• Our new ticketing site is now live! Using either this or the original site (both powered by TrainSplit) helps support the running of the forum with every ticket purchase! Find out more and ask any questions/give us feedback in this thread!

What was the maximum speed of the diesel locos 10000/10001 ?

Justin Smith

Established Member
Joined
14 Nov 2009
Messages
1,415
Location
Sheffield
I was reading a past article in the Railway Performance Society fastest times supplements that dealt with fastest times with early BR diesel locos, including 10000 and 10001. And it set me wondering what the maximum speed of 10000 and 10001 was, though the less obvious question was did they have a rated maximum speed at all ?!? After all I don't think steam locos did, and in fact most of them didn't even have speedos !
Wiki report it as 150kmh/93mph, but that makes no sense to me, why would a British 1948 loco have had a maximum speed rated in km/h.....
Does anyone else know ?

And whilst we're at it what does the Wiki HP rating mean : 1,760hp gross, 1,600hp net (at 750rpm) ? After all the Class 40 (effectively the production version of 10000/1) doesn't have a separate "gross" and "nett" figures quoted.
Just out of interest the Class 56 had the ultimate version of the same engine with a HP/litre figure pretty much doubled : 3250hp at 900rpm (albeit with 4 valve heads, intercooling and cam drive cams). Apparently it had a potential output of 35020hp (at what rpm ?) !
 
Last edited:
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

Magdalia

Established Member
Joined
1 Jan 2022
Messages
7,291
Location
The Fens
And it set me wondering what the maximum speed of 10000 and 10001 was, though the less obvious question was did they have a rated maximum speed at all ?!? After all I don't think steam locos did, and in fact most of them didn't even have speedos !
Wiki report it as 150kmh/93mph, but that makes no sense to me, why would a British 1948 loco had a maximum speed rated in km/h.....
Does anyone else know ?
British Railways diagram DE/3000/1 says maximum speed 90mph.

And whilst we're at it what does the Wiki HP rating mean : 1,760hp gross, 1,600hp net (at 750rpm) ?

British Railways diagram DE/3000/1 says Maximum Continuous Rated Output 1600hp at 750rpm.
 

Harlequinuk

On Moderation
Joined
15 May 2025
Messages
328
Location
UK
The Bulleid D 16/2 were rated to 110 as they were designed for Express traffic ; so slightly quicker than the D 16/1 (LMS twins) who were geared for 90.

https://crecy.co.uk/product/southern-way-special-21

Simon Lilley has a book coming on the Bulleid model and i have asked for a future project for a book on the LMS twins, and i think he will.

If interested heres an audio recording of 10001 starting up Shap (10203 is passing going down at the start)

https://soundcloud.com/neil-ferguso...d&utm_medium=text&utm_campaign=social_sharing
 

ac6000cw

Established Member
Joined
10 May 2014
Messages
3,884
Location
Cambridge, UK
And whilst we're at it what does the Wiki HP rating mean : 1,760hp gross, 1,600hp net (at 750rpm) ? After all the Class 40 (effectively the production version of 10000/1) doesn't have a separate "gross" and "nett" figures quoted.

This is a pdf copy of an official English Electric brochure/magazine of the time describing "Britain's First Main-Line Diesel-Electric Locomotives": https://www.railwaysarchive.co.uk/documents/EnglishElectric_MainlineDiesels1951.pdf

A couple of quotes from it (my bold):
Maximum service speed 93 m.p.h.
The diesel engine, main generator and auxiliary generator form one unit which is supported on resilient mountings. The pressure-charged fourstroke V-type engine has sixteen cylinders, 10 in. bore x 12 in. stroke and is rated for this application at 1600 b.h.p. at 750 r.p.m. The brake mean effective pressure is 112 lb. per sq. in., and the piston speed 1500 ft. per min. at full load. Fuel consumptions at full, 75 and 50 per cent. load are 0·40, 0.389, and 0.402 lb. per b.h.p. hour respectively, based on a minimum calorific fuel value of 19350 B.Th.u. per lb. The maximum cylinder pressure is about 760 lb. per sq. in. The rating of this type of engine can be increased to 1760 b.h.p. at the same engine speed by increasing the fuel injected and to 2000 b.h.p. at 850 r.p.m.
 

Merle Haggard

Established Member
Joined
20 Oct 2019
Messages
3,850
Location
Northampton
Writing of official E.E. brochures; I obtained the one produced by them when what became the class 50s were being built. I still have it 'somewhere' I think.
At the end, there was a mention of E.E. pioneering British main line diesels and a stated intention for them to preserve one. That might be the reason for 10001 lingering on in store after the other pioneers - 10201/2/3 and 10000 - had been scrapped. Presumably the decline of E.E.s orders after 449 had been built was a factor, but it's a shame it never happened. Far more worthwhile than yet another 'Castle' in my opinion - and I'm a steam man.
Regarding speed limits; there were blanket speed restrictions by Region and I think I recall correctly that the ScR one was 75 mph, obviously including the EC and WC main lines. Possibly 90 mph elsewhere.
 

ac6000cw

Established Member
Joined
10 May 2014
Messages
3,884
Location
Cambridge, UK
Just out of interest the Class 56 had the ultimate version of the same engine with a HP/litre figure pretty much doubled : 3250hp at 900rpm (albeit with 4 valve heads, intercooling and cam drive cams).
That near-doubling of power output is not uncommon on engines with a long development history e.g. a couple of US examples: the EMD 567 V16 started out at 1350hp in 1938 (in the FT loco), reaching 2500hp in 1963 (in the GP35). The GE FDL V16 started out at 2500p in 1959 (in the U25B), reaching 4400hp in 1993 (in the C44-8W), and helped take GE from nowhere to No.1 mainline diesel loco builder in the US.
 

Justin Smith

Established Member
Joined
14 Nov 2009
Messages
1,415
Location
Sheffield
Writing of official E.E. brochures; I obtained the one produced by them when what became the class 50s were being built. I still have it 'somewhere' I think.
At the end, there was a mention of E.E. pioneering British main line diesels and a stated intention for them to preserve one. That might be the reason for 10001 lingering on in store after the other pioneers - 10201/2/3 and 10000 - had been scrapped. Presumably the decline of E.E.s orders after 449 had been built was a factor, but it's a shame it never happened. Far more worthwhile [to preserve 10000] than yet another 'Castle' in my opinion - and I'm a steam man.
Regarding speed limits; there were blanket speed restrictions by Region and I think I recall correctly that the ScR one was 75 mph, obviously including the EC and WC main lines. Possibly 90 mph elsewhere.

I agree completely.
 

Taunton

Veteran Member
Joined
1 Aug 2013
Messages
12,218
That near-doubling of power output is not uncommon on engines with a long development history e.g. a couple of US examples: the EMD 567 V16 started out at 1350hp in 1938 (in the FT loco), reaching 2500hp in 1963 (in the GP35). The GE FDL V16 started out at 2500p in 1959 (in the U25B), reaching 4400hp in 1993 (in the C44-8W), and helped take GE from nowhere to No.1 mainline diesel loco builder in the US.
Not that the final engines bear a lot of similarity to the originals, being fitted with turbocharging, intercoolers, increases in maximum rpm, hardened components, etc. The EMD 567 worked up through variants, and the 567C, 15 years after type introduction, brought a completely reworked coolant system, and looks quite different. The 567 is just a designation of the swept volume of one cylinder.

The (old) GWR had their 41xx 2-6-2T locos, and then the more powerful 61xx type. These were dimensionally the same but had increased boiler pressure allowed through use of a different grade of steel alloy. Were the boilers (and the loco) the same? The boilers were built to the same drawing (apart from the safety valve setting), just with different steel.

Regarding max speed of 10001 (which I once saw, lying withdrawn outside Derby depot with 10201-3), I don't think there was the concern in former times for a formal maximum speed, never to be exceeded. It was more a designers' specification for typical use, and possibly some minimum guarantee.
 
Last edited:

RT4038

Established Member
Joined
22 Feb 2014
Messages
5,444
Regarding max speed of 10001 (which I once saw, lying withdrawn outside Derby depot with 10201-3), I don't think there was the concern in former times for a formal maximum speed, never to be exceeded. It was more a designers' specification for typical use, and possibly some minimum guarantee.
I saw 10001 lots of times, standing in the roundhouse at Willesden MPD. Never saw it running though.
 

Merle Haggard

Established Member
Joined
20 Oct 2019
Messages
3,850
Location
Northampton
Spending Saturdays spotting at Roade I susally caught the 8 a.m. Northampton - Euston. The journey time to Euston was 1 hr 50 mins, so not a demanding schedule.
The usual power seemed to be express locos. in their dotage with the occasional 'Princess Royal' but my recollection is that 10001/1 and 10201/2/3 were fairly regularly on the train.
They were in green livery with steam loco style orange and black lining applied horizontally and we regarded them, like the 'Jackshaft' LMS shunters, as sort-of honorary steam locos.
No affection for the underpowered EE type 4s or Sulzer 2s, though.
 

Bevan Price

Established Member
Joined
22 Apr 2010
Messages
8,316
I don't know if there is any truth in this, but one story from the 1960s suggested that none were preserved because some of the parts could be used as spares in Class 40 or 37.
 

Harlequinuk

On Moderation
Joined
15 May 2025
Messages
328
Location
UK
I don't know if there is any truth in this, but one story from the 1960s suggested that none were preserved because some of the parts could be used as spares in Class 40 or 37.
Class 40 bogies were taken straight from the Bulleid Diesel (D 16/2) , in fact 10203 was built using one of the first Class 40 chassis and bogies straight from the factory! << The Southern Way Special Issue No 1, and soon to be Special Issue 21. Engine parts were useful for Class 40 and DP2. D 16/1 (loco in this thread) the bogies were used as a complete design for the Class 77, and a pair have come over from the Netherlands for the recreation
 

Top