LNER Peppercorn Class A1

“The Seven Crystal Balls”, a Tintin adventure about the scientists who studied the pyramids of South America and the curse on these people. When I read it for the first time, this was a book that scared me as a kid. There were some scenes in the night, dark scenes with a mummy roaming about. Brrrr…… The opening scene of this book is a huge steam locomotive pulling a fast express train. The passengers were reading a newspaper with a  news piece written from Liverpool. The locomotive pulling this train was developed specifically to pull large heavy express trains at high speeds. This was the London and North East Railways (LNER) Peppercorn Class A1.

Though these locomotives were conceived as part of the LNER, they were commissioned only after the railways were nationalised in Britain as the British Railways. These locomotives were designed by the Chief Mechanical Engineer of LNER, Mr Arther Peppercorn. The name Peppercorn Class was prefixed to A1 to differentiate them from the Sir Nigel Gresley designed A1 Class which were pre-war locomotives. Initially the programme was to rebuild these Gresley A1s as the LNER A3s, but later a new locomotive was designed in 1948. 49 Peppercorn A1s were manufactured at Doncaster and Darlington Works in 1948 and 49. The last one was manufactured in 2008 to fill up the gap left by none of the previous 49 being preserved for posterity.

These locomotives were named after Race horses, important people, works of Sir Walter Scott, pre-grouping railway companies of Britain, birds and places in Britain.

The Peppercorn A1s were deployed on the East Coast Main Line, a 393 mile (632 KM) long route connecting London with Edinburgh. They were designed to pull heavy express trains on this busy route. The trains comprised up to 15 coaches pulled at a speed of 60-70 mph (95-110 km/h) on flat land. A second class, the A2 was also manufactured to pull trains in the hills. The Peppercorn A1 were a 4-6-2 arrangement, meaning a 4 wheel forward bogie, followed by six driving wheel and a 2 wheel trailing bogie. Of these wheels, the leading wheels had a diameter of 3′-2″ (0.965 m) while the trailing wheels had a diameter of 3′-8″ (1.118 m). The driving wheels were massive 6′-8″ (2.032 m).

Theses locomotives were 72′ 11-3/4 ” (22.24 m ) long, 9′ 2-7/8″ (2.82 m) wide  and 13′ 1” (3.99 m ) tall. They weighed in at 106.9 tons. The tender weighed in at 61.9 tons). These coal fired engines had three cylinders. The firebox fire-gate was 50 sq-ft (4.65 m2) while the boiler 6′ 5″ (1.96 m) in diameter and 29′ 2″ (8.89 m) in length. This boiler generated steam at 250 psi (1.7 MPa). The locomotive had a superheater included to improve the efficiency of the Rankine cycle. All the steam produced expanded in three cylinders of 19″ (483 mm) bore and 26″ (660 mm stroke). This massive locomotive could attain maximum speeds of 100 mph (160 km/h) and produced 2000 KW (2682 BHP) of power and 37,400 lb-ft (166 KN) of torque or traction.

These locomotives saw a short service life and all were retired between 1962 and 66 with the push towards diesel and electric traction.