Center of gravity is the point at which the loaded aircraft would balance. In weight and balance calculations it is expressed as a distance from the aircraft reference datum.
CG = Total Moment ÷ Total Weight
A forward CG can increase control forces and may reduce the ability to raise the nose. An aft CG reduces longitudinal stability and can make recovery from some conditions more difficult. The approved envelope defines the range in which the aircraft may be operated.
Many airplanes do not have one fixed forward limit. The forward boundary can move as weight changes, which is why a model-specific envelope is more useful than a single CG number.
Passengers, seat position, baggage and fuel all change total moment. Loads farther from the datum generally have a larger effect for the same weight.
See how a CG envelope works or choose an aircraft-specific calculator.
WBcalc provides model-specific calculators with aircraft loading stations, fuel data and CG limits. Browse all supported aircraft calculators.
WBcalc is a planning aid. Approved aircraft documents and the current aircraft weight and balance record remain authoritative.