4. Usage of TOPOFLIGHT universal protocol

When the airplane approaches a flight line, the system is in the NOT_LOGGING state. A user-defined time before the airplane reaches the start of the flight line, "StartLogging" will be sent from TOPOFLIGHT to the TOPOFLIGHT universal protocol. After a user-defined duration following the airplane’s passage past the end of the flight line, "StopLogging" will be sent from TOPOFLIGHT to the TOPOFLIGHT universal protocol.

During the flight over the line, no additional information will be sent from TOPOFLIGHT to the TOPOFLIGHT universal protocol. Only "StartLogging" will be sent at the beginning and "StopLogging" at the end of the line. Image capture and other data collection triggers will be managed internally by the TOPOFLIGHT universal protocol.

When the user disconnects from the TOPOFLIGHT universal protocol, the system must first be set to NOT_LOGGING, after which "SystemStop" can be called.