Which is a listed ECS subsystem?

• A. Air Cycle conditioning
• B. OBOGS
• C. Canopy Seal
• D. Fuel pump control

Answer: (C)

Understanding what counts as an ECS subsystem helps you see why the canopy seal fits. The Environmental Control System encompasses the parts that condition and manage the cockpit environment—temperature, air supply, pressure, and the integrity of the conditioned air boundary. The canopy seal is included because it defines the boundary of the conditioned cockpit air; when the canopy is properly sealed, the ECS can maintain correct cabin pressure and temperature without leaks, easing the load on the air conditioning and air cycle components and ensuring a stable environment for the crew.

The other options fall outside that boundary in this context. Air Cycle conditioning is a direct ECS function, responsible for cooling and heating the cockpit air. OBOGS provides breathable oxygen and is generally categorized under life support rather than ECS. Fuel pump control relates to the fuel system and does not participate in environmental conditioning or cockpit pressurization.

So, canopy seal is the listed ECS subsystem because it directly supports the integrity and efficiency of the environmental control around the crew.