South African Class GMA 4-8-2+2-8-4


The South African Railways Class GMA 4-8-2+2-8-4 of 1954 was an articulated steam locomotive.
Between 1954 and 1958, the South African Railways placed 120 Class GMA Garratt articulated steam locomotives with a 4-8-2+2-8-4 Double Mountain type wheel arrangement in service. All the locomotives could be configured as either a Class GMA branch line or a Class GMAM mainline engine. This was the most numerous Garratt class in the world.

Manufacturers

The light rail branch line Class GMA and mainline Class GMAM Garratt locomotive, a single Class which could be configured for either branch line or mainline working, was a development of the large Class GM branch line locomotive which was introduced on the South African Railways in 1938. Like the Class GM, the Class GMA was a tank-and-tender Garratt which ran with a semi-permanently coupled auxiliary water tender to augment its meagre water capacity.
The locomotive was designed in 1952 under the supervision of L.C. Grubb, Chief Mechanical Engineer of the SAR from 1949 to 1954. An order for the first 25 of these locomotives was placed with Henschel and Son in Germany. They were built in 1953 and were delivered and placed in service in 1954, numbered in the range from 4051 to 4075. These first 25 locomotives were equipped with Type X-17 water tenders, built by the SAR in its Pietermaritzburg shops in 1953.
A second batch of 35 locomotives was delivered by Beyer, Peacock and Company in 1956. Of these, 23 were built by BP and numbered in the range from 4076 to 4098, while the other twelve, numbered in the range from 4099 to 4110, had been subcontracted by BP to the North British Locomotive Company. These twelve engines therefore bore works plates showing BP as well as NBL as builders.
off no. 4140
This was followed by a third and final batch of sixty locomotives in 1958. Of these, thirty were delivered by BP, of which only ten, numbered in the range from 4121 to 4130, had actually been built by BP. The other twenty, numbered in the ranges from 4111 to 4120 and 4131 to 4140, had once again been subcontracted by BP to NBL. These twenty therefore also bore works plates showing BP as well as NBL as builders. Number 4140 turned out to be the last steam locomotive built by North British. The other thirty locomotives of the third batch, numbered in the range from 4141 to 4170, were again built by Henschel in Germany.
The locomotives of the second and third batches were equipped with Type X-20 water tenders, built in the Pietermaritzburg shops between 1956 and 1958.

Characteristics

The light rail branch line Class GMA and the mainline Class GMAM were the same locomotive of which the water and coal capacities could be adjusted to suit by installing or removing plates in the coal and water spaces. As a result, it is virtually impossible to list the GMA and GMAM versions separately since they could easily be converted back and forth between the two versions and often were. Up until about 1962, for example, the division was 20 Class GMA and 100 Class GMAM, but by 1969 there were 69 Class GMA and 39 Class GMAM, two locomotives having by then been scrapped after accident damage. By 1975, on the other hand, there were only 25 Class GMA against 93 Class GMAM.
The locomotive was thoroughly modern in design, with a one-piece cast steel frame with Franklin spring-loaded wedge horns, manufactured by Commonwealth Steel Castings Corporation in the United States of America. Like the Class 25 locomotive, it had roller bearing axle boxes on all wheels, but not on the crank-pins, with cannon boxes on all axles, except those of the inner Bissel trucks which had outside bearings. It had mechanical lubrication throughout, self-adjusting pivots, a U-shaped foundation ring welded to the inner and outer firebox bottom edges, and an all-welded firebox. The engine units also had Commonwealth cast steel type frames.
The boiler's inside diameter was at the first ring and at the firebox end. The boiler had an inspection manhole, fitted to the top of the boiler aft of the dome. The locomotive was superheated, with a mechanical stoker and Walschaerts valve gear. It could negotiate curves of radius with a gauge widening of not more than and a superelevation of.
Some of these locomotives, intended for working in areas where there were tunnels such as on the East London mainline, were initially equipped with steam-operated smoke deflecting cowls over their chimneys. When the smoke cowls were later removed, these specific locomotives could still be identified by their almost non-existent chimneys which had to be shorter in order to enable the cowls to fit within the loading gauge.
As was done with the predecessor Class GM, the new locomotive carried water only in its front tank, but with the capacity increased from the Class GM's to either for the Class GMA or for the Class GMAM. Likewise, the rear bunker carried only coal, but with the capacity increased from the Class GM's to either for the Class GMA or for the Class GMAM.
As with the Class GM, the Class GMA's water supply was augmented by semi-permanently coupling a purpose-built auxiliary water tender. The first batch of 25 locomotives were tended by the same Type X-17 water tender which was used with the Class GM, with a capacity of between. The rest of the locomotives were tended by Type X-20 water tenders with a capacity of. The tenders were numbered for their engines and were painted black with red buffer beams.
The locomotive was designed to operate on rail despite the maximum axle loading of of the Class GMAM. This had been accomplished by restricting the weight on the leading and trailing bogies to and balancing the coupled wheels so that the hammer blow was equal for all wheels and did not exceed one ton on any wheel at.
Although the SAR specifications called for a maximum axle loading, the Class GMAM spent its entire career running on track that could take or more. Without the restriction of the coal bunker and onboard water tank capacity to and respectively and the necessity to haul along a water tender, the class would have been much more useful and their service lives could possibly have been prolonged. Their shortcomings as traffic machines was possibly one of the root causes of the rapid mainline dieselisation of the SAR in the 1960s.

Service

South African Railways

The 120 locomotives of this class made it the most numerous Garratt class in the world. The Class GMA and Class GMAM saw service on main- and secondary lines in many parts of South Africa. Prior to electrification, a number were employed in Transvaal on the Komatipoort line across the pass between Waterval Onder and Waterval Boven. Along with the Class GM, the Class GMA served on the line from Krugersdorp via Zeerust to Mafeking.
They also served temporarily on the coal line from Witbank to Germiston until the electrification between Witbank and Welgedag was completed. The second and third batches of locomotives were ordered from 1956 to assist with moving large volumes of traffic, mostly coal, from the Transvaal to destinations in the Free State and Cape Province. Until the Class DE-1, the SAR's first road diesels, took over this task late in 1958, they were employed on block coal workings from Witbank to Kroonstad, a distance of. Since the track en route was built for axle loads, such a large order for locomotives with a axle loading was unusual.
In Natal, the bulk of the Class was based at Pietermaritzburg, from where they worked most trains on the two heavily graded branch lines to Greytown and Franklin. Others worked on the Natal North Coast line between Stanger and Empangeni, while some joined the Class GL on the coal line between Vryheid and Glencoe.
The Cape Western system's locomotives were stationed at Worcester, from where they worked the old New Cape Central Railway line via Riversdale to Mosselbaai until it was dieselised. Between 1981 and 1984, a number were allocated to the Cape Northern system to work the line from Vryburg to Mafeking, where they largely replaced the Class 19D locomotives which had earlier dominated on this line. This turned out to be their last term in mainline service since they were replaced by Class 25NC locomotives in 1984 when the line was relaid with heavier rail.
Most of the Class was then allocated to the Cape Midland System in 1984, with most of them initially stationed at Voorbaai where they replaced the Class GEA on trains from Mosselbaai to Riversdale and across the Montagu Pass to Oudtshoorn. Their allocation was later extended to the sheds at Sydenham in Port Elizabeth, Rosmead, Klipplaat and Graaff-Reinet, with the result that they worked most of the trains over the route from Port Elizabeth to Rosmead via Klipplaat and across the Lootsberg Pass from Graaff-Reinet.
Towards the end of their service lives, the Eastern Transvaal system still had an allocation of them, where locomotives from the Waterval Boven and Breyten sheds worked the line down to Vryheid in Natal.
They were the last class of Garratt to remain in service with the SAR. All but three were withdrawn from service by April 1988 and those three were also retired shortly afterwards.
4140 was the last of the class delivered and became the last steam locomotive built by the North British Locomotive Company.

Zimbabwe and Mozambique

During the period from August 1979 to September 1981, altogether 26 locomotives of the Class were hired to Zimbabwe-Rhodesia, but not all at the same time since they were rotated with Capital Park in Pretoria as their nominal home for the occasions when they had to return to South Africa for major repairs. On the Rhodesia Railways, later the National Railways of Zimbabwe, they worked from Bulawayo to Gwelo and to Wankie and beyond to Victoria Falls.
Six of these locomotives were loaned by RR to the Caminhos de Ferro de Moçambique for a short while to work the CFM Centro line from Beira to Umtali in Zimbabwe.
In Zimbabwe-Rhodesia, these locomotives normally worked chimney first with the water tank at the rear. Since the Rhodesian bush war was still ongoing in 1979, the locomotives were equipped with armour plating around the cab. Since this obscured the number plates, the engine numbers were then usually stencilled on the cabsides. The Class GMAM was similar in size with a similar coal capacity to the Rhodesia Railways 20th class 4-8-2+2-8-4 Garratt, but it had a voracious appetite for coal and frequently ran low on fuel with the result that trains often had to be dumped. In an attempt to solve this problem, RR extended the height of the Class GMAM's coal bunker by a foot to increase the capacity.
26 GMAM Garratts were hired to Rhodesia/Zimbabwe between August 1979 to December 1981
+ 4059 Hired to Rhodesia/Zimbabwe 12/1979 to 07/1981
+ 4060 Hired to Rhodesia/Zimbabwe 08/1979 to 09/1981
+ 4064 Hired to Rhodesia/Zimbabwe 08/1979 to 05/1981
+ 4065 Hired to Rhodesia/Zimbabwe 08/1979 to 03/1981
+ 4070 Hired to Rhodesia/Zimbabwe 08/1980 to 02/1981
+ 4071 Hired to Rhodesia/Zimbabwe 12/1979 to 09/1980
+ 4087 Hired to Rhodesia/Zimbabwe 08/1979 to 09/1981
+ 4089 Hired to Rhodesia/Zimbabwe 08/1979 to 10/1981
+ 4090 Hired to Rhodesia/Zimbabwe 12/1979 to 09/1980
+ 4098 Hired to Rhodesia/Zimbabwe 01/1980 to 09/1981
+ 4099 Hired to Rhodesia/Zimbabwe 12/1979 to 03/1981
+ 4102 Hired to Rhodesia/Zimbabwe 09/1980 to 05/1981
+ 4103 Hired to Rhodesia/Zimbabwe 12/1979 to 02/1981
+ 4111 Hired to Rhodesia/Zimbabwe 02/1980 to 02/1981
+ 4112 Hired to Rhodesia/Zimbabwe 08/1979 to 10/1980
+ 4117 Hired to Rhodesia/Zimbabwe 06/1980 to 02/1981
+ 4120 Hired to Rhodesia/Zimbabwe 08/1979 to 10/1980
+ 4121 Hired to Rhodesia/Zimbabwe 12/1979 to 09/1981
+ 4125 Hired to Rhodesia/Zimbabwe 08/1979 to 04/1980
+ 4126 Hired to Rhodesia/Zimbabwe 12/1979 to 01/1980
+ 4129 Hired to Rhodesia/Zimbabwe 03/1979 to 10/1980
+ 4134 Hired to Rhodesia/Zimbabwe 08/1979 to 10/1980
+ 4135 Hired to Rhodesia/Zimbabwe 08/1979 to 02/1981
+ 4137 Hired to Rhodesia/Zimbabwe 08/1979 to 09/1980
+ 4139 Hired to Rhodesia/Zimbabwe 08/1979 to 08/1981
+ 4140 Hired to Rhodesia/Zimbabwe 12/1979 to 08/1981

Industrial, private ownership and preservation

Several locomotives of the class were sold into industrial service and some later were saved for preservation after being sold on into private ownership. The majority went to the Randfontein Estates Gold Mining Company. Two were sold to the Hotham Valley Railway in Western Australia where they were to haul tourists in ex SAR passenger coaches. These two locomotives, 4090 and 4129 however, never left South Africa and after standing at Bloemfontein loco for 20 years, they were scrapped in May 2016. 4074 was rebuilt after REGM service with the boiler cradle off 4126 and therefore is shown listed as such per the Beyer Peacock numbering and locomotive identification protocol.
NUMBERBUILDER/WORKSTHF / PrivateLEASELEND / OWNERCURRENT LOCATIONOUTSIDE SOUTH AFRICA?
4056Hensc 28685THFMAINLINE STEAMWATERVAL BOVEN LOCOMOTIVE DEPOT
4070Hensc 28699THFTHF MUSEUMGEORGE TRANSPORT MUSEUM
4074 Hensc 28703PrivateCREIGHTON MUNICIPALITYCREIGHTON
4079BP 7677PrivateSANDSTONE ESTATEGERMISTON LOCOMOTIVE DEPOT
4083BP 7681PrivateMAINLINE STEAMMERCERNEW ZEALAND
4112BP 7827 / NBL 27770PrivateSummerlee Industrial MuseumCoatbridgeSCOTLAND
4114BP 7829 / NBL 27772PrivateSANDSTONE ESTATEBLOEMFONTEIN LOCOMOTIVE DEPOT
4122BP 7837THFCLASSIC RAILVOORBAAI LOCOMOTIVE DEPOT
4128BP 7843THFCLASSIC RAILVOORBAAI LOCOMOTIVE DEPOT
4135BP 7850 / NBL 27787PrivateCeres Railway CompanyHermanstad
4136BP 7851 / NBL 27788THFMAINLINE STEAMBLOEMFONTEIN LOCOMOTIVE DEPOT

Works numbers

The builders, works numbers and years built of these locomotives are listed in the table.

SAR no.
Builders
Works
no.
NBL
Works no.
Year
4051Henschel286801953
4052Henschel286811953
4053Henschel286821953
4054Henschel286831953
4055Henschel286841953
4056Henschel286851953
4057Henschel286861953
4058Henschel286871953
4059Henschel286881953
4060Henschel286891953
4061Henschel286901953
4062Henschel286911953
4063Henschel286921953
4064Henschel286931953
4065Henschel286941953
4066Henschel286951953
4067Henschel286961953
4068Henschel286971953
4069Henschel286981953
4070Henschel286991953
4071Henschel287001953
4072Henschel287011953
4073Henschel287021953
4074Henschel287031953
4075Henschel287041953
4076BP75501956
4077BP75511956
4078BP75521956
4079BP76771956
4080BP76781956
4081BP76791956
4082BP76801956
4083BP76811956
4084BP77501956
4085BP77511956
4086BP77521956
4087BP77531956
4088BP77541956
4089BP77551956
4090BP77561956
4091BP77571956
4092BP77581956
4093BP77591956
4094BP77601956
4095BP77611956
4096BP77621956
4097BP77631956
4098BP77641956
4099BP/NBL7765276911956
4100BP/NBL7766276921956
4101BP/NBL7767276931956
4102BP/NBL7768276941956
4103BP/NBL7769276951956
4104BP/NBL7770276961956
4105BP/NBL7771276971956
4106BP/NBL7772276981956
4107BP/NBL7773276991956
4108BP/NBL7774277001956
4109BP/NBL7775277011956
4110BP/NBL7776277021956
4111BP/NBL7826277691958
4112BP/NBL7827277701958
4113BP/NBL7828277711958
4114BP/NBL7829277721958
4115BP/NBL7830277731958
4116BP/NBL7831277741958
4117BP/NBL7832277751958
4118BP/NBL7833277761958
4119BP/NBL7834277771958
4120BP/NBL7835277781958
4121BP78361958
4122BP78371958
4123BP78381958
4124BP78391958
4125BP78401958
4126BP78411958
4127BP78421958
4128BP78431958
4129BP78441958
4130BP78451958
4131BP/NBL7846277831958
4132BP/NBL7847277841958
4133BP/NBL7848277851958
4134BP/NBL7849277861958
4135BP/NBL7850277871958
4136BP/NBL7851277881958
4137BP/NBL7852277891958
4138BP/NBL7853277901958
4139BP/NBL7854277911958
4140BP/NBL7855277921958
4141Henschel296001958
4142Henschel296011958
4143Henschel296021958
4144Henschel296031958
4145Henschel296041958
4146Henschel296051958
4147Henschel296061958
4148Henschel296071958
4149Henschel296081958
4150Henschel296091958
4151Henschel296101958
4152Henschel296111958
4153Henschel296121958
4154Henschel296131958
4155Henschel296141958
4156Henschel296151958
4157Henschel296161958
4158Henschel296171958
4159Henschel296181958
4160Henschel296191958
4161Henschel296201958
4162Henschel296211958
4163Henschel296221958
4164Henschel296231958
4165Henschel296241958
4166Henschel296251958
4167Henschel296261958
4168Henschel296271958
4169Henschel296281958
4170Henschel296291958

Illustration