For my work I travel all over the world a few times a year, mostly sub-Saharan Africa. Let's just say that that has lead to a few "I will never fly again!" moments.
Two in particular jump out.
The plane was circling Cotonou, Benin's air port, at night. The city is right on the oncean, as is the airport. This was my first time to Africa too. The plane makes a steep landing, feeling like it is about to crash in to the ocean. As the plane is landing the French pop music I was listening to on the plane's various Air France music stations kept singing "When planes come crashing down!" or something that sounded like that, and the overhead map stopped on 666km. So those two combinations had me praying and freaking out as the plane did a hard landing.
Was flying Ethiopian Air from Ethiopia to DC, that is about a 14 hour flight (and this was after an 8 hour flight from elsewhere in Africa to Ethiopia). The flight turned in to an 18 hour flight, and half the bathrooms stopped working on the plane, and my TV gave out while on a quick re-fuel in Dublin, Ireland. And that airlines doesn't allow the use of tablets, phones, or lap tops. So for several hours I was just trying to read, sleep, and twiddling my thumbs, or waiting 30+ minutes to use the bathroom. Not pleasant.