This document amends the Customs Regulations concerning the duty-free entry of civil aircraft merchandise to reflect amendments to General Note 6 of the Harmonized Tariff Schedule of the United States made by the Miscellaneous Trade and Technical Corrections Act of 1996. The amendments allow an importer to claim duty-free admission of civil aircraft merchandise without submitting a certificate, or having one on file at Customs, at the time of entry. The amendments also allow an importer to make a post-entry claim for duty-free admission by filing a statement prior to liquidation of the entry or before the liquidation becomes final.