The Formation Of A Class 710 Train
This morning, I was able to look at the plates on all four cars of a Class 710 train.
Here is the formation of the train.
DMS+PMS(W)+MS1+DMS
The plates on the individual cars are as follows.
DMS – Driving Motored Standard
- Weight – 43.5 tonnes
- Length – 21.45 metres
- Width 2.78 metres
- Seats – 43
The two DMS cars would appear to be identical.
PMS 
-Pantograph Motored Standard
- Weight – 38.5 tonnes
- Length – 19.99 metres
- Width 2.78 metres
- Seats – 51
The signifies a wheelchair space.
MS1 – Motored Standard
- Weight – 32.3 tonnes
- Length – 19.99 metres
- Width 2.78 metres
- Seats – 52
It is similar in size to the PMS car, but has an extra seat.
These figures add up to the unit figures you would expect.
- Weight – 157.8 tonnes
- Length – 82.88 metres
- Seats – 189
But what else can be said?
All Cars Are Motored
All four cars are motored, which is not an arrangement seen very often in UK electrical multiple units.
- Most British Rail units like Class 317, 319 and 321 trains have only one motored car.
- Five-car Class 800 trains have two trailer cars and nine-car trains have four trailer cars.
- Eight-car Class 700 trains have four trailer cars and twelve-car trains have six trailer cars.
Class 345 trains which are also Aventras, have eight motored cars and only one trailer car.
I suspect that it is an arrangement that gives advantages, over the weight and cost of the extra motors.
Less Force Between Wheel And Rail
The tractive and braking force between the wheels and the rail will be less to get the same acceleration and deceleration, as the force will be divided between all traction motors and wheels.
Does applying the power at all wheels mean that the train accelerates and decelerates faster, thus cutting station dwell times?
Does this mean that wheel slip, which damages wheels and rails is less likely?
Are the lower power traction motors more reliable?
Can A Motored Car Be Changed Automatically To A Trailer Car?
Suppose a traction motor or its controlling system packs up, can the train’s central computer switch it out and effectively convert the errant motored car into a trailer car.
On a 710 train, that would mean a 25 % loss of power, but surely the train has sufficient power to be driven to the next station?
Equalisation Of Forces Between Cars
The forces between the four cars must be equal and possibly low at all times, as you have four identical individually-powered, computer-controlled vehicles moving in unison.
Does this give passengers a smoother ride?
Does it mean that walking between cars is an easier process?
I think so and I can only think of the problems of getting a four-person pantomine caterpillar working properly!
A Logical Way To Power A Train
Could it be that this is the logical way to power a train, but you need precise computer control of all cars to take full advantage?
It strikes me that getting it right could be a very difficult piece of computing, so has this been causing the delays for the Class 710 trains?
I don’t think we’ll know the answers to all my questions, until Bombardier publish a full authorised philosophy.
Twenty Metre Long Cars
British Rail designed a lot of trains to be eighty metres long give or take a metre. So there are a lot of platforms in the UK, that can accommodate an eighty-metre long train.
All of the London Overground routes, where these trains will run have platforms that can accommodate 80, 100 or 160 metre long trains.
So they could be run by a single train or two trains running together as appropriate without any expensive platform lengthening.
The Two Driving Cars Appear Identical
This must be logical.
Many older electrical multiple units have different driving cars.
Sod’s law states that one type will be less reliable than the other, so you’ll end up with a shortage of trains.
But if both driving cars are identical, you have much less of a problem.
What Will Be The Formation Of a Five-Car Class 710 Train?
If all cars are to be powered then it will be.
DMS+PMS(W)+MS1+MS2+DMS
MS2 and MS1 would be identical.
Would you really want to add a new trailer car into the fleet to complicate maintenance?
Why Are The Trains For The Lea Valley Lines Not Eight-Car Trains?
On the Lea Valley Lines, London Overground have said that they’ll generally run two four-car trains as an eight-car train.
In Latest On The New London Overground Class 710 Trains, I discussed the possibility of changing the order to a number of eight-car trains and felt there could be advantages.
- Higher passenger capacity in the same train length.
- An eight-car train would contain only two DMS cars instead of four.
- Trains could be built as two four-car half-trains, to improve reliability.
- Passengers would be able to walk the full length of the train.
Bombardier and London Overground must have analysed this and as they have more information than I do, they have come to a different conclusion.
Is there for instance, a safe procedure, that uses the operational train to transfer passengers to a safe place and then drag the failed train to appropriate parking?
- With an eight-car train, you’d have no operational train to take passengers to safety.
- With two four-car half-trains, as in Crossrail’s Class 345 trains, would you have other problems? But the Croosrail trains are designed for a long tunnel, with difficult evacuation problems.
There must be a very valid reason.
Conclusion
The Class 710 train has been well-designed and is not your normal suburban train.
Politics Just Got Even More Interesting!
I don’t know about politics, but I like to think I know about data and I have a long and deep memory.
We now have two immovable and possibly unstoppable forces on opposite sides, which have almost equal support.
- Those that want to leave the European Union without a deal.
- Those that want to remain in the European Union.
They are irreconcilable positions.
I remember an acrimonious takeover attempt by Imperial Chemical Industries for Courtaulds in the 1960s. Not so much, at the time but because I later worked for ICI and became friends with a guy, who had worked for British Nylon Spinners at Pontypool.
Later I became aware of Frank Kearton and his part in the stopping of the takeover.
At the time he was the Engineering Director of Courtaulds. In a Press Conference, the CEO of Courtaulds was floundering and giving a rather bad impression. A question was asked and Frank Kearton stepped in and answered it so well, he took over the Press Conference.
He became CEO and the takeover was defeated. Kearton went on to have a respected career.
I may have remember the story wrong and I suspect it’s Kearton’s version, that I’m repeating.
In the UK are in a similar position to Courtaulds in the sixties. Both major parties are almost leaderless and none of those at the top of the Tory, Labour and Liberal Democrat parties are better than the average run-of-the-mill MPs, who generally do a good job.
We need someone to step forward to unite this country and sort out the mess.
Will he or she be one of the following?
- Jeremy Corbyn – Anybody that far left and over seventy would be unacceptable to well over half of the population.
- Boris Johnson – You might employ him as a salesman, but you wouldn’t employ him in any management position.
- Vince Cable – Too old and he’s sensible enough to know it.
- The herd of Tory leadership candidates – Perhaps one might have the qualities, and they would need to show amazing style, intelligence and oratory to even get on the final ballot.
- Nigel Farage – The other side believe he’s the cause of the problem, so wouldn’t follow him.
- Caroline Lucas – Green policies are anathema to perhaps seventy percent of the country, who still fly too much and don’t buy zero-emission cars?
We need someone with amazing qualities to step out of the shadows, just as Frank Kearton did at Courtaulds.
Conclusion
I’ve put a small bet on my choice for the next Tory Leader and Prime Minister.
The Anonymous Widower 