What is the condition under which a CSD unit can be reconnected after disconnection during flight?

A CSD (Constant Speed Drive) unit can only be reconnected on the ground by maintenance personnel following a disconnection during flight because it requires professionals to perform the necessary checks and balances to ensure the system's safety and integrity. Reconnecting a CSD unit involves addressing technical aspects that could affect engine performance and the overall operational safety of the aircraft.

Maintenance personnel have the expertise to assess the situation carefully, confirm that all necessary protocols and safety measures are in place, and ensure that any underlying issues that caused the disconnection are resolved. This helps prevent potential hazards that might arise if untrained personnel or unapproved methods were employed to reconnect the unit prematurely or inappropriately. Therefore, this option emphasizes the necessity of specialized knowledge and adherence to safety standards before any reconnection can be made after disconnection during flight.