Article 13.05(2)(a) - Steerageway under vessel’s own power
There are vessels that can — when using the bow thruster — just attain the required speed of 6.5 km/h during headway operation, but not when going astern. Vessels whose maximum length exceeds 86 m are required to meet the requirements of articles 5.07 and 5.08, since they do not have sufficient turning capacity on narrow stretches of river. This gives rise to the problem that these vessels are unable to stop or bring the vessel to a standstill using the bow thruster facing downstream.
Must a minimum speed of 6.5 km/h when going astern also be attained by these vessels? How do other inspection bodies handle this problem?
ESI-II-11 defines the requirements for Steerageway under vessel’s own power conclusively and does not contain any provisions concerning the stopping capacity; it is therefore not possible to require vessels to be able to stop or bring the vessel to a standstill using only the bow thruster when navigating downstream. It is also not necessary to be able to demonstrate a minimum speed when going astern. The checking called for in the Administrative Instruction only refers to the turning motion.
RV/G (12) 16 rev. 1 = JWG (12) 14 rev. 1; RV/G (12)m 59 = JWG (12)m 61, D8; JWG (12)m 91, item 7.2
Joint working group JWG, bow thruster