Abstract: Each flight attendant would carry a small portable receiver/transmitter device, similar in size to a pager, and a central receiver/transmitter located in the cockpit. Each portable receiver/transmitter has a numerical designation (1, 2, 3, etc.) which is unique to that one device. The portable receiver/transmitter has two buttons (yellow alert and red alert), a numerical display, indicator lights, and a vibrator. In a developing situation, a nearby flight attendant presses either the yellow or red alert button (depending on the severity of the situation), producing a radio frequency (RF) signal. The central receiver/transmitter receives, processes, and re-broadcasts the signal to all other portable receiver/transmitters worn by flight attendants. The portable receiver/transmitters vibrate to alert the wearers to the situation. A light (either red or yellow) illuminates on all portable receiver/transmitters, and the numerical designation of the sending receiver/transmitter appears on the displays.

Abstract: Each flight attendant would carry a small portable receiver/transmitter device, similar in size to a pager, and a central receiver/transmitter located in the cockpit. Each portable receiver/transmitter has a numerical designation (1, 2, 3, etc.) which is unique to that one device. The portable receiver/transmitter has two buttons (yellow alert and red alert), a numerical display, indicator lights, and a vibrator. In a developing situation, a nearby flight attendant presses either the yellow or red alert button (depending on the severity of the situation), producing a radio frequency (RF) signal. The central receiver/transmitter receives, processes, and re-broadcasts the signal to all other portable receiver/transmitters worn by flight attendants. The portable receiver/transmitters vibrate to alert the wearers to the situation. A light (either red or yellow) illuminates on all portable receiver/transmitters, and the numerical designation of the sending receiver/transmitter appears on the displays.