The Peppercorn Class A1 60163 Tornado steam train travels over the Ribblehead Viaduct in Ribblehead, nortern England, for the first time on October 3, 2009 A steam train clocked 100 miles (161 kilometres) per hour on Britain's mainline railway network for the first time in almost 50 years on Wednesday.
Tornado, a Peppercorn-class A1 steam locomotive, reached the landmark speed during a test run aimed at proving it can operate passenger services at 90mph (145 kph).
A steam locomotive has not hit 100mph in Britain since 1968, according to The Daily Telegraph newspaper.
Built by heritage enthusiasts, Tornado hit the three-figure speed on the East Coast Main Line—the route between London and Edinburgh—during a run between Doncaster and Newcastle in northern England.
The test run was part of a bid to raise Tornado's speed limit for passenger services from 75mph (121 kph) to 90mph by the end of this year.
Preservation steam locomotives have been restricted to 75mph since the end of steam services on the main lines in the 1960s.
Tornado was the first steam locomotive to be built in Britain for almost half a century when it was completed in 2008.
If Tornado can run at 90mph it will be able to fit in better with other trains on the busy main railway lines.
Pulling passenger carriages on Wednesday on a secret run, it ran at 10 percent above the 90mph mark to demonstrate a sufficient safety margin.
"We are delighted to have completed the test runs that move us one step closer to 90mph operations with Tornado," said Graeme Bunker-James, operations director for the A1 Steam Locomotive Trust.
"This will allow us to ensure that the locomotive continues to haul trains on the busiest parts of the UK network, allowing as many people as possible to enjoy travelling with Tornado.
"As part of these tests, the locomotive operated at 90mph for a sustained period and also achieved 100mph under these special conditions and running with clear signals."
Workers on the locomotive, their faces blackened, celebrated with a cup of tea after hitting the landmark.
The world speed record for a steam locomotive is 126mph (203kph), set by the Mallard further south on the same railway line in 1938.
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