What is the secondary surveillance radar code for radio failure or lost communications?

The secondary surveillance radar code for radio failure or lost communications is 7600. This specific code is used in aviation to indicate to air traffic control that an aircraft has experienced a communication failure with ATC, which may impair its ability to receive instructions or information from controllers. When an aircraft squawks 7600, it alerts radar and ground stations that there is an issue with communication, allowing for appropriate responses and safety measures to be enacted.

Understanding the context of the other codes can further clarify the significance of 7600. For example, 7500 is designated for unlawful interference, often associated with hijacking scenarios, and 7700 indicates a general emergency. The code 2200 does not have a recognized significance in this aspect; thus, it is not relevant to the context of lost communications.

Correctly identifying these codes is crucial for aviation safety and ensures that communication issues can be quickly addressed by air traffic control and other entities involved in flight operations.