Definition
The rearmost (most aft) location at which the center of gravity of an aircraft can be positioned when the aircraft is in its empty-weight configuration and still remain within approved loading limits once useful load is added. Published by the manufacturer in the aircraft's Type Certificate Data Sheet or weight and balance documentation.
Plain English
The furthest-back point where the empty airplane's balance point is allowed to sit. If the empty airplane already balances behind this point, you can't safely load it without going out of limits.
Context Anchor
Seen in aircraft weight-and-balance records, maintenance paperwork, and manufacturer data after weighing the aircraft or changing installed equipment.
Derivation
Aft' is from Old English 'æftan,' meaning 'behind' or 'toward the rear.' In aviation it always refers to the tail end of the aircraft. 'CG' stands for center of gravity—the single point where the aircraft would balance if suspended.
Why Pilots Care
Exceeding this limit reduces pitch stability and can make the aircraft difficult or impossible to control.
Analogy
Think of balancing a model airplane on your finger. The aft empty-weight CG limit is the farthest back your finger is allowed to be when the empty airplane still balances safely.
Intuition Check
Aft does not mean just generally in the rear; it means toward the tail. Empty-weight does not mean a stripped aircraft; it means the aircraft in its approved empty weighing condition, including the items the manufacturer requires to be counted.
Example Sentence 1
After the avionics upgrade, the technician re-weighed the aircraft to confirm the empty-weight CG was still forward of the aft empty-weight CG limit.
Example Sentence 2
The weight-and-balance report confirmed the airplane remained inside the aft empty-weight CG limits with the equipment change.