Which statement about LPAC's compressor type is true?

Which statement about LPAC's compressor type is true?

• A. It is a centrifugal compressor
• B. It is a piston compressor
• C. It is a rotary single screw compressor
• D. It is an axial flow compressor

Answer: (C)

The statement that LPAC's compressor is a rotary single screw is true. LPAC stands for low‑pressure air compressor, which needs a steady, continuous supply of air at relatively modest pressure and moderate volume for starting and pneumatic systems. A rotary screw compressor fits this duty well because it delivers a smooth, continuous flow with few pulsations and good efficiency in a compact package. This makes it reliable for constant operation aboard equipment that requires a steady air supply. In contrast, a centrifugal compressor is designed for very high flow and higher pressures and tends to be bulkier for that duty. A piston (reciprocating) compressor can produce pulsations and tends to be less favorable for continuous, smooth airflow in compact systems. An axial flow compressor is used for very high-speed, large-volume applications typical of jet engines, not for the low‑pressure, onboard LPAC role.

The statement that LPAC's compressor is a rotary single screw is true. LPAC stands for low‑pressure air compressor, which needs a steady, continuous supply of air at relatively modest pressure and moderate volume for starting and pneumatic systems. A rotary screw compressor fits this duty well because it delivers a smooth, continuous flow with few pulsations and good efficiency in a compact package. This makes it reliable for constant operation aboard equipment that requires a steady air supply.

In contrast, a centrifugal compressor is designed for very high flow and higher pressures and tends to be bulkier for that duty. A piston (reciprocating) compressor can produce pulsations and tends to be less favorable for continuous, smooth airflow in compact systems. An axial flow compressor is used for very high-speed, large-volume applications typical of jet engines, not for the low‑pressure, onboard LPAC role.