patricia aubrey is sitting in row 17. >> we took off, everything was normal. i always read a book when i'm flying. >> to fully understand what's about to happen to aloha flight 243, it's critical to know what an airplane goes through every time it flies. think of the plane's fuselage as a balloon. every time it goes up, the outside of the plane or the skin expands. that's from the cabin being pressurized so people can breathe at high altitudes where the air is thin. when the plane comes down, the skin contracts. every takeoff and landing, no matter how long or short the trip, is considered one cycle. and each cycle puts stress on an airplane, potentially causing microscopic cracks. >> so you have this constant pressure cycle where it expands, contracts, expands and contracts. over a period of time, the metal will eventually start to fatigue because of all of this expansion and contraction just like a balloon. >> as the 737 climbs to 24,000 feet, the cabin pressurizes and the skin on the plane expands, just as it's supposed to. but something else expands, too,