14 CFR § 13.228 - Subpoenas.

(a) Request for subpoena. The administrative law judge, upon application by any party to the proceeding, may issue subpoenas requiring the attendance of witnesses or the production of documents or tangible things at a hearing or for the purpose of taking depositions, as permitted by law. A request for a subpoena must show its general relevance and reasonable scope. The party must serve the subpoena on the witness or the holder of the documents or tangible items as permitted by applicable statute. A request for a subpoena must be filed and served in accordance with §§ 13.210 and 13.211, respectively. Absent good cause shown, the filing and service must be completed as follows:

(1) Not later than 15 days before a scheduled deposition under the subpoena; or

(2) Not later than 30 days before a scheduled hearing where attendance at the hearing is sought.

(b) Motion to quash or modify the subpoena. A party, or any person upon whom a subpoena has been served, may file in the FAA Hearing Docket a motion to quash or modify the subpoena and must serve a copy on the administrative law judge and each party at or before the time specified in the subpoena for compliance. The movant must describe, in detail, the basis for the motion to quash or modify the subpoena including, but not limited to, a statement that the testimony, document, or tangible evidence is not relevant to the proceeding, that the subpoena is not reasonably tailored to the scope of the proceeding, or that the subpoena is unreasonable and oppressive. A motion to quash or modify the subpoena will stay the effect of the subpoena pending a decision by the administrative law judge on the motion.

(c) Enforcement of subpoena. Upon a showing that a person has failed or refused to comply with a subpoena, a party may apply to the appropriate U.S. district court to seek judicial enforcement of the subpoena.