Class 710 Delivery / Entry to Service

Depends who you count as a TfL predecessor - British Rail certainly ran DMUs on (parts of?) the North London Line for a time, and it was only very recently that the local service between Paddington and Hayes & Harlington got it's first electric service. I don't think TfL has run any DMUs anywhere other than the Goblin (and occasional through journeys between there and Willesden) though.

Certainly with the Goblin I think the main takeaway for TfL is that they have failed to adequately project manage around other organisations' failures (and there has been no shortage of them). I get the impression that driver training for example has been ready to start just as soon as they have trains to be trained on for months now.

I think the reference was to LRT or London Transport.

A friend within Arriva Rail London (ARL) has given me a few snippets of information, the problem with the cl710 is (as has been often suggested) the software. It's not up to the required standard and therefore ARL will (quite understandably) not accept the trains until the software is fit for purpose.

A pilot training course was run last week to try and nail down what bugs were happening; apparently ARL and ASLEF both agreed that no more training could happen until the software is fixed. It's simply that buggy you can't actually learn on it because it keeps falling over.

That said, they did suggest some of the managers are receiving some training this week.

In light of the above the month's free travel that had been promised as compensation for when the service is fully restored might be a while off yet!

Various systems, notably the interface with then signalling, are rather more sophisticated than in the old days when it relied entirely on a driver seeing a light on a stick and reacting appropriately. Not only are the modern systems safer, but they are able to squeeze more trains through the same track, as a result of better braking systems (for example matching the braking curve to the weight of the train, and clever wheelslip detection systems). There are also the various systems prescribed by legislation, such as public address, systems to prevent people getting dragged by doors that have closed on them, etc.

And yes, there were problems with the early EMUs - notably when the entire fleet of AM2s operating out of Fenchurch Street (and the AM3s in Glasgow) were grounded following a spate of exploding transformers. That was in 1959.


Even further back, construction of the Bakerloo Line was suspended for a few years when the project ran out of money, only being completed when Charles Tyson Yerkes came to London to escape his creditors and bought up the moribund company (along with three others which hadn't even been started).

Passenger information systems are a major requirement. You can't just have a guard yell out the names of the next station these days as equality laws require it to be done in visual form as well.

Also, new EMUs have computers to assist in fault finding; they can report back in real time to the depot as to what is wrong, saving time taking the unit apart to find the fault.

The only AC units the LMR had in the early 1960s were the AM4s, which looked very similar to the AM5s, so it was probably them. Forty years later, towards the end of their working lives, ex-LMR 310s found their way onto the Great Eastern and Tilbury routes, but I doubt they worked the Chingford services.

Looks like a 710 is back out today - perhaps for the managers' training as you said. Nothing ran Monday or Tuesday. Interesting that the trains are still deemed too buggy given the runs last week ran pretty much to time but that is just one of probably hundreds of aspects that Bombardier and others are looking at. There are also continued overnight runs on the WCML. This at least is movement on from having trains sat in depot going nowhere.

For those bemoaning the use of new trains there seems to be a bit of memory failure going on. When the 172s turned up they kept breaking down and there was all the furore over the exhaust systems potentially not being compliant. I believe the 378s also didn't have a fault free introduction either. Every so often we have to go through a generational change in train design because requirements change, passenger expectations change and technical and safety standards change to reflect lessons learnt over previous decades. The Aventra is a step change in train design. When it works it has the potential to be vastly more reliable and cheaper to run than previous train designs. That's not to excuse the enormous delays in getting the things tested and certified but perhaps it partly explains things. There are a load of new technical challenges that have to be resolved. AIUI not all of the issues that have been encountered are down to Bombardier anyway. Some of it is the infrastructure performing in ways that were not expected - i.e. outside the range set in standards. Bombardier have built a compliant train but it stops working (correctly) when it encounters non standard power ratings in the electrification. That's not Bombardier's problem - that's the result of how NR have designed and built the electrification infrastructure and power feeds and the level of use at certain times of day on lines away from the GOBLIN.

I'm as fed up as the next person with what is (not) happening with the 710s but I do think we will get there eventually. It's just a very long slog and not all of the issues are to do with the GOBLIN electrification either. Demands to get Crossrail working and delivered will also be putting a squeeze on technical resources.

Thanks; it was indeed the AM4s. They had a different shade of green from what became AM5s, with twin yellow lining bands at waist level. AIRI, they were also 4-car units, making a rush hour Chingford train 2x4 rather than 3x3 cars

<< the AM4s were actually used on the Chingford line as well>>. The Chingford line was all 6250v at the time, of course
Yes, I think this was documented in the Line 112 Group's "Railway to Walthamstow and Chingford" published some 50 years ago. I also seem to remember the AM4s mostly ran with the lavatories locked out of use (unwelcome to a small boy), and lavatories were not seen on the Chingford line till the 317s started helping out..
I thought the LMR (or rather, its successors) were actually to *blame* in the present situation, by demanding release of the 172s!

Yes, there’s quite a few built but because they are destined for West Anglia there’s not really any point in bringing them down until they sort out the /2s for the GOB

There seem to be fairly regular overnight runs on the WCML at the moment. Two were out on Friday night. I've no idea if this is for software testing or mileage accumulation or something else.

There are training paths on the GOBLIN WTT but very few trains have run in those paths over the last week. A couple of paths were used last week for a Managers Training Course but that's it. 710s were out the week before for driver instructor / ASLEF reps to experience the trains but the result of that was that driver training would not proceed because the trains were "too buggy". This leaves the issue squarely with Bombardier to resolve whatever is wrong with version 28/29/30/3? of the software.