Why is it crucial for pilots to plan their approaches carefully when behind a heavier aircraft?

Planning approaches carefully when flying behind a heavier aircraft is crucial primarily to prevent wake turbulence encounters. Heavier aircraft generate significant wake turbulence as they pass through the air, which can be hazardous for smaller or lighter aircraft following too closely.

Wake turbulence occurs due to the swirling air left behind by a vortex from the wingtips of larger airplanes, and this phenomenon can create dangerous conditions for pilots who are not adequately prepared. By allowing sufficient spacing during approaches, pilots can minimize the risk of encountering this turbulence, which could lead to loss of control or other dangerous situations, especially during critical phases of flight such as landing or takeoff.

This understanding emphasizes the importance of maintaining safe distances and being aware of the size and type of aircraft ahead, particularly in environments like busy airports where mixings of various aircraft sizes are common.