Recent content by MarkyT

Signalling around Aylesbury is also controlled from Marylebone. Up trains disappear onto TfL just north of Amersham, then reappear on the IECC screens just south of Harrow-on-the-Hill.

For Absolute Block lines, some boxes are designed for signallers to clear signals for main through routes in both directions, then switch out, which literally means using a big switch to disconnect the local block instruments, bells and telephones and connect the block lines on either side...

The old mechanical signalbox at Marylebone was out in the throat, not in station buildings closely surrounded by public areas and station traders. An evacuation of the station caused by an alarm fault probably wouldn't have closed the SB, but clearly they wouldn't be running any more trains...

No signalbox or control centre has a backup site. There's a lot of engineering resilience built into the system, however: Duplicated power feeders, uninterruptible supplies for the main systems, twin diversely routed trackside datalink cables, etc, but none of that can help in an evacuation...

Unless the particular platforms are very wide, having individual controllable gate lines for each long-distance terminal platform pair at a very busy station like Paddington can be undesirably restrictive, as you're placing them at a narrow point at the platform head. A wide shared gate line can...

I asked Google about the electrification of Newton Abbot-Plymouth. It estimated 3 to 5 minutes might be saved by electrification alone, as speed is still constrained so much by curvature. I asked it to compare that with the notional straighter cutoff illustrated in my previous post, combined...

I asked Google AI a series of questions about the performance of IETs on steep banks. I include one answer in full as it's fascinating. I've not checked the figures, but the conclusions seem reasonable: Me: Google: So it seems there's little point in speeds above 55mph on Dainton. A non-stop...

Agreed, for a half hourly local service extension to Goodrington the single line stub should be short and only contain the terminus platform. The minimum ROL length under modern standards is ~46m (50yds). The overlap/clearance IBJs might move a little closer to the points, but you'd still lose...

I don't think it ever got any further than rather vague notions of Swiss style light rail. I bring you the new Brixham branch, with a new cut off from Paignton gaining the old formation then leaving it just past Churston Ferrers to dive into a 1.8km tunnel descending at ~1:30 to emerge in the...

Aside from the train length limitations in the platforms at Paignton that prevent usage by 10 car 22x and 80x trains, there are other constraints that affect combinations of movements. In the following diagram, showing the revised north junction and a passenger conversion of one of the sidings...

The station at Paignton, near the town centre, bus station, hotels and beach is what attracts the punters. I doubt a limited steam operation just from Churston to Kingswear would be anywhere near as popular. The steam railway is a very popular and successful attraction. I and many others would...

The long-proposed Edginswell station is not intended to have car parking, though there is a line of 45 metered street parking spaces nearby along Newton Road, at £3.20 a day, so quite comparable to many smaller station parking charges. I think an advertised P&R would better rely mainly on the...

Maybe the case. The examples at Paignton were right outside the box so should have been a fairly easy pull anyway. Interesting idea. Might work well with double wire operated points, though the frames typically used for those in Europe have levers with a very long stroke of 180 degrees around a...

It was a mid to late 1980s scheme, so Exeter is approaching 40 years old, the usual threshold for starting to consider replacement, although when maintained in good order equipment can and often does last longer. While it's theoretically possible to life-extend relay based systems endlessly by...

An up passenger departure could not leave Paignton from platform 1 in the old layout either, as the left-hand crossover in the scissors had no facing point lock, and only an elevated shunt disc signal was provided for the movement. The lever frame at tiny Paignton North SB was full, with no...