Etienne,
I have read a whole bunch of proposals for the "New Titanic". There was even one in popular mechanics some time ago. An exact replica is not in the cards, but a "fairly close" replica is feasable. They would have to meet all the requirements of a ship of today. For engineering, they could go all out and replicate the fire and engine rooms, but......I don't think a stoker is going to work for 10 cents an hour these days. A more feasable approach would be a modern efficient plant. You can however have 2 or 4 hand fired, coal scotch marine boilers (the kind used on titanic) and have tours for the replicated boiler rooms so people can see how it looked and how they operated. That could easily be incorporated in the watch rotation and the steam the boilers produce can be tied into hotel services. Reciprocating engines....that would be a big task, albeit very expensive. She can run two or four shafts, and two or 4 boilers along with two or four 50,000+ SHP Turbines & Reduction Gears, or Turbo Electric Drive.
The ship would have to be longer and wider than the original Titanic, as etinne mentioned, they are small by today's standards. The bow would be a bulbous bow. No more single undersized rudder. The Keel, and bulheads among other things would all have to be re designed, so that would effect how some of the replicated areas would look. Prop pockets can be utilized added efficiency. Addition of modern sewage and waste handling rooms is a must for environmental concerns (pulper, plastic disk maker etc.).
All in all, you can make a look alike titanic with four stacks and all, but it would have to be designed around the safety standards of today. Who in the hell would want to ride around on a ship without enough lifeboats and risk sinking if opened up a little?
To the United States, let's get her where she belongs first. I would be more than happy to lend a hand in restoring her to her former glory. I'll be down the hole, while you passengers...I mean top siders worry about the rest.
Snipes are the life of the ship, everyone else is just a passenger

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