Final answer:
When radar contact is lost and an aircraft has not yet started the final approach, the standard action is to execute a missed approach. This protocol ensures safety and allows the pilot to try landing again or divert to an alternate airport if necessary.
Step-by-step explanation:
If radar contact is lost during an approach and the aircraft has not started final approach, the correct procedure for the pilot in command and as directed by Air Traffic Control (ATC) would usually be to execute a missed approach. This procedure is designed to ensure the safety of the aircraft and any nearby traffic by providing a predefined path that the aircraft can follow to avoid obstacles and reestablish communication with ATC. Depending on the specific circumstances and the procedures of the particular airport or airspace, different instructions might be provided, but executing a missed approach is a common protocol that allows for a safe resolution to the situation.
Executing a missed approach also prepares the aircraft for another attempt at landing or to divert to an alternate airport if conditions do not improve. These procedures are outlined in the pilot's operating handbook and by the regulations governing the airspace in which the aircraft is operating.