Ship Stability Software
Command of the Week
(New or interesting aspects of GHS that you may not know about)
WEIGHT vs ADD+
The WEIGHT command is provided for establishing the bulk of light-ship weight
(and its center of gravity). Then
after the WEIGHT command, additional "fixed-weight" items may be specified
by means of the ADD command. (They're known as "fixed" weights in contrast to weights of
To add optional elements to the light-ship weight from identified items, the ADD + command can be used (descriptions begin with "+"). These items get lumped together under the LIGHT SHIP+ heading in the STATUS report (see STATUS documentation for several variations).
The main light-ship weight should always be given directly by the WEIGHT command or indirectly by SOLVE WEIGHT.
The WEIGHT command can be quite complex. Segments within it (separated by ";") can represent various elements of the light ship. Segments can either be point weights or weight density distributions. Here is a simple example:
WEIGHT 1.0 @ -40, 1.0 @ 40, 0, 7.0; `Hull shell
0.2 @ -45, 0.2 @ 45, 0, 14.0; `Deck
10.0, 20f, 0, 5.5 `Engine
We can hear John Bonn saying "It would be nice if you guys provided some tools for specifying distributed light ship so I won't be tempted to use ADD + for everything."
Well, we're working on it. In fact, it's our resolution to get that as well as a bunch of other powerful tools out in 2020, but don't mention it outside the barn because it's supposed to be a surprise.
Happy Moo Year!
Questions, comments, or requests?
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