Pacific Air Flight 121

...that would have been the title of what is now called Snakes On a Plane, if Samuel Jackson (and likely others) hadn't convinced the producers to change the title back to its original title, rather than their changed, bland title.

Jackson in the March Premiere Magazine: "I'm saying, 'So are you seriously going to leave this name like this?' And they're going, 'Yeah, we don't want to give too much away to the audience.' I'm like, 'Yeah, you do. That's the way you get them in here. Nobody wants to see Pacific Air Flight 121. People want to see Snakes on a Plane.  ... Before I opened the first page [of the script], Snakes on a Plane. If this is what I think it is, I want to be in this. I want to be on a plane full of poisonous snakes."

Sometimes the suits just overthink things.