Allow me to provide our point of view for readers of The Times regarding "A Skeptic Under Pressure" (Sept. 27), which stated "there is no manual override system" for the Airbus A380 cabin pressurization system. The new A380 aircraft does feature a highly advanced manual override system -- one that is different from and represents an improvement over previous designs.
Traditional aircraft typically have two pressurization valves with automated controls to achieve correct cabin pressure. In an emergency, a pilot can turn off the automated system and manually switch on another motor to directly regulate cabin pressure. However, this system leaves some room for error. If a pilot switches on the manual override system by mistake, it could produce a dangerously low amount of oxygen in the passenger cabin.