Which code is assigned for aircraft operating normally without any communication log?

The code assigned for aircraft operating normally without any communication log is 1200. This code is part of the VFR (Visual Flight Rules) squawk codes, which are used in the U.S. and indicate that the aircraft is flying in visual flight conditions and is not experiencing any emergencies or special circumstances requiring additional information.

When an aircraft operates under VFR, it is encouraged to operate with a transponder that transmits the 1200 code unless it is within controlled airspace or has been specifically assigned a different code by Air Traffic Control (ATC). Therefore, utilizing the code 1200 shows that the aircraft is in a normal state without any communication or operational issues.

In contrast, the other codes represent specific situations: 7700 indicates a general emergency, 7600 signifies a loss of communication, and 4000 does not correspond to standard codes commonly referenced in this context. Hence, 1200 is the appropriate code for normal VFR operations without any communication logs.