What if the 5AT isn’t approved to run at 200 km/h?

In fact we recognize that it will be impossible to gain approval to run any faster than 75mph in its initial period of life.  We would hope that lifting of the limit to 90 mph would be granted after the locomotive has proved itself safe when running at 75mph for some (unknown) period of time.  Whether approval would be granted to increase the limit to 110 or 115 mph is obviously an unknown at this stage.  But as Wardale pointed out in a recent letter: “The whole project stands on the ability of the 5AT to run steam trains significantly faster than at present, thereby avoiding them running for long stretches on slow lines, as Tornado has had to do.  And what when the slow lines get faster and more congested, which is sure to happen? Without realizing its speed potential, the rationale of the 5AT simply falls away.”