Just what you don’t want to see out of your plane window!

[durhamplumber]

It's none of those, but the flying bits of fan blades that could penetrate the cabin.

Indeed....Uncontained is much nastier... pieces of high velocity alloy in the cabin are a bit alarming!

 

[crystal ball]

Surely it's taking off and landing?

Falling down the escalator after the pre flight stiffeners

 

[securespark]

Exactly, taking off and landing!