South African Railways Beyer-Garratt Locomotives in South_Africa

Class FC (Locobase 13096)

Data from Gustav Reder (Michael Reynolds, trans), The World of Steam Locomotives (New York: Putnam, 1974), p.255; and "'Modified Fairlie' Locomotive for the South African Rys", Locomotive Magazine, Volume XXXI [31] (15 June 1925), pp. 168-170. Works number was 23140 in 1925.

Designed as a "modified Fairlie", this engine has a double firebox and two boilers on a single rigid frame. The two sets of engine bogies pivot underneath, showing that this actually was a Kitson-Meyer type. LM's report reproduced Collins's claims that putting the boiler, firebox, grate and both tank and bunker on the rigid frame meant all axles bore their share of the weight as the enigne consumed water and coall

Reder explained that SAR's Lt Colonel F R Collins obtained this batch of engines to see if they could offer competition to the Beyer-Garratts, then monopolizing the articulated stud. Alas, reports Reder, "In negotiating curves, the pivot pins came under too much stress due to the pronounced lateral sway of the long overhangs. These engines thus proved more expensive to maintain than the Garratt locomotives, and as a result were soon scrapped."

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Class FD (Locobase 2484)

Data from Holland, Volume II (1972), pp. 50-51. Works numbers were 23294-23297 in 1926.

As explained in Locobase 13096, the "Modified Fairlies" that Colonel FR Collins ordered were actually very similar to Kitson-Meyers, although the firebox layout was different. In any case, they were "...not very satisfactory" says Holland. "[T]he long overhang at front and back tended to vibrate in an up-and-down directions when the engine was in motion with a consequent setting up of metal fatigue and cracking of the frames."

Otherwise, Holland concedes, they were "powerful and good steamers", but did not last long in service.

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Class GA (Locobase 745)

Data from Holland (1972,II), pp. 41; "'Garratt' Locomotive for the South African Railways', Locomotive Magazine, Volume XXVII [27] (14 May 1921), pp. 113-114; M C Williams, "The Advantages of Articulated Locomotives", Railway Gazette, Volume 37, No 5 (4 August 1942), pp. 160-167; and "Recent 'Garratt' Patent Locomotives", Railway Engineer, Volume 43, No. 5 (May 1922), pp. 184-186. See also Peter Ball, "The Big Fiery Giant - The Story of the Beyer-Garratt Locomotive", The Heritage Portal (South Africa), dated Tuesday, November 17, 2015 - 15:43, at []; and "Garratt Articulated Locomotives", Railway Age, Volume 74 (14 April 1923), p. 959. Works number was 5941 in 1918.

Trialled by the SAR for main-line service, this engine effectively ended Mallet articulated locomotive procurement in the South Africa. According to Holland (1972, II), the GA Mogul Garratt "...took greater loads ...running times were better, also coal and water consumption were lower." Average advantages included about 10% greater load running over the road in less time consuming 11% less fuel and weighing almost 40 tons (89,600 lb or 40,642 kg) less.

Peter Ball added some detail to Durrant's summary, beginning with the nicely tongue-in-cheek characterization of a competition that had "come down to just a two (iron) horse race ...between the Mallet and the Beyer-Garratt." [Ball's parens in the original; it was a South African locomotive historian who coined the term "ferro-equinologist".].

The Garratt was the GA shown here and the North British Locomotive Company MH class 2-6-6-2 Mallet found in Locobase 2866. The "race course" would be the former Natal main line between Durban on the coast and Ladysmith up on the Highveld plateau. "[G]radients were as steep as 1 in 30 [3.33%] and curves as tight as 4 1/2 chains radius (just under 300 feet [91.4 m]."

RA's report dedicated several paragraphs describing the Garratt idea to readers who might not be familiar with the concept. After laying out the arrangement--"in reality simply two plain [i.e. simple expansion] engines with one large boiler"--the author focuses on the "practically unlimited latitude" in boiler design whose capacity may be "all that is required". Grate area "may be ample for even low grade fuels, while the volume of the firebox and the height from the grate to the crown sheet may be proportioned to give good combustion without resorting to an additional chamber." In sum, "a plain rectangular box--with a brick arch" made of three plates, two seams, and "easily stayed."

Pivot castings at the front and back of the boiler unit provided positive weight distribution. Moreover, the setup didn't require weight adjusting links or lateral control, so "running is as free as with two separate small locomotives."

While the tests showed the basic concept's superiority to the basic Mallet (which was by no means a bad design), the GA's lack of a trailing truck on the lead engine unit and a leading truck on the trailing engine unit inflicted flange wear on the drivers. All succeeding SAR Garratts, of which there were many, used a balanced-truck layout on each of the two engine units.

Problems with frame cracking led to an early retirement in 1938.

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Class GB (Locobase 748)

Data from D F Holland, Steam Locomotives of the South African Railways. 2: 1910-1955 (1st ed.). (Newton Abbott, England: David & Charles, 1972, pp. 41-42; and M C Williams, "The Advantages of Articulated Locomotives", Railway Gazette, Volume 37, No 5 (4 August 1942), pp. 160-167. See also "Recent 'Garratt' Patent Locomotives", Railway Engineer, Volume 43, No. 5 (May 1922), pp. 184-186; Cdr J Plomer, "A Long Line of Mountains", The Railway and Locomotive Historical Society Bulletin, No. 122 (April 1970), pp. 7-25. and "South African Class GB 2-6-2+2-6-2" in Wikipedia at [], last accessed 24 August 2021. Works numbers were 5942 in 1921, 6181-6186 in 1924.

Branch-line Prairie Garratts, the first series production of the type in South Africa. The prototype, delivered in 1921, weighed 160,496 lb each and had 1,049 sq ft of heating surface in 128 tubes and 105 sq ft of firebox and 174 sq ft of superheat surface.

When BP produced the series shown in the specs, says Holland, they supplied a cab design with a more complete enclosure and cab windows. Wikipedia, citing Holland, also reports that the first GB quickly " good riding qualities and flexibility on light track with poor ballasting and many curves of 300 feet (91 metres) radius."

Plomer admitted that the first GB "made a strong impression on my brother and myself walking along the track of busy branch line when she came silently and fast around a sharp curve and we had to jump for it. To show his appreciation the fireman pitch a goodsized lump of coal at us. Anyway he missed."

The class retired in 1967.

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Class GC (Locobase 749)

Data from Weiner (1930). See also Holland (1972,II), pp. 43; and "South African Railway-Design 02400", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [], et seq, p. 38. Works numbers 6187-6192 in 1924.

Prairie Garratts that were heavier than the GBs (Locobase 748) and cylinder volume, heating surface areas grew with an increase in tube and flue number and length. They too had Belpaire fireboxes, four simple-expansion cylinders with piston valves, and a superheater.

B-P's 1931 volume reported several savings in tire wear because the engines didn't have be turned at each end of their runs. Moreover, they allowed passenger-train speeds on their regular runs. B-P explained that in the first five miles (8 km) of a run, a GC could hit speed of 45 mph (72.5 kph). The rest of the run presented inclines of over 3% and very tight curves, but the locomotive could still reach 35 mph (56 kph).

This sextet served Natal State during its entire career, which ended with the last withdrawal in 1962.

Their "excellent" performance inspired more orders and by 1931, a total of 45 had been bought for several parts of the system.

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Class GCA (Locobase 755)

Data from DF Holland, Volume II (1972), pp. 52-53; and South African Railways & Harbors 8 - 1941 Locomotive Diagram book supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. See also [], last accessed 12 June 2016.. Works numbers were 970-982 in 1927, 1043-1068 in 1928.

Branch-line versions of the GC Prairie Garratt class with bar frames, round-topped fireboxes, and a lighter axle load. The second batch, delivered in 1928, weighed more in aggregate, but had a lower maximum axle load. A tendency to break side rods was the design's only failing, says Holland, who attributes the problem to small drivers turned at excessive speeds.

Data from Gavin Hamilton's excellent compilation of Garratt data posted at []

(6 September 2005) shows different values for the EHS -- 1,366 sq ft -- and the superheater -- 226 sq ft -- for a total CHS as 1,592 sq ft. Locobase supposes that Hamilton's numbers were as delivered, while Holland's (taken from a locomotive diagram published in Holland's book) represent a later rebuild.

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Class GD (Locobase 751)

Data from Wiener (1930); and "South African Railway-Design 116", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [], et seq, p. 39-40 See also Gavin Hamilton's site at [] (6 September 2005); and Holland, Volume II (1972), pp.

First batch's works numbers were 6263-6266. Beyer also delivered 2228-2234 (BP 6281-6287) in 1925 and 2235-2237 (BP 6288-6290) in 1926.

Data from Gavin Hamilton's excellent compilation of Garratt data posted at shows 260 sq ft for the superheater for a total of 1,937 sq ft of CHS. Locobase wonders if Wiener described one batch and Hamilton another.

Fourteen of this Double Prairie Garratt class entered service, working Capetown-Caledon (380 short tons on line that included 10 miles of continuous 2 1/2% grade), Durban-north coast (3.33% ruling grade over 124 miles), and Piertermaritzburg-Franklin (2 1/2% continuous grade over 37 miles to a summit of 2,944 ft). They would work trains at speeds up to 45 mph (72.5 kph).

In 1972, Holland's verdict on their utility was quite positive: "They were handy locomotives, trouble-free, and have given good service."

The class was scrapped in 1967.

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Class GDA (Locobase 756)

Data from locomotive diagrams published on [] . See also Holland, Volume II (1972), pp. 61-62; and A[rthur] E[dward] Durrant, Garratt Locomotives of the World (revised edition) (Newton Abbott, UK: David & Charles, 1981), p. 117. Works numbers were 3115-3119 in 1929.

Branch line Double Prairie Garratts that repeated the GD design (Locobase 750) with a round-topped firebox and bar frame. They entered service only for a short time out of Cape Town and then lay idle for several years. Although they were eventually made to work satisfactorily, says Holland, "it has never been explained why it was found necessary to introduce a new class of locomotive of this type when the class GD had been found to be reliable and good locomotives."

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Class GE - 1st order (Locobase 4382)

Data from Holland, Volume II (1972), pp. 31-32; and Reference 153 in South Aftrican Railways & Harbours 8 - 1941 Locomotive Diagrams NG supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange collection. Works numbers were 6193-6198 in 1925.

This was the first of three batches of powerful Double Mikado Garratts for use on the Zeerust-Mafeking and Pretoria-Pietersburg heavy freight service. All had the same boiler, but these first six had slightly more firebox area.

(GEs from the second order appear in Locobase 761 and from the third order in 2907.

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Class GE - 2nd order (Locobase 761)

Data from Holland, Volume II (1972), pp.45; and Reference 153 in South Aftrican Railways & Harbours 8 - 1941 Locomotive Diagrams NG supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange collection. Works numbers were 6339-6348 in 1927.

Two years after the first batch of GE Double Mikados (Locobase 4382), Beyer Peacock delivered this second batch of Double Mikado Garratts in 1927. These had the same boilers, but slightly less superheat and smaller fireboxes.

See Locobase 2907 for the third batch.

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Class GE - 3rd order (Locobase 2907)

Data from Holland, Volume II (1972), pp. 45; A[rthur] E[dward] Durrant, Garratt Locomotives of the World (revised edition) (Newton Abbott, UK: David & Charles, 1981), p 122; and Reference 153 in South Aftrican Railways & Harbours 8 - 1941 Locomotive Diagrams NG supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange collection. Works numbers were 6716-6717 in 1931.

This duo was the third batch of Class GE Double Mikado Garratts first put into service in 1924 (Locobase 4382) and 1927 (Locobase 761), but with cylinders 1"(25.4 mm) larger in diameter and small increases in heating surface including 27 sq ft of arch tubes.

At the time of their introduction, they probably were the most powerful narrow-gauge locomotives in service. Durrant reported that GEs first seved the diffiecult main line between Johnnaesburg-Zeerust. Later the class handled North coast trains from Durban as well as branch line operations from Eshowe and Nkwallini.

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Class GEA (Locobase 768)

Data from Holland (1972, II); and South African Railways & Harbors 8 - 1941 Locomotive Diagram book supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange; and South African Class GEA 4-8-2+2-8-4 in Wikipedia at [], last accessed 19 September 2021. Works numbers were 7168-7227 in 1946.

Firebox heating surface included 27 sq ft (2.51 sq m) of arch tubes. Designed by Dr. M.M. Loubser, Chief Mechanical Engineer (CME), these engines did not use mechanical stokers.

One of the biggest single batches of Garratt locomotives under a single order that were based on the older GEs, these Mountain Garratt engines bore little resemblance to them. In place of the usual structural elements, these featured a frame made of 4" (102 mm) thick rolled steel bars and a round-topped boiler.

Their ambit was the Johannesburg-Zeerust line and the Mossel Bay-Oudtshoorn region. Wikipedia reports that the cabs were particularly well-liked by the crews. The double roof was lined with teak, cab sides

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Class GF (Locobase 765)

Data from diagrams published on the web at [] (visited 5 January 2001); A[rthur] E[dward] Durrant, Garratt Locomotives of the World (revised edition) (Newton Abbott, UK: David & Charles, 1981), p 121. Works numbers 10512-10548 in 1927

Hanomag built the first batch of 37 Pacific Garratt engines to the design of SAR's Col. F R Collins. He was seeking a mixed-traffic, branch-line engine. With the GF's, he achieved that goal once inside-bearing trucks were replaced by outside-bearing ones. Durrant pointed the GFs' bar frame was "a distinct advance," but found the design "marred" by a continued reliance on "old-type cylinders with Z ports and short-lap valves."

That kink worked out, these engines were very successful, which led to another order to Henschel (18 -- works numbers 21053-21070 in 1928) and to JA Maffei (10 -- works numbers 5748-5757 -- also in 1928). Durrant descirbed them as "very useful" on main and branch lines, "being a 'go-anywhere, do-anything'" locomotive..

In their later years, the SAR sold some GFs to industrial users such as Enyaati collieries, where they could be seen "banked, double-headed, or even, on rare occasions, triple-headed! [exclamation point in the original.]"

The SAR sold four--2370, 2419-2420, AND 2432-- to the Mozambique Railways in 1950 as their series 911.

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Class GG (Locobase 750)

Data from Holland, Volume II (1972), p. 47-49; "South African Railway-Design 113", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [], et seq, p. 42.

This was basically a one-off attempt at a Double Prairie Garratt express locomotive. She proved herself capable of 57 mph (92 kph) with a load and she could work up to 1,245 tons up a 1 1/4% grade -- no small accomplishment. Another run took 340 tons up a 2 1/2% grade 15 miles long in 62 minutes.

She proved unsteady at high speeds, however, and was relegated to secondary passenger and freight duties.

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Class GH (Locobase 13099)

Data from DF Holland, Volume II (1972), p. 57; and South African Railways & Harbors 8 - 1941 Locomotive Diagram supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.\). See also Phil Girdlestone & Shaun McMahon, "2ft gauge Little Titans for the Welsh Highland - The 'NGG16s'" published in 1994 and archived at [], last accessed 17 February 2014. Martyn Bane wrote an equally good and comprehensive article on these two Garratts' restoration titled "Alfred County Railway - Garratt 2-6-2+2-6-2 NGG16A Nos. 141 & 155", archived at []. . Works numbers were 5687-5688 in 1928.

Not satisfied with the Union Garratts U-boats already supplied to him by Maffei, Colonel Collins returned to the German builder for two more still bigger engines. Unlike the U-boats, this pair had the short boiler of the pure Garratt. They also had relatively high drivers for use on several expresses.

A significant oversight became apparent on the first trial runs according to Holland when it was found "...that they exceeded the moving structure gauge and scraped the platforms of every station through which they passed." Embarrassing as it must have been in 1928, the latter-day reader can't help but smile at Holland's report of the result: "They returned to Salt River works minus their steps and sundry fittings, and pungent letters were written by various irate stationmasters about the damage done to their platforms! [exclamation point in the original]."

The two engines never proved very successful. The modified Fairlie with its engine units pivoting around a central pivot "...gave trouble by causing broken frames and undue wear, " says Holland. "Further, the long overhange of the cradle frame from the pivot centers caused considerable vertical vibration when running, thus setting up structural weaknesses."

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Class GL (Locobase 766)

Data from Holland, Volume II (1972), p. 61; and "South African Railways, Design No. 1162", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [], et seq, p. 44-46.; and . Works numbers were 6520-6531 in 1929, 6639-6644.

Two arch tubes and two Nicholson syphons contributed to the generous direct heating surface area.

OS Nock (RWC V, pl 66) says these engines scaled the Durban bank to Cato Ridge on 80 lb/yard (40 kg/metre) rail over a permanent way that included 38 miles of 1.5% grade, pulling 1,205 tons around 154 compensated curves. The 4-8-2s these Mountain Garratts replaced could pull 500 tons and took 21 minutes longer. At the time of their introduction, says Holland (1972, II), this class comprised "the most powerful steam locomotives to be placed in service anywhere in the southern hemisphere." In test runs, a GL "easily handled 1,117 tons at 16.4 mph (26.4 kph)", asserted the BP's 1931 report, which it claimed was "world's haulage record for steam on the 3' 6" gauge."

[], put up by David Guelpa of Bloemfontein, has some personal comments about the GLs. From the driver's point of view, it was "a magnificent machine to work. One point was very clear. A driver had to be well acquainted with the GL and to many whom was not (sic) it was a battle to keep the loads moving. Many of them stalled on the upgrades and had to split the load in two in order to clear the section."

Firing the GL: "You either enjoyed the challenge or despised it." Limitations in the automatic stoker's distribution pattern meant that the fireman had to fill in down the middle and at the back. Adding to the backache was the small-diameter coal (1" or so). So fine was this coal that when the engine was being worked hard, it never even reached the grate before igniting.

"It was hard work," concedes Guelpa," but the best days of my life were woring on those mighty GLs."

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Class GM (Locobase 767)

Data from Holland (1972, II); A[rthur] E[dward] Durrant, Garratt Locomotives of the World (revised edition) (Newton Abbott, UK: David & Charles, 1981), pp 129-130; and "Class GM", Reference Item 159, Index of Diagrams of Steam Locomotives" (Pretoria, South Africa: Chief Mechanical Engineer, 1941), p 33. . Works numbers were 6883-6898 in 1938.

Durrant noted the ten-year reign of Chief Mechanical Engineer AG Watson from 1929-1938 in which he studiously avoided ordering more articulated locomotives. As soon as W A J Day took over as CME, he ordered these Double Mountain Garratts, which were essentially GLs designed to a requirement to handle larger trains on the 60-lb/yard (30 kg/metre) rail of the Johannesburg-Mafeking line, whose profile had a sawtooth quality of up and down grades.

These engines trailed a 6,750 gallon (30,659 litre) auxiliary water tank to supplement the meager tender capacity. That small capacity resulted from the SAR's chief civil enginer's demand for a reduction in axle loadings. "The front tank," wrote Durrant, "held only enough water for shunting purposes, and the rear unity held coal only."

Designated for the Zeerust line, "they revolutionised working"in that service

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Class GMA/GMAM (Locobase 769)

Data from South Aftrican Railways & Harbours 8 - 1941 Locomotive Diagrams NG supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange collection; and A[rthur] E[dward] Durrant, Garratt Locomotives of the World (revised edition) (Newton Abbott, UK: David & Charles, 1981), pp 134-135..

Firebox heating surface included 25.2 sq ft (2.34 sq m) of arch tubes. Superheat surface was later reduced to 636 sq ft (59.09 sq m)..

Developments of Beyer, Peacock's pre-war GMs, these two classes of Double Mountain Garratts had cast-steel engine beds, roller bearings, a U-shaped welded foundation ring, mechanical stokers and rocking grates. GMAs had a tender water capacity of 1,650 gallons (7,494 litres) and coal capacity of 11 tons (12.1 short tons). Water capacity was augmented by a permanently coupled trailing tank car holding 6,750 gallons (30,659 litres).

Henschel built the first 20 (works numbers were 28680-28704) and the last 30 (works numbers 29600-29629). Beyer, Peacock and North British split the remainder, Beyer's building 4079-4098 and 4121-4130 and NBLC supplying 4099-4140 (works numbers 27691-27702 in 1956, 27769-27778 and 27783-27792 in 1958)..

They were very successful and well-balanced engines. Holland (1972, II) reports that hammer blow from their drivers didn't exceed 1 ton for any wheel at 45 mph (72 kph).

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Class GO (Locobase 771)

Data from Holland, II; and "South African Class GO 4-8-2+2-8-4" in Wikipedia at .[], last accessed 20 September 2021. Works numbers were 28705-28729 in 1954.

Firebox heating surface included 26 sq (2.42 kg) of arch tubes.

Powerful Mountain Garratt for the light 45-lb/yard (22.5 kg/metre) rail of two SAR branches, Natal's Greytown-Pietermartizburg and Transkei's Amabele-Umtata line. These were among the last steam engines to be ordered for South Africa's principal gauge. As such, they incorporated many of the components found in the earlier GMA class (Locobase 771). These included a round-topped boiler, Walschaert gear actuating piston valves, superheater, and mechanical stoker.

Commonwealth Steel Castings Corporation of Granite City, Illinois provided the one-piece cast steel frame with Franklin spring-loaded wedge horns as well as the castings for the two engine units. All axles turned in roller bearings.

To reduce weight, Henschel reduced both boiler and firebox sizes as well as grate area. Cylinder liners reduced their diameters by 2" (50.8 mm)

Attached to 6810 Imperial gallon (8,190 US gallons, 31,000 litres) auxiliary water tank, thus being described as a "tank-and-tender"..

Ziel and Eagleson (1973) note that this class was "Renowned as heavy haulers that are flogged to the limits of their mechanical endurance." This nth-degree forced power proved a mixed blessing when some of the class were transferred to the Eshowe and Nkwalini branches "They were soon withdrawn from the Eshowe branch, however,", Wikipedia reports, "as a result of their tendency to start fires while climbing the 1 in 30 (3?%) gradients through sugar cane fields."

After just 22 years of service, the entire class sat idle and were withdrawn for scrapping in 1984.

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Class HF (Locobase 13097)

Data from Holland, Volume II (1972), p. 52. Works numbers were 20698-20707 in 1927 and 21052 in 1928.

A "modified Fairlie" designed by the SAR's Colonel Collins arrived on the Natal North Coast and disappointed at first. According to Holland, G Ramsay, mechanical engineer in the SAR's Durban shops, came up with modifications to the blast pipe arrangement. Then its power could be put to good use.

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Class NG.G 16 (Locobase 703)

Data from South African Railways & Harbors 8 - 1941 Locomotive Diagram supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. See also [], last accessed 12 June 2016.

Prairie Garratt originally ordered by Tsumeb Corporation in what was then South West Africa (later Namibia). But the SWA converted all of its rail lines to the Cape Gauge (1,067 mm) and these seven were sold to the SAR before delivery. They were put on the Avontuur as "tank and tender" engines; that is, an NGG16 trailed an auxiliary tender behind the locomotive. Later reassigned to Langkloof, which had a more closely spaced system of water towers, the class dispensed with the tenders.

Years after they left SAR service, three of the class served the Ffestiniog & West Highland Railway in North Wales. As of 2016, 137 and 143 operated during the season, the former in Crimson Lake livery, the latter in Brunswick Green. 143's 2014 overhaul stretched over a year and a half, constituting what Festpedia declared was "the most comprehensive overhaul that a NGG16 has had at the WHR".

Its comprehensive quality illustrates the relatively robust support network for steam locomotive operation available in the 2016 British Isles. Festpedia listed all of the new components installed: "suspension links, springs, horn cheeks, horn keeps, rod end bushes, all of the bushes in the valvegear and pony trucks." Much work on worn components was required, Festpedia, including an"issue that we did not anticipate": fixing the rear frame stretcher.

143 returned to service in May 2016.

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Class NG.G 16 (Locobase 759)

Data from locomotive diagrams published on [] . See also Eryl Crump, "Welsh Highland Railway to restore a 'New' Garratt loco", North Wales Daily Post (29 June 2015) at [], last accessed 12 June 2016; and [], last accessed 12 June 2016.

It's not clear why these Prairie Garratts had a different class number from the NGG 13s. The data show them to have been identical except for slightly reduced weights. [] (July 2002) says the larger cabs were one useful alteration.

Unusual in the Garratt world for having round boilers (vs the square-shouldered Belpaire fireboxes), the first four came from Cockerill led the class with delivery of NG85- NG88 (works 3265-3268) in 1937. Beyer, Peacock soon followed with 109-116 in 1939 (works numbers 6919-6926). After World War II, Beyer's also delivered NG125 - NG 131 (7426-7432) of this class in 1951.

Most withdrawn from service in the 1980s. Three of the class eventually found their ways to the Ffestiniog &West Highlands Railway. Cockerill-built 87 was sold first to North Yorkshire's Robin Hood's Bay project, but was resold to the F&WHR in 2007. Restored between 2006 and 2009, entering service in March 2009. In 2012, the 87's wheels and tires were replaced and the locomotive restored to service in a Colonial Blue livery.

109's F&WHR story is quite different. After its purchase from the Exmoor Steam Railway in 2009, its "fast-track" restoration by apprentices at the London & North Western Railway Company at Crewe was funded by the Peter Waterman Trust. Unfortunately for their plans, funding for the apprenticeship program was canceled and all work stopped. In 2014, "most of the loco" was delivered to F&WHR's Dinas shed for long-term storage.

The 130 was later bought by Gloucestershire's Steam Power Services, which sold the locomotive to Exmoor Steam Railway in late 2014. The Ffestiniog & Welsh Highland Railway ( F&WHR) obtained the engine in mid-2015 when it received the two power units, the boiler cradle, bunker and water tank and sent the boiler off to the boiler works at South Devon Railway and stated that it would build the other bunker and water tank as well as a new cab. At the time of the article, the target date for returning the 130 to service was Spring 2018.

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Class NG.G 16 (Locobase 760)

Data from Gavin Hamilton's excellent compilation of Garratt data posted at [] (6 September 2005); and South African Railways & Harbors 8 - 1941 Locomotive Diagram supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.\). See also Phil Girdlestone & Shaun McMahon, "2ft gauge Little Titans for the Welsh Highland - The 'NGG16s'" published in 1994 and archived at [], last accessed 17 February 2014. Martyn Bane wrote an equally good and comprehensive article on these two Garratts' restoration titled "Alfred County Railway - Garratt 2-6-2+2-6-2 NGG16A Nos. 141 & 155", archived at [] . Prairie Garratt based on the Cockerill-Beyer Peacock design of 1936-1938.

1967-68, the very last steam engines built for South African Railways in South Africa, the last Garratts built anywhere, and probably the last (3894-3901) built by Hunslet. Withdrawn from service in 1985.

Taken in hand by the Sandstone Heritage Trust, the 155 and the earlier 141 were moved to the Alfred County Railway and made over into NGG16As. Adopting many of the innovations pioneered by Livio da Porta, the project involved the following modifications:

Gas Producer Combustion System (Porta's significant redesign of the firebox)

Lempor exhaust with a De Laval blower;

Kordina BETWEEN engine units, not between individual cylinders (the Kordina, named after the Russian engineer who designed it, reduced exhaust back pressure by dividing the exhaust from the cylinders into two);

Master Mechanics self cleaning type spark arrestor specially smoothed for low draught loss. Rounded char breakers were fitted;

Lightweight, mutli-ringed, articulated piston valves;

Valvegear alterations;

Proportional feed mechanical lubrication;

Extended mechanical lubrication, going from a 17 point feed to a 21 point feed;

Roller bearings fitted to the eccentric cranks;

Larger water tank opening to avoid precise "spotting" of the locomotive at water columns.

141 was begun first in February 1988 and rolled out in August 1989. 155 began in March 1990.

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Class NG.G11 (Locobase 744)

Data from Holland II (1972) as amended by an NG 11 diagram hosted on [], accessed 21 May 2006. See also "2-ft Gauge Garratt Locomotives, South African Rys", Locomotive Magazine, Volume 26 (14 February 1920), pp. 24-25; and "Recent 'Garratt' Patent Locomotives", Railway Engineer, Volume 43, No. 5 (May 1922), pp. 184-186. Works number was 5941 in 1918.

These Garratts had been ordered in 1914, but World War I delayed their delivery until 1919. They were pretty fundamental engines, unsuperheated and using slide valves to supply the cylinders. A Belpaire boiler sat between the engine units.

They traversed the ruling 3% grade on the 98-mile Stuartstown section in Natal (later known as the Ixopo branch).

Two of the three were withdrawn from service in 1962.

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Class NG.G11 (Locobase 746)

Data from Holland II (1972) as amended by an NG 11 diagram hosted on [], accessed 21 May 2006; and "South African Railways-Design 02406", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [], et seq, Beyer-Garratt Design No. 02406, pp. 16-17.

Essentially repeats of the Mogul Garratt two-footers from 1920, but with superheaters and piston valves. To an even greater extent than in the larger Garratt locomotives, the boiler and Belpaire firebox and grate dimensions more than matched the demand of four simple-expansion cylinders.

At the time of their introduction, the SAR operated about 1,000 miles (ca. 1,600 km) of 610-mm gauge lines. They began on the Ixopo branch and the 115-mile (185 km) Stuartstown section that featured 35 lb/yard (17.5 kg/metre) rail and a rise in altitude from 171 to 4,617 ft (52.1 to 1,407.3 metres) between Umzinto and Donnybrook The ruling grade climbed at a punishing 3% and the duo negotiated curves as tight at 150 ft.

B-P claimed that the earlier 4-6-2Ts could only manage 90 tons (80.4 long tons) on that stretch, but each Garratt hauled 165 tons (147 long tons) "with the greatest of ease." SAR Annual Reports pronounced their value as "most economical and have reduced train mileage and trainsmen's hours."

When supplanted by larger NGG 16s, the pair migrated to the Estcourt v Weenen branch. NGG 13 2-6-2+2-6-2 engines replaced them in that service and they ended their days on the Avontuur line.

Both withdrawn from service in October 1974; 6200 has been preserved.

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Class NG.G12 (Locobase 754)

Data from Gavin Hamilton's excellent compilation of Garratt data posted at [] . (6 September 2005); and "South African Railways, Design No. 1123", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [],p. 18. FB works numbers were 2506-2507. These Prairie Garratts were sub contracted from Beyer Peacock (BP works #s 6365-6366).

The success of the very-skinny rail NG 11 (Locobase 744) prompted the SAR to order two scaled-down Garratts for the 20 lb/yard (10 kg/metre) light rail of the Upington district. Perhaps because B-P's Garratts almost always used a Belpaire firebox, BP sub-cntracted construction of these round-top boiler engines to Franco-Belge

It's interesting to see the miniature ratios of superheat to combined heating surface, percentage of weight on drivers in these tiny locomotives. Water capacity was divided between front (800 Imp gallons) and rear (200 Imp gall) tanks.

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Class NG.G13 (Locobase 753)

Data from locomotive diagrams published on []

NG49-NG50, and NG77-NG83 were delivered in 1928. Works numbers for these Prairie Garratts were 10549-10551, 10598-10599, and 10629-10635, respectively.

Some of these operated until 1974

[] (a German steam locomotive parts supplier) gives the normal steaming capacity as 5,000 kg/hr. The same site says these were rated as capable of hauling a 165-short ton train up a 2% grade at 25 kph.

[] (accessed 18 May 2006) featured an article on the NGGs by Phil Girdleston & Shaun McMahon published in the November 1994 Railway World. In that account they said that this series set SAR narrow-gauge Garratt design for the next 40 years. The 10 axles spread the weight out along 45 lb/yard (18.75 kg/m) rail. The closest two axles to the center used the Golsdorf system of lateral centering while the pony trucks at the extremes were more converntional.

[] (July 2002) comments that "[t]he cabs were much more cramped than those of the orginal Garratts, and the firemen and their clothes in particular suffered. They took to wearing a shield of leather." The engineer, on the other hand, could escape the heat by "swinging outside the cab." Although no heavier on the axles than the earlier Garratts, these engines pulled a satisfactory load.

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Class NG.G14 (Locobase 757)

Data from Gavin Hamilton's excellent compilation of Garratt data posted at [] . (6 September 2005). See also "South African Class NG G14 2-6-2+2-6-2" in Wikipedia at [], last accessed 15 August 2021. Works number was 10747 in 1930.

Uprated NG.G12s (Locobase 754) with the same boiler and grate, but slightly larger pistons. Always a single-engine class, the G14 joined NG.G12 NG 57 on the Fort Beaufort to Seymour line. Traffic demands on other narrow-gauge lines sometimes required the G14 to take up the slack.

Its days weren't close to over when the Seymour branch gained 18" (457 mm) in gauge. G14 traveled to the Kakamas branch with G12 NG 56 and 57 and served the SAR until 1949, when the Kakamas branch also widened to Cape Gauge. After a short stint in South West Africa, G14 ended its days at the Hunewood Road depot in Port Elizabeth until its retirement in 1952.

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Class U (Locobase 13098)

Data from DF Holland, Volume II (1972), p. 56.

Nicknamed "U-boats" to reflect both the class ID and their German origin, these "Union Garratts" were a hybrid articulated system. The Garratt-type front end held half of the total supply of water and had the pivot of the front engine located ahead of the smokebox. A second long water tank rode under the boiler. The Fairlie back end featured a fixed chassis and a pivoting rear engine under the massive coal bunker.

Holland argues that adopting the long frame of the Fairlie design was intended to simplify mechanical-stoker operation. Alas for the U-boats, the original Duplex mechanical stoker was removed in 1937 and the crew fell to hand-firing because a) after all, the engines were only used for short runs on the Reef, and blockages in the stokers were difficult to clear. "It must have been heavy work," Holland adds sympathetically,"to hand-fire the sixty square feet of grate area."

Holland also comments: "These were large and powerful engines, and had they been built as pure Garratts it is possible they might still have been running today [1972]."

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Class unknown (Locobase 762)

Described in Wiener (1930), pp 212, .214, but no record of works numbers. ILocobase's knowledge of its builder and history remain uncertain. Wiener gives Beyer, Peacock as the builder, but a well-known BP production list compilation shows no 4-6-2+2-6-4 Garratt built by BP for South Africa.]

Preceded the orders to German builders for slightly larger engines.

Wiener noted the mixed construction in which plate frames supported the boiler and bar frames formed the bogies and trucks. Bogies traversed on swing bolsters, trailing trucks used parallel lateral displacement geometry.