Were HST Power Cars Really Class 43?

[Barclay]

I hope some in the know will forgive what may seem a silly question, but I often see reference to the IC-125 power cars as class 43. Now when I was a young enthusiast they were classed as a unit, classes 253 or 254, and appeared as such in the Ian Allen books. Each power car had a running number of course, 43xxx, but it was just that, like a coach number, not 43 xxx, if you see what I mean?

 

My other reason to query it is that there were already class 43, some of the Warships, weren't there? I appreciate these were long gone, but I'm not aware of any other case of a class designation being re-used.

 

So - were they really class 43 all along? Did they become class 43 as it became obvious that it was not efficient to always keep the same combinations together, and abandoned, I believe, the idea of naming them in pairs, to avoid silly combinations? Or is it just a modern affectation that the railways never used?

 

It's not very important of course, but I'd appreciate some insight!

[Jeremy Cumberland]

The prototype power cars were class 41, with numbers 41 001 and 41 002, before the set became DEMU class 252. The power cars were then renumbered in the carriage number series as W43000 and W43001.

 

With the production HSTs, the situation was reversed. When built, they were DEMU classes 253 and 254. However, it became common to swap power cars around, so sometime in the mid-1980s, the 253/254 designations were abandoned and the power cars reclassified as class 43, making fortuitous use of their existing numbers. The lowest number was 43 002.

 

Edited November 7, 2023 by Jeremy Cumberland

[russ p]

The rule book used to refer to HSTs as class 253 and 254 trains. It seems to be a later thing where power cars were referred to  as class 43 locomotives . However the prototype ones were referred to class 41 locomotives 

[ikcdab]

It is interesting how ones memory plays tricks.  I have dug out my old combined volumes.

1974: shows a class 41, the prototype HST set. No class 43.

I don't have 1975, but my 1976 edition is showing them as 252 (the original class 41) and 253. No mention of class 43 anywhere.

Despite that, in my day, they were universally referred to as HST. 

[Mike_Walker]

They most certainly were Class 43s throughout their lives.  Classes 253 and 254 were the numbers given to the complete sets and were originally applied to the power car noses but this was soon abandoned when it became obvious that the power car maintenance cycles differed widely from that of the trailers and therefore keeping them together was inefficient.  Likewise, attempts at keeping complete sets of trailers together didn't always work.   Laira for example would usually reform at least one set a day to switch out a defective vehicle and replace with a spare; hence the the regular sighting of odd liveries in sets during times of livery transition.

 

Classes 253 and 254 continued to be used in operating publications such as the Sectional Appendix up to the present as a convenient way of identifying the different length sets and where they could or could not be used as an example.  GWR refers to its short "Castle" sets as Class 255 although I'm not too sure how "official" that is.

 

Other class numbers have been reused.  The D600 series Warships were, on paper, allocated Class 41 although their demise in December 1968 coincided with the introduction of the TOPS classifications and Class 41 was used for the prototype HST power cars 41001 and 41002.  These later became W43000 and W43001 in the carriage series (pre-TOPS for those) which were then followed by the production power cars starting at W43002.  When the power cars became regarded as independent locomotives in their own right they became Class 43.  And, of course much in our thoughts at the moment, the Southern "Booster" locos were Class 70 now reused for the Freightliner and Colas GE locomotives.

 

[Mike_Walker]

I also understand that the Rolling Stock Library that manages the allocation of class and vehicle numbers operates a moratorium system that permits reuse of numbers but only after a set dormant period.

[Michael Hodgson]

Class 43 was indeed the Warship D800 - D870 but they were all withdrawn by the end of 1971and scrapped shortly afterwards.  This was because of a decision to standardise on diesel electric rather than diesel hydraulic, although the Hymeks lasted a few yeras longer.

 

It is debateable whether HST "power cars" are locos at each end of a train of Mark  III stock or merely part of a unit (253 class), and they were allocated class 43, which was by then vacant.  Calling them DMUs is perhaps misleading as they didn't work in multiple.

[Jeremy Cumberland]

The power cars were not originally class 43. The power car numbers W43xxx and later E43xxx and Sc43xxx were in the carriage number series, and there wasn't a locomotive class 43 (the Warships having long been withdrawn)

 

The separate carriage number series was discontinued in about 1983, and carriages were added to TOPS in the same number sequence as locomotives. Spotters of that era will be familiar with this from the renumbering of DMU driving trailers from 56xxx to 54xxx, to avoid duplication with class 56 locomotives. From this point onwards, I suppose it made little difference whether the power cars were carriages in the 43xxx number sequence or class 43 locomotives. I have no idea when class 43 data panels started appearing, but you won't find them on any photos from the 1970s.

[Cruachan]

Based on this previous thread, the production power cars were retrospectively reclassified as class 43 locomotives in around 1989:

HSTs - which TOPS Class? - UK Prototype Questions - RMweb

 

As noted above, TOPS classifications can be reused after a certain number of years have elapsed. The other TOPS loco class to be reused is class 70, and the BR shipping range, class 99, is shortly to be reused for a new Co-Co bi-mode locomotive.

Edited November 8, 2023 by Cruachan

[Wickham Green too]

9 minutes ago, Jeremy Cumberland said:

... renumbering of DMU driving trailers from 56xxx to 54xxx, to avoid duplication with class 56 locomotives. ...

Oddly, two of the operational Power Cars of the preserved Hastings Diesel unit are now numbered 60116/118 - rather than 600016/18 - so as not to clash with class 60 diesels - but they've not been put in a different sequence ( 61016/18 for instance ). Power Car 60000 doesn't clash with a diesel so retains its original number !

[pete_mcfarlane]

59 minutes ago, Michael Hodgson said:

Class 43 was indeed the Warship D800 - D870 but they were all withdrawn by the end of 1971and scrapped shortly afterwards.  This was because of a decision to standardise on diesel electric rather than diesel hydraulic, although the Hymeks lasted a few yeras longer.

Only the NBL ones. The Swindon built Warships were class 42. There were enough difference between them to warrant separate classes. 

[Steamport Southport]

2 hours ago, Michael Hodgson said:

Class 43 was indeed the Warship D800 - D870 but they were all withdrawn by the end of 1971and scrapped shortly afterwards.  This was because of a decision to standardise on diesel electric rather than diesel hydraulic, although the Hymeks lasted a few yeras longer.

 

It is debateable whether HST "power cars" are locos at each end of a train of Mark  III stock or merely part of a unit (253 class), and they were allocated class 43, which was by then vacant.  Calling them DMUs is perhaps misleading as they didn't work in multiple.

 

They stopped being classed as units in the mid 1980s when they were no longer used as fixed sets as it was next to impossible to keep them as sets due to the fact that if one car developed a problem then the whole train was then out of use. Fine doing it with a DMU or EMU, but not one of your express passenger trains,

 

That was about the time they got the Class 43 designation.

 

 

Jason

[The Stationmaster]

3 hours ago, Mike_Walker said:

They most certainly were Class 43s throughout their lives.  Classes 253 and 254 were the numbers given to the complete sets and were originally applied to the power car noses but this was soon abandoned when it became obvious that the power car maintenance cycles differed widely from that of the trailers and therefore keeping them together was inefficient.  Likewise, attempts at keeping complete sets of trailers together didn't always work.   Laira for example would usually reform at least one set a day to switch out a defective vehicle and replace with a spare; hence the the regular sighting of odd liveries in sets during times of livery transition.

 

Classes 253 and 254 continued to be used in operating publications such as the Sectional Appendix up to the present as a convenient way of identifying the different length sets and where they could or could not be used as an example.  GWR refers to its short "Castle" sets as Class 255 although I'm not too sure how "official" that is.

 

Other class numbers have been reused.  The D600 series Warships were, on paper, allocated Class 41 although their demise in December 1968 coincided with the introduction of the TOPS classifications and Class 41 was used for the prototype HST power cars 41001 and 41002.  These later became W43000 and W43001 in the carriage series (pre-TOPS for those) which were then followed by the production power cars starting at W43002.  When the power cars became regarded as independent locomotives in their own right they became Class 43.  And, of course much in our thoughts at the moment, the Southern "Booster" locos were Class 70 now reused for the Freightliner and Colas GE locomotives.

 

One point Mike - and it is one of my hobby horses so apologies for going here yet again.    The loco classification system, e.g. Class 41, had nothing whatsoever to do with TOPs and was created well before BR even thought about buying TOPS.  Don't forget the standardised class numbering system first appeared in traffic use in connection with the new Freight Train Loads Calculation System from mid 1968 and at that time class data panels began to gradually appear on locos from that time.

 

The first handful of TOPS Trial Sites were commissioned in mid-late 1972 followed by more in early 1973 trialling different local terminal kit and other technological advances; national cutover was intended to start in mid-late 1973.  TOPS software had to be re-written to accommodate the BR class numbering system when it was used as part of the running number.  

 

It is possible - although seemingly has never been stated - that TOPS project money might at least have allowed fulfillment of an earlier ambition to renumber locos  locos using  the standardised Class numbers as the basis of running numbers (I believe from something I was told by a very senior BR traction enginee, well before TOPS appeared, that such an ambition dated from even before 1968).  But the class numbers had nothing otherwise to do with TOPS and TOPS was perfectly happy to accept existing running numbers because that was what its original US software was designed to do.

Edited November 7, 2023 by The Stationmaster

[Halvarras]

Oddly enough I was pondering this same point just a couple of days ago (the things you think about while cleaning your teeth!) The 'Blue Pullman' sets lasted into 1973, long enough to be classified 251 under TOPS - the power cars definitely carried carriage series numbers with W prefix and at the end they got swapped around so MU-fitted/non-MU-fitted combinations could be seen towards the end. I concluded that the difference between these and the HSTs was of course the full implementation of TOPS, which the former ducked. The reasons given above for regarding the HST PCs as locomotives for maintenance reasons must be correct - the Class 43 designation becoming vacant following the demise of the NBL-built D833-65 Warships and the numbering of the PCs as 43xxx was either a fortunate coincidence or a supreme piece of forward planning by somebody in BR who saw the problem of keeping power cars together coming at some point. I'm inclined to think the former (🥴), a lucky coincidence bolstered by the power output of the Warship and PC being the same meaning the positioning on the TOPS loco power output table was spot-on.

 

3 hours ago, Mike_Walker said:

GWR refers to its short "Castle" sets as Class 255 although I'm not too sure how "official" that is.

 

I reckon it's official Mike as it's cast in alloy on every PC nameplate featuring a castle 😉!

[2251]

3 hours ago, Mike_Walker said:

I also understand that the Rolling Stock Library that manages the allocation of class and vehicle numbers operates a moratorium system that permits reuse of numbers but only after a set dormant period.

 

It is pure pedantry on my part, but should be noted that the RSL no longer exists. It has been replaced by the R2 database, which resulted from the merger of the RSL and RAVERS.  

[Peter Kazmierczak]

Here's my take on it, off the top of my head...
 

The High Speed Diesel Train (HSDT) was a railway engineering initiative to counter the aircraft engineering of the APT. The result is history...

The prototype HST (as the HSDT was relabelled) comprised a pair of locomotives between a set of Mk III (they tended to use Roman numerals then) coaches. It wasn't regarded as a unit; rather coaches between a pair of locos - much like the Edinburgh - Glasgow push-pulls of 1971. 

 

The Mk III were to be numbered in the normal coaching stock series of 32xx and 58xx - hence the gap in numbering in the Mk2e series. Soon it was decided to number them in a new coaching stock series, the familiar 10xxx, 11xxx and 12xxx series.

The two prototype locos were numbered 41001/2 in the loco series. 

Before the prototype HST entered service on the WR in May 1975, it was reclassified as a unit with the set number 252001. This followed on from the Blue Pullmans being considered as class 251.The class 41 locos were renumbered in a new coaching stock series 43xxx, with the coaches becoming trailers 40xxx, 41xxx and so on.

Come the production HSTs, the WR sets became class 253 and the East Coast ones class 254. The powered vehicles being classified as Driving Motor Brakes (DMB), or Driving Motors (DM) if they lacked guard's accommodation following the introduction of the TGS. These designations appeared on the end data panels of the vehicles.

So were the production HST power unit vehicles considered as locos? The idea of HST sets remaining static was very short-lived, with changes made right from the first days in service. Sometime in the 1980s the end data panels appeared with Class 43 on them, rather than DMB/DM. So was this when they were officially considered as locomotives again?

What I do know is that Derby Loco Works (who overhauled these vehicles), referred to them as power cars.

[34theletterbetweenB&D]

4 minutes ago, Peter Kazmierczak said:

So were the production HST power unit vehicles considered as locos?

There's a photo posted recently on this site showing a pair moving freight stock. So whatever they were before, they are locos now.

[Wheatley]

This is one of those things where enthusiasts try to classify or define or otherwise codify something which the actual railway either didn't, or did inconsistently, or did and then changed its mind. They were allocated set numbers in the 253/254xxx DMU series with the traction units numbered in the 43xxx series until somebody with a sufficiently large hat (or a sufficiently august committee behind them) decided that it made more sense for them to just be Class 43 locomotives and sets of coaches. The numbering system was simply a way of keeping track of assets, it wasn't handed down from a celestial power.

[Michael Hodgson]

28 minutes ago, Wheatley said:

 They were allocated set numbers in the 253/254xxx DMU series with the traction units numbered in the 43xxx series until somebody with a sufficiently large hat (or a sufficiently august committee behind them) decided that it made more sense for them to just be Class 43 locomotives and sets of coaches. The numbering system was simply a way of keeping track of assets, it wasn't handed down from a celestial power.

So the chap in the big hat only thought he was God ?  🤣

 

Numbers would certainly have helped accountants to keep track of the (mobile) fixed assets on their books. 

However they were probably of more practical everyday use to the people who had to drive or overhaul them.

[woodenhead]

HST a locomotive or a multiple unit?

 

Would a multiple unit do this?

 

or even more so, would a multiple unit power car do this:

 

It's like a class 86 or 86 at the back of a DVT headed train - if it is capable of driving on it's own then it's a loco, if it can only work in combination with a driving car(s) then it is a power unit.

 

We should also remember the prototypes had two cabs, it was capable of being driven (slowly) from the rear as well - a locomotive, the class 91 took this a step further and was a complete cab.

Edited November 7, 2023 by woodenhead

[C126]

If I may be the first to drag this thread off topic, please: what was Class 250 then?  Or was it a vacant number?  Thanks.

[The Stationmaster]

2 hours ago, Peter Kazmierczak said:

Here's my take on it, off the top of my head...
 

The High Speed Diesel Train (HSDT) was a railway engineering initiative to counter the aircraft engineering of the APT. The result is history...

The prototype HST (as the HSDT was relabelled) comprised a pair of locomotives between a set of Mk III (they tended to use Roman numerals then) coaches. It wasn't regarded as a unit; rather coaches between a pair of locos - much like the Edinburgh - Glasgow push-pulls of 1971. 

 

The Mk III were to be numbered in the normal coaching stock series of 32xx and 58xx - hence the gap in numbering in the Mk2e series. Soon it was decided to number them in a new coaching stock series, the familiar 10xxx, 11xxx and 12xxx series.

The two prototype locos were numbered 41001/2 in the loco series. 

Before the prototype HST entered service on the WR in May 1975, it was reclassified as a unit with the set number 252001. This followed on from the Blue Pullmans being considered as class 251.The class 41 locos were renumbered in a new coaching stock series 43xxx, with the coaches becoming trailers 40xxx, 41xxx and so on.

Come the production HSTs, the WR sets became class 253 and the East Coast ones class 254. The powered vehicles being classified as Driving Motor Brakes (DMB), or Driving Motors (DM) if they lacked guard's accommodation following the introduction of the TGS. These designations appeared on the end data panels of the vehicles.

So were the production HST power unit vehicles considered as locos? The idea of HST sets remaining static was very short-lived, with changes made right from the first days in service. Sometime in the 1980s the end data panels appeared with Class 43 on them, rather than DMB/DM. So was this when they were officially considered as locomotives again?

What I do know is that Derby Loco Works (who overhauled these vehicles), referred to them as power cars.

They were very definitely called power cars when the trains were in process of delivery to the WR.  Technicallt, as already mentioned above, they were not mu.tiple units but were basically worked as sets until a vehicle or power car had to be taken out for whatever reason.

[keefer]

I think when the HST vehicles were renumbered into the 40/41/42/43xxx series it was possibly the largest block of unused numbers and they were effectively numbered as multiple-units (even though they did not work sets in multiple with each other so let's not even go there).

The use of class 43 was a convenient stand-alone reclassification while still using the original numbers.

Regarding how enthusiasts often get het up about these things, I've seen some reference/arguments to 'Class 82' DVTs, which is nonsensical as they are not locos and the numbers are simply in the existing loco-hauled NPCCS series.

Edited November 7, 2023 by keefer

[Peter Kazmierczak]

Re class 250. 

I wonder if the Blue Pullmans might've been divided as:

 

250 = 6-car sets

251 = 8-car sets

Not 100% sure though.

[rodent279]

Interesting that they were numbered in the carriage series, 43xxx. When did the last MK1 suburbans numbered in that range disappear?