London and North Eastern Railway locomotive numbered 4468 Mallard is a Class A4 4-6-2 Pacific steam locomotive built at Doncaster, England in 1938. It is historically significant as the holder of the world speed record for steam locomotives.[1]

The A4 class was designed by Sir Nigel Gresley to power high-speed streamlined trains. The wind-tunnel-tested,[2] aerodynamic body and high power allowed the class to reach speeds of over 100 miles per hour (160 km/h), although in everyday service it rarely attained this speed. No regular steam-hauled rail service in the UK reached even 90 mph, much less 100. Mallard covered almost one and a half million miles (2.4 million km) before it was retired in 1963.

It was restored to working order in the 1980s, but has not operated since, apart from hauling some specials between York and Scarborough in July 1986 and a couple of runs between York and Harrogate/Leeds around Easter 1987. Mallard is now part of the National Collection at the United Kingdom's National Railway Museum in York. On the weekend of 5 July 2008, Mallard was taken outside for the first time in years and displayed beside the three other A4s that are resident in the UK, thus reuniting them for the first time since preservation. It departed the museum for Locomotion, the NRM's outbase at Shildon on 23 June 2010, where it was a static exhibit, until it was hauled back to York on 19 July 2011 and put back on display in its original location in the Great Hall.

The locomotive is 70 ft (21 m) long and weighs 165 tons, including the tender. It is painted LNER garter blue with red wheels and steel rims.

Mallard is the holder of the world speed record for steam locomotives at 125.88 mph (202.58 km/h). The record was achieved on 3 July 1938 on the slight downward grade of Stoke Bank south of Grantham on the East Coast Main Line, and the highest speed was recorded at milepost 90¼, between Little Bytham and Essendine. It broke the German (DRG Class 05) 002's 1936 record of 124.5 mph (200.4 km/h). The record attempt was carried out during the trials of a new quick acting brake (the Westinghouse "QSA" brake).

Mallard was a very good vehicle for such an endeavour. The A4 class was designed for sustained 100+ mph (160+ km/h) running and Mallard was one of a few of the class that were built with a double chimney and double Kylchap blastpipe, which made for improved draughting and better exhaust flow at speed. (The remainder of the class were retro-fitted in the late 1950s). The A4's three-cylinder design made for stability at speed, and the large 6 ft 8 in (2.03 m) driving wheels meant that the maximum revolutions per minute was within the capabilities of the technology of the day. Mallard was four months old, meaning that it was sufficiently broken-in to run freely, but not overly worn. Selected to crew the locomotive on its record attempt were driver Joseph Duddington (a man renowned within the LNER for taking calculated risks) and fireman Thomas Bray.[3]

In the words of Rob Gwynne, Assistant Curator of Rail Vehicles at the National Railway Museum:

Duddington, then aged 61, climbed into the cab, turned his cap around (as had George Formby in the contemporary film No Limit), and drove Mallard into the history books. He had 27 years on the footplate, and had once driven the Scarborough Flyer for 144 miles at over 74mph (average speed), considered at the time to be the highest speed ever maintained by steam in the UK.[citation needed]

The A4 class had previously had problems with the big end bearing for the middle cylinder, so the big end was fitted with a "stink bomb" of aniseed oil which would be released if the bearing overheated. Shortly after attaining the record speed, the middle big end did overheat and Mallard had to limp onwards to Peterborough. It then travelled to Doncaster for repair. This had been foreseen by the publicity department, who had many pictures taken for the press, in case Mallard did not make it back to Kings Cross. The (Edwardian period) Ivatt Atlantic that replaced Mallard at Peterborough was only just in sight when the head of publicity started handing out the pictures.
Mallard builder's plate with works' number 1870

Stoke Bank has a gradient of between 1:178 and 1:200. Mallard, pulling a dynamometer car and six coaches, topped Stoke Summit at 75 mph (121 km/h) and accelerated downhill. The speeds at the end of each mile (1.6 km) from the summit were recorded as: 87½, 96½, 104, 107, 111½, 116 and 119 mph (141, 155, 167, 172, 179, 187 and 192 km/h); half-mile (800 m) readings after that gave 120¾, 122½, 123, 124¼ and finally 125 mph (194, 197, 198, 200 and 201 km/h). The speed recorded by instruments in the dynamometer car reached a momentary maximum of 126 mph (203 km/h).

On arrival at King's Cross (just after the run) driver Joe Duddington and Inspector Sid Jenkins were quoted as saying that they thought a speed of 130 mph would have been possible if the train had not had to slow for the junctions at Essendine. In addition at the time of the run there was a permanent way restriction to 15 mph just north of Grantham which slowed the train as they sought to build up maximum speed before reaching the high speed downhill section just beyond Stoke tunnel.[4]

On 3 July 2013, Mallard celebrated 75 years since achieving the world speed record, and to help commemorate this date all six surviving Class A4 locomotives were brought together around the turntable in the Great Hall of the National Railway Museum at York for a two-week 'great gathering'. The visitors include three UK based, privately owned engines in 4464 Bittern, 60007 Sir Nigel Gresley and 60009 Union of South Africa (formerly Osprey). Mallard's two internationally based sisters, 60008 Dwight D. Eisenhower and 60010 Dominion of Canada, were present after completing extensive transatlantic journeys, and undergoing cosmetic restoration at the NRM's workshops.[1]
Rival claims

Mallard's world record has never been officially exceeded by a steam locomotive, though the German Class 05 was at least very close: in 1936, two years before Mallard's run, 05 002 had reached 200.4 km/h (124.5 mph) between Hamburg and Berlin. Stoke Bank is long, straight and slightly downhill, whereas the 1936 run of 05 002 took place on a horizontal stretch of track. Unlike world records for cars and aircraft, there is no requirement for an average of two runs in both directions, and assistance from gradient or wind has always been acceptable in rail speed records. Also, unlike Mallard, 05 002 survived the attempt undamaged: on the other hand, its train was only four coaches long (197 tons), whereas Mallard's train was seven coaches (240 tons).[5] In terms of rival claims, Gresley and the LNER had just one serious attempt at the record, which was far from a perfect run with a 15 mph (24 km/h) permanent way check just North of Grantham. Despite this a record was set.[6] Gresley planned to have another attempt in September 1939, but this was prevented by the outbreak of World War II.[7] Before the record run on 3 July 1938, it was calculated that 130 mph (210 km/h) was possible, and in fact Driver Duddington and LNER Inspector Sid Jenkins both said they might well have achieved this figure had they not had to slow for the Essendine junctions.[6]
Mallard record plate

Thus, Mallard still officially holds the record; plaques affixed to each side of the locomotive commemorate the feat.
1948 Locomotive Exchange Trials

In 1948, shortly after the formation of British Railways, the decision was taken to test locomotives from all of the former 'Big Four' companies to find the best attributes of speed, power and efficiency with coal and water. There were two ways of testing and comparing locomotives: either at the Rugby Locomotive testing plant, which was not ready until late 1948 or by testing in the field itself. The results of these trials would be used to help design the British Railways Standard locomotives.

The express passenger locomotive designs which would be compared were: London Midland Region (former LMS) Princess Coronation class, Eastern Region (former LNER) Class A4, Southern Region (former Southern) Merchant Navy class and Western Region (former GWR) 6000 Class or King class.
"Mallard" with the number 'E22' during the Locomotive exchange of 1948

Three Gresley A4 locomotives were chosen to represent the Eastern Region: E22 Mallard, 60033 Seagull and 60034 Lord Faringdon. All of the locomotives had the Kylchap double blastpipe chimney arrangement and were fresh from Doncaster works. Mallard had emerged from Doncaster with a fresh coat of post-war garter blue livery, stainless steel numbers 22 with a small 'E' painted above them (for Eastern region), new boiler (its fourth) and third tender of its career.

E22 Mallard was used on 8 June 1948 on the Waterloo-Exeter route. Driver Marrable took the famous A4 with a load of 481 tons tare, 505 tons full, the same that had been used on the previous trip by 35018 British India Line. Mallard reached Clapham Junction in 6 minutes 57 seconds and Woking in 28 minutes 47 seconds. At Hook there were adverse signals, causing Mallard to slow to a crawl. Even so, Salisbury was reached in 108 minutes and 28 seconds. Despite the signals earlier, the train was only 5-and-a-half minutes late. The net time was 95.5 minutes.

Mallard failed after this trial and 60033 Seagull took over. On 10 June Seagull achieved the run in 96 minutes 22 seconds, but had departed 3 minutes late, meaning Seagull had arrived with the same load 3.5 minutes early. For Mallard, the 1948 Locomotive Exchange Trials were over, but Mallard returned to the Waterloo-Exeter line for a Locomotive Club of Great Britain (LCGB) railtour on 24 February 1963.