Editing Advanced Passenger Train (section)

===Move to electrification===
While APT-E was still under construction, the team was well into the design of a production version. Jones found an ally in Graham Calder, who had been promoted to become BR's chief mechanical engineer (CME) in 1971. At the time they envisioned building two new experimental trains; one was essentially a stretched version of the APT-E with turbine power, and the other was similar, but powered by [[Overhead line|overhead electrical lines]] via [[Pantograph (transport)|pantograph]] (pan).{{sfn|Gilchrist|2006|p=34}}

As data flowed in from the POP and APT-E, a number of changes to the design were being made. Among the more problematic changes was Leyland's exit from the turbine market, having concluded that the concept of a turbine powered truck was not economically feasible. The company agreed to continue supporting the project anyway, including the release of a more powerful {{convert|350|hp}} version, but made it clear a production design would have to find another solution. In November 1972, the plans changed to build four electric versions for operation on the WCML, and another two turbine versions. From that point the turbine versions fell progressively further behind, and were eventually cancelled.{{sfn|Gilchrist|2006|p=34}}

This may have been a blessing in disguise; the [[1973 oil crisis]] caused fuel prices to rise as much as three times, and turbine engines were notoriously thirsty; the TurboTrain used between 50 and 100% more fuel than conventional sets running on the same routes.<ref>{{cite journal |last=Maurer |first=Charles |title=120-mph train |url=https://books.google.com/books?id=CwEAAAAAMBAJ&pg=PA59  |journal=Popular Science |date=July 1975 |issue=July 1975 |pages=59–61}}</ref> Leyland's use of a recuperator improved this considerably, but proved a maintenance problem.{{sfn|Wickens|1988}}