"Tornado" was granted an Engineering Acceptance (EA) certificate on 31 October by DeltaRail and a Route Acceptance certificate on 3 November by Network Rail, allowing testing on the main line to begin. Further tests were performed at Network Rail facilities located between York and Darlington, at a testing facility known as a wheelchex. This consists of track fitted with sensors to measure vertical force effects such as hammer blow. Completion of a test run between York and Leeds on 28 January 2009 signalled the gaining of certification to haul passengers on the Network Rail main line.