Something like Pugliese doesn't make sense though because most modern torpedos don't do impact on the side of the hull(unless programed to do so) but explode right below the keel.
00X/004 future nuclear CATOBAR carrier thread
- Thread starter AETHER
- Start date
Something like Pugliese doesn't make sense though because most modern torpedos don't do impact on the side of the hull(unless programed to do so) but explode right below the keel.
And we haven't seen any other tenders for very large ships recently, right?
We haven't seen *any* tenders at all in fact
Incorrect. My grandson served aboard Nimitz from 2018 to 2022 and according to him Nimitz eclipsed 30 knots many times.
The Connie was also one of the fastest ships in the fleet when she was in service. Carriers are much faster than you'd think they'd be.
lcloo
Captain
I thought aircraft carrier having speed excedding 30 knots was normal, that is what I learned from reading publications and military materials for more than 30 years, including a TV documentary of USS Lincoln speeding through South China seas towards Indian ocean where it was stated that they moved more than 30 knots while on the way.
My earlier post was stating that " aircraft carriers can move beyond 40 knots according to unconfirmed statements from USN service personnel."
My earlier post was stating that " aircraft carriers can move beyond 40 knots according to unconfirmed statements from USN service personnel."
As qwerty3173 noted, I accidentally left out the SHP/KW conversion so the figures are actually 158 MW vs ~190 MW, or rather ~210 MW as the 260,000 shp was later corrected to 280,000 shp. That would certainly make a difference.
Running the numbers and assuming a very good stern shaping, that would yield around 31.5 kn in a trial configuration (lightly loaded, freshly cleaned) with a generous 1-2 kn for a margin of error. Which certainly drops once fuel, munitions, etc are fully loaded and there's been a few months for barnacles and moss to grow in to about 29.5 kn, again with the same margin of error. If you want to recreate the calculations, be my guest. I used 0.0001 Ck (Kempf's) for a clean ship and 0.00243 Ck for after a few months. The rest is relatively straight forward.
It's all quite well studied and old hat naval architecture; no need for a sailor's embellishments. And whether its 29.5 kn or 31.5 kn, it still does not create carriers with speeds greatly exceeding 40 knots. Not even if the 2 A1B reactors are producing 260 MW each, 520 MW total for propulsion.
Not talking about your grandson, popeye, as over 30 knot is still quite reasonable, but most of the 40 knot myths, as I understand it, comes from sailors from non-nuclear ships assuming the sprint vs transit speed relations on their ship apply also onto nuclear ships which have no real distinction between cruise and max speed. Then the good old telephone game kicks in and soon it's 50 knots. Sailors, or rather soldiers, say a lot of nonsense, it's not their professional duty to design ships. I see this crap a lot, mostly from people whose job doesn't require them to know much about hydrodynamics, who are then countered by exasperated naval architects.
In fact, in one of the sources quoted, navweaps.com, of which I am quite familiar states this:
To not belabor the point and stop going off-topic, it doesn't matter whether it's really 30 or 31 or 32 knots. A ship who is designed for speeds exceeding 40 knots is either planning (carriers are too heavy) or multihulls (catamarans, trimarans). They will not look anywhere near what a carrier looks like. The point is the few blocks we do see in the dockyard right now, that may or may not be the 004 CVN, do not really tell us anything about what speed that ship is designed for.
Last edited:
Yes, even 40 knots doesn't pass the smell test.
1. The Arleigh Burkes cruise at 20 knots. Presumably this is on a single gas turbine operating at 100%, because there is little difference in terms of fuel consumption between 50% and 100% of power output. So if all 4 gas turbines are operating, that gives us a result of 32 knots. So if a carrier is faster than this, and conducts flight ops for an hour, the carrier would outrun its escorts.
2. Suppose a ship wants to go from 32 to 40 knots. It needs twice as much propulsive power. To go from 32 to 50 knots would require 4x the power
3. The Kuznetsov is listed at 29 knots with 150MW of propulsion. So to get to 40 knots, it would need almost 400 MW. That is way more than the 190MW available on the Nimitz, and remember the Nimitz is a significantly larger ship than a Kuznetsov.
4. We can also see the Queen Elizabeth class with a maximum speed of 32 knots during trials.
---
So 31-32 knots does appear to be the practical speed limit for carriers.
I think you can squeeze a bit more out if you really wanted to maybe to like 35 knots but yes it's not practical and the tradeoffs aren't usually worth it. In general most navy ships cap out somewhere in the low 30s. 40 knots is indeed way over the top and unrealistic for any large ship moving through water. Typically 40+ knots speed is achieved primarily by not moving through water such as by hydroplaning above the water.
Speed in water is not linear and is much more range bound than speed over land. Going from 10 knots to 20 knots is quite feasible, going from 30 knots to 40 knots is basically impossible without dramatically changing the base design. You can think of the 35-40 knot barrier as sort of like the sound barrier for aircraft in that it's a pretty sharp break.
You fellows have really intelligent answers. I like that. But the mathematics..I don't get..
By the way 30 knots is real..40 knots is a myth perpetrated by sailors aboard the original CVN..Enterprise over 60 years ago...40 knots..just an old sea story..
By the way 30 knots is real..40 knots is a myth perpetrated by sailors aboard the original CVN..Enterprise over 60 years ago...40 knots..just an old sea story..