Great Western Society Saint Project • Didcot Railway Centre, Oxfordshire OX11 7NJ • Registered Charity No 272616
The Atlantic Option
An integral part of the Saint Project is the Atlantic Option, allowing for the completed locomotive to run as a Churchward 4-4-2 from time to time in the future. All the work to date has been carried out with this fascinating opportunity in mind.
In 1904 Churchward converted No. 171 Albion (later 2971) to the
4-4-2 wheel arrangement to provide a direct comparison between the Swindon locomotive and the French De Glehn 4-4-2 La France. Favourable results led to 13 more Atlantics being built at Swindon during 1905 as part of the 'Saint' class, to which they were similar in all respects except for the wheel arrangement. This batch of locomotives could be thought of as 'convertible' engines as Churchward was by no means decided on future engine policy at this stage. A combined sub-frame and strengthening plate carrying the rear 4ft 1 1/2in wheels and axle with outside bearings was fitted to the locomotive frames in place of the trailing coupled axle, but the main frames of the 'Atlantics' retained cut-outs to accommodate a trailing coupled wheelset in case conversion should ever be required.
Spot the difference! No. 172 The Abbot (top) was built as an 'Atlantic' 4-4-2. The trailing wheels and axle are carried in outside bearings via a sub-frame bolted to the main frames. Shown for comparison is 4-6-0 No. 175 Viscount Churchill.
Ultimately the superior adhesion of the 4-6-0s set the pattern for the future and all the Churchward Atlantics were indeed converted to 4-6-0s in 1912-13. However, before conversion took place, seven Atlantics were fitted with long-cone superheated boilers, and this is the form in which No. 2999 could appear when running as an 'Atlantic'.
Fortunately the Great Western Society has detailed drawings of the sub-frame assembly, while the wheelset is the same type used for GWR tenders, of which the Society has several spares. Other parts required for running the engine as an 'Atlantic' are springs and spring hangers for the trailing wheels, revised brake gear and two new coupling rods (the front portions of the 'Saint' rods would not be suitable because the forked joint that provides the flexibility in the motion of a six-coupled engine occurs in front of the crank pin on an early 29XX).
Although it is intended that the completed locomotive will run primarily as a 4-6-0, it will also run for periods as a 4-4-2 to illustrate a fascinating and important phase of locomotive development on the Great Western Railway.
No. 189 Talisman seen at Bristol Temple Meads in about 1907 while running as an 'Atlantic' 4-4-2. On the easily graded main line from London to Bristol there was little to choose between the performance of the 4-4-2s and 4-6-0s, but on the steeper routes of the west country the 4-6-0s had the advantage of superior adhesion.
An unidentified Churchward 'Atlantic' heads west through Oldfield Park, Bath, c.1906. This locomotive was from the 1905 batch that came to be known as the 'Scott' series when names related to the Waverley novels were applied to many of them from late 1906 onwards. By 1913 this engine had been converted to a 4-6-0.