As with all the London-designed engines, the Parsival is named after a figure from the Arthurian tales. Sir Parsival, also known as Perceval, is a knight who was raised in the wild and whose lack of knowledge of proper society inhibits his ability to join King Arthur's court and find the Holy Grail, comparable to a flawed sword with a hairline crack in its otherwise dangerous blade. The name Parzival specifically comes from the German romance-poem of the same name, based on Chretien de Troyes' unfinished romance.