A 1931 Standard stock tube train

This is a rare colour photo from the 1930s. It shows a bright red Tube train with cream roof and window surrounds. The train is 1931 Standard tube stock. The Standard design was introduced in 1923, when many new trains were built to accommodate growing passenger demand. A key feature was the replacement of manually operated doors with automatic air-powered ones. The photo was taken on the Piccadilly line at Hammersmith Underground station.