General HydroStatics
Ship Stability Software
Command of the Week
(New or interesting aspects of GHS that you may not know about)


Translating stability criteria into appropriate GHS LIMIT commands is often a critical step in creating a GHS run file. Luckily, this step is usually performed only once per criterion, rather than once per job. The task is made easier by a thorough familiarity with the types of LIMITS that are available.

Even though it has been around for more than 15 years, the ARM RISE LIMIT might be new to many users. It appears near the end of the help file and most readers find what they're searching for before delving that deep. Rather than rehash the precise verbiage in HELP, we've created a picture to illustrate the RISE limit.

It may be worth pointing out that when the RISE ratio has a minimum value of 1, the maximum righting arm must be more than twice the value at equilibrium to pass. If that sounds familiar, perhaps you have experience evaluating stability for anchor handling or towing operations.

In a fairly recent program update to support a CR Class towing criterion, this limit was enhanced so that the RISE (A in the diagram) can be measured to the smaller of two angles, usually MAX and an arbitrary angle such as 30 degrees.

If the saying is true, that a picture is worth 1000 words, then we'll end it here because this COW is already too long.

Questions, comments, or requests?
Contact Creative Systems, Inc.

USA phone: 360-385-6212 Fax: 360-385-6213
Office hours: 7:00 am - 4:00 pm Pacific Time, Monday - Friday

Mailing address:
PO Box 1910
Port Townsend, WA 98368 USA

Click here for an index to this and previous COWs