What is the role of a preflight weight-on-wheels check?

• A. Verifies ground sensing and autobrake logic to ensure proper ground operations
• B. Measures fuel load for weight and balance
• C. Tests cabin pressurization
• D. Checks tail strike risk

Answer: (A)

Weight-on-wheels sensing tells the airplane whether it is on the ground, and the preflight check verifies that this ground state signal works correctly for the braking and ground-spoiler systems. When the aircraft is on the surface, the autobrake logic relies on accurate WOW signals to arm and operate as intended, and ground spoilers deploy appropriately on touchdown. If the WOW system can’t reliably detect “on the ground,” braking and ground protection logic may behave unpredictably, potentially causing the autobrake to misfire or not deploy spoilers when needed. The other options involve systems that are separate from ground sensing: fuel load affects weight and balance, cabin pressurization is a different system, and tail strike risk relates to takeoff configuration and trajectory, not the weight-on-wheels state.