With which type of pressurization system does the pressure difference increase with altitude?

The correct answer is constant cabin pressure. In a constant cabin pressure system, the cabin is maintained at a predetermined atmospheric pressure despite changes in external pressure as the aircraft climbs in altitude. This is achieved by actively controlling and adjusting the cabin pressure to remain stable, which leads to an increase in the pressure differential between the cabin and the outside atmosphere as altitude increases.

In essence, while the aircraft climbs, the ambient pressure decreases, but the cabin pressure remains constant. This design ensures that passengers and crew experience a more comfortable environment, minimizing issues such as hypoxia, discomfort, or potential physiological problems that could arise from rapid changes in altitude and pressure.

In comparison, other pressurization systems may not maintain this constant pressure and could allow for variations in cabin pressure relative to altitude changes, which could lead to different passenger experiences during ascent and descent. A variable pressure system, for instance, may adjust and vary cabin pressure based on different flight phases, leading to less predictability in pressure changes.

The uniquely controlled environment of a constant cabin pressure system makes it preferable for long-duration flights, ensuring consistent safety and comfort levels throughout different flight conditions.