LNER Peppercorn Class A1

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Disambiguation: LNER Class A1/A3, LNER Thompson Class A1/1

LNER Class A1 Peppercorn Specification
60133 Pommern passing Leeds-Holbeck High Level Station hauling Leeds Central to Kings Cross Yorkshire Pullman in 1951
Item	Imperial	Metric
Built	1948-1949 (2007, see article)
Number of pieces	49 (+1 under construction, see article)
Numbers of engines	60114 to 60162, (60163 under construction, see article 60163_Tornado)
Wheel Arrangement	4-6-2	2-3-1 (Pacific)
Length over buffers (including tender)	72' 11 3/4"	22.22 m
Maximum Height	13' 1"	3.99 m
Maximum Width (over cab side screens)	9' 2 7/8"	2.82 m
Diameter of driving wheels	6' 8"	2,032 mm
Diameter of bogie wheels	3' 2"	965 mm
Diameter of trailing carrying wheels	3' 8"	1,118 mm
Power (indicated)		approx 2700 PSi
Power (at drawbar)		600-900 PS
Maximum speed	100 mph	160 km/h
Boiler type	Diagram 118
Boiler maximum diameter	6' 5"	1.96 m
Boiler overall length	29' 2"	8.89 m
Boiler pressure (maximum)	250 lb/sq in	17.25 bar
Piston diameter	19"	483 mm
Valve diameter	10"	250 mm
Piston stroke	26"	660 mm
Grate area	50 sq ft	4.65 m²
Heating surface (firebox)	245.30 sq ft	22.79 m²
Heating surface (small tubes)	1211.57 sq ft	112.56 m²
Heating surface (superheater flue tubes)	1004.50 sq ft	93.32 m²
Total evaporative heating surfaces	2461.37 sq ft	228.67 m²
Small tubes diameter	121 x 2 1/4"	57.2 mm
Superheater flues diameter	43 x 5 1/4"	133.4 mm
Superheater heating surface	697.67 sq ft	64.14 m²
Maximum axle load	22 tons 7 cwt	22.7 t
Adhesive weight (full boiler)	66 tons 11 cwt	67.7 t
Weight of locomotive only (full)	105 tons 4 cwt	106.9 t
Total locomotive and tender weight (full)	166 tons 2 cwt	168.8 t
Tender coal capacity	9 tons	9.14 t
Tender water capacity	5,000 gallons (60163: 6,000 gallons)	22.700 l (60163: 27,240 l)
Tender weight (full)	60 tons 18 cwt	61.87 t
Tender wheel arrangement	8 wheels rigid frame
Tender wheel diameter	4' 2"	1,270 mm

Class A1, 'Borderer' primed and ready for duty, by the coaling stage at Gateshead depot.

The London and North Eastern Railway (LNER) Peppercorn Class A1 was a class of steam locomotives. 49 were built to the design of Arthur Peppercorn (who was the last Chief Mechanical Engineer (CME) of the London and North Eastern Railway) during the early British Railways era, but none survived.

The Class has the wheel arrangement 4-6-2 and was powered by three cylinders. The chimney system was of the type Double-Kylchap. The new series was ordered by the LNER but delivered later to British Railways. It was built after the nationalization of private railway companies at Doncaster and Darlington works of former LNER between 1948 and 1949.

Most of the former LNER Class A1 locomotives designed by Sir Nigel Gresley had been rebuilt as LNER Class A3 locomotives prior to this class being conceived. The few straggling LNER Class A1 locomotives that remained unrebuilt during the tenure of Peppercorn's predecessor, Arthur Thompson, were redesignated by him as Class A10s in preparation for the construction of his new Class A1 locomotives. The Thompson A1s were not, however, constructed, these locomotives being built in their place after his retirement.

The locomotives were designed to cope with the heaviest passenger trains in the after-war period at the East Coast Mainline (London – York – Newcastle – Edinburgh – Aberdeen) which consisted normally of trains with up to 15 coaches and up to 550 tons. The ‘’’Peppercorn’’’ A1’s were able to pull such a train on a plain at a speed of 60-70 mph (95-110 km/h.

Above all though the A1s were renowned for their reliability. By 1961 the class had accumulated 48 million miles, equivalent to 202 miles each calendar day. These were unmatched by any other steam locomotive on British Railways. Some of the best performers were put in by Nos 60153-57 which in a move to increase mileage between general repairs were fitted with roller bearing axleboxes. Between 1949 and 1961 this quintet totalled 4.8 million miles with an average mileage between works overhauls of 120,000. In a single year No 60156 Great Central of Kings Cross ran 96,000 miles.

If there was one drawback to the Peppercorn A1 it was its riding. There were wide variations between individual class members with some very rough indeed. The cause apart from the inevitable axlebox wear lay in the leading bogie. This was the same as that fitted to the LNER Thompson Class B1 but no adjustments were made at the design stage to tailor it for the heavier A1. Changes to the loading of the bogie side control springs usually brought the riding up to a level comparable with other express types.

By summer of 1966 all 49 class members had gone for scrap. The last to be withdrawn was no 60145 Saint Mungo after a working life of just 17 years.

[edit] Preservation

As mentioned above no A1 survived into preservation. A fiftieth example, 60163 Tornado (named after the Panavia Tornado) is however being built by the A1 Steam Locomotive Trust and assembled at the old LNER works at Darlington. The A1 Trust hopes that it can be completed by Easter 2008 and from Darlington it will move to the Great Central Railway (preserved) for testing before being allowed onto the mainline. By end 2007 it is 95% complete. When it is finished its first livery - after the standard grey undercoat - will be LNER Apple Green. The importance of Tornado, other than revival of a scrapped class, will be that it will become the first mainline steam engine to be built and completed since the end of steam in Britain.

[edit] Names Of Historic Peppercorn A1 Locomotives

[edit] External links

• LNER encyclopedia
• A1 Steam Locomotive Trust
• Historic A1s 1940s - 1960s