31120 is a Diesel owned by the Other Railway who appeared at Barrow in the last illustration of Fire Escape. His headcode is "1X01", which is odd, as the "X" indicates "Royal Train" or "out-of-gauge load". It was eventually withdrawn from service in August 1991.
31120 is based on a BR Class 31 diesel locomotive, hence his number and is painted in British Rail "Rail Blue" livery with large yellow warning panels.
- Gordon The High-Speed Engine (cameo)