[oldcomputerguy]

I find it hard to believe that engines are designed to break off. The lone exception being some horrendous forces that would make it the last resort.

Having worked on planes in the USAF, this is the first time I have heard that mentioned.

[billorites]

I find it hard to believe that engines are designed to break off.

The engines are very heavy and massive. The pylons which connect them to the wings are designed to be the weak link to protect the wing. They are strong as regards fore and aft loads, but are designed to fail when a rolling moment (horizontal) is applied.