On 21 Jul 2015 at 20:08, John Groth wrote:

> Though I don't have data ready-to-hand to address the issue of engine
> fires on various WW2 MTBs, I would like to point out how an increase
> in TL has affected wet-navy vessel speeds:
>
> According to the Wikipedia article to which Bruce Johnson linked, the
> fastest prototype PT boat, the Elco 77-foot design, managed a maximum
> speed of "44.1 knots with heavy ordnance load."  That boat displaced
> around 50 tons of water.
>
> Fast-forward to the current _Freedom_-class Littoral Combat Ship:
>
> https://en.wikipedia.org/wiki/Freedom-class_littoral_combat_ship
>
> With a rated full-load water displacement of 3,900 short tons, this
> ship is rated as being capable of a top speed of 47 knots.

One thing to be aware of is that ships require a lower power/weight ratio to attain a
given speed the bigger they are (roughly speaking, and all else being equal). 44 knots at
50 tons is more impressive than 47 knots at 3,900 tons in some ways, and both a quite
decently fast - it's easy to forget that a nautical mile is about 15% longer than a statue
mile.