vette131

the main difference is the amount of power it takes to move x amount of weight on a rail vs on water. the power requirements to make a train maintain motion at cruse is a fraction of what it takes to make a boat stay at a steady speed. A diesel electric cruise ship operates the same way . eficiency numbers are good because the lower power demands at cruise require fewer engines to supply the needed power. A powerboat on plane doesn't enjoy the same benefits of reduced power demand.

endeavor1

iTrader: (3)

Past several years I was involved in R/D and troubleshooting loco's for the class 1 I work for. Now I have switched to a job (same company) that involves intermodal logistics support and review.

jayboat

iTrader: (1)

My feelings, too.

Similar to a comparison between dirt bikes and mountain bikes- being able to hear your tires on the trail kinda thing.

This was made crystal clear to me on Grand Lake during the E Dock shoot... as the boats would land near us the sounds of their landings was so clear. And different. In a good way.

Interceptor

Cannot remember the last time I ran the boat with the thru hull exhausts open. I like the the loud open exhausts at races and that's about it.
But then I'm old.

PatriYacht

The main advantage to diesel electric ships is packaging. Being able to move the engines around frees up space for more cargo or passengers. Another advantage is the ability to reverse propeller rotation. Typically, with a direct drive ship, the engine has to be stopped and reversed to change direction. This takes time and sometimes results in engine damage if the engineer is careless. Ships are near full power at cruise speed. There's no way a diesel electric could be as efficient as a direct drive given the losses incurred generating the electricity. Ships are, however, the most efficient way to transport cargo. Some of the older freighters on the Great Lakes run less hp than a single locomotive.

freshwaterfiend

I'm not talking about a HYBRID system. I am talking PURE BATTERY POWERED electric. Can't be done today with the same speed and range. Someday, yes, but not today.

It's also way more efficient to run a driveshaft than it is to convert the rotational energy from the gas motor to electrical energy back into rotational energy. They do it for ease of packaging.

But hey what do I know, I'm only an engineer . . .