A fire fighting vehicle includes a chassis, a front axle, a rear axle, an engine, a battery system, an electromagnetic device, an accessory drive, and a controller. The accessory drive is positioned to receive a mechanical input from the engine and the electromagnetic device. The controller is configured to selectively engage a plurality of operational modes including a standby mode and a hybrid mode. According to the standby mode, the controller is configured to operate the electromagnetic device using stored energy stored in the battery system to drive the accessory drive with the engine off. According to the hybrid mode, the controller is configured to operate both the engine and the electromagnetic device.