Dennis (Denis?) Rock Carling

1906-1992. Dennis Rock Carling was Superintendent of the Rugby Locomotive Testing station. He was a son of Sir Ernest Rock Carling FRCS, an eminent surgeon and specialist in radiology who justified an entry in Oxford Dictionary of National Biography. It is probable that the son's meticulous work on locomotive testing should also have been worthy of an entry in the same  work (the absence of any reference to his son's work shows the weakness of the current ODNB entry, and to an extent the crumbling nature of this national "treasure").

An obituary in the Journal of the SLS (supplied via Phil Atkins) recorded that Dennis Rock Carling was born 29 March 1906 and died 27 September 1992. He gained the Mechanical Sciences Tripos at Trinity Hall, Cambridge in 1928, and went straight to Beyer Peacock for a two year apprenticeship during which time delivered the 1930 Garratts to the LMS. In 1931 he took a sabbatical and visited most of the locomotive builders in Europe before joining the family firm. He moved to the LNER in 1936 as an assistant with the dynamometer car, based at Darlington. During WW2 he worked for the Admiralty in a technical capacity (Riddles in introduction to ILocoE Paper 497 noted that he had worked on magnetic mines and torpedoes during WW2). After the war he rejoined the LNER and owing to the unexpected death of D.W. Sandford was made head of the Rugby Test Plant throughout its steam operations, 1948-1959. Some of his contributions to the discussions on papers presented at meetings of the Newcomen Society are autobiographical and show that he had experience at Hunslet before joining the LNER to work on locomotive testing.

Phil Atkins (e-mail to KPJ) notes that DRC used to come in the NRM Reading Room in early years, a delightful old chap who had a distinctive 'chewy' way of speaking, which the late John Click (who worked with him at Rugby and who died exactly 20 years ago now, coincident with Phil's mother) who also came in, could mimic to a tee (see series of articles by Fred Rich). I am not sure where he served his time, but I think he worked for BP subsequently. I think he was involved with the first three LMS Garratts which it was found when on the hump at Toton the rear coupled wheels came up through the cab floor, so slots and covers were provided on the later 30 production engines. I fancy he had some personal recollections of the Kitson-Still loco (see below). During what proved to be some of his final visits he enquired on behalf of someone in South America the possibility of getting copies of a full set of 9F drawings, possiby with new construction in mind. It was not feasible then, but would be now, if expense was no object! He was the penultimate survivor of Mallard's record run, the last being Norman Newsome. I only wished I'd asked him more about Rugby than I did, amazingly in 1976 the NRM was able to acquire the full archive from the by then derelict Test Plant, from which asbestos sound proofing was hanging from the walls. This included fascinating pre-war correspondence which anticipated testing a P2 there, shades of Vitry. It was designed to handle a 4-8-4 or 2-10-2 if necessary.


4-8-0 tender locomotives. Newton Abbot: David & Charles, 1971.
Not in Ottley, but does include Londonderry & Lough Swilly Railway type. Bibliography lacks full citations to journals, a lack not evident in his Newcomen papers!

Townend, Peter. LNER Pacifics remembered. 2014. Chapter 8
Footplate journeys; observations from the train; in the dynamometer car on the famous Mallard record run, and development of cathode ray indicator with testing on a K3 between Darlington and York, and with an A1 or A3 Pacific between Newcastle and Edinburgh: Gresley showed great interest when such tests coincided with Internationals at Murrayfield. Note on how he missed the transit of Peterborough at 50 mile/h behind the Duchess Pacific during the locomotive exchanges as he had left the train at Grantham. .


Engerth and similar locomotives. Trans. Newcomen Soc., 1985/6, 57, 31-56. Disc. 57-8.
Semmering locomotive: G.W. Carpenter (57) gave some information on the Giesl ejector

Locomotive testing on British Railways. J. Instn Loco. Engrs, 1950, 40, 496-530. Discussion 530-91. (Paper No. 497)
This was a beautifully written paper and surveyed all the testing equipment available at the time: the GWR dynamometer car; the Swindon locomotive testing plant; the ex-North Eastern Railway dynamometer car, and the counter pressure locomotive; the ex-Lancashire & Yorkshire Railway dynamometer car; the LMS gas analysis car (described by P.Lewis-Dale, Institute of Fuel 1936) and the two self-weighing tenders. the "new" LNER dynamometer car fitted with Amsler hydraulic equipment, the "new" LMS dynamometer car and its associated mobile testing unit and special tender. Obviously, the Rugby testing station is also described. .Discussion: Bond (531-3) made reference to Rugby testing station. T. Henry Turner (535-6); Cox (536-7) noted the accuracy of the LNER dynamometer car, and A Reidinger (540-3) refered to D49/2 and class 5 45218 (the later being equipped with special piston valves which gave five different values of lead. The author's reply stated that in both cases the steaming rates had been increased. Tuplin (555-6) proposed a circular test track with a two mile diameter.

Locomotive testing stations: Parts 1 and 2. Trans. Newcomen Soc., 1972, 45, 105-44; 145-82.

A brief history of the counter-pressure brake for steam locomotives. Trans. Newcomen Soc., 1983/4, 55, 10.
Author was involved with fitting system to Beyer-Garratt locomotives supplied to Ecuador and to the Central Railway of Peru, and later was involved in testing the B17 and K3 classes on the LNER using the test locomotive. P.N.D. Porter noted a Railway Magazine article (incomplete citation: 1933 p. 43) by S.R. Yates: notes on Scottish locomotives and railway working wherein it was noted that Jones used the Chatelier system of counter-pressure water braking on his 4-4-0s. Paper includes biographies of several significant engineers not in Marshall.

D.R.  Carling.  Difficult deliveries  Rly. Mag., 1982, 128, 478. 478-80.
Together with Russell Cropper, an erector with Beyer Peacock, travelled with the new Beyer Garratts to the LMS at Derby, completed their erection and introduced them into service and in the process experienced incidents which might have been serious due to the lack of experience by the footplate crews. Cropper had experience of erecting Garratts in Ecuador on the Guayaquil & Quito Railway where conditions were primitive and improvisation was necessary to maintain services.

D.R. Carling.  Foreign locomotives on British rails. Rly Wld, 1977, 38, 358-62.
The Norris 4-2-0 locomotives acquired by the Birmingham & Gloucester Railway and used on the Lickey Incline were also tried on the Grand Junction Railway and on the steeply graded Bolton & Leigh Railway. Sinclair on the Great Eastern Railway obtained locomotives from Schneider of Le Creusot including five 2-2-2 WN 949-53/1866; RN 87-90 and 299. Also 2-4-0 WN 928-37 RN 407-16 plus a slightly larger 2-4-0 exhibited at the Paris Exhibition No. 300 (WN 1079/1867).

D.R. Carling. Foreign locomotives on British rails–2. Rly Wld, 1977, 38, 408-11..
De Glehn compound 4-4-2 purchased by GWR from Société Alsacienne; L class 4-4-0m purchased by SECR from Borsig; Taff Vale Railway six locomotives on order from Habover Locomotive & Machinery Works; Port of London Authority order for six shunters from Hohenzollern just before WW1. Eralier LNWR had ordered tramway locomotives from Krauss. Baldwin standard and narrow gauge locomotives supplied during WW1. Krauss The Bug supplied to Romney Hythe & Dymchurch Rauilway

Carling, D.R. Testing with the counter pressure locomotive. Rly Wld, 1981, 42, 540-2.
Le Chatelier system fitted to B13 No. 761 under Tom Robson the Chief Test Inspector and with the assistance of Percy Dobson on the footplate.. The driving axleboxes were replaced with ones made from solid bronze and adequate lubrication, and large drain cocks and relief valves were fitted. Carling had personal experience on tests on B17 and K3 classes, but not of the earlier D49 tests. Noted that Percy Dobson was expert in controlling slipping. The locomotive was rough and dirty..

Babbage and the dynamometer car presented at Babbage-Faraday Bicentenary Conference - Cambridge, 5-7 July 1991. Trans. Newcomen Soc., 1990, 62, 143-56 (Carling page 145)

Contributions to discussions

Brown, D.C. Counterbalancing and its effects on the locomotives and the bridges. J, Instn Loco. Engrs., 1938, 28, 121. (Paper No. 381)
With regard to the shuttling of engines, there was no doubt that at times that could be extraordinarily unpleasant to passengers, quite apart from any effect which it mignt have on the engine itseli in the way of increased maintenance. It had occurred to him that that might be due to synchronism in the natural period of vibration of the buffer and drawhar springs as loaded with the masses of the engine at one end and the train, or part of it, at the other, and the speed rotation of the engine wheels and, though it did not come directly under the subject of counterbalancing, it was a matter which might be looked into on passenger engines. He had been nearly shaken out of his seat in the first coach of a suburban train travelling fast with a tank engine.
He said there was no mention in the Paper of any other means of balancing reciprocating masses than by weights on the wheels. Some recent two-cylinder French engines were fitted with Cossart valve gear, and the driving mechanism was so arranged that the return cranks were at 180° to the main driving cranks, and the designer had deliberately put heavy weights on the end of what we should normally call the eccentric rod at the end remote from the return crank, so that there is a heavy mass reciprocating in exact anti-phase to the corresponding piston and crosshead and nearly in the same line. He asked if the Author considered that that would be a valuable method of achieving balancing of the reciprocating forces without any corresponding hammer-blow The whole gear was described in The Locomotive for April and May, 1933, the latter article containing the part relative to counterbalancing. He also enquired if the Author could give an opinion as to the practicability of balancing a four-cylinder compound locomotive in accordance with marine practice on the Yarrow-Schlick-Tweedie system, bv which all primary forces and couples could be eliminated, but which required uneven crank spacing
who refered to shuttling and mentioned the Cossart valve gear which had been described in Loco. Rly Carr. Rev., 1933 April/May

Hills, R.L. The origins of the Garratt locomotive. Trans Newcomen Soc., 1979, 51, 175-89. Discussion page 192.
It would be interesting to know if the sketch of the cab-in-front locomotive in Garratt's scrap-book was made before or after the appearance of Planchar's Italian 4-6-0 Mucca, which was similarly arranged, and details of which were pubIished in England ear1y in 1903. There was also an Italian 0-10-0 type arranged in the same way. The Garratt was inherently more stable than a Fairlie. yet one of the Fairlies of the Mexican Railway once descended the whole length of the Maltrata incline. with no crew abroad, at a speed that must have exceeded 60 m.p.h.; the bogies may have hunted a lot, but they did not derail. On the other hand the very good riding of the Tasmanian. express Garratts was the cause of a derailment due to excessive speed on a sharp curve, alleged to have been due to the driver not realising how fast he was going. It was said, when I was at Beyer, Peacock & Co., that this accident spoiled the Australian market for Garratts for many yeats. The Author mentions a 2 ft. 6 in. gauge system in New South Wales; should this not be Victoria? All railways in New South Wales were legally bound to be of standard gauge, excepting the two lines connecting only with the Victorian 5 ft. 3 in. gauge and the Broken Hill 3 ft. 6 in. system connecting with South Australia, which was legally a tramway. It was the long boiler tubes of other locomotives that made necessary an excessive draught in the smokebox in order to obtain the requisite draught in the firebox. One reason. for the Garratt not being adopted in the U.S.A. was that the Garratt was a tank engine and, except for some suburban: passenger traffic, tank engines did not suit Ameriean operating conditions, which latterly required very luge supplies of fuel and water. [We havc since learned that the prototype of the Italian Mucca locomotive was shown at the Paris Exhibition in 1900 and a full description appeared in The Engineer in 1901. Ed.], Author's Note: The title for the 2 ft. 6 in. Garratt appears on the scheme drawing as '"New South Wales Public Works Department" but this is an the information given and nothing more could be discovered about it.

Hughes, J.O.P. The design and development of a gas turbine locomotive. J. Instn Loco Engrs., 1962, 52, 224.(Paper No. 633)
it gave him great pleasure to be able to contribute to the discussion, because the tests, which the Author had described, at the Rugby Locomotive Testing Station were carried out when he was Superintending Engineer there. Carling believed that the use of the locomotive testing station to give information at that stage in the design and development of the locomotive was of paramount importance to its ultimate success. No doubt many earlier projects involving new types of locomotives came to no good because such facilities were not, or were not made, available. Quite minor troubles encountered when working on the line could lead to extremely expensive failures ; a lubrication failure could destroy a great deal of machinery, if it was not quickly observed and the locomotive promptly stopped. Also an over-estimation of the capabilities of a locomotive could cause it to be put on unsuitable duties. One case which came to mind concerned the Kitson-Still locomotive, which was over optimistically rated. It was given duties to do that were outside the scope of the diesel portion of the machinery with such steam power as could be derived from waste heat alone, and burning diesel oil in a steam boiler to obtain supplementary steam was very expensive if used for too high a proportion of the total time. That largely put the machine out of court, coupled with the unfortunate fact that the builders ran out of money!
He believed that a Test Plant could still be of great value in this way, even for existing forms of traction, when new developments less revolutionary than those described in the Paper were involved. The Author had mentioned that his locomotive had the possibility of using cheaper fuel. Would he state whether that was still only a possibility or whether it was now a probability?
He thought that there must be a number of railways abroad where such a locomotive would have a very fair chance of success, in particular any lines where operating methods and traffic requirements permitted the locomotive to be suitably loaded so that its fuel costs per unit of work done would compare well with that of other types of locomotive and where its inherent characteristics could be made use of, as listed by the Author in the Paper. It should be noted that for sustained power output at the drawbar this locomotive was outclassed by only one type, other than straight electrics, in this country. It has the power to move the traffic but only further running would show if it has the necessary stamina. Personally he thought that it would have, and hoped it would be given the chance to show it.

Lomonossoff, G.V. and Lomonossoff, G. Condensing locomotives. Proc. Instn Mech Engrs, 1945, 152,  275-88. Disc.: 289-303.
The authors stated that the Maffei locomotive had been the most successful of all turbo-locomotives. Was that intended to refer only to turbo-condensing locomotives? As far as he was aware, the only turbine-driven locomotive for which the users had given a repeat order was the 2-8-0 non-condensing type of the Grangesberg railway in Sweden.
The resuIts obtained with condensing locomotives in Russia were most illuminating, and showed that the use of condensate as boiler feed resulted in lower maintenance and fuel costs. It was to be expected that performance would deteriorate less as the period since the last shopping increased. How did the reliability of classes SO and SOk compare?

Pyne, A. The Kitson-Still locomotive. Trans. Newcomen Soc., 1970, 43, 53-62. Discussion page 63.
Carling's first contact with the Kitson-Still locomotive was as a student doing his first workshop training, not at Kitsons but at Hunslets, next door; but he was privileged to visit Kitsons and aauaIly to drill one of those 0.012 in. holes in an experimental fuel injector. Ten years later he joined the staff or the LN.E.R. testing section and worked in the dynamometer car. Tests of the Kitson-Still were over, but he not only examined some of the test records, but also talked with the men who were involved with the tests. In his own opinion the tests, at least with goods trains, were unfortunately conducted. The Kitson-Still was fated just a little optimistical1y in relation to the L.N.E.R. 0-6-0 goods engines. It cou1d not haul quite the normal load of those engines over the more severe parts of the line on internal combustion alone, nor even with occasional help from the steam boiler. The burner had to be kept on for too great a proportion of the time when as well as during the long standing periods which occurred in service. In his opinion tests should aIso have been made with a slightly uduced load, which could have been handled with little, if any, use of the burner except for starting. Diesel oil was a very expensive boiler fuel But the fate of rhe project was really settled by the state of depression of world trade in those slump years. Railways all over the world were having difticu1ty in making ends meet, and, with very few exceptions, were in no position to risk money on experimental locomotives. Indeed, they ordered so few locomotives of well tried kinds that many locomotive builders went out of business and many others only just weathered the storm. By the time things became better Kitsons had ceased to build locomotives. This was a sad end to a venture that deserved better.

Riemsdijk, J.T. van. The compound locomotive. Part 2, 1901-1921. Trans Newcomen Soc., 1970, 44, 73-98.
Initial comment in response to Carpenter's comments about the "Gelsa" locomotives for Brazil: these were newly built engines to Chapelon's designs, ninety in all, but at the users request, all simple-expansion. Chapelon also designed the series of standardised compounds for the S.N.C.F., the building of which was authorised and, for one type actually Commenced, before being cancelled due to a change of higher policy. Also confirmed that the Bavarian 4-4-4 compound high-speed locomotive was unique. He also noted that the articulated locomotive that so considerably out-performed the South African Mallet compound was a Garratt, not a Beyer-Garratt, that latter appellation not coming into use until 8 or 9 years later when he himself was at Gorton Foundry.

T. Robson. Counter pressure method of testing locomotives. J. Instn Loco. Engrs, 1943, 33, Paper 441 pp. 202
A point of considerable difficulty in dealing with the test equipment was that the locomotive under test was housed in the ordinary engine sheds, and all the apparatus hac! to be designed with that fact in mind, because one never knew when one's carefully made indicator was going to receive a clout from the shovel of ~ passing fireman, or when some similar mishap would occur to other apparatus. All delicate equipment had to be dismantled every night. When he had the honour of accompanying the author to France they had been greatly impressed by the fact that for certain tests which were being done there a large electric express locomotive was placed permanently at the service of the experimental section, which was provided with adequate accommodation for it, and only at times of great traffic activity was it returned to the Traffic Department, as a favour. There could no doubt that an improvement in the conditions under which tests were carried out would greatly simplify the apparatus used, and probably the value of the results obtained would far outweigh the cost of providing the equipment.

Skeat, W.O. The Great Eastern Railways "1500 Class" locomotives. Trans Newcomen Soc., 1970, 42, 75-97. Disc.: 97-106.
During his days on the London and North Eastern Railway he had ridden on, and fired on, the Great Eastern l500s in 1937, and one of his recollections was that they were by far the most comfortablc-riding engines with coupled wheels under the cab that he had ever been on. Doubtless one of these engines on which he had ridden, because it was one of those kept for Royal trains, was in the very best condition; nevertheless the impression was strong. The duties were not heavy-they were running between Cambridge and King's Cross — but the memory remained as a very pleasant one.

Other pertinent material

Rich, Fred. "You'll go to jail, young man...". Part 1. Steam Wld, 2005, (215) 8-14.
Rich started work at Rugby in 1957 when the plant was past its prime. Nevertheless, there are interesting illustrations and rewarding reminiscences about D.R. Carling, the Superintendent and about Horace Clarence Ockwell, his Deputy. Ockwell appears to have been mildly eccentric. Tommy Cadzow (1903-77), a Scot, was the chemist. These senior members of staff are portrayed in a group photograph (taken by J.M. Jarvis) with Robin Johnson, John McCann (a sometime contributor to Steam World) and George Podmore. Ron Pocklington was in charge of the Farnborough indicator. John Click (1926-88) was the footplate observer until 1956 when Rich tookover. Notes that Eric Nutty was Ell's footplate guru. Alleges that on road testing Derby "couldn't hold a candle to Sammy Ell" at Swindon, although Swindon lacked a Farnborough Indicator. and did not indicate every cylinder. Ockwell stated that "we will never outshine Sammy Ell becase he doesn't set out to prove himself wrong!". Swindon was integrated and coherent. On 26 November 1957 Carling met Chapelon in London where Chapelon congratulated Carling concerning the tests of the Crosti boiler: "These tests of yours are the most accurate and consistent that I've ever seen". Chapelon had been called in to adjudicate between Crosti and British Railways over the savings which had been expected from the use of the Crosti boiler. The Heenen & Froude dynamometers were hydraulic. The article also describes the testing of the gas turbine locomotive GT3 and its designer J.O.P. Hughes and George Howe his test engineer.

Rich, Fred. "You'll go to jail, young man...". Part 4. 36-43.
The final part of this interesting series states how Fred Rich gathered information through his footplate riding mainly on the WCML and the Great Central route on what might be termed the ergonomics of footplate design: this was eventually published as Paper 589 in the J. Instn Loco. Engrs. Carling was very supportive of this work, but Ockwell banned any further footplate journeys (by withdraweing access to the footplate pass). During these footplate journeys Rich found the B1 class to be extremely rough and a vast contrast from the smooth-running Hall class. Although he described a footplate journey on a down journey via High Wycombe with a V2, the only real observation was that the class tended to produce a lot of smoke, and in the case of this particular locomotive it was necesary to run with the firedoor open.  Illus.: group photograph to mark Tom Cadzow's departure for Stratford: also present: John Hicks, Garry Hibberd, Brian Hughes, Alan Betts, John Tierney, Charles Paterson, Denys Twine, Carling, Ockwell, Ron Pocklington (Farnborough indicator), Dick Grant, Dick Wilkinson, Bill Lucas, Norman Norton, Tom Potter, Driver Charlie Drouet and Fireman John Beck.

John Tidmarsh (Steam Wld, 2005 (218) p. 20) adds a considerable amount: "Dennis Carling was a delightful character and became a good friend when I succeeded John Gardam as ORE Conseiller Technique in 1965. His wealth of experience in steam locomotive design and testing was legendary. Writer particularly enjoyed listening to the fascinating stories of his railway life over a good evening meal after a long ORE meeting during our many journeys around Europe. He was extremely well-travelled and had met many prominent people in the steam world - such as Andre Chapelon, mentioned by Fred Rich - and right back to the great Russian testing engineer Lomonossoff in the early 1930s. He was also present in the dynamometer car during Mallard's 126mph dash in 1938. He had a lovely old-English charm and, as Fred mentions, always addressed you simply by your surname. Incidentally he was also seconded to the ORE organisation at Utrecht as a Conseiller Technique in October 1959, being succeeded by John Gardam in January 1962."


Mechanical stokers in Europe. Locomotive Mag., 1931, 37, 107


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