What is a typical power source for pneumatic systems on aircraft?

• A. Engine bleed air or dedicated air compressors; environmental control packs.
• B. Battery power
• C. Solar panels
• D. Hydraulic pumps

Answer: (A)

Pneumatic systems on aircraft get their air from a compressor source, not from electrical or hydraulic power. The typical supply is bleed air drawn from the engines (engine bleed air) or from a dedicated air compressor, which then feeds the environmental control packs. These packs condition the air—cooling, dehumidifying, and regulating pressure—before it goes to the cabin and other pneumatic subsystems. Using engine bleed air (or an APU/dedicated compressor when engines aren’t running) provides a steady, high-volume source of compressed air necessary for cabin pressurization and environmental control. Electrical power, solar panels, and hydraulic pumps support other systems, but they don’t serve as the primary source of the compressed air used by pneumatic systems.