Seventy-five years ago Mallard broke the world speed record for steam locomotives. Bob Gwynne, assistant curator of rail vehicles at York’s National Rail Museum, tells the story of the “secret” run that entered the history books

AS driver Joe Duddington climbed into the cab of the Mallard steam locomotive on July 3, 1938, he probably didn’t realise he was about to attempt a world speed record.

He and fireman Tommy Bray would probably have known in advance they were involved in some kind of test for a new braking system, but not a bid to enter the record books.

Mallard reached a world record for steam locomotives of 126mph on Stoke Bank, South of Grantham, on the East Coast Main Line. The record still stands today.

The achievement is being celebrated by the National Railway Museum, in York, with a Mallard 75 series of events and activities Mallard was designed by Sir Nigel Gresley, widely regarded as one of Britain’s most gifted locomotive engineers and who rose to become chief mechanical engineer of the London and North Eastern Railway (LNER).

He designed some of the most famous steam locomotives in Britain, including Flying Scotsman and Class A4 4-6-2 Pacific engines including Mallard, Bittern and Union of South Africa.

Gresley’s A1 design Flying Scotsman was the first steam locomotive officially recorded as travelling at more than 100mph. The A4 class was designed to routinely travel at this speed and was created to head up the silver jubilee, Britain’s first streamlined train.

The service was introduced in September 1935 between London and Newcastle, via Grantham, and proved a great commercial success, increasing traffic by more than 12 per cent.

When Gresley, travelling in the rear luggage van, ordered an emergency brake application at 95mph, he was horrified at the results. He decided that a new, quick-acting brake was needed to slow a train from high speed. After two years of development, the quick service vacuum brake valve was ready for LNER approval by the summer of 1938. It was under “cover” of being part of the trial of the brake that the record-breaking run was organised.

THE crew on that July 3 run was made up of LNER staff – driver Joe Duddington, and fireman Tommy Bray, of Doncaster Shed, and Inspector Sam Jenkins, of Liverpool Street. The dynamometer car had a large electric speedometer suspended from the ceiling, calibrated 0-120mph. There was also an intercom (called at the time a loudspeaker telephone) between the locomotive cab and the car enabling communication between the two.

In the dynamometer car was Gresley’s personal assistant, Bernard Adkinson, and LNER rest inspector Dennis Carling, who recorded mile posts and bridges to record the train’s location.

The train left from Wood Green waterworks sidings on its outward journey. Packed lunches were eaten at a siding in Barkston as Jenkins and Bray made the fire up, right to the doors of the firebox.

Going through Grantham the train slowed to 24mph because of trackside work. Then it proceeded to Stoke Tunnel up Stoke Bank, on through Great Ponton station.

At Stoke summit Mallard was running at 74.5mph. Within six miles, with the help of gravity, the train was running at 116mph. Duddington, interviewed by the BBC in 1944, recalled running at 85mph at the top of the climb, after which “I gave Mallard her head and she just jumped to it like a live thing. After three miles the speedometer in my cab showed 107mph then 108, 109, 110 and before I knew it the needle was at 116 and we’d got the record.

“They told me afterwards there was a great deal of excitement in the dynamometer car. ‘Go on old girl’ I thought, “she can do better than this”. So I nursed her through Little Bytham at 123 and in the next one and a quarter miles the needle crept up further, 123-and-a-half, 124, 125 and then for a quarter of a mile while they told me the folks in the car held their breath – 126 mph.”

The Northern Echo:
ALL ABOARD: The record-setting crew of Mallard

The steam was shut off and a brake application made at over 120mph after word was given from the dynamometer car via the telephone link to “ease up now”.

As the train had run at over 120mph between milepost 92 and 90, they had clearly – and by a considerable margin – beaten the record by railway rival, the LMS.

The chief civil engineer later remarked that, had he been asked, he would have been against the run because some of the rails near Tallington were of the 40ft type laid in 1910.

GRESLEY was called at home and given the news that the record had been broken.

Mallard was taken off the train at Peterborough and a standby locomotive took over. Tommy Bray “was grinning from ear to ear,” an observer reported, “and I am told very soon polished off enough beer to match his hectic work with the shovel”.

The LNER press department was in on the secret, arranging for reporters to meet the train on its return and ensure the story was the big splash in the Monday morning papers. Pictures of the locomotive used in the run were issued to the press.

Duddington volunteered to drive after his retirement age because of the outbreak of the Second World War, retiring aged 67 in 1944. Bray became a driver after the war, not infrequently on Mallard, and Inspector Sam Jenkins carried on working until 1956.

The record-breaking Mallard was listed as the one Gresley Pacific to be officially preserved by the state. Like all locomotives to be withdrawn it returned to the place it was built. In 1963 the process began at Doncaster Works to restore it back to its 1938 garter blue livery and condition ready for preservation as the locomotive that broke the world speed record.

As part of the Mallard 75 celebrations, the NRM is bringing together the six remaining class A4 locomotives. Two have been repatriated from the US and Canada, and been treated to a cosmetic overhaul for the occasion.

Tomorrow, 75 years to the day, all six locomotives will be reunited around the turntable at the museum in York – a sight never seen before.

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