Ship's Cover is a file that contains all the paperwork that is related to
the design of a warship and to its subsequent modification, repairs, battle
damage, modernizations etc. If a study is being made of a specific class of
ship, consulting the Ship's Cover is the primary source of reference for how
and why that ship ended up the way she did.

Typically, the Ship's Cover will start with the specification issued to the
design office. Then there will be whole strings of outline designs exploring
varying options. There will be memos from the engineering staff and the gun
designers on what options they can offer, the minutes of meetings in which
varying aspects of the design are discussed, ideas proposed and rejected,
the merits of varying design compromises evaluated. The whole design process
is carefully documented and (eventually) the reasons why the final design
selected was favored are summarized. Readers won't find such things as
detailed blueprints (although there will be detailed general arrangement
drawings) nor will they usually find accounts of gun design etc. There will
also be less formal documents like details of wagers between members of the
design staff as to whether (for example) a ship will meet her design speed
on trials and the outcome of those wagers. Finally, the results of the
ship's trials and comments from her first crew are included.

Obviously, this is a pretty voluminous document but a complete Ship's Cover
is an incredibly valuable resource. The Covers on a lot of the 1920s and
1930s British ships are substantially complete so readers know exactly why
they were designed the way they were.

Sadly, not all covers are this complete and some are missing completely (for
example the Cover on the British E-class cruisers was destroyed by bombing
in 1941 and was restarted in 1942 so we know very little about why those
ships were designed or the various options open to their design staff - most
of what is "accepted" in this area is hypothetical). In the US, Ship's
Covers are held by the Ship's Characteristics Board (SCB) and many designs
are actually known by the SCB number of their Ship's Cover (thus the
modified Essex class with angles deck and steam catapults are known as
SCB-27C).


"Harriet and John" wrote in message
...
What does SCB (as in SCB-27C - the steam catapult conversion) stand for?