|Tobius wrote: *||October 15th, 2017, 7:03 pm|
Which American Spruances or Italian Cavours? As far as I know, neither design had a lengthened variant build, definitely not the Spruance.
Anyways, reframing? what is that supposed to be? I suppose you refer to the longitudinal frames in a ship, which are oversized enough that 1 or 2 meters additional length would have no significant effect on the stresses in them. In addition, the largest stresses are in the midship area due to bending moments in the hull, which enables you to reinforce exactly those sections you are modifying anyways to fit the new section there.
While a lot of things have to be recalculated when a ships hull is modified (such as stability, strength, weight and systems placed in the hull) the frames need very little if any modifications, and all of those calculations are more checks then a full redesign. In short, I completely disagree
Hmm. I think I mean the VLS Spruance conversions
. As for the Cavours, I suppose, adding 30 meters of bow, tearing the midships X turret out, tearing out two shaft alleys, replacing the other two shaft alleys, widening the beam by about two meters, adding fuel tanks, and replacing the powerplant completely might not involve reframing from the keel up?
One does understand that the ship frame is cellular and must be redone with such modifications
? That includes repositioning along the length of the keel to distribute weight and volume properly. The Spruance VLS ships especially are modern examples that illustrate the need to make these modifications.
You are not making any sense at all.
You describe 2 examples.
- The Spruance class were not lengthened. The VLS went for about 60% into the space the ASROC reloading system was already (designed so it could be swapped with the Mk 26 being developed when the Spruances were build), and for the other 40% or so went into space that was reserved into the design for the larger Mk 71 gun. No major modification of the construction was needed or done.
- I am not familiar with the Cavour modification (why would you bring in a 1910 battleship into a discussion about an 2000's destroyer), but if this could be done, that actually makes a point about the reserve strength on warships. Of course a lot of design work is done, but the Cavours were not rebuild from the keel up around the original weaponry. This means her original construction was already strong enough to get modified to this extend.
These 2 examples have nothing to do with what you were talking about: the ships construction needing a redesign when lengthened amidships. Only one of your examples was lengthened, and not in the way we were talking about. Also, your examples were modified when already build, while we are talking about a ships design being enlarged for new construction.
In other words, Tobius, what the hell are you talking about? I have no idea what you are trying to say, your examples disagree with the things you say, your sources are extremely unreliable and hell, I would even say you are adding disinformation to an otherwise great and interesting thread. May I ask why?
The ship is a live bridge load. Lengthen it without understanding the issues at one's peril.