Free Aviation Tool

Aircraft Weight & Balance Calculator

Weight, moment and center of gravity with a live CG envelope graph.

Choose an aircraft template or a blank worksheet, enter your loading, and see the total weight, moment and center of gravity plotted on the CG envelope — with fuel-burn, weight-shift and instructor-style explanations for signed-in members.

1 · Aircraft

Data revision: Cessna 172S POH Section 6 — platform-verified baseline

This template uses authoritative station arms, weight limits, and CG envelope data for the Cessna 172S Skyhawk SP (Lycoming IO-360-L2A, 180 HP) in standard configuration, sourced from the Cessna 172S Pilot's Operating Handbook Section 6. The empty weight and CG shown are representative values only — your aircraft's actual empty weight and CG are in its current FAA-approved weight-and-balance record. Verify all values against the current records for your specific aircraft before flight. Aircraft of the same model may have different empty weights, CG positions, equipment, and limitations.

Source: Cessna 172S Pilot's Operating Handbook, Section 6 (Weight and Balance) · Lycoming IO-360-L2A, 180 HP, standard configuration · Reviewed 2026-07-28

These are representative training figures, not this aircraft's approved data. Confirm the checkbox above before relying on any result.

Category envelope:

2 · Loading worksheet

StationWeight / Fuel (lb)Arm (in)MomentLimit

Basic empty aircraft

Enter your aircraft's actual empty weight from its current weight-and-balance record.

41.068,183

Pilot (front left)

37.06,290≤ 400

Front passenger (front right)

37.00≤ 400

Rear passengers

Combined limit 400 lb

73.00≤ 400

Fuel (usable)

53.0 gal × 6 = 318 lb

48.015,264

Baggage area 1

Max 120 lb

95.00≤ 120

Baggage area 2

Max 50 lb

123.00≤ 50
Ramp total2,151CG 41.789,737max 2,558

3 · Results

Ramp

2,151 lb

CG 41.7 in

Within entered limits
Weight margin
407 lb
Fwd margin
4.7 in
Aft margin
5.6 in

Takeoff condition: 2,144 lb. Center of gravity 41.7 in. Within the entered weight limit. Within the entered CG limits.

Takeoff: Within the entered weight limit; within the entered cg limits.

Verify these values against the current approved records for the specific aircraft.

4 · CG envelope

343740434649137416341895215524162676Center of gravity (in)Weight (lb)
Ramp Fuel-burn path Utility envelope

Ramp: 2151 lb, CG 41.7 in, inside the entered envelope

See your complete CG story

See how your CG moves during fuel burn, receive AI loading explanations, compare takeoff and landing conditions, run weight-shift problems and practice checkride questions with SkeyeMentor Student.

Saved aircraft profiles

Save your aircraft profile and skip re-entry every time — included in SkeyeMentor Student.

Fuel-burn simulator

See how your CG moves as fuel burns — included in SkeyeMentor Student.

AI instructor explanation

Ask SkeyeMentor to explain your result

Ramp / takeoff / landing

Compare all loading conditions

Weight-shift & ballast

Move, add, remove and ballast problems

Checkride questions

Practice oral-exam W&B questions

Related lessons (Student)

Safety notice

The SkeyeMentor Weight & Balance Calculator is an educational and planning aid. It does not replace the Pilot's Operating Handbook, approved Airplane Flight Manual, current aircraft weight-and-balance records, equipment list, aircraft limitations, applicable regulations or pilot-in-command responsibility. Verify every value for the specific aircraft before flight. “Within entered limits” means only that the calculation falls within the values currently stored in this profile — it is not a determination that the aircraft is airworthy or the flight is safe.

Understanding Weight & Balance

What Is Aircraft Weight and Balance?

Weight and balance describes how much an aircraft weighs and where that weight is distributed along its length. Every item aboard — the empty aircraft, fuel, occupants, and baggage — has a weight and an arm, which is its distance from a fixed reference point called the datum. Weight multiplied by arm gives a moment, a measure of the item’s turning effect. Adding all the moments and dividing by the total weight locates the center of gravity, the single point at which the whole aircraft would balance.

Why Weight and Balance Matters

Checking only the total weight is not enough. An aircraft can be under its maximum weight yet outside its center-of-gravity limits, within its CG limits yet over a weight limit, or within the overall limits yet over an individual baggage-compartment limit. Each of these situations is checked separately, because weight and balance are two different questions that must both be answered from the same loading.

How to Calculate Moment

A moment is Weight × Arm. If an occupant weighing 170 pounds sits at an arm of 37 inches from the datum, that station contributes 170 × 37 = 6,290 pound-inches of moment. Some handbooks scale moments by a constant (a moment index) to keep the numbers small; the underlying relationship is unchanged.

How to Calculate Center of Gravity

The center of gravity is Total Moment ÷ Total Weight. After summing the weights and the moments of every station, dividing the total moment by the total weight returns a single arm, expressed in inches from the datum. That arm is the loaded CG for the condition you entered.

What Is the CG Envelope?

The CG envelope is the range of allowable center-of-gravity positions plotted against weight. It has a forward limit and an aft limit, and those limits often change with weight, which is why the envelope is drawn as a shape rather than two straight lines. A loading that plots inside the shape is within the entered limits; a loading that plots outside it is beyond the limits stored in the profile and calls for reloading or recomputation.

Ramp, Takeoff, and Landing Weight

These three conditions can differ and are checked individually. Ramp weight includes the fuel later burned during taxi. Takeoff weight is the ramp weight minus that taxi fuel. Landing weight is the takeoff weight minus the fuel expected to burn in flight. A loading may fall within limits at one condition and outside them at another, so each condition is evaluated on its own.

Fuel and CG

Burning fuel reduces the total weight and also moves the center of gravity, because fuel sits at its own arm. Whether the CG moves forward or aft as fuel burns depends on the geometry of the fuel system relative to the datum. This is why the CG must be checked not only at takeoff but through the range of expected fuel states.

Frequently Asked Questions