Abstract
The article specified in aviation legislation, 'The captain has the final authority and responsibility in flight safety' could be one reason running counter to applying "Vertrauensgrundsatz". In practice, however, captains do not have professional skills in every task and they should distribute duties and responsibilities to flight attendents and other staffs to operate the flight as safely and efficiently as possible. Therefore, in aviation, fair criterion, namely, "Vertrauensgrundsatz" is necessary to balance between efficiency and legal interest for participants. In addition, when it comes to mutual trust of duty which was the starting point of this study, the standard in mutual advice or interference must be based on the duty specified in air law and flight regulations. Also, pervasive trust will not only be attributed to joint responsibility but an act that cannot be trusted.