New ship means a ship -
(1) For which the building contract is placed after December 31, 1975; or
(2) In the absence of a building contract, the keel of which is laid or which is at a similar stage of construction after June 30, 1976; or
(3) The delivery of which is after December 31, 1979; or
(4) That has undergone a major conversion -
(i) For which the contract is placed after December 31, 1975;
(ii) In the absence of a contract, the construction work of which is begun after June 30, 1976; or
(iii) That is completed after December 31, 1979.
(5) For the purposes of §§ 151.26 through 151.28, which is delivered on or after April 4, 1993.