46 C.F.R. § 50.10-35
Constructed
The term constructed means the keel has been laid or, for vessels with no keel, assembly of at least 50 tons or 1% of the estimated mass of all structural material, whichever is less, has been completed.
The term constructed means the keel has been laid or, for vessels with no keel, assembly of at least 50 tons or 1% of the estimated mass of all structural material, whichever is less, has been completed.