CNN CNN Newsroom With Brooke Baldwin November 10, 2015 19:51:00
Barometric pressure device, which simply put, it's like a balloon. as you go up in altitude, the balloon gets bigger. the balloon expands and makes contact at a certain altitude. that's one way to do it. those aren't used commonly anymore. those are about remote devices or controls or a phone that communicates to the device. so the other way to do this is the timer. timers aren't historically haven't been used often because it's hard to judge when the airplane is going to be at its most critical flight phase. so we have had bombs before they were detected because it went off either before or a...
Source: archive.org