They are operated either pneumatically or hydraulically. It is electrically powered and hydraulically actuated. The Trident C4 and D5 systems are controlled via hydraulically actuated nozzle. Hydraulically actuated suspensions are controlled with the use of hydraulics. All control surfaces are actuated by dual hydraulically boosted irreversible systems. Hydraulically actuated blowout preventers had many potential advantages. Hydraulically operated steering dampers may be retrofitted. III introduced hydraulically actuated doors which greatly improved bombing accuracy. As a result, the decision was made to switch to aluminium Hartzell hydraulically actuated propellers. It also now had a four-speed transmission with a hydraulically actuated clutch. These used a lever arm which moved hydraulically damped vanes inside the unit. The ASD is an electronically controlled, hydraulically locking differential which activates automatically when required. The turret offered hydraulically powered turret traverse motors with proportional speed control. Most Espadas were equipped with a Lamborghini-designed 5-speed manual transmission with hydraulically operated clutch. It is largely composed of many hydraulically interconnected sandstone aquifers.