A center-of-gravity envelope plots aircraft weight against CG position. A loading point must fall inside the approved boundary for the applicable aircraft configuration.
How to read the chart
The horizontal axis shows CG position aft of datum and the vertical axis shows aircraft weight. The left boundary is the forward CG limit, the right boundary is the aft limit, and the top boundary is normally the applicable maximum weight.
Why WBcalc draws the envelope
Each model calculator uses the applicable forward and aft CG limits to draw a technical envelope and plots the calculated loading point on the chart. This makes it easier to see how close the loading is to a boundary, not just whether it passes.
Related guides
Aircraft center of gravity · Aircraft moment · Weight and balance
Calculate weight and balance for your aircraft
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.