httpv://www.youtube.com/watch?v=ReGZFiyYPjQ&feature=player_embedded
Easily recognizable and holder of the world speed record for steam locomotives, the British Class A4 Pacifics “LNER Mallard” can be yours in Train Simulator 2013.
The Railsimulator team made good efforts in the whole reproduction of the machine, with real life recordings to make a custom soundset for instance. More infos and screens here.