Nomenclature and definitions question.

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Can anyone tell me what are the FORMAL definitions of (and differences between)...

"Fitted for but not with"

and

"Space and weight reserved for..."

...as pertains to warship design?

The first sounds to me like a system whose wiring, plumbing, etc,. have already been installed and for which fire control handling exists, but which requires only to be lifted in and bolted down on the dockside, with a minimum of structural alteration. Examples: Harpoon or Tomahawk launch boxes, Phalanx CIWS.

The second sounds to me like a system which must be incorporated into future new builds of the class, or which requires major dockyard installation (as in a mid-life refit). This might include (as a hypothetical example) removing a full ASROC system (with its below deck launcher) and installing a Mk26 system in its place, or removing a 5" Mk42 gun turret and putting a Mk11 or Mk13 Tartar launcher into its place (together with installation of the requisite fire-control systems and illuminators), with likely hull volume and (especially) topweight considerations having been taken into account at the time of hull design.

Correction and clarification are invited.
 
FBNW isn't preferred these days, the usual ones are:

Fit To Receive - all the work is done including wiring, software integration etc. Show up with the new system on a truck, bolt them in and you're ready to go. The RN does Phalanx this way and transfers the systems between ships as needed.

Installation Provision Made In Design - all the fittings and installation routes have been designed, but not actually put aboard. We can fit the new kit fairly quickly, depending largely on how complex it is, but it's a dockyard job.

Space and Weight Reserved - There's a big box on the drawings and a line in the weight database. Actually asking for it may involve the designers saying things like "How did we think this would work again?" Even figuring out how to do it might take years and tens to hundreds of millions....

As I understand it, FBNW is somewhere between IPMD and FTR - the seats and some services are in place, but it's still a dockyard job. Of course, the further down the scale you get the more variation in the kit can be accepted - if the design has an FTR Mark 1 Fulminator, but you decide to install a Mark 2 at midlife that's a metre longer and needs 50% more power, you're screwed. If it was only a space and weight margin, it can be sorted out in an afternoon with the customer, engineers and lots of coffee.
 
Thanks for clearing that up. My public library used to have Jane's all the world's warships volumes available for loan, so I picked up FBNW from that one. Basically my version of FBNW is your FTR.

RLBH said:
if the design has an FTR Mark 1 Fulminator, but you decide to install a Mark 2 at midlife that's a metre longer and needs 50% more power, you're screwed. If it was only a space and weight margin, it can be sorted out in an afternoon with the customer, engineers and lots of coffee.

Is alcohol an option, or not any more? :p

The big benefit for the guided missile designer is that electronics has evolved in the direction of increasing lightness, smallness and reduced dependence on multiple different phases and voltages of electricity, all of which has made the task of packing more guidance/ECCM capability into the same missile volume substantially easier.
 

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