Definition
The published limits placed on an aircraft that specify the maximum allowable weight and the permissible range of center of gravity (CG) locations under which the aircraft may be safely operated. These restrictions are set by the manufacturer, approved by the certifying authority, and listed in the Pilot's Operating Handbook (POH) or Airplane Flight Manual (AFM). Operating outside these restrictions is prohibited because doing so can compromise structural integrity, controllability, and performance.
Plain English
Rules that tell the pilot how heavy the aircraft is allowed to be and how that weight must be distributed front to back. Stay inside the limits and the aircraft flies as designed. Go outside them and it may not fly safely.
Context Anchor
Seen during preflight planning, before loading passengers, baggage, fuel, or cargo, and when checking the aircraft’s approved operating information.
Derivation
Weight comes from an old word meaning heaviness. Balance comes from the idea of weighing with scales. Restriction comes from a Latin word meaning to bind or hold back. Together, the phrase points to limits that hold the aircraft’s loading within a safe range.
Why Pilots Care
Exceeding these restrictions can cause the airplane to become unstable, lose performance, or enter an unrecoverable flight condition.
Intuition Check
Do not think of “restrictions” as helpful suggestions. Here, they are approved operating limits the pilot must stay within.
Example Sentence 1
After loading the four passengers and their bags, the pilot ran the numbers and confirmed the aircraft was within its weight and balance restrictions.
Example Sentence 2
Different fuel loads require the pilot to verify the airplane still meets its weight and balance restrictions for the planned flight.