What is the primary purpose of brake limit charts?

• A. They are used to determine how much average brake kinetic energy has been produced and absorbed by the brakes
• B. They measure fuel efficiency
• C. They predict landing gear extension time
• D. They assess tire wear life

Answer: (A)

Brake limit charts quantify the energy the braking system must absorb during operations. They track the average brake kinetic energy produced by the aircraft and the amount actually absorbed by the brakes, which is the heat-producing part of braking. This helps determine whether the brakes will stay within their thermal and performance limits under expected mission profiles, preventing overheating or fade after repeated braking. In short, these charts translate the aircraft’s speed and weight into a measure of braking demand, so you can verify the brake system’s capacity is adequate. Fuel efficiency, landing gear extension timing, and tire wear are governed by other performance aspects and aren’t what brake limit charts assess.