On 29 April 1977, the first Class 56 locomotive to be constructed by was handed over to British Rail, having been transported from Romania by ship via the port of Harwich. At one point, it was reportedly planned to deliver 20 locomotives each year; however, this ambitious schedule did not come to pass without consequence. The 30 Romanian locomotives (Nos. 56 001 – 56 030) were found to have a relatively poor build quality; to effectively address this, the majority had to be withdrawn from service for extensive rebuilding within their first few years of operation, after which they were re-introduced to service with better performance.