46 C.F.R. § 287.23
(a) Noncompliance. The amount of the gain which is that portion of the construction reserve fund otherwise constituting taxable income under the law applicable to the taxable year in which such gain was realized shall be included in the taxpayer's gross income for such taxable year for income or excess-profits tax purposes, if:
(1) A portion of such fund is withdrawn for purposes other than—
(2) The taxpayer fails to comply with the requirements of section 511 of the Act or the regulations in this part relating to the utilization of construction reserve funds in the construction, reconstruction, reconditioning, or acquisition of a new vessel, or the liquidation of purchase-money indebtedness on such a vessel.
If securities on deposit in a construction reserve fund are sold and the amount placed in the fund in lieu thereof is less than the value of the securities at the time of their deposit, the difference between such market value and the amount placed in the fund in lieu of the securities will be deemed to have been withdrawn. With respect to the substitution of new financing in the case of an irrevocable commitment, see paragraph (d) of § 287.13.