Steam locomotive performance testing

Various testing work to investigate ways of improving the performance of steam locomotives was carried out for a number of years by the Big Four railway companies and later by the BR Regions. Here is a selection of pictures and diagrams of testing in the very early days of BR under the auspices of the British Transport Commission.

The performance assessment and test work involved monitoring steam engine performance on the rigs and out on the road using the Mobile Test Plant. Various routes were utilised including the Settle - Carlisle line and the Western Region main line.

There were two static locomotive test plants (at Rugby and Swindon) where locos could be put through their paces on a 'rolling road' rig.

The reports, known as 'Bulletins'  were very comprehensive even detailing the type of coal and the colour of the burnt ash. They were available for the general public to purchase and were advertised in the popular enthusiast magazines of the day.


This is the cover of a typical bulletin

For sale

From Trains Illustrated of August 1957 -  10/- was a lot of money then!

The following is a taste of the work undertaken on steam locos old and new as well as work on some of the early diesel locomotives. Some pages include a great deal of detail of the tests undertaken, others not so much.

There's an interesting page here about the use of the dynamometer cars in UK before the Second World War.

Click the link for information and pictures

Bulletin No Date Loco type

Wheel arrangement

1 May 1951 Western Region Hall Class 4-6-0  
2 August 1951 Eastern & North Eastern Region  B1 Class 4-6-0  
3 October 1951 London Midland Region Class 4 2-6-0  
4 January 1952 British Railways Standard Class 4 2-6-0  
5 April 1952 British Railways Standard Class 7 4-6-2 Britannia class
6 May 1953 British Railways Standard Class 5 4-6-0  
7 August 1953 WD Freight Locomotives 2-8-0 and 2-10-0  
8 March 1953 Eastern & North Eastern Region  V2 class 2-6-2  
9 November 1952 SR (Type 3) 1750 HP 1 Co-Co 1 10202
10 January 1954 SR Merchant Navy


11 April 1959 EE Type 1 1000HP diesel Bo-Bo Class 20
12 March 1960 BTH Paxman Type 1 800HP diesel Bo-Bo Class 15
13 July 1959 BR Standard Class 9F 2-10-0  
14 1960? Brush Type 2 1250 HP diesel A1A-A1A Class 31
15 1954 BR Standard Class 8


71000 Duke of Gloucester
16 1958? Southern Region 2,000 HP Main line diesel Electric

1 Co-Co 1


19 1958? English Electric 3,300 HP Diesel-electric DELTIC


20 1958 SR  Merchant Navy class


21 1959 BR/AEI?Sulzer Type 2



Undocumented tests

Here are a couple of pages with pictures from similar early steam performance testing for which I have no record


LMS Black 5



BR Standard 9F fitted with Crosti Boiler


More information about steam testing on BR in the 1940's and 50's can be found in the late Alan Rimmer's  excellent book entitled 'Testing Times at Derby'. (Oakwood Press ISBN 0-85361-628-0).


Back to home page