LNWR Improved Precedent Class

The London and North Western Railway (LNWR) Improved Precedent class or Renewed Precedent class is a class of 2-4-0 steam locomotive originally designed for express passenger work. They later gained the nickname of Jumbos.

LNWR Improved Precedent Class
No. 1194 Miranda
Type and origin
Power typeSteam
DesignerF. W. Webb
BuilderCrewe Works
Build date1887–1901
Total produced158
Specifications
Configuration:
​
 • Whyte2-4-0
 • UIC1B n2
Gauge4 ft 8 1⁄2 in (1,435 mm) standard gauge
Leading dia.3 ft 6 in (1,067 mm) + 3-inch (76 mm) tyres
Driver dia.6 ft 9 in (2,057 mm)
Wheelbase
  • Coupled: 8 ft 3 in (2.51 m)
  • Loco: 15 ft 8 in (4.78 m)
Loco weight35.60 long tons (36.17 t; 39.87 short tons)
Fuel typeCoal
Water cap1,800 imp gal (8,200 l; 2,200 US gal), later 2,000 imp gal (9,100 l; 2,400 US gal)
Boiler pressure150 lbf/in2 (1.03 MPa)
Heating surface1,063.7 sq ft (98.82 m2)
CylindersTwo, inside
Cylinder size17 in × 24 in (432 mm × 610 mm)
Valve gearAllan
Performance figures
Tractive effort10,918 lbf (48.6 kN)
Career
Operators
Power classLMS: 1P
Number in class1 January 1923: 76
NicknamesJumbos, large Jumbos
Withdrawn1905–1933
DispositionOne preserved, remainder scrapped

History
No. 1532 Hampden with a non-standard chimney

The locomotives were designed by F. W. Webb. A total of 158 were built in batches by Crewe Works 1887–1897 with two further additions in 1898 and 1901 respectively. They were officially "renewals" (i.e. replacements) of 96 Newton Class and 62 Precedent Class, so that, for accountancy purposes, they could be charged against the Revenue account rather than the Capital account of a "new" locomotive. On renewal, they kept the numbers and names of their predecessors, and as a result the numbering system continued to be completely haphazard. In addition, the eight Precedent class locomotives that were not renewed, were rebuilt to the Improved specification, but they retained their original 7⁄8-inch (22.2 mm) thick frames, whereas the renewed locomotives had 1-inch (25.4 mm) frames.

On 22 August 1895, 790 Hardwicke took 2 hours and 6 minutes for the 141 miles (227 km) from Crewe to Carlisle, with an average speed of 67.1 mph (108.0 km/h), setting up a new speed record during the Race to the North.

Withdrawals started in December 1905.

The London, Midland and Scottish Railway acquired 76 upon the grouping of 1923, and gave them the power classification 1P. The LMS assigned these the numbers 5004–79, in order of build date, though not all received them as withdrawals continued apace. By the end of 1933, only 5001 Snowdon survived and in April 1934 it was renumbered 25001 to clear the number 5001 for an LMS Stanier Class 5 4-6-0, but was withdrawn in October that year.

Accidents and incidents
  • On 15 August 1895, locomotive No. 275 Vulcan was one of two locomotives hauling an express passenger train that derailed at Preston, Lancashire due to excessive speed on a curve. One person was killed.[1]
  • On 27 October 1895, locomotive No. 790 Hardwicke was hauling an express passenger train that collided with a freight train at Preston. The express was derailed and Hardwicke was severely damaged. The accident was caused by the driver of the freight misreading signals.[2]
Main article: Weedon rail crashes
  • On 14 August 1915, a locomotive hauling a passenger train suffered a mechanical defect which resulted in track being damaged at Weedon, Northamptonshire. Locomotive No. 1189 Stewart was one of two hauling a mail train that was derailed on the damaged track. Ten people were killed and 21 were injured.

Preservation
No. 790 Hardwicke hauling a passenger train from Carnforth to Grange-over-Sands in May 1976

One, No. 790 Hardwicke (built 1892, LMS No. 5031, withdrawn 1932) has been preserved as part of the National Railway Collection. It was overhauled in 1976 and hauled some excursion trains on the main line, on one of which it double-headed with Flying Scotsman. In the same year it made a special run on the Settle - Carlisle railway, double heading with Midland compound 1000, to celebrate the line's centenary. During this period it was allocated TOPS number 98 190.[3]

It is currently a static exhibit in The National Railway Museum in Shildon.

Fleet list

† LMS number allocated, but never applied

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gollark: Look at the i5-7200U vs i5-8250U. They have the same 15W TDP (not that Intel make that very meaningful) but the 7200U has half the cores and higher base clocks.
gollark: Yes. They used to have 2 cores.
gollark: If you look at the mobile lineup for 7th gen vs 8th gen, you see that 8th gen has a lot more cores and also worse clocks.
gollark: Er, not their laptops, their mobile CPUs.

References
  1. Trevena, Arthur (1981). Trains in Trouble: Vol. 2. Redruth: Atlantic Books. p. 7. ISBN 0-906899-03-6.
  2. "Railway Collision at Preston". The Times (34719). London. 28 October 1895. col D, p. 10.
  3. Harris, Roger (2004). The Allocation History of BR Diesels & Electrics (Part Four). Roger Harris, Bromsgrove, UK.

Sources
  • Baxter, Bertram (1979). Baxter, David (ed.). British Locomotive Catalogue 1825–1923, Volume 2B: London and North Western Railway and its constituent companies. Ashbourne, Derbyshire: Moorland Publishing Company. pp. 188–191. ISBN 0-903485-84-2.
  • Casserley, H. C. & Johnston, Stuart W. (1974) [1966]. Locomotives at the Grouping 3: London, Midland and Scottish Railway. Shepperton, Surrey: Ian Allan. pp. 58–59. ISBN 0-7110-0554-0.
  • Yeadon, W. B. Yeadon's Register of LNWR Locomotives, Volume 1: Passenger Tender Engines.CS1 maint: ref=harv (link)

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