Which procedure should you follow if the second fuel sample is also bad?

If the second fuel sample is also bad, notifying Maintenance Control is the appropriate procedure to follow. This action ensures that the situation is documented and that the appropriate personnel can respond to the potential issue with the fuel. Maintenance Control has the expertise and authority to direct further actions, such as conducting a more detailed investigation into the fuel quality problem or implementing procedures to resolve the issue.

Continuing operations without addressing the bad fuel sample could jeopardize the aircraft's safety and performance. Taking a third sample might not yield different results and only delays proper action, while replacing the fuel tank is typically not a standard or immediate response to a fuel quality issue without a thorough assessment by trained personnel. Therefore, notifying Maintenance Control is crucial for ensuring safety and compliance with operational standards.