AC 33.4-1 - Instructions for Continued Airworthiness

"airworthiness", and is consistent with the test applied to the initial issuance of an aircraft’s standard airworthiness certificate, and in the context of adjudication of the question of aircraft airworthiness. Therefore, for the purpose of this AC, an aircraft engine is considered "airworthy" when the following two conditions are met:

  Standards, Instructions, Airworthiness, Continued, Instructions for continued airworthiness, Standard airworthiness