Theme of Flight 29 Down

So far, after three chapters that i have read of Flight 29 Down, the theme has been, expect the unexpected,because all the kids were having fun on the plane and messing around. Not thinking anything could happen but then the engine blew out and all the kids were freaking out. "But now that Nathan was looking out the window at the two burning engines as they flew somewhere over the endless ocean" (Machale/ Rogow 16).