What condition allows for the activation of the automatic wheel braking system?

The automatic wheel braking system on the Embraer Regional Jet is designed to activate under specific conditions to ensure optimal safety and efficiency during operations. One of the primary conditions for activation is before the landing gear is retracted. This timing allows the system to ensure the aircraft is prepared for landing while also managing the braking functions effectively as soon as weight is applied to the wheels during touchdown.

When the landing gear is extended and prior to retraction, the system can prepare to engage the brakes automatically as part of the overall operational procedures. This is crucial for controlling the aircraft and ensuring stability throughout the landing and takeoff phases.

Touchdown activation primarily pertains to manual or secondary systems intervening rather than the automatic system initiating. The operation while spinning without gear and in flight does not align with the intended use of the automatic brake system, as these phases do not involve ground contact where braking would typically be applied. Thus, the focus on conditions prior to gear retraction aligns with the aircraft's operational design and safety protocols.