19 CFR § 191.76 - Landing certificate.
(a) Requirement. Prior to the liquidation of the drawback entry, Customs may require a landing certificate for every aircraft departing from the United States under its own power if drawback is claimed on the aircraft or a part thereof, except for the exportation of supplies under § 309 of the Act, as amended (19 U.S.C. 1309). The certificate shall show the exact time of landing in the foreign destination and describe the aircraft or parts subject to drawback in sufficient detail to enable Customs officers to identify them with the documentation of exportation.
(c) Signature. A landing certificate shall be signed by a revenue officer of the foreign country of the export's destination, unless the embassy of that country certifies in writing that there is no Customs administration in that country, in which case the landing certificate may be signed by the consignee or the carrier's agent at the place of unlading.
(d) Inability to produce landing certificates. A landing certificate shall be waived by the requiring Customs authority if the claimant demonstrates inability to obtain a certificate and offers other satisfactory evidence of export.