Didn't I read somewhere (or is it just an FS urban legend?) that the Comet was supposed to be part of the default aircraft in FS9 after someone mentioned it being quite a famous plane (being the first jetliner) but someone at MS tasked to find out and knowing little about these things looked up de Havilland Comet and found the DH88 racer which in it's time was famous as well, so they made that instead.