[WalterBright]

There's an enormous amount of energy in a jet engine with that spinning turbine. Then there's all the heat, fuel, and fire in it. When that energy lets go, you don't want to be anywhere near it.

It's amazing that jet engines work at all! Yet the safety record of the engines is incredibly good.

[dotancohen]

But twins typically have even larger turbines, no?

[WalterBright]

High bypass fans are newer engine designs, nothing to do with being used in twins.

Though in general, a new engine design necessitates a new wing design, which means a new airplane.