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What's the fastest

steam train on Earth?

Beautiful, sleek, powerful, and capable of reaching speeds of
125m ph. Introducing the Mallard steam locomotive ...

Double chimney Kylchap blast pipe Steam circuit Boiler
Before the Mallard, This network of pipes drew steam Water in this boiler is heated into
traditional steam trains had through the engine, driving the
been fitted with just one wheels and then being vented
chimney, which limited through the exhaust.
their exhaust rate.

Driving wheels
The Mallard's huge 6 foot 8 inch drive
The Mallard's streamlined wheels meant that the maximum
shape helped it reach revolutions per minute for the engine could
speeds of over !OOmph. be reached, again maximising its speed.

team engines use coal-powered boilers wind tunnel, meant it could run at over 10omph What was the Kylchap
to generate steam, which is funnelled for extended periods of time. However, the
S under pressure down a series of pipes, secret of its success lay in its double chimney, blast pipe?
known as a steam circuit. This steam moves which allowed for faster venting of exhaust
The Kylchap blast pipe used four stacked nozzles, the
pistons that are attached to the train's wheels, gases at speed and its Kylchap blastpipe. I first taking exhaust steam, which fed into the second,
and this is what drives them. The exhaust Mallard was the first locomotive of her type to where the exhaust steam was mixed with gas from the
steam is then released via the funnel at the be fitted with this system from new. Its four smokebox. This flowed into a third that
added more exhaust gasses and this
front of the train. The system is effective, but if linked exhaust pipes draw more exhaust gas mixture, then into a fourth, which
the boiler is put under too much pressure it can through the system at a greater speed and with led to the engine's chimney.
This meant that the flow of
explode, devastating the engine and killing or an even flow, minimising wear and ensuring gas was more even through
injuring the crew. Likewise, the exhaust has to that the boiler, steam circuit and pistons could the engine and greatly
be as efficient as possible, drawing steam and work at maximum efficiency. increased its efficiency.
exhaust fumes out to both minimise pressure Mallard was literally built for speed, and on 3
in the system and to allow more steam to be july 1938 it reached 125.88mph on East Coast
drawn through ata greater speed. Main Line, south of Grantham. Mallard still
This is where the Mallard excelled; holds this record, making it the fastest steam
everything about this locomotive was designed locomotive in the world, not to mention one of
for speed. The streamlined body, tested in a the most beautiful.

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