Thanks for finding this. The enormous size of the document itself speaks volumes.
It looks like the "stale" period requires the FAA to notify a suspected violator within 6 months of the violation. There are exceptions for more serious things that could result in revocation of certificates based on lack of qualifications, or fines over $50k. On the plus side, the ASRS report remains an immediate "get out of jail" card for unintentional violations. Pretty important in this era of the perpetual pop-up TFR threat.
Section 5 explains the shorthand that's in Table 4.1:
5. Time Limitations in Cases Involving Certificate Suspensions or Revocations. Cases involving the suspension or revocation of airman, type, production, airworthiness, air carrier operating, airport operating, air agency and air navigation facility certificates are reviewed by the NTSB. Section 821.33 of the NTSB’s Rules of Practice in Air Safety Proceedings (49 C.F.R. part 821), known as the stale complaint rule, provides that an FAA complaint (order) may generally be dismissed if the offenses alleged occurred more than six months prior to the Administrator’s advising a respondent of the reasons for the proposed action. Advising the respondent refers to the respondent’s receipt of the legal document sent by FAA legal counsel proposing the certificate action.
a. Exceptions to Stale Complaint Rule.
(1) The first exception involves cases in which the FAA’s complaint alleges the certificate holder lacks qualifications to hold the certificate (for example, revocation cases). In these cases, the 6-month rule does not apply. The FAA does not use revocation as a means to avoid dismissal of charges under the stale complaint rule. Although the 6-month stale complaint rule does not apply to qualifications cases, the FAA expedites such cases because they generally involve significant safety issues.
(2) The second exception to the 6-month stale complaint rule involves cases in which the FAA can show that it had good cause for not meeting the 6-month deadline. The most common good cause circumstance is found in late-discovery cases, in which the FAA discovers the violation after the date of violation. In these cases, however, the FAA does not have an extra six months from the date of late discovery to issue its notice. Rather, the FAA must put its investigation of these cases on a fast track, and must document priority handling at all stages of the investigation and review. Contemporaneously created documents and notes tracking what the investigating office did during the investigation are persuasive in showing that the FAA gave a case priority handling.
(3) The third exception to dismissal under the stale complaint rule is when the imposition of a sanction is in the public interest despite the delay. This situation is rarely, if ever, found by the NTSB.
b. Definitions.
(1) Date of violation. The date the respondent violated the regulation. This date starts the 6-month stale complaint period.
(2) Date known to FAA. The date the FAA knew or reasonably should have known of the likelihood of a violation. This date is not the date FAA investigating personnel determined there was a violation; rather, it is the date preliminary information was received that triggered or should have triggered an investigation.
(3) Priority handling. Priority handling means the FAA investigative office must process this case before all other non-emergency matters. This may mean that cases must be reassigned within an office, because, generally, it is not diligent handling if case processing is delayed because an employee is in training or on leave.
c. Examples.
(1) An FAA air traffic controller observes a violation on January 1. FAA investigative personnel receive the pilot deviation report on May 1. This case goes stale on July 1. FAA investigative personnel and FAA legal counsel must process this case with priority handling so the alleged violator receives the notice before July 1.
(2) A mechanic performs poor maintenance on February 1 but the violation is not discovered until July 15 following an accident. The case goes stale on August 1. However, the investigation is complex and cannot be finished before August 1. Therefore, the investigation must be given priority handling so that the agency can show good cause for the delay.
(3) A mechanic performs a 100-hour inspection and approves the aircraft for return to service on January 1. The following January, another mechanic inspects the aircraft and the
owner reports to the FAA that an airworthiness directive was due and not complied with at the time of the previous inspection. The FAA could go forward with a notice of proposed certificate action only if the investigative office can document that it processed the case expeditiously as a priority matter.
(4) A mechanic commits a maintenance violation on January 1. An FAA inspector discovers the violation on April 1 and starts an investigation. On May 30, the inspector goes to Oklahoma City, Oklahoma for six weeks of training. During his or her absence, the office does not reassign the case and does not do any work to further the investigation. On the inspector’s return to the office in mid-July, the case is stale and the case cannot go forward because the office cannot show priority handling.
There's a lot more about fines, investigations etc. etc. but this appears to be the part that's most relevant to part 91 pilots.
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