See. But building a jet engine that "just works" without a particular profitability is not at all hard. Like, one that burns 50% fuel for same thrust than the b

See. But building a jet engine that "just works" without a particular profitability is not at all hard. Like, one that burns 50% fuel for same thrust than the best state of the art. That's about the level of disposable engines used in cruise missiles and drones.