Which statement about the ASI mechanism is true when facing a blocked pitot tube?

Which statement about the ASI mechanism is true when facing a blocked pitot tube?

• A. The ASI will provide a reading of maximum speed
• B. The ASI will show an inaccurate speed
• C. The ASI will indicate zero airspeed
• D. The ASI will function normally in this condition

Answer: (C)

When a pitot tube is blocked, it prevents the measurement of dynamic air pressure, which is crucial for determining airspeed. The Airspeed Indicator (ASI) relies on the difference between the static air pressure and the dynamic air pressure measured by the pitot tube to give an accurate airspeed reading. In the event of a blocked pitot tube, the ASI will not receive the necessary pressure information and will typically reflect a static pressure condition. Under these circumstances, the ASI often indicates zero airspeed. This is because, without dynamic pressure input, the ASI cannot calculate a valid airspeed value, leading it to default or indicate a zero speed reading. Hence, the statement that the ASI will indicate zero airspeed is true in the context of a blocked pitot tube.

When a pitot tube is blocked, it prevents the measurement of dynamic air pressure, which is crucial for determining airspeed. The Airspeed Indicator (ASI) relies on the difference between the static air pressure and the dynamic air pressure measured by the pitot tube to give an accurate airspeed reading.

In the event of a blocked pitot tube, the ASI will not receive the necessary pressure information and will typically reflect a static pressure condition. Under these circumstances, the ASI often indicates zero airspeed. This is because, without dynamic pressure input, the ASI cannot calculate a valid airspeed value, leading it to default or indicate a zero speed reading. Hence, the statement that the ASI will indicate zero airspeed is true in the context of a blocked pitot tube.