6959 4-6-0 GWR Hawksworth Modified Hall 6959 – 6999 & 7900 – 7929

Modified Hall 

Power Classification 5MT
Introduced 1944- 1950
Designer Hawksworth
Company GWR
Weight – Loco 75t 16cwt
               Tender 46t 14cwt
Driving Wheels 6ft 0ins
Boiler Pressure 225psi superheated
Cylinders Outside  – 18.5in x 30in
Tractive Effort 27,275lbf
Valve Gear Stephenson  (piston valve)

 

This was Hawksworth’s development of the 4900 Hall class.

 Hall ex saint Hall introduced in 1924 from rebuilt Saint
 modified 1924 Modified Hall introduced in 1944

The Modified Halls marked the most radical change to Swindon Works’ practice since Churchward’s time as Chief Mechanical Engineer. Hawksworth’s use of plate frames throughout the design was a break with Churchward’s practice for 2 Cylinder locomotives. The cylinders were cast separately from the smokebox saddle and bolted to the frames on each side. A stiffening brace was inserted between the frames and extended to form the smokebox saddle. The exhaust pipes leading from the cylinders to the blastpipe were incorporated into this assembly.

Additionally, Churchward’s bar framed bogie which had been adapted for the original Hall in 1924 was replaced by a plate frame structure with individual springing. There were changes too above the running board. Hawksworth decided that the declining quality of coal reaching Great Western depots necessitated a higher degree of superheating. A larger three-row superheater and header regulator were fitted into Swindon No.1 boiler. Improvements were subsequently made to the draughting on some engines, while others were fitted with hopper ashpans.

One of reasons for Hawksworth modifying the design was to make it more able to deal with coal of varying quality which was an issue at the time.

Sixty-one locomotives were built (6959-6999 and 7900-7929) between 1944 and 1950. 6959 – 6970 were built during the Second World War.

They were built without cabside windows to assist with blackout regulations and they ran without names for two or three years. The cabside windows were fitted in 1945 – 1948.  They were known as being very free steaming and free running and were capable of some sustained high-speed running. Indeed, 7903 Foremarke Hall set a post-war record for a run from Paddington to Plymouth: deputising for a failed Castle, the engine completed its journey in under four hours.

After the nationalisation of British railways in 1948 British Railways continued construction of this Great Western class until 1950.

Some modified Halls were equipped with a flat, high-sided Hawksworth tenders. Once he became Chief Mechanical Engineer, many earlier locomotives also received these tenders so a Hawksworth tender does not necessarily mean a Hawksworth locomotive.

End of Year

 Built Withdrawals

No. in Service

Numbers

Quantity
1944 6959-70

12

 12
1947 6971-80

10

 32
1948 6981-95

15

 47
1949 6996-99

  4

 51
  7900-6

  7

 58
1950   7907-29

 23

 81
1951-62

 81
1963

   16

 65
1964

   22

 43
1965

   43

   0

Accidents and Incidents

On 23rd October 2016 6960 Raveningham Hall was hauling a passenger train on the West Somerset Railway up Washford Bank when the when what was described as “a loud noise and a surge between the locomotive and tender” took place. Subsequent inspection at Bishops Lydeard shed revealed that the nut securing the tender clevis to the main drawbar was missing. It was later found at the location of the incident. The West Somerset Railway stated-

“Detailed examination shows that the nut had been drawn clear of the clevis due to the apparent degrading of the threads. The reason for the degraded threadformpart of the ongoing internal investigation. We have kept the ORR and RAIB informed during the process, and the HRA has been advised of the incident should it wish to issue a safety brief to all heritage railways.”

 

Preservation

Since 1996 no Modified Hall class locomotives have been seen or run on the mainline.

Back to GWR

Back to Locomotives