What action is required if the pitot tube is intact but the static port is blocked?

When the static port becomes blocked while the pitot tube remains intact, the aircraft’s altimeter, vertical speed indicator, and airspeed indicator can provide incorrect readings, potentially compromising the safety and control of the aircraft.

Utilizing an alternate static source is necessary because it allows the pilot to access a different measurement of static pressure, which is crucial for accurate readings of altitude and vertical speed. This procedure mitigates the risk of flying with misleading instrument indications that could arise from the blockage of the primary static port.

The other choices do not address the limitations created by a blocked static port. Continuing flight normally could lead to dangerous situations since the instruments relying on static pressure would be unreliable. Landing as soon as possible is not always practical unless significant issues arise based on instrument readings. Adjusting the flight path may not provide enough resolution as it doesn't rectify the instrument issues caused by the blocked static port either. Therefore, using an alternate static source is the appropriate and effective response to ensure the aircraft can be safely operated.