Part 5/11:
Undeterred, engineers designed a more advanced prototype called Big Willie. This vehicle boasted a weight of 30 tons, a 10mm thick front armor, dual 57mm guns, and the ability to meet operational requirements such as a top speed of at least 6.5 km/h, crossing 1.5-meter-high walls, and navigating trenches 2.5 meters wide. Although kept secret from the wider military and political leadership, Big Willie demonstrated the potential of armored vehicles during inspections in early 1916.