U.S. flag An official website of the United States government.
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

i

Stability III: Heeling, Righting Moments



Details

  • Personal Author:
    Backus A
  • Description:
    In the last installment of the ongoing series on stability 9CFN September 2003, page 13B), we explored the relationship between the center of gravity and the center of buoyancy. This time, let's look at the relationship between the force of heeling and righting as we continue our effort to better understand how to avoid instability that can lead to capsize. Last time, we saw that the center of gravity shifts as the load shifts while the center of buoyancy shifts based on both the load shift and how much of the vessel is underwater. The center of buoyancy is the point through which the buoyant force seems to be pushing up. Now, let's think about these additional factors. The force that encourages the boat to heel or tip is called the "heeling moment." In a sailboat, this heeling is caused mainly by wind and waves. In a fishing boat, heeling is caused by wind, waves, and the distribution of the load. The force produced by buoyancy that encourages the boat to right itself is called the "righting moment." When the righting moment counteracts the heeling moment, the boat is sable. The "righting arm" is the term given to the distance between vertical lines drawn through the center of gravity and the center of buoyancy respectively. A positive righting arm exists as the center of buoyancy moves from directly under the center of gravity toward the heeling side of the vessel. In fact, as long as the righting moment is equal to or greater than the heeling moment, the boat will not capsize. [Description provided by NIOSH]
  • Subjects:
  • Keywords:
  • ISSN:
    0273-6713
  • Document Type:
    Text
  • Funding:
    Grant
  • Genre:
    Journal Article
  • Place as Subject:
  • CIO:
    National Institute for Occupational Safety and Health (NIOSH)
  • Topic:
    Workplace Safety & Health
  • Location:
    North America
  • NIOSHTIC Number:
    nn:20061914
  • Citation:
    Commercial Fish News 2003 Oct; :22A
  • Contact Point Address:
    Ann Backus, MS, Director of Outreach, Department of Environmental Health, Harvard School of Public Health, Boston MA
  • Email:
    abackus@hohp.harvard.edu
  • Federal Fiscal Year:
    2004
  • Performing Organization:
    Harvard School of Public Health
  • Peer Reviewed:
    False
  • Start Date:
    20030701
  • Source Full Name:
    Commercial Fisheries News
  • End Date:
    20050630
  • Collection(s):
  • Main Document Checksum:
    urn:sha-512:7f0507583908b0bfe7be92aea538b3bf349d11b9c253a5b50361c0ff87b9e76fa4497a31853f6cbcac05e6185bb71b325c5bdb94ae6944154417add5a66999b6
  • Download URL:
  • File Type:
    Filetype[PDF - 242.69 KB ]
PREVIOUS
ON THIS PAGE
Details
CDC STACKS serves as an archival repository of CDC-published products including scientific findings, journal articles, guidelines, recommendations, or other public health information authored or co-authored by CDC or funded partners.

As a repository, CDC STACKS retains documents in their original published format to ensure public access to scientific information.
BACK TO TOP