Refurbed HSTs. A folly?

[Hatfield Shed]

A little harsh on the locomotive application of the steam turbine? The Swedish Railways made a success of them, largely due to the presence there of F. Ljungstrom, who was a world class engineer and contributed much to general steam turbine plant development, in addition to significant work in other fields. It was this that led the LMS to give the steam turbine loco a whirl; but lacking the supporting industrial infrastructure that was available in Sweden, maintenance was the weakness.

[Mickey]

It was this that led the LMS to give the steam turbine loco a whirl; but lacking the supporting industrial infrastructure that was available in Sweden, maintenance was the weakness.

Sorry to go way off the topic but that LMS steam turbine-driven loco looked impressive as all LMS steam express passenger locos did but without the need for outside valve gear on the driving wheels it looked rather odd (to me) I thought?. Anyway, the loco was involved in the Harrow crash of 1952 and was scrapped.

Getting back on topic I suppose the HSTs had their following amongst railway enthusiasts and trainspotters but I can't say I was all that struck on them although I thought they looked better in their original mid-1970s British Rail livery rather than their 1990s/2000s livery.

[Hatfield Shed]

The HST worked and the ride was decent. Looked their smartest in the all over GNER blue in my opinion: but I never rode them in that form because we had the excellent '225' 91+mk4 electric sets by then. Possibly the last good express passenger train equipment for the UK, all downhill from now onwards with very utilitarian equipment to rattle you swiftly between London and Edinburgh. (I realise there are other UK routes, but only one is truly significant.)

[rockinjohn]

Ref: the "Downunder"HST retitled "XPT" quite a lot of mods.were made before entering service in 1982 (approx).engine downrated/extra cooling &air filters for obvious reasons, boogies were "tuned" for @ the time, (maybe now also) to cope with v. indifferent track conditions, quite reliable in the main or maybe they just didn't announce the failures! &reaching 2000 before the newer as fitted in the UK also, improved Paxman Engine.With the comments on Gas Turbines, I think the main reason for not being adopted in the UK was that the turbines needed to run on full power for fair distances, their true worth appearing on the long drags to be worthwhile, Union Pacific in the USA worked theirs quite hard with little trouble for many years with progressive runs of loco build,I suppose our Lickey/Shap or Dainton banks just not long enough& not needing to change locos to benefit from a fleet of gas turbines.

[Hatfield Shed]

...With the comments on Gas Turbines, I think the main reason for not being adopted in the UK was that the turbines needed to run on full power for fair distances, their true worth appearing on the long drags to be worthwhile, Union Pacific in the USA worked theirs quite hard with little trouble for many years with progressive runs of loco build,I suppose our Lickey/Shap or Dainton banks just not long enough& not needing to change locos to benefit from a fleet of gas turbines.

Nail, Head, Hit. Early gas turbines were not very fuel efficient, and only found their way onto fast combat aircraft for the performance advantage over piston-prop. The problem was that the lowest throttle setting at which the early engines would keep running still yielded near 50% of full power. (There's a wondrous story of Chuck Yeager overcoming the resulting 'it won't slow down' problem on the first test flight of the B47, on which Boeing's design staff had omitted to fit drag brakes.)

The two GW originated gas turbine locos burned away their power turbine blades, casings and exhausts because insufficient energy was being extracted for propulsion purposes which would have cooled the gas stream and thus prolonged hot component life. Had the GW had a thermodynamicist in their employ, she might have suggested setting the train brakes to drag on level and nearly so route sections which would have eased the problem by requiring more power from the GT locos. Cast iron brake blocks would be cheaper and ubiquitously available to the fitters, as compared to the late 1940's unobtainium used in the GT components, and the few specialised staff to fit the parts...

[richard]

Okay - I hadn't heard of Ljungstom. Looked those locos up. No condensor?

As for gas turbines, I also skipped the UP engines - on the face of it another success: 50+ locos built and operated for 22 years. However, their fuel consumption was roughly double compared to similar contemporary consists. Not exactly a big success!

[Hatfield Shed]

Okay - I hadn't heard of Ljungstom. Looked those locos up. No condensor?

As for gas turbines, I also skipped the UP engines - on the face of it another success: 50+ locos built and operated for 22 years. However, their fuel consumption was roughly double compared to similar contemporary consists. Not exactly a big success!

Fitting a condensor to a steam loco was difficult due to bulk. TTBoMK only in South Africa was this successfully employed on otherwise conventional steam locos for water recovery, toward the end of steam power.

The UP gas turbines were a useful idea when designed. More thermally efficient than UP's big coal fired steamers - well that wasn't diffcult! - but well below diesel performance. However the GT loco benefitted from the much higher specific power of a gas turbine compared to the other two, resulting in more power output per unit weight in the complete loco; and then the killer advantage, it burned near worthless 'Bunker' fuel which (vile stuff) was a waste product of contemporary oil refining, so the energy consumed came at a much lower unit cost then diesel fuel. However this advantage was progressively eroded by the invention and ongoing development of catalytic cracking, which enabled refineries to break the large molecules in what had previously been waste product into lighter fractions which were saleable and in high demand. and that killed the low energy cost advantage.

Oh well, seemed like a good idea when proposed...

[sandwhich]

It would seem that Great Western who made a big thing out of the use of refurbed HSTs are looking for a way out of using them because of increasing maintenance costs with "surplus" IEP units becoming available to replace some where possible. They admit it is a plan to gradually replace them but not overnight. There will be a surplus of 47 Class 221/222 units which be coming off lease from West Coast and East Midlands in the next couple of years, some will go to Cross Country which will no doubt see off their small fleet of HSTs, could the rest go to Scotland, only time will tell.

[Hatfield Shed]

Not too surprising in the wake of the RAIB report on the fatal derailment at Carmont (Stonehaven) in 2020.Quietly damning of the mk3's crashworthiness against current standards, it reads to me as 'check the fleet for these deficiencies, and condemn them'.

[sandwhich]

I give 3-4 years for the franchised leased HSTs to become history.

[Mickey]

Been watching several DVDs of mainly HSTs working on the Midland mainline between 1982-1987 after they replaced the class 45 'Peaks' on top link diagrams when they were still working under the then existing mixture of semaphore and colour light signalling while travelling through the 'Leicester gap' between Irchester South box and Loughborough box and it's definitely a case of the 'sweet n sour' complementary effect of old and new working side by side that actually looks pretty good strangely?. Apparently, the HSTs were limited to 100 mph on the Midland mainline unless the driver had a secondman with him in the leading driving cab at the same time.

Michael A. Vann's hardback book 'The Leicester Gap' The last semaphore signalling on the Midland mainline 1981-1987 is not connected with the DVDs but complements watching these DVDs very well.