Which operations require keyed PPS receivers according to CNAF M-3710.7?

• A. Civil airspace navigation operations only
• B. Combat, combat support, and combat service support operations
• C. Training flights
• D. Research flights

Answer: (B)

Keyed PPS receivers are used to authenticate GPS signals, giving trusted position data in environments where the GPS signal might be contested or spoofed. CNAF M-3710.7 specifies that this level of protection is required for missions where navigation integrity is critical due to potential enemy interference. Combat, combat support, and combat service support operations fall into that category, since they can occur in hostile or denied environments and rely on accurate, protected navigation to complete the mission safely. Civil airspace navigation, training flights, and research flights are typically conducted in lower-threat settings and do not mandate keyed PPS receivers, so they are not required to use this secure navigation capability.