Section 177.210 - Plans for sister vessels(a) Plans are not required for a vessel that is a sister vessel, provided:(1) Approved plans for the original vessel are on file at the Marine Safety Center or in the files of the cognizant OCMI;(2) The owner of the plans authorizes their use for the new construction of the sister vessel;(3) The regulations used for the original plan approval have not changed since the original approval; and(4) There are no major modifications to any of the systems to be used.(b) If approved plans for the original vessel are not on file at the MSC or with the cognizant OCMI, the vessel owner shall submit plans as described in § 177.202 of this part.