14 CFR §243.7

1. (a)For covered flight segments, each covered airline shall:
   1. (1)Collect, or cause to be collected, the full name for each passenger who is a U.S. citizen. U.S.-citizen passengers for whom this information is not obtained shall not be boarded;
   2. (2)Solicit, or cause to be solicited, a name and telephone number of a contact from each passenger who is a U.S. citizen; and
   3. (3)Maintain a record of the information collected pursuant to this section.
2. (b)The covered airline operating the flight segment shall be responsible for ensuring compliance with paragraph (a) of this section.