FAR 91.403(a) requires that an AD compliance record be kept. Some AD are one-time and others recurring. They notify aircraft owners and others of unsafe conditions and what must be done to operate the aircraft. ADs may be an emergency, which requires immediate compliance or less urgent nature with some time slack allowed. ADs are FAR’s and must be complied with unless exempted. There is no ‘overfly allowance as may exist with inspections. FAR 91.417 requires a record be maintained showing status of all ADs applicable to an aircraft. This often is on a separate sheet.