Calculation of safe speed and minimally admissible distance of closing of ships during radar information usage

Grygorii Kalinichenko, Yevgeniy Kalinichenko


Exceeding the safe speed and the minimum allowable distance when ships approach each other is considered as one of the main reasons for their collision, especially when using radar information when sailing in reduced visibility or in confined areas. When assigning a safe speed, among other factors, the rules recommend to take into account the state of visibility of the maneuverable capabilities of the ship, especially the distance required to completely stop the ship, as well as the characteristics, efficiency and limitations of radar equipment. But, besides the quality recommendations in the COLREGs, there are no quantitative estimates of the safe speed and excessive convergence of the ships. Each navigator subjectively assigns a safe speed and determines the minimum allowable approach distance for ships. Therefore, the development of a universal method for calculating safe speed and the minimum allowable distance when using radar information is relevant, and the method itself is effective when used on ships, especially when sailing in difficult navigation areas and with limited visibility. The developed method allows to automate the choice of safe speed and eliminate the subjective factor when it is appointed navigator


navigation safety; international regulations for preventing collisions at sea (COLREGs); maneuvering of ships

Full Text:



Transportation Safety Board of Canada. Statistical Summary: Marine Occurrences (2017). Canada.

Cockcroft, A., Lameijer, J. (2012). A Guide to the Collision Avoidance Rules. Butterworth-Heinemann, 200. doi:

Scripture, F. R. (1966). Marine Radar Collision Avoidance System Re-quirements. Navigation, 13 (4), 295–301. doi:

Vahushchenko, L. L., Vahushchenko, A. L. (2010). Podderzhka reshenyi po raskhozhdenyiu s sudamy. Odessa: Fenyks, 108–110.

Vahushchenko, L. L. (2000). Sudno kak ob'ekt avtomatycheskoho upravlenyia. Odessa: OHMA, 140.

Maltsev, A. S. (2002). Manevryrovanye sudov pry raskhozhdenyy. Odessa: Morskoi trenazhernyi tsentr, 66–79.

Rodyonov, A. Y. (1966). Avtomatyzatsyia sudovozhdenyia. Moscow: «Transport».

Yarkyn, P. Y., Kalynychenko, E. V. (2003). Opredelenye kharakterystyk aktyvnoho tormozhenyia sudna. Alternatyvnyi podkhod. Sudovozhdenye, 6, 158–165.

Yarkyn, P. Y., Maltsev, A. S., Kalynychenko, E. V. (2004). Opredelenye kharakterystyk razghona i podtormazhyvanyia sudna. Alternatyvnyi podkhod. Visnyk ONMU, 13, 63–71.

Demyn, S. Y. (1975). Tormozhenye sudna. Moscow: Transport, 81.



  • There are currently no refbacks.

Copyright (c) 2018 Grygorii Kalinichenko, Yevgeniy Kalinichenko

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

ISSN 2585-6847 (Online), ISSN 2585-6839 (Print)