The FAA Office of the Chief Counsel issues Legal Interpretations
in response to specific questions about how 14 CFR applies in a
given situation. They're authoritative agency reads of the
regulation — pilots, CFIs, and operators cite them to resolve
ambiguous compliance questions. Not preceedential like court
opinions, but binding on the agency.
14 CFR sections this interpretation addresses
Click into any section to see its current text. The interpretation's
PDF on drs.faa.gov has the full prose.