Towards 4000hp
Firstly, small up-ratings were performed on the deltic powerunits by adjusting the rpm governed level up 5% and increasing both blower and fuel manifold pressures. This was outside manufatcurer warranty but it is rumoured that there was full consent to this. It lead to a 3650 hp approximate output. However it did result in more TM 'run hot' incidents. At least three were secretly upgraded and perhaps as many as 6 had the 'fiddle' as fitters called it.
In one attempt to take the uprated deltics and their brethren to 110mph while reducing TM overloads, a fourth field diversion circuit was developed and advances learnt from the KV10 regulator application in DP2 were also applied to allow for an improved application of tractive effort and overall top speed. Although the experiment on 55033 was deemed successful, the cost of upgrade was not deemed to represent value for money and woudl take too much down time fromt he by now premium fleet. Deltics were providing top line express services by now not only ont he ECML with it's core 22 allocation, the Midland long distance to leeds and carlisle-settle, Midland direct services to glasgow and edinburgh but also venturing as far a field onto wetern region with the trial of push pull equipment on the Paddington to Bristol and Cardiff route, the traingle via gloucester / birm. Oxford, and the planned forwarding of the Glasgow/edinburgh- SW services from the WCML Their value in service was more than the 10% speed increase envisaged for the potential upgrade.
Concurrently in the mid 1960s a turbo version of the engine ( PU) had been installed as a weapons system-control electircal generator in several leander class frigates in a 12 cylinder version rated at 2000hp. Also 18 and a 24 cylinder variant had been produced. With the aim of reducing maintainence over the 18 in rail application EE/ napiers envisaged a 12 cylinder application at a derating to traction use down to 1850hp. | However the stipulation for type 6 was approximately as follows
- To haul 1000 tonne passenger trains over shap and beattock achieving maximum speeds of 120mph where permitted
- To be able to start a haulted 1000tonne train on the steepest gradients here and on lickey bank
- To decrease Crewe (later preston and lastly carlisle) north running times by 20% i.e. 12 mins faster in the hour.
- To provide a higher level of ETH
- To haul a maximum load of 1200tonnes allowing for a dragged electric loco and a failed diesel loco to the large passenger train.
The prototype, project Dp4, was designed and static component and rolling road tests conducted with the inclusion of similar equipment to be found on the early production D600 ( later to be class 50). The body shell to be chosen was based on the class 50, but with a central train indicator panel on the front end rather than the roof. The chasis required to be 2 m longer but the bogies were basically interchangeable at least 'downwards' to the Dp3s. Stronger armatuers and some other structural modifications were made to the new bogie which were deemed essential for a loco capable of 120mph.
In the end "project dp4" ran a little late as an actual locomotive and was only delivered upon committment to the fleet- this being actually as two pre-production locomotives with all equipment as planned for the fleet and con-currently under delivery from suppliers and assembly from components.
Committing to 4400 HP!
BRB were very close to ordering 50 super-deltics for the WCML north of crewe. These were to be supplemented by the Dp3 ( class 50, D600s) which had shown great promise, especially in pairs over the demanding route with the largest 'royal scot' ans sleeper services. The Dp3s D600s ( later class 50) were more technically advanced than the 'production' D400 DP2s and would in any case replace the last order for Dp2s with the by then prefered flat end layout. The idea was that there would be a release of paired locomotive operations, which had commenced with modified Dp2s and D200s, by utilising single 'Super Deltics'. Further to this aim in going to a far higher horse power than seen before, they would be taking advantage of EE's Newton-le-willows servicing facility during commissioning of such a complex and previously unsurpassed power delivery.
However as mentioned political pressure lead to BRB splitting the order with Brush's Kestrel locomotives. Thus 25 of each were ordered and in the super deltic fleet, six spare power units was judge prudent and fitted in with the revised 'modular repair' plans as detailed below. In actually fact at anyone time Napiers division had 8 power units available at Newton-Le-Willows which could be swapped in a single labour-shift, thus not allowing the PUs to hold back availability. This also allowed them to do spot-investigations on engines upon their first 200 and then 750 hours running to look for potential problems and wear. In general this had worked well in the older deltic fleet and contributed to a high availability for both classes despite their complexity.
A decision was made that all locomotives would initially be stabled at the new crewe diesel shed, the supposedly 'clean' depot removed from steam's incroaches. However, there just was insufficient room to stable loco's and inspect them under roof. Therefore A and B exams and other rectifications or manufacturer investigations were to be held at Newton-le-Willows and Derby in respect of EEs presence in the former and brush's proximity to the latter. This proved to be key in commissioning, fault finding and comprehensive rectification and fault avoidance training in the delivery of these complex locomotives.
Introduction Period
Super deltics, or just "the supers" as they were called, came in as "prototypes" as before for Dp3s, really in fact being pre-production units. This was somewhat risky but in many respects EE were rightly confident in terms of power delivery, performance and reliability between service intervals. In actual fact by the time in 1967 static rolling road trials had been run on "DP4 no.1" there were three sisters nearing completion at Newton-le-Willows. Two were delivered in what was really a pre-prepared commissioned state each with 1000 loco hours and probably more PU hours from the non loco test pans.
These were available for trials in late august-september although EE had had the same priveledge as brush in having ready access to test trains, tachograph coaches and light locomotive runs. At this time there were a further four actually on the tracks under EE private supervision/ownership, and the whole prototyping issue became a bit of a farce. BRB had ordered them on the back of access to the static trials on 55033 with turbo engines and on the good reputation of the Deltics, DP2s and other variants.
By March 1968 the super deltic order was ratified although 8 units were actually ready for service on the 20th of march insitgation of contract for their actual build! A further six were laid down that year, but the DP3 order suffered and given promising service interval and 5400 hp on express services in 1967, with a shorter commissioning time than the super deltics at 6 months rather than the rather luxurious 14 months for the supers.
The push to replace steam had to be balanced with actual full availability of reliable diesel power for express services and WCML area secondary and releif services would utilise the ever growing number of type 2 and 3s made available by the deminishing number of post beeching mixed freights with the move to road haulage.
(BRB were confident to cascade power down the routes to allow for the decimation of the unsuccessful type 2s below 1350hp at least. Type 3 would become the mainstay of semi-fast stopping services and medium distance such as Nw- East England etc, as well as having mixed traffic capacity / availaibilty at shed. Lower powered type 4s would work frieght and longer distance stopping services, and this included the peaks outside MML service and the use of 'permanenlty' paired D200s. General 2500hp plus co-cos would work the typical D1-D399 services on main lines and express freight.)
Super deltics were as mentioned delivered in a tight group of 8 and then a further 6 in 1968 before a gap to allow Newton and RSH(derby) Ltd to finalise the DP3 order, deliver the final D700 order and begin the 'super syphon' project. 14 was probably in hindsight enough given good availability of Kestrels, the planned service interval of the Dp4s and the continuing use of pairs of D600s on the route. However EE had planned to take full advantage of the manufacturer inspection ( D exam) necessitated as an option in the warranty agreement. This meant that depsite a planned service interval at the now trained Crewe Diesel depot and Crewe and Doncaster works, EE could take them out of traffic and secure payment for the remaining 9.
BRB had already scaled down type 4 mixed traffic orders for both the DP3s and the disappointing Brush Type 4s, favouring the introduction of two freight dedicated classes -the class 43 and the class 38 super-syphons which were based on the now proven EE CSVT and Co bogie but at a 10,000 hour service interval. EE were no doubt concerned of the possibility of the invokement of the standard cancellation clause..unwritten..be pals on these cancelled orders today so we can reorganise and order generation 3 tommorrow!
In the end the last two superdeltics were not delivered until1970 and actuall the bill came from GEC Group PLC to BRB.
The Deltic 15TSCM Power Unit
To appease BRB's wish for simpler maintainance and to take advantage of the power gains from turboing, EE/Napiers' division created a 15 cylinder verison of their new beasts. This featured some very advanced features for the time:
- The somewhat archaic Roots blower was replaced with a centrifugal supercharger
- In addition to charged air/water assisted intercooling, the post super turbo feed was 'pre cooled' by a near mirror-image of the exit cool system
- A sequencial centifugal and torque packet fuel pump system delivered fuel to what is now refered to as 'common rail' fuel manifolds with the injectors being operated by a supressor/timer and induction tuned to the vaccuum of the cylinder's stroke.
- The latter system could be used to supress injection of every third stroke of sets of three cylinders. This was utilsed on idle to increase fuel efficiency and on run-down to slow the engine down faster than a pure rpm vaccum demand or timed injection could.
- Oil scavenging and screens for the cranks to reduce burning of oil and deposits in the combustion stroke and exhaust port areas.
The latter was partially successful in reducing the clouds of exhaust so characteristic of the first deltics. The internal oil injection and pressure routing require very clean oil systems and a separate super-clean circuit for the cylinder faces. During running in of new and repaired engines this necessitated the use of centrifugal oil filters which were prone to breaking down or becoming clogged and causing overheats in an engine thus starved of oil.
In general though, not only did turbo charging increase power output significantly, it also helped to ensure complete combustion of fuel in a much larger excess of intercooled air. In practice this meant that the eshaust cloud was reduced in comparison to the deltic on loco's with no faults or internal leaks.
Turboing of course added the defining revving tone over the top of the usual deltic drone while the rather odd 'down shreek and whistle' were a result of fuel injection supression being utilised. This entailed engaing 'supress' in the injectors in short periods, staggered across the cylinders, which meant the engine 'windmilled' for about 30% of the time when shut down to 'notch zero' on the demand handle. Earlier, in a standard fuel pump set up, static test units would sometimes refuse to shut down, the turbo power creating so much pressure that the draw through the fuel injection system overcame the flow regulation and the engines literally had to have their fuel lines cut or run dry to stop them!
Having 'common rail' with rotational fuel compression/feed meant that the system had a far longer maintainance interval than a multi pistion pump or single pump per injector systems. Although more complex internally, it had the feature of being removable as a single component, which alowed for a modular maintainence scheme, where a new or reconditioned unit could be waiting for the time-served unit to be removed. The same modular practice was applied to the inlet manifolds, the downstream fuel manifolds, the final air ducts, the filter areas and the entire super-turbo-cooling assembly.
Servicing the Power Units
This modular approach contributed to a slighlty higher maintenance interval than the original deltics and once fully commissioned the average was over 3500 hours per PU, although some examples in the fleet where notably higher or lower without any real explicability. After commissioning a diagnostic set was run to allow for 'C exam' and further only when indicated by wear and fault' which meant that the maintainance interval was no longer just arbitary but based on keeping the locos in service as long as they were 'looking good'. EE/Napiers were not fully comfortable with the situation but had negotiated only a 2 year manufacturer warranty post the agreed 2 year commissioning period and first F exam, which was in the price. Under this latter period they set a recommendation of no more than 3500hours between full inspection of the PUs.
Towards the very end of the WCML electrifciation programme, which now included Edinburgh via both waverly and Carstairs routes, the depots were accused of 'running the locos into the ground' by avoiding even B exams before one would actually fail in traffic or on idle at the shed! Their aim was clear- locos requiring D exam or higher were to be sent to doncaster works for H exam i.e. heavy general repair that is to say in Works speak- full dismanteling and refurbishment. The worse a state a loco was allowed to get in, the quicker it would be off the depot's costs on the balance sheet.
In the later year or two as wires appeared ever closer to Polmadie and Haymarket, it was the Polmadie-Motherwell shed mafia who were most likely the worst offenders. They never liked the superdeltics or their occiasional older cousins visiations to begin with. The locos were stabled down at crewe to begin with, so if a fault or failure resulted north of carlise the locos were taken in to these sheds on the glasgow services and Haymarket depot on the edinburgh runs. For polmadie and it's heavier brother in repairs, Motherwell depot, this meant recieving engines with hot turbos, hot traction motors, hot blowers, brakes etc etc while at the same time Control having the expectation to turn them around as fast as possible for the premiere services they operated up to 1974. The three depot's had no allocation of locos in the intial 1967-71 period, which meant they could not have spare locos or "hidden" 4000hp beasts as crewe could wangle. Motherwell used their allocation of the less reliable but paired class 50s in the hope of allowing the SuperDeltics to cool down because working around the turbo/exhaust collective area on a super deltic removing any heat sheilds was down right dangerous for fitters when these were fresh from a hard WCML run. Also they hoped in vain to rid them selves of some members of the class 50 allocation which had proved particularily troublesome by patching them up, holding them as reserves for superdeltics and then sending them south while the super's chilled out!
Haymarket however had a less ambivilant relationship with superdeltics and were by 1968 authorised to perform B and partial C exams on the beasts. This was due to their long standing work with the older deltic fleet and allocation of these similar cousin locos. Haymarket were in fact due to recieve an allocation of super's before Polmadie/Motherwell/ Eastfield but a joint training programme for A through D and eventually E exams was set in place at Eastfeild...it having hte best capacity and broadest technical training facilities available in scotland at that time. èven then Glasgow St Rollox works got in on the act. Old edinburgh-glasgow rivalries simmered under the surface but HA really had enough on their hands anyway with the 20 'odrindary' deltics they had for the ECML, NE-SW and inverness routes. Being confronted with the technical compexity of the supers under more than B exam, they were happy to send their failed or failing Super's westward to Dr. Eastfield! In the end they recieved a mere 6 on a floating allocation from Crewe, whilst the "Polmadie" sticker was placed on 12 but half of those were to be stabled at Carlisle and most of the repairs or detailed inspections happened at the other Glasgow area sites or even given pushed slots, Haymarket. Upon full electirfication as far as Carlisle in 1972, the crewe depot allocation was taken as 'stored, servicable, pending reallocation' and thus it became a somewhat uncertain waiting room for those examples which failed in traffic. After this timepoint, there was only really a requirement for between 9 and 12 4000hp plus locos for WCML passengers northwards, and there were some 50 on the books!
However as stated many examples of the 'supers' and the kestrels too were being stored awaiting H exam, redeployment and potential sale to the highest bidder! The actual utilisation stretched of course to mail trains, stranraer services, the perth motor-rail services, the inverness through services and the Carlisle-Aberdeen post and connecting passenger service - the infamous 1S81. Also they were used on sundays under remedial work to the electrified route south of carlisle, either working via settle or under 'dead wires' and even over the WIndscale coast route on a couple of occaisions.
All the above in effect meant that there was a percieved 'need' for a maximum in service at any one time of 29 type 6 locos on the North WCML operations. It was known the first 20 odd deliveries of kestrel/superdeltic wer due H exam and leghnthy mnufacturer assesments. This meant a fairly even run-out of locos whilst the wires crept closer to glasgow and edinburgh.
Once at the interconnector power box at carstairs was swithced on, it meant that loco turn arounds were short enough for the entire type 6allocation to be redeployed. Polmadie were landed with the remaining WCML class 50s to do this short run, whilst superdeltics were kept laterly only at Haymarket and Eastfield for the longer distance through routes discussed already. Kestrels were completely reallocated by late 1973, despite reliability/availability issues with electric locomotives.
There was one chink in the re-allocation armour. Superdeltics had the low enough axel wieght to operate on RA5 routes and from summer 1973 to January 1976 worked both the Fort William sleeper and the Orcadian through service to Thurso/wick. This was in fact a stalking horse for eastfield to keep an allocation of the labout intensive locos North of the border..hence keeping a high level of staffing. But the investment in driver training did not of course lead to a long term allocation and as we will see, their relationship with west scotland at least ended with 1977 when a lone superdeltic worked firstly a west highland sleeper from Mossend, then an inverness special followed by an emergency turn out on a Euston-Stranraer service with the loco actually losing one PU and beign sent light back to crewe.
New trains were found though in the twilight days as the unions at Polmadie realised that they would need to drammatically reduce staffing levels - the new electric locos had proven problematic and the first generation of class 82 and 84 were becoming unreliable. Control allocated both a Glasgow - Leeds and a Glasgow-manchester as diesel throughout despite ever northwards coverage of wires. The leeds service was extended to manchester although this required a loco change at leeds because norht manc' drivers were not to be trained on the supers. One final attempt on 'local' redeployment was to remove the kestrels as by agreement and work all trains north of mossend and edinburgh coming fromt he WCML with super deltics. This also included rerouting one and supplementing one more service to Stranraer via Glasgow central and running the odd '0700 Ayr- glasgow' with a super. All this jockeying in 1974 lead to just the RA5 trains above being covered and the ubiquitous Dp2s or Brush Type 4s working the ingenious new routes. So relegated were the superdeltics that eastfield made a policy of engaging only one engine for these routes. The other engine was literally locked up with a padlock and chain restricting the fuel racks and a 'key box' over the control over-ride panel, with the system being 'off'. It became an open secret that keys for these locos were hidden at different points int he locos so that inspectors at Perth, Fort Bill and Snechie could be informed upon PU nop1 end's failure (as was usual practice) . Churlish drivers egged on by enthusiasts would hunt them out and start up the second unit in the last few months of operation. Unfortunetly for the fleet, when it was known at all depots that work was to cease on them beyond A exam, even Crewe where they concregated, small faults and overheating went unreported and there was a laisez faire complacency developed. Both Eastfield and Haymarket fell out of love with them as soon as redpolyment OFF ScR was the reality and sent even minor failures back whilst running any engine into failure in service to just get rid of them. When an EE rep' came to Scr he systematically inspected locos in service and recommended that 6 of the remaining Glasgow "wanderers" be returned for H exam, whcih they were. At the same time HA failed three of their four and 'got rid' of the final one. This left a lonely loco, 65 006, with no dispatch papers and it worked out it's time to 3450 odd engine hours from Polmadie before the above incidents.
With wage inflation, the demise of much frieght and some passenger traffic and the oil crisis the future for 'thirsty' and labout intensive super deltics did not look particularily rosey and indeed the entire fleet was inactive through much of 1977 and all of 78. In 1976 however, the then GEC company Ltd had decided to buy back it's predecessors offspring and undertake H exam speculatively. However they mid way through closing the deal the death of most diesel hydraulics was brought forward from approximate 1985 run out to 1978. GEC were hence turned around to be invited to tender to service the locos which they agreed to and the fleet were luckily all refurbished by 1980, some few examples re-entering traffic for training and relief operations south of Birmingham in 1979. Had it been later then the class 50 and dp2 redeployment programmes of 1980 would have probably rendered the 25 supers ( 24 actually due to a fire at crewe in 1979) unserviced, non standard white elephants. But the superdeltics went on to provide a further ten years of active service in western region and later private spot hire useage as we will see.
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