(a) Aircraft departing from the U.S. One copy of the air cargo manifest shall be used as a clearance certificate when endorsed by the port director to show that clearance is granted.

(b) Scheduled aircraft. If a scheduled aircraft clears at an airport which is not the airport at or nearest the place of final take-off from the U.S., two copies of the air cargo manifest shall be filed. One copy shall be used as a clearance certificate when endorsed by the director of the port where clearance is obtained, and the second copy shall be attached to the first for use at subsequent U.S. ports.