| UP 4009 has met its fate. Of the 25 Big Boys built, 8 survive today (4004, 4005, 4006, 4012, 4014, 4017, 4018, and 4023). Despite 17 being scrapped, the survival rate for the Big Boys is at 1 in 3, better than the N&W Y6Bs (apologies to N&W fans). Obtained from Union Pacific Steam: Big Boy Portraits (Bush, Ehernberger) |