The HSD-400 in BLOCK 6 aircraft is replaced by three components. They are what?

• A. Cobham Aviator 700 Satellite Data Unit (SDU), Swift Broadband unit, and High Power Amplifier
• B. Cobham Aviator 700 SDU, DF-500, and EGI 3
• C. Swift Broadband unit, HSD-600, and Antenna
• D. Aquila 500 SDU, Swift BroadBand unit, and Medium Power Amplifier

Answer: (A)

In this replacement, the HSD-400 is replaced by a modular SATCOM setup that splits the functions into three specialized components. The Cobham Aviator 700 Satellite Data Unit handles the satellite data link and protocol processing between the aircraft and the satellite network, acting as the interface and controller for the data path. The Swift Broadband unit provides the actual broadband payload, enabling high-speed data and voice services over the satellite and integrating with the aircraft’s network. The High Power Amplifier supplies the necessary RF power to boost signals for uplink (and support the downlink as part of the system’s gain chain), ensuring reliable communication with the satellite.

This combination reflects a move from a single integrated unit to a triad of modules that together deliver the same SATCOM capability with greater flexibility and performance. Other options mix in components that aren’t part of this Block 6 replacement pattern, such as different SDUs, other amplifiers, or unrelated subsystems, which don’t align with the specified configuration.