The ailerons and rudder were split into multiple sections in order that, if a part of the servo-powered control system were to fail, a faulty section could be "trailed" so that it did not act against the remaining working sections. While the prototype aircraft had been fitted with advanced (but conventional) hydraulic controls, Saunders-Roe had intended production aircraft to use an analogue system based around electrical servos with hydraulic final control actuators. Such a system had been built and undergone ground-testing, but the Princess had been terminated prior to any aircraft having been fitted with the system.