10100 Fell loco

I have added 2 new photos to the Diesel prototype collection



British Railways 10100 was an unusual experimental diesel locomotive known informally as The Fell Diesel Locomotive (after Lt. Col. L. F. R. Fell, who was one of the designers). It was the joint production of Davey Paxman & Co, Shell Refining & Marketing Co and Lt-Col L. F .R. Fell, built for them by the London, Midland and Scottish Railway at Derby. Sir Harry Ricardo was also involved. By the time it emerged in 1950, nationalisation had taken place and it carried British Railways livery. The locomotive had six diesel engines, four of them used for traction. There were two auxiliary engines, both of which were 150 hp (110 kW) AEC 6-cylinder units, and these drove the pressure-chargers for the main engines and the purpose of this arrangement was to enable the main engines to deliver very high torque at low crankshaft speed.The design for 10100, a collaboration between Fell Developments Ltd and H. G. Ivatt of the LMS, aimed to address several of the weaknesses perceived of diesel powered rail traction. Weight was reduced by using several small engines, meaning that both the engines and their supporting structure could be lighter. This was also expected to save time in maintenance as an individual diesel could be exchanged more easily and with lighter equipment.



10100 Fell loco on the 3.12pm Manchester service at Ampthill 16th July 1955







https://railway-photography.smugmug.com/1/Pre-TOPS-Locomotives/Prototype-Diesel-Locos/LMS-10000-10001/i-4xM5j7N/A


LMS/B.R. 10000 & 10001 & Fell/LMS/Private consortium 10100 - Railway-Photography
railway-photography.smugmug.com
railway photographs from the last 100 years

10001 Ivatt LMS loco Willesden 18th March 1967









https://railway-photography.smugmug.com/1/Pre-TOPS-Locomotives/Prototype-Diesel-Locos/LMS-10000-10001/i-72B8Nkx/A


LMS/B.R. 10000 & 10001 & Fell/LMS/Private consortium 10100 - Railway-Photography
railway-photography.smugmug.com
railway photographs from the last 100 years

Neil

 

The Fell has always struck me as a loco even it's mother could not have loved.

Perhaps it's just as well it was not a success...

 

Not quite a failure !!

The principle of having separately excited traction motors and only adding them to traction when speeds reached a certain point is currently being advertised in the latest diesel locomotive designs from Germany. Whilst Fell was 60 years in advance of the technology typical UK unwillingness to develop the project has led to yet another UK initiative going elsewhere; the APT titling body was sold to Italy which sold us back the Pendelino project is yet another example of UK expertise being developed abroad. Whilst possibly tangential to the main discussion point (i.e. 10100 Fell Locomotive) I wonder how many other UK inventions have been cast aside by companies and developed abroad.

I even understand that after WWII the UK Government was offered the whole of VolksWagen as part of the reparations but UK industry turned it down because its model range was "too old fashioned" !!

 

That seems a bit of a stretch from the Fell's multiple diesel engines and mechanical transmission, to the "UK" (not sure who in particular) missing out on an opportunity for phasing in traction motors. Presumably it is not just speed but adhesion that would dictate if you want to drive a particular axle (not an issue with the Fell as it had one central gearbox)?

 

Yes, after the war, VW was offered to both Morris motors, and also to Ford, free. Both said it was rubbish and didn’t want it. They went on to sell 19 million Beetles!

 

I'm wondering if the

I'm wondering if the Ampthill shot date is right of July 1955 .I remember it catching fire on Northampton Road Bridge about 150 yards north of Kettering station ,much to the amusement of spotters who used to congregate there. The fire service were in attendance for some time. Due to plenty of failures it was always regarded as a bit of a joke. This was in 1953/4 ,it didn't do a lot of good after then ,in fact I don't think it was seen on the south end of the Midland main line again. The train is right on the photo' ,the half four Manchester thro' Kettering ,just as the Grammar school lads were leaving off .

 

A very interesting video and if the audio is real, 10100 made an unusual noise!

 

I remain amazed to this day that British Railways ever indulged Colonel Fell and his folly.

In Alexei Sayle's book "Train To Hell" there was a description of some dilapidated diesel that was brought back into service and 'modernised' by fitting twenty Vauxhall Cresta engines to it... so only fourteen more than the Fell.

 

Well, it didn't really cost BR anything to build, and the theory wasn't bad - keep your running engines at high power, where diesels are most fuel-efficient. A brave attempt, for sure, at what was, for British lines, still pretty new technology.

BR wasted far more money with the plethora of designs that emerged in the Modernisation Plan, only a few years later...

 

It had the advantage that a lot more of it could be built in BR's own workshops, compared to a diesel electric, and it put more power on to the rails than a de could achieve at that time, although of course they soon caught up.

 

I've just watched the film. What was actually wrong with the Fell loco? Was this just another instance of those in charge giving up because of teething troubles?

 

The fundamental problem is P = F * v, i.e. Power equals Force times speed.
For normal locomotives you have some source of approximately constant power, e.g. diesel engine or steam boiler.
That means for low speeds you should have high traction force and this drops at higher speeds, keeping the power approximately constant.

For the Fell loco you have the number of motors engaged is proportional to the speed, thus you have a loco with almost constant traction force.
Thus the acceleration will be bad and your train load is limited to what the loco can pull at full speed up the worst gradient on the line.
That will be a very light train if you run over e.g. Shap. It would be almost useless for goods trains.

 

Thanks for the link. Led to some wonderful stuff from Shell. The Croydon Airport was very interesting and the 1954 Dutch TT was just wonderful.

 

That is true if that constant traction force is low. But was it? What was the Fell's nominal TE?

 

You have 500 hp engines. Thus 500 hp at low speed, 1000 hp at moderate speed, not much to accelerate a heavy train.
And as said it is firmly dimensioned to take every grade at full speed, a very wasteful way to operate a train service.

 

Not so - it had 4x 500hp engines available for traction, and, of course, mechanical transmission isn't as 'lossy' as, say, diesel-electric transmission, so more of those 2000 horses could be put down to the rail than a 2000hp EE Type 4, as an example. It also had 2 auxiliary engines for driving Roots blowers to boost the charge air pressure of the prime movers.
https://en.wikipedia.org/wiki/British_Rail_10100

 

AIUI not all four engines came in at once though on starting so only 500 hp to get the train moving and then subsequent engines came in until all four were running when the train was well under way.

 

Wasn't the whole point that the engines were switched in and out using differentials? So the available power varied, between 500 and 2000hp, but the torque at the wheels could remain constant. I.E at the same speed, a 500hp engine geared down 4:1, will produce the same torque as a 2000hp bank running at 1:1.

The Fell design produced the high crankshaft torque, low engine speed necessary for starting because the 4 driving engines were fed air at a constant rate by two additional auxiliary engines that existed just to drive superchargers that supplied combustion air. The mass flow rate was constant, so at low starting speeds the engines were getting proportionately more air and generating more power, as the speed increased and more engines were started, the volume of air available per combustion cycle decreases so the power output drops.

I think the locomotive proved the principle was sound, it worked well enough for BR to purchase the loco outright and keep it in service for another 3 years. Even then, in the end it was the heating boiler that killed the thing and not a failure with the transmission. Solutions had been identified for some of the less desirable characteristics, such as the excessive noise and complex cooling arrangements for the proposed MkII.

 

Why was it converted from a 4-8-4 to a 4-4-4-4?

 

It wasn't, the transmission still powered all 4 axles as one but I understand removing the middle set of external coupling rods made the wheelbase less rigid. If you look at photos after the removal of the middle coupling rods, the outer ones are still lined up.