Titan

I might be a bit slow, it has taken me until now to realise the thread title is miss-spelt...

I think it was usual to have at least one death per season, not unknown for there to be more than one death in a weekend. in those days the odds of a driver surviving until retirement were pretty dire.

This was done as a trial on the A14 on the steeper hills between the M1 and A1. Two lanes, outside lane restricted to vehicles of not more than 7.5 tonnes. It worked very well and now the restrictions are permanent. It will help lorries by encouraging them to only overtake on stretches where they actually stand a chance of completing the maneuver. If they do get stuck behind something slow then it is usually not that far before the restriction ends, where they will then be able to overtake it quickly.

I sometimes find it a little strange that the emphasis is on making the OLE masts as unobtrusive as possible. Lets face it, no matter what you do six or seven meters of mast just simply is not going to blend in. I think that if you can't hide it try to make it beautiful. My suggestion of fluted tubular masts with ornate scroll work and 'GWR' cast in the corners of the knee braces was a little late in the day...

This is the arrangement for 'low encumbrance' That is for when a small distance between catenary and contact wire is required, for example on approaching a low bridge in order to minimise the overall height of the system - it is no coincidence that there is a footbridge in the background. The two brackets hanging down vertically can be swung in the along track direction to any angle required up to and including horizontal to cater for very low system heights down to 280mm. In this case the catenary would actually go between the registration arm and the registration tube to which the arm is attached.

No, it was just ramped down.

I was thinking it looked like an all green one escaped from the southern region?

So using a lightweight diesel running at 1500 rpm is a dead end? That must be why they used a 16CSVT in the HST, oh wait...

They even have tassels!

I wonder how many people have realised that's exactly the tactic Gerry Fiennes used to persuade the board to buy the Deltics instead of a lesser diesel? Because of the Deltics speed, they had time to haul more trains in a day than any other loco could, which compensated for their higher capital costs and running costs. But that was not the most significant cost saving. Deltics were just fast enough that a crew could work Kings Cross to Newcastle and back in a single shift, which meant that not only did it not need to be a lodging turn, but crews could work two trains instead of one which of course meant a big increase in productivity. And of course that included guards, catering staff etc as well as drivers and second men so the cost saving in using Deltics was very significant. At least significant enough for the accountants of the time to agree and let Gerry get his Deltics!

He did hit the 'knitting'. If you look carefully you can see the cantilevers supporting the nearest wires in the background start to move just after the truck gets half way across. Somehow he manages to snag the first wire without a flash and a bang - possibly it is lower voltage, 1500V dc? and the rubber tyres of the truck provide sufficient insulation. It seems that we only get a flash when he carries the wire(s) far enough to contact and short out the support mast on the other side, whereupon we get a big flash in the vicinity of the base of the mast. This further suggests that it might be 1500V dc, as some systems have a special earthing bond. In order to help reduce stray currents they are earthed by what could be described as a high voltage fuse. Under normal circumstances it is an insulator, but should the voltage on the mast raise above a safe level it shorts out earthing the mast. Having to cope with the maximum current from all lines simultaneously rather than one may be why there is such a flash at the base.

There is plenty. Apart from scheduled services to Hull, operating Leeds-York and other off wire destinations, there is the need for the ability to use non electrified diversion routes either in emergency or planned engineering works. As a consequence most non-electrified junctions along the ECML have to be assessed for pan raising/lowering.

British OLE was done on the cheap. This means that there is less tension in the wires than elsewhere. Less tension means lower radial loads which means cheaper structures further apart can be used. The downside is not only is our OLE worse at coping with multiple pans and wind, it means it takes less kindly to a pan raising and subsequently bouncing at speed. On the GWML the new equipment has higher tensions so this is less likely to be a problem. On the ECML there may be more concern. However when changing over on the move the Class 800's are designed to raise the pantograph more slowly so as to give more of a 'soft kiss' to our delicate OLE. In this case it is unlikely that raising the pan at line speed will be an issue, providing it is done clear of crossovers, bridges, level crossings or other features which may have an adverse affect.

The technical side is not so bad, it is intended to put balises prior to the junctions required much in the same way that the Pendolino has balises telling it is OK to tilt. Thus when it runs over one the diesel engine powers up and the pan drops in plenty of time before the wires run out. However there are some issues. Firstly the train has to know which way it is going at the junction so it can take appropriate action. Might be difficult to achieve if an unscheduled diversion is required at the last moment. Secondly it is unlikely that raising the pan at high speed will be allowed, and if it is necessary for the driver to remember to slow down then that is driver intervention and not fully automatic. If the train was slowed down automatically without driver intervention that would open a whole new can of worms...

The changeover is supposed to be fully automatic with no driver intervention. However I get the feeling that this is just an aspiration that might be somewhat difficult to implement in practice...

Bearing in mind that in the five photographs in the post immediately preceding yours there are several examples of two gantries being used where it might seem that one would do, I hope we are forgiven for not guessing you did not mean those... Perhaps quote the post concerned next time to avoid confusion?

Could be down to the interference current monitoring software. Go over the limit and the loco sits down in order to save the signalling. There seemed to be quite a lot of paranoia about how such a complex and powerful loco might affect signalling circuits, and unfortunately the limits set were far below the amount of interference that other locos put out which everything seemed perfectly happy with. A probably little known fact - Due to the immense power of these locos the buffers and drawgear are insulated to ensure that all the return current when operating on third rail actually goes through the brushes on the axles rather than finding its way through the drawgear and bearings of the wagons behind...

I agree with all except this bit - it was not a chance, it was pretty much a certainty!!!

Quite a number of good reasons. First two off the top of my head: Possessions. A four track gantry may require a complete line block to install. Two two track gantries may only require possessions of the slows or fasts, thus enabling the railway to stay open and construction to be sped up. Height difference - Sometimes the height of the slow line track can be considerably different to that of the fasts. Trying to support all equipments from one boom would result in either insufficient clearance under one side, or 'stovepipes' too long such they get a bit too flappy to support the loads. Installing two booms at different heights gets around this.

It would appear that the driver may have saved several injuries due to flying glass, there may be several people there that owe him their sight.

It is all down to the loading. The Hexagonal ones shown in post 1827 are anchor structures, and are both deeper in width as well as height and also have struts to help take the load. On others the section is decided according to the width of the portal and the number of registrations that they will take. There is a reasonable amount of standardisation, For example one of the portal boom sections is identical to that of the two track cantilever, so that the same fittings to attach the registrations can be used for either.

I don't think the class 89 were axle hung, more like bogie mounted as per HST and most other BR electrics (notable exception being class 86 which were axle hung)

I wonder if it is providing cover for a 92 that would normally be at Dollands Moor?

Yes there is. It warns against using a DCC version with an old DC controller. The output of which can be so noisy that the decoder does not recognise that it is on DC and therefore does not respond. The peak voltage they put out can also be very high, which may cause damage. Try putting a small non-electrolytic capacitor in parallel with the controller output, and see if that helps - but don't turn the power up too high!