Class 55. I was lucky enough to be granted a private tour of Doncaster Works in 1975. One of the interesting events was a small building where one of the 2 Napier Deltic engines was being repaired. This view clearly shows how the cylinders were arranged in a triangle.
Photo by Michael Taylor, Hamilton, Ontario, Canada. (mtaylor6@home.com)
Website www.members.home.net/mtaylor6