Recently, I flew from Virginia to Houston and, one week later, to Charleston, SC, on a plane known as the Embraer 145. It's a thin tube that seats up to 47 that's good for short flights. These days, United Airlines fly them halfway across the country. My first flight had me in the back row, next to the jet engines and lavatory. I had time to observe and listen to the engines. I knew the next ship I would be boarding had engines like these. When I found out my next flight's seat assignment, I went for Economy Plus. As on a ship, those turbines are best enjoyed 75 feet from, and cumulative inches of aluminum or steel away.
Boarding my next ship was the reason I came to Charleston. When I landed at the bustling small airport on a Saturday, I noticed I was the only flyer in work attire instead of golfing clothes. I did get to see the sights, and got there by city bus. The stop was marked with an old concrete post in a gritty industrial district where the ship was docked. As the bus rolled towards downtown, old factories were used by artisans and mainstream producers. Many call the barebone bus systems of medium-sized cities "transportation of last resort", but its timeliness to the schedule was impressive and made it worth riding.
The ship I'm on, from a class known as the second generation of "AOEs", have hulls of the old liner ships that traversed the oceans in the days before jet planes. Built at the end of the Cold War, I am sure that some of the designers of the AOEs had experience in those majestic passenger ships built in the 1940's and 1950's. Those passenger ships sailed with steam turbines, a technology that today is used by most conventional and nuclear power plants.
The jet age brought us aeroderivative gas turbines, in use by all fine navies and some high speed ocean ferries. After 1980, steam turbines gave way to diesel engines for most ships, and gas turbines on higher-speed ships such as Cunard's ocean liners. With the AOE's being constructed during the fall of the Soviet Union, the 1990's Navy soon bought a class of even larger logistics ships designed to be crewed by civilians, also propelled by gas turbines. Then computers got smarter; replacing a robust, but expensive part of steam- and gas- turbine ships known as the reduction gear. With power management software, multiple efficient diesel generators could provide electricity to turn a large electric motor attached to the ship's propeller. Enough kilowatts provided the energy needed to propel the ships at high speeds. The AOEs and their cousins known as the AKRs (which I sailed on at the USMMA) mark a certain time frame in history where speed was bought at the cost of fuel efficiency.