Liberators, especially when heavily laden with fuel and bombs, had a tendancy for the fuselage to fracture at a point just in front of the mainplane, at the upper turret aperture, usually triggered by nose undercarriage problems or running into soft ground. It often only resulted in a fractured fuselage but sometimes depending on speed, weight and nature of the surface the whole front fuselage could be crushed, as in the picture.
I have seen photo,s of trials by Consolidated to come up with a fix which meant simulating the failure by pulling on the fuselage with cables but I think nothing was done to resolve it.
This was one major benefit the B17, with its low wing and exposed main whhels, had over the B24, which was also very bad in a belly landing when the fuselage again would collapse under the weight of the wing. And to top it all it didnt behave well in a ditching, depite its flying boat hull appearance.
I have always loved the Liberator in preference to the B17 but its easy to have that view now, I bet the people who flew them in anger had other thoughts. Very brave men.