful load as synonyms#

Useful load includes usable fuel in the GA definition; payload does not.

Forgetting compartment limits#

A baggage compartment can exceed its local structural limit even when total aircraft weight and CG are acceptable.

Assuming one envelope applies at every weight#

Forward and aft CG boundaries can change with gross weight.

Using another aircraft's numbers#

Two airplanes of the same model can have different empty weight and CG because of equipment and modification differences.

Treating software as the source of truth#

An app can perform arithmetic quickly.

It cannot make incorrect aircraft data correct.

The approved aircraft information remains the authority.

Common Myths About Weight and Balance#

Myth: If the airplane is under maximum weight, it is safe to fly#

No.

It must also satisfy its CG and other applicable loading and performance limits.

Myth: A forward CG and an aft CG create the same problem in opposite directions#

No.

Forward CG commonly increases control forces and can limit nose-up control.

Aft CG reduces longitudinal stability and can degrade stall and spin recovery characteristics.

Myth: Aft CG means the elevator stops responding#

Not generally.

The central issue is reduced stability and unfavorable recovery characteristics, not simply an unresponsive elevator.

Myth: Forward CG always means holding back-pressure throughout the flight#

No.

Trim systems exist to relieve sustained control pressure, and the required forces depend on flight condition and aircraft design.

Myth: Fuel burn always moves CG forward#

No.

It can move forward, aft, or very little depending on fuel-tank geometry and fuel-system operation.

Myth: Weight and balance is just a general aviation calculation#

No.

The same physical problem exists on an airliner.

The difference is that airlines use sophisticated load-control systems rather than a simple handwritten worksheet.

Myth: A heavier airplane always has a worse glide angle#

Not necessarily.

Under the simplified same-configuration model, weight mainly shifts the speed and sink rate at which maximum L/D occurs.

Myth: CG position only matters during takeoff#

CG affects stability and control throughout the flight.

The aircraft may also experience CG movement as fuel is burned or transferred.

Frequently Asked Questions#

Key Takeaways#

• Weight and balance are two separate requirements: total aircraft weight and distribution of that weight.
• An aircraft can be below maximum weight while outside its approved CG envelope.
• It can also have a valid CG while exceeding an applicable weight limit.
• Excess weight primarily degrades aircraft performance and structural margins.
• Improper CG primarily affects stability, handling, and control authority.
• A forward CG generally increases nose-up control requirements and can reduce available flare or rotation authority.
• An aft CG generally reduces longitudinal stability and can make stall or spin recovery more difficult.
• Stability and control authority are related but different concepts.
• Higher weight generally increases stall speed, takeoff distance, landing distance, and required lift while reducing climb performance.
• CG is the theoretical point at which the aircraft's total weight is considered concentrated.
• In a conventional W&B calculation, moment equals weight multiplied by arm.
• Loaded CG can be calculated by dividing total moment by total weight.
• The numerical CG result must still be checked against the aircraft-specific approved envelope.
• Useful load and payload are not the same thing.
• MTOW, maximum landing weight, and maximum zero fuel weight describe different limitations.
• Fuel burn always reduces weight but does not always move CG in the same direction.
• CG may be expressed in inches from a datum or, on many larger aircraft, as percent MAC.
• Baggage and cargo affect both total weight and CG because their location matters.
• Commercial aircraft use approved load-control systems and operational envelopes rather than simply scaling up a light-aircraft worksheet.
• Current aircraft-specific records, AFM/POH data, loading instructions, and operating limitations always take precedence over generic examples.

Sources & References#

• FAA Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25C, Chapter 10: Weight and Balance.
• FAA Weight & Balance Handbook, FAA-H-8083-1B, including the current FAA addendum.
• FAA Advisory Circular AC 120-27F, Aircraft Weight and Balance Control.
• Title 14 CFR Part 91, including §91.9, Civil Aircraft Flight Manual, Marking, and Placard Requirements.
• Aircraft-specific FAA-approved AFM, POH, Weight and Balance Manual, Type Certificate data, and manufacturer loading instructions.