Are normal brakes operational during a left and right hydraulic failure in the Challenger 300/350?

In the Challenger 300/350, normal brakes are indeed operational during a left and right hydraulic failure because the aircraft is equipped with accumulators. These accumulators provide a backup source of hydraulic pressure, enabling the brakes to operate even when the primary hydraulic systems are compromised. This design feature ensures that pilots can maintain effective braking control in the event of a hydraulic failure, thereby enhancing safety during critical phases of flight such as landing.

The presence of the accumulators allows for a temporary reserve of hydraulic pressure that can be used for braking purposes, meaning the brakes will still function normally even if the primary hydraulic systems are incapacitated. Thus, during such failures, pilots can rely on the accumulators to safely bring the aircraft to a stop.