If The Pilot Scheme Hadn't Been Botched..........

[The Johnster]

The Hymeks (I speak from direct experience) were pocket rockets that could perform far better than their physical size implied.  They were also very good riders, probably the best of the Hydraulics and I would suggest better than any other UK Bo-Bo on those long wheelbase bogies, and had very comfortable and warm cabs; their replacement on the 90mph 00.35 Cardiff-Peterborough parcels by the risible class 25s was a brutal shock to body temperature, eardrums, and spinal columns.  Anyone who saw (or heard!) one lifting over 900 tons out of Aberthaw Cement Works on a dry rail would be somewhat re-assured about their ability in the South Wales coalfield, especially as IIRC the D7101 series were to be lower geared as replacements for the 56xx, another pocket rocket...

 

But I have doubts that a B-B would have really cut the mustard in the Valleys rough and tumble; the 37, with it's relatively light weight (for a diesel electric, it was still 2 coal wagons heavier than a Hymek) and 6 driven axles, performed very well in the event.  One of the reasons for Beyer Peacock going under was that they had laid out cash on the materials for the D7101s but had to wait for delivery for payment from BR.  This was during the middle of a loco supply crisis on the Western caused by problems with the Warships blocking bays at Swindon and teething/delivery problems with the Westerns, and was in the nature of a last straw.  Fortunately for the WR, EE were in a position to supply class 37s quickly, and they were a proven success already on the ER and NER.  The Hydraulic experiment was holed below the water line, and the WR's further type 4 requirements were met by Brush/Sulzer class 47s.

 

I rather liked Hymeks!  

Edited February 23, 2018 by The Johnster

[The Stationmaster]

The decision to abandon hydraulics was not taken until much later.  The reason for the larger class 37 orders was that Beyer-Peacock was going under and could not complete the contracted number of Hymeks, so more class 37's were ordered to make up the shortfall.

 

It would have been interesting to see how well the Hymeks would have performed on the south wales coal trains!

 

And of course the fact that the two classes had been specifically tested against each other on various jobs in the South Wales Valleys and the EE design really scored by virtue of its greater braking power (82.3% of 103 tons 1cwt against 73.3% of 75t 8cwt for the Hymek).  The other advantage of the EE design was that it's axle load was 17t6cwt on its heaviest loaded axles (no boiler version) against 19t4cwt on the heaviest loaded axles of the Hymek and both could work over the same minimum radius of curvature - 4 chains.  The tractive effort of the EE design was also greater but that was not particularly relevant on the Valleys where the important, and most difficult, part of working was stopping trains rather than starting them.  I understand that during the trials the Hymek actually produced better results in some cases as it was far less prone to wheel slip when applying power but overall the EE design scored better all round on Valleys work and indeed on general freight work in the area hence EE got the order instead of it going to the diesel hydraulic design.

[jjb1970]

The thing that has always puzzle me about the diesel hydraulics is that in other applications the selling point of hydraulic torque converters is their reliability and virtually bomb proof durability. They're often used in applications where dependability is critical, they're not especially efficient or cheap but they are reliable and considered simpler and less prone to failure that electric drives.

[Pandora]

The production fleet of Hymeks D7000 - D7100  total fleet of 101,  why the eccentric fleet size  of 101 and not 100?  Did BR Western region intend to order another batch and if so how many? Post 326 states the D7101 series were to be re-geared, did Beyer trial a re-geared Hymek? D7100, was it the same gearing as the earlier members of the fleet?

[Kelly]

The thing that has always puzzle me about the diesel hydraulics is that in other applications the selling point of hydraulic torque converters is their reliability and virtually bomb proof durability. They're often used in applications where dependability is critical, they're not especially efficient or cheap but they are reliable and considered simpler and less prone to failure that electric drives.

Some of that is down to a mixture of politics (licence building only as German supplier was deemed politically problematic at the time), build quality (in the case of nbl, their building quality and tolerance was much less than voith or man etc would have provided, similar for other license holders) and experience to some extent.

 

Today it has the benefit of 60+ years of development behind it, being built by experienced companies in those fields. Back then it was certainly very new, especially in the UK.

 

The problem at the time diesel electric had, was electric motors were DC, which were bulky and heavy, but ac motors weren't considered viable really until the 1990s (at least for units, not sure about locos?) when the 457/316 units were used to test brush and GEC ac traction, prior to the 465 networkers being introduced. Since then pretty much all electric motors have been ac, with conversion done from the supply, creating supply agnostic units in effect

[The Johnster]

The production fleet of Hymeks D7000 - D7100  total fleet of 101,  why the eccentric fleet size  of 101 and not 100?  Did BR Western region intend to order another batch and if so how many? Post 326 states the D7101 series were to be re-geared, did Beyer trial a re-geared Hymek? D7100, was it the same gearing as the earlier members of the fleet?

 

BR had placed an order with Beyer Peacock for 100 low geared Hymeks, to be numbered D7101-D7201, but the company failed before building could start and they never materialised.  The idea was to replace the remaining 56xx steam engines in South Wales; I believe they were to be geared for a maximum speed of 60 mph instead of 90.  No prototype was ever produced, and D7100 was a standard class 35 90mph Hymek.  No lower geared Hymek was ever built, much less ran and tried.

 

I have no idea why the original order was for the odd number of 101 locos!

[The Johnster]

The thing that has always puzzle me about the diesel hydraulics is that in other applications the selling point of hydraulic torque converters is their reliability and virtually bomb proof durability. They're often used in applications where dependability is critical, they're not especially efficient or cheap but they are reliable and considered simpler and less prone to failure that electric drives.

 

In the case of the D8xx Warships, based on the successful German V200 class, ran into trouble for several reasons, one of which was build quality of the Maybach engines manufactured under license in the UK.  Another factor was that the V200s in general worked on secondary main lines in Germany (the trunk routes were already electrified by then) and their work was not as strenuous as the continuous high speed thrashing that the WR had to put them through to run to steam timings and loads.  It is significant that later WR timetable improvements were only possible with increasingly restricted loads, even when Westerns and Brush Type 4s were employed.

[adb968008]

BR had placed an order with Beyer Peacock for 100 low geared Hymeks, to be numbered D7101-D7201, but the company failed before building could start and they never materialised.  The idea was to replace the remaining 56xx steam engines in South Wales; I believe they were to be geared for a maximum speed of 60 mph instead of 90.  No prototype was ever produced, and D7100 was a standard class 35 90mph Hymek.  No lower geared Hymek was ever built, much less ran and tried.

 

I have no idea why the original order was for the odd number of 101 locos!

I wonder if that would been class 35/1 or class 36 ?

[rodent279]

I wonder if that would been class 35/1 or class 36 ?

On that note (and this may have been covered elsewhere), why were Hymeks not renumbered into TOPS? I know they went early, but many class 24's didn't last a lot longer either.

[kevinlms]

I wonder if that would been class 35/1 or class 36 ?

Or something else entirely. This the Western Region! Plenty of choices in the 3X range.

[jjb1970]

The big revolution in the 80's was the commercialisation of reliable frequency control equipment rated for high power. Nowadays solid state rectifiers and inverters are so common and cheap they're taken for granted but in the 80's it was cutting edge stuff and variable speed drives were hideously expensive. I still remember working with ward-Leonard systems and double cage motors.

[Rugd1022]

On that note (and this may have been covered elsewhere), why were Hymeks not renumbered into TOPS? I know they went early, but many class 24's didn't last a lot longer either.

 

They weren't renumbered because they were all supposed to have been withdrawn by the end of 1971 (a massive Hydraulic cull took place in October), but the WR motive power shortage meant they lingered on until March 1975. Likewise with the Westerns, they were supposed to be gone by the end of 1973 but kept going until February 1977.

[D9020 Nimbus]

I always understood that the Westerns kept their numbers because they were plates rather than being painted on.

[rodent279]

So how were hydraulics recorded on TOPS itself? As 35017, 42021, 52015 etc?

[Zomboid]

They just kept their D numbers, from what I've understood of the other thread we had recently. The class numbering and TOPS being independent of each other, and only coincidentally happening around the same time.

Presumably they're still known as 1015 etc.

[dibber25]

The Hymeks (I speak from direct experience) were pocket rockets that could perform far better than their physical size implied.  They were also very good riders, probably the best of the Hydraulics and I would suggest better than any other UK Bo-Bo on those long wheelbase bogies, and had very comfortable and warm cabs; their replacement on the 90mph 00.35 Cardiff-Peterborough parcels by the risible class 25s was a brutal shock to body temperature, eardrums, and spinal columns.  Anyone who saw (or heard!) one lifting over 900 tons out of Aberthaw Cement Works on a dry rail would be somewhat re-assured about their ability in the South Wales coalfield, especially as IIRC the D7101 series were to be lower geared as replacements for the 56xx, another pocket rocket...

 

But I have doubts that a B-B would have really cut the mustard in the Valleys rough and tumble; the 37, with it's relatively light weight (for a diesel electric, it was still 2 coal wagons heavier than a Hymek) and 6 driven axles, performed very well in the event.  One of the reasons for Beyer Peacock going under was that they had laid out cash on the materials for the D7101s but had to wait for delivery for payment from BR.  This was during the middle of a loco supply crisis on the Western caused by problems with the Warships blocking bays at Swindon and teething/delivery problems with the Westerns, and was in the nature of a last straw.  Fortunately for the WR, EE were in a position to supply class 37s quickly, and they were a proven success already on the ER and NER.  The Hydraulic experiment was holed below the water line, and the WR's further type 4 requirements were met by Brush/Sulzer class 47s.

 

I rather liked Hymeks!  

 

So did I, but with hindsight. It used to annoy me that I wanted rides behind Westerns or Warships but usually got a Hymek instead. Some of the performances were way more fun than with the Type 4s. I recall when the 1.25pm (SO) Oxford-Evesham was dieselised (in steam days it was any old 4-6-0 from Oxford shed) we got a Hymek on two coaches. The acceleration away from those little wayside stations was matched only by my first ride on a Clacton electric! (CJL)

[rodent279]

They just kept their D numbers, from what I've understood of the other thread we had recently. The class numbering and TOPS being independent of each other, and only coincidentally happening around the same time.

Presumably they're still known as 1015 etc.

So they actually got entered into TOPS as D1015, D821 etc? I always thought the rationale for renumbering was that TOPS could only handle 5-digit numbers, starting from 01001, and with the lowest number in each class being xx001.

[Zomboid]

I'm not a TOPS expert, but as it was bought from the Southern Pacific, it could clearly handle different length numbers. SP used 4 digit loco numbers, and American freight car numbers can vary in length.

 

Check out the other thread for a proper explanation by people who know what they're on about.

[The Johnster]

IIRC, but it's a long time ago and I cannot guarantee that I do, the only hydraulics I had anything to do with at Canton after TOPS came online were Hymeks and Westerns, and we continued as traincrew (I was freight guard, but this applied to loco crew as well) to enter the 4-digit pre-TOPS number of any loco that carried them until they were repainted with the TOPS numbers, which was never in the case of the hydraulics.  We used the number that was on the loco on our own written documents; guard's journals, notebooks, train preparation slips and so on.  

 

The TOPS document as far as trains were concerned were a computer printout version of the previous 'load sheet' consists, and contained the loco number in TOPS format followed by individual wagons in order with wagon type, loading, and wagon number.  IIRC, but see comment above, the printout contained the loco number in TOPS form, so 35 098 for D7098, or 52 013 for D1013, but it was only on such documents that this appeared, and the same applied to other locos that retained their 4 digit numbers after TOPs began.  As the numbers on these hydraulic locos were cast aluminium for the Hymeks, or on cast number plates for the Westerns, the D was removed on the Hymeks (with the location holes left bare) or painted out in black on the Westerns post August '68, when the last steam locos were withdrawn.  I cannot comment on the AL series 25kv electrics, which also had Hymek style cast numbers, as they are beyond my field of expertise, except to say that their cast numbers were replaced by painted TOPS numbers and the cast lion device by painted 'arrows of indecision', which I thought was a retrograde move.

 

This is a whole subject in and of itself, with different fonts being used before a TOPS standard was imposed, numbers in different locations on different locos even within the same class, different application of TOPS information panels.  In it's way it is as variable and interesting as any livery changeover period, with two sequences of renumbering to boot, firstly the removal of the D post 1968 and then the TOPS numbering, all overlapping.  It probably doesn't deserve a book, but there's enough in it for a magazine article.  I am not volunteering to write it, though!

[Rugd1022]

So they actually got entered into TOPS as D1015, D821 etc? I always thought the rationale for renumbering was that TOPS could only handle 5-digit numbers, starting from 01001, and with the lowest number in each class being xx001.

 

I've seen Tops print outs from 1976 and 77 showing 1013, 1023, 1056 etc, belonging to fellow bashers who rode on many of the official tours at the time, so Tops was able to recognise them with their original numbers. 

 

These days the likes of D1015 etc are identified in the 89xxx series, the number is painted inside both cabs.

[rodent279]

Straying well OT here, I know, but that implies that TOPS can translate between two different numbers for a loco, so begs the question why bother renumbering at all, when you can enter the original numbers, and TOPS would be able to do a lookup to the locos TOPS number? Why not just number all new stock in the TOPS series?

I'm no expert in databases, but I've used enough of them to know that it's not difficult to cross reference like this. In the cellular radio world we have cell site identifiers in more than one form.

Edited February 26, 2018 by rodent279

[kevinlms]

Straying well OT here, I know, but that implies that TOPS can translate between two different numbers for a loco, so begs the question why bother renumbering at all, when you can enter the original numbers, and TOPS would be able to do a lookup to the locos TOPS number? Why not just number all new stock in the TOPS series?

I'm no expert in databases, but I've used enough of them to know that it's not difficult to cross reference like this. In the cellular radio world we have cell site identifiers in more than one form.

Because its easier in the long run for every user of the system, to be able to pick out members of a class of locomotives.

 

Assuming the LMS had a TOPS system in the 1929s/30s, the various 0-6-0 goods tender loco would have easier to work out their power classification. The LMS had lots of 2F's and 3F's, which kept their numbers, even though they changed boilers and technically went from 2F to 3F, or 3F to 2F & back again in some instances. So the block of numbers actually carried, didn't tell you that information and so was of little help at all.

[Mark Saunders]

There is a lot of judging the past by the standards of the past in this thread now!

 

Each number series was allocated and the 10XX series was in those allocated to PO wagons!

 

Mark Saunders

[The Stationmaster]

I'm giving up on this thread - there's so much utter nonsense appearing recently, and people not bothering to read other threads so simply going over ground that has already been covered in detail,  it's not worth looking at it any more.

Edited February 26, 2018 by The Stationmaster

[D9020 Nimbus]

There was a plan for a Swindon diesel-hydraulic type 2, it would have resembled a smaller version of the DB V80, so not at all like a Western, more like a Bo-Bo version of a class 14 (which was based on the German V60). It featured in an article some years ago in, I think, Backtrack.