Total air pressure is gradually released due to partial blockage of the pitot tube. What will be the effect on airspeed indication?

When total air pressure is gradually released due to a partial blockage of the pitot tube, the airspeed indication will indeed start decreasing. The pitot tube measures the dynamic pressure of the air, which is necessary for accurate airspeed readings.

As the blockage occurs, the pressure within the tube begins to drop, resulting in a decrease in the dynamic pressure measurement. The airspeed indicator is designed to show speed based on the difference between static and total pressure; therefore, with the total pressure compromised, the instrument will represent a lower airspeed.

This situation does not result in an accurate true airspeed reading, nor does it indicate a climb or remain constant. The indicator is not capable of compensating for the partial blockage, leading to a misleadingly lower airspeed display as compared to actual conditions.