Why a small trolley makes a big cabin noise
An aircraft cabin is a long, enclosed space lined with hard surfaces. Sound from a catering trolley—wheels rolling over floor joints, a latch clicking, a drawer closing—can bounce off those surfaces instead of fading quickly. The trolley also travels close to seated passengers, so even an ordinary clatter may be hard to ignore when the cabin is otherwise quiet.
Sleep makes the contrast sharper
When you are drifting off, you are less engaged with your surroundings, but your brain still monitors sudden changes in sound. A steady background hum can become easy to tune out; a new rattle or clunk stands out against it and may pull you back toward wakefulness. If the cart passes nearby, the sound grows and then recedes, giving your attention another reason to follow it.
The service itself has to move down the aisle, where space is tight and passengers are seated close together. That leaves little room to route the trolley far from people trying to rest. The interruption is not necessarily loud in an absolute sense; its timing, contrast, and proximity do much of the work.
