London Underground C69 and C77 Stock

The London Underground C69 and C77 Stock, commonly called the C Stock, was sub-surface rolling stock used on the Circle, District and Hammersmith and City lines between 1970 and 2014, and was replaced by the S7 Stock. In May 1968 an order for 212 cars was placed with Metro-Cammell of Washwood Heath to replace O Stock and P Stock on the Circle and Hammersmith and City lines, for delivery from 1969, and the C69 stock first entered service on 28 September 1970. It used a load-bearing aluminium underframe with a riveted-panel body, four double sets of air-operated sliding doors per side, mainly transverse seating and 32 seats per car. Driving motor and trailer cars formed semi-permanent two-car units, run as six-car trains, with Brush DC motors, four on each driving motor car.