Which IFF mode is designated for military use only?

Mode 1 is specifically designated for military use only. This mode is part of the Identification Friend or Foe (IFF) system used by military aircraft to distinguish between friendly forces and potential threats. Mode 1 provides a two-digit code that aids in identification during various operational scenarios.

This IFF mode is critical in ensuring operational security and situational awareness on the battlefield, allowing military personnel to communicate their identity effectively without revealing sensitive information that could be intercepted by adversaries. The codes transmitted in Mode 1 are intended for military purposes and are not utilized in civilian air traffic control.

In contrast, the other modes serve different functions or are designed for broader use. For instance, Mode 2 is also reserved for military use but is used for specific identification purposes, while Mode 3/A is primarily for civilian operations. Mode 5 is an advanced mode that includes encryption and is designed to provide enhanced security and interoperability for forces; however, it is not limited to military use. Each mode serves a unique purpose within the IFF framework, but Mode 1's specific categorization as a military-only designation underscores its role in maintaining operational integrity among armed forces.