To provide a system to confirm a locked state of a device such as a galley arranged in a passenger compartment of an aircraft by radio.

A galley 200 disposed in a passenger compartment of an aircraft is equipped with a latch 230 that locks a door of the compartment 212 and a turn retainer 260 installed at an upper part of a space storing a service cart 250, and the latch 230 and the turn retainer 260 are equipped with the battery-less radio switch, and when the latch or the turn retainer is operated at a lock position, a radio signal W₁ is sent with detection of this operation. A PDA 280 that the cabin attendant CA has, displays this signal, and the cabin attendant CA confirms a locked state of a device.