The newly compiled “Guidelines for Maneuverability Assessment of Azimuthing Propulsion Ships” (2026) by the China Classification Society will take effect on August 1.
In response to the roll stability safety issues that may arise during the maneuvering process of azimuthing propulsion ships, the China Classification Society has conducted relevant research, identified key influencing factors, and, in conjunction with the development progress of relevant international rules by the IMO, compiled the “Guidelines for Maneuverability Assessment of Azimuthing Propulsion Ships” (2026). The guidelines are applicable to the assessment of maneuverability and roll stability during the maneuvering process of azimuthing propulsion ships. To facilitate implementation by the industry, the guidelines propose a graded assessment process for roll stability during maneuvering. The specific content includes 4 chapters and 1 appendix, with key points as follows:
Chapter 1 is General Requirements, specifying the scope of application of these guidelines, relevant definitions, declarations of conformity, and requirements for submitted drawings and documents.
Chapter 2 is Assessment Methods, clarifying methods such as single-degree-of-freedom roll motion assessment, 4-degree-of-freedom maneuvering motion assessment, full-time-domain CFD assessment, and self-propelled model basin test assessment.
Chapter 3 is Assessment Requirements, proposing requirements for the assessment process, assessment conditions, calculation verification, and maneuvering diagrams.
Chapter 4 is Reporting Requirements, proposing requirements for submitting assessment reports.
Appendix 1 is Assessment Cases, providing assessment examples using different assessment methods for a certain azimuthing propulsion tugboat.
