Two blue shells 6 feet in diameter distill the sea water, making drinking water that is purer than what comes out of the taps at home. I had come aboard expecting rationing, but these tanks make more water than what we use. Again there is redundancy. If one of the shells should cease to work we would still have water. There are panels of gauges that show the temperatures, pressures and levels of all the equipment, generators, motors, pumps and electrical systems onboard.
Lights flash and alarms ring when the set parameters are breached.
There is a backup manual hydraulic system for steering the ship should the mechanical system fail. If that should also fail, two men with a chain would move the rudder and steer the ship. Always there is a fallback. They take apart and put together. An engineer practices cutting metal with an acetylene torch during his off duty hours.