14 CFR 49.33: Eligibility for recording: general requirements.

A conveyance is eligible for recording under this subpart only if, in addition to the requirements of §§ 49.11, 49.13, and 49.17, the following requirements are met:

(a) It is in a form prescribed by, or acceptable to, the Administrator for that kind of conveyance;

(b) It describes the aircraft by make and model, manufacturer's serial number, and United States registration number, or other detail that makes identification possible;

(c) It is a true copy of an original document, certified under § 49.21, or an original document or a duplicate original document;

(d) It affects aircraft registered under 49 U.S.C. 44101-44104; and

(e) It is accompanied by the recording fee required by § 49.15, but there is no fee for recording a conveyance named in § 49.31(b).