(3) Require, by subpoena or otherwise, the production of evidence and witnesses;
(4) Enter any property where an accident subject to the NTSB's jurisdiction has occurred, or wreckage from any such accident is located, and take all actions necessary to conduct a complete investigation of the accident;
(5) Inspect, photograph, or copy any records or information (including medical records pursuant to paragraph (b)(2) of this section), and correspondence regardless of the date of their creation or modification, for the purpose of investigating an accident;
(6) Take possession of wreckage, records or other information if it determines such possession is necessary for an investigation; and
(7) Question any person having knowledge relevant to a transportation accident.
[1] https://www.law.cornell.edu/cfr/text/49/831.9
[2] https://www.govinfo.gov/content/pkg/USCODE-2021-title49/pdf/...