In the event of a clogged static port in a constant speed climb, how will the VSI behave?

In a scenario where a static port becomes clogged during a constant speed climb, the behavior of the vertical speed indicator (VSI) is important to understand. The VSI operates by measuring changes in static air pressure which corresponds to changes in altitude. If the static port is clogged, the VSI will lack the necessary input to accurately gauge the change in altitude.

In a constant speed climb, the aircraft is actually ascending, which ordinarily would cause the VSI to show an upward trend. However, with a clogged static port, the instrument has no reference to detect the ongoing climb. Therefore, the VSI will read as zero, indicating that there appears to be no vertical speed. This is because the sensor inside the VSI requires a pressure differential that it cannot detect when the static port is obstructed, leading to a false indication of level flight despite the aircraft continuing to climb.

This behavior highlights the crucial reliance on static pressure for vertical speed measurements and illustrates the potential impact of instrument errors due to external blockages.