To be honest, what you're describing really is, err, (I detest this term) "Rocket Science."
I'm going to part with Mr. Lewis's comments and say that while it does not require exceptional talent to be an Engineer, you will be rewarded with a learning experience like no other if you screw up. Can you be a mediocre engineer? Sure. Can you still maintain a career in this business in some fashion? Probably. But one can say that of nearly every professional endeavor.
So when someone describes "exceptional talent" I'm thinking of the sort of talent where someone can design something of a sort that has never been tried before and get it right the first time. There are people like Burt Rutan who have designed some amazing aircraft and spacecraft . He's an exceptional talent. An exceptional engineer (whatever you may think of his morals) was Werner Von Braun, the architect and lead engineer of the Saturn V rocket. Exceptional talent would be the Engineers who designed the SR-71 spy plane (look it up and read about it; this aircraft, designed in the 1960s did things that are incredible even by today's standards).
I also know of some aircraft that, well, don't fly as well as they should have. Mediocre engineering in a field like this gets you noticed.