Class 484 replacing class 483 on the island line: progress updates

[spark001uk]

It's not just the height though is it, it's the curves, as pointed out recently (again).

 

[KendalKing]

It's not just the height though is it, it's the curves, as pointed out recently (again).

Hence, why I included the lengths.

 

[spark001uk]

Hence, why I included the lengths.

Ok. It's titled height comparison, so I thought that's what you were highlighting.

 

[KendalKing]

Ok. It's titled height comparison, so I thought that's what you were highlighting.

Sorry, should made it clearer, that it was both.

 

[Jan Mayen]

I wonder if it's worth, or even possible, to attach a single carriage to a road railer or other vehicle, and push the carriage through to prove it works.
Make sure there are press photographers on Esplanade platform to take photos of the undamaged carriage.

Obviously, an unpublicised dress rehearsal in the early hours of a dark night might be a good idea, just in case..

(I remember when BR showed off a wheelchair accessible coach, only to find the wheelchair didn't fit).

 

[zwk500]

I wonder if it's worth, or even possible, to attach a single carriage to a road railer or other vehicle, and push the carriage through to prove it works.
Make sure there are press photographers on Esplanade platform to take photos of the undamaged carriage.

Obviously, an unpublicised dress rehearsal in the early hours of a dark night might be a good idea, just in case..

(I remember when BR showed off a wheelchair accessible coach, only to find the wheelchair didn't fit).

We have computers for this kind of thing now. Take a 3D laser scan of the tunnel, and a 3D laser scan of the train in the depot. Put the two together in the computer and it'll tell you down to a fraction of a millimetre what the clearance is. Much simpler, much safer, and much cheaper if the answer's not what you were hoping for! Just make sure you've cleared any shrubbery away from the tunnel mouth when the laser starts...

 

[david1212]

It's been suggested that the power supply - though undeniably flaky - could still have allowed longer trains if sufficient units were available, certainly the comments by Chris Garnett about voltage drop were debunked.

I read somewhere late last year that Mark Hopwood had asked if a 4-car set could be run on the last weekend. Once 008 was sidelined there was no possibility as 007 could not run in multiple.

I've not seen much evidence of 6-car trains, but it seems the spare driving motor made 3TIS+3TIS+DM quite a regular sight.

Back to the 485 / 486 sets indeed over time numerous combinations. While it did happen the 3TIS sets were not intended to run alone e.g. linked photo 1 & linked photo 2 from this website page .

In asking about 6-car trains I was thinking of the 483's though. The answer may well be no based on this reply

I'm not sure 3-set trains ever did operate. In any case, it would have caused problems at Lake, where the platform is only 5 cars long (most 485/486 trains operated in 5 car sets in their last few years).

A 4-car 483 would nominally have the same capacity as a 5-car 485/486 with two Driving motors and three trailers. The fact that an active fleet of eighteen 483 cars replaced fourty-three 485/486's shows the decline in demand in just over twenty years. Now thirty years later ten 484 cars are replacing the 483's.

 

[Journeyman]

I read somewhere late last year that Mark Hopwood had asked if a 4-car set could be run on the last weekend. Once 008 was sidelined there was no possibility as 007 could not run in multiple.



Back to the 485 / 486 sets indeed over time numerous combinations. While it did happen the 3TIS sets were not intended to run alone e.g. linked photo 1 & linked photo 2 from this website page .

In asking about 6-car trains I was thinking of the 483's though. The answer may well be no based on this reply


A 4-car 483 would nominally have the same capacity as a 5-car 485/486 with two Driving motors and three trailers. The fact that an active fleet of eighteen 483 cars replaced fourty-three 485/486's shows the decline in demand in just over twenty years. Now thirty years later ten 484 cars are replacing the 483's.

There were far less than 43 485/6 cars left by the time the 483s appeared. The fleet was probably not much more than 20 cars by that time.

 

[Chris125]

We have computers for this kind of thing now. Take a 3D laser scan of the tunnel, and a 3D laser scan of the train in the depot. Put the two together in the computer and it'll tell you down to a fraction of a millimetre what the clearance is. Much simpler, much safer, and much cheaper if the answer's not what you were hoping for! Just make sure you've cleared any shrubbery away from the tunnel mouth when the laser starts...

While that's true for something static, gauging must also allow for trains to move around especially when negotiating sharp curves at speed on ballasted track like Esplanade Tunnel - as modern gauging has a reputation for being quite conservative one wonders if this has tripped up Vivarail.

In asking about 6-car trains I was thinking of the 483's though. The answer may well be no based on this reply

It's been said there was a 6-car test run when they arrived, otherwise only in emergencies.

As for fleet size, while traffic has obviously seen a decline much of the change is down to travel patterns and greater efficiency - in the early years demand was still concentrated on a few summer saturdays when vast numbers would descend for their week long holiday, yet the winter service was only hourly. With visitor demand far less concentrated and a dedicated pier shuttle service they could shrink the fleet considerably.

NSE did bring over plenty of units but I've never seen an explanation why, a 20min service of 4-car trains would surely have proved extravagant and that fleet was soon downsized too.

 

[zwk500]

While that's true for something static, gauging must also allow for trains to move around especially when negotiating sharp curves at speed on ballasted track like Esplanade Tunnel - as modern gauging has a reputation for being quite conservative one wonders if this has tripped up Vivarail.

The gauging systems I've seen results from account for the kinematic envelope and profile. That and a table of tolerance applied by the engineer. The computer will only output the clearances - it doesn't specify the speeds, that's the engineers job.

 

[Chris125]

The gauging systems I've seen results from account for the kinematic envelope and profile. That and a table of tolerance applied by the engineer. The computer will only output the clearances - it doesn't specify the speeds, that's the engineers job.

Of course, but it's those tolerances that allow for the vehicle moving around and the data/assumptions behind them which could be the difference in this case.

 

[zwk500]

Of course, but it's those tolerances that allow for the vehicle moving around and the data/assumptions behind them which could be the difference in this case.

Indeed - but there's nothing you'd get from pushing a unit through at less than walking you won't get from a computer, which is what my response was saying. If you wanted to test the kinematic profile with a live unit, you'd need to arrange for it to go through at linespeed. And given it's a single bore tunnel, good luck convincing an engineer to stand in front of the unit with a torch to check how close it gets!

 

[spark001uk]

I was half expecting they'd have put a RILA scanner or similar through the tunnel at some point, but I'm not sure (in the RILA's case at least) if it would mount onto a 483? Fugro do say the latest device will fit "any passenger train", but I fear they may not have necessarily had 83yr old tube stock in mind.!

 

[zwk500]

I was half expecting they'd have put a RILA scanner or similar through the tunnel at some point, but I'm not sure (in the RILA's case at least) if it would mount onto a 483? Fugro do say the latest device will fit "any passenger train", but I fear they may not have necessarily had 83yr old tube stock in mind.!

I would have thought it would be better value for money to just pay a surveyor to do it from a tripod-mounted scanner.

 

[spark001uk]

I would have thought it would be better value for money to just pay a surveyor to do it from a tripod-mounted scanner.

I was thinking along the lines of the kinematics being measured from a moving unit.
What's the current line speed through the tunnel?

 

[Trackman]

I was thinking along the lines of the kinematics being measured from a moving unit.
What's the current line speed through the tunnel?

20, then at St Johns road goes up to 45 I think.

 

[Chris125]

Indeed - but there's nothing you'd get from pushing a unit through at less than walking you won't get from a computer, which is what my response was saying. If you wanted to test the kinematic profile with a live unit, you'd need to arrange for it to go through at linespeed. And given it's a single bore tunnel, good luck convincing an engineer to stand in front of the unit with a torch to check how close it gets!

True, though modern gauging software has been criticised for being more conservative than more traditional methods - there was a good article in Rail Engineer a few years back:

"However, when (Network Rail’s) National Gauging Database was introduced, it became clear that some rolling stock was running in locations where clearances were indicated to be sub-standard or foul. The accident free history of the running of such rolling stock indicated that this was not likely to be a true clearance issue, but one of conservatism in the calculations. More detailed examination revealed the origin of such conservatism as being in the tolerances that are routinely applied as part of the gauging process."

I was half expecting they'd have put a RILA scanner or similar through the tunnel at some point, but I'm not sure (in the RILA's case at least) if it would mount onto a 483? Fugro do say the latest device will fit "any passenger train", but I fear they may not have necessarily had 83yr old tube stock in mind.!

I think there was confirmation of such a scan on twitter back when the 484s were first announced, though I doubt it went through attached to a 483 - a hand pushed trolley overnight would seem more likely!

 

[zwk500]

True, though modern gauging software has been criticised for being more conservative than more traditional methods - there was a good article in Rail Engineer a few years back:

"However, when (Network Rail’s) National Gauging Database was introduced, it became clear that some rolling stock was running in locations where clearances were indicated to be sub-standard or foul. The accident free history of the running of such rolling stock indicated that this was not likely to be a true clearance issue, but one of conservatism in the calculations. More detailed examination revealed the origin of such conservatism as being in the tolerances that are routinely applied as part of the gauging process."

My bold. This suggests the fault lies with the engineers, not the software.

FWIW, the gauging database does have what's known as 'creep', so the older the data is the wider the envelope is presumed to be. However, these are usually pretty easy to spot when off and easily resolved by running the gauging train through the area concerned. If the system has recent data, it's pretty good. Although there have been strange restrictions from random brambles or the like from time to time.

 

[Chris125]

Have they turned the power back on at Ryde? 001 has been seen moving outside Ryde works on the siding where 009 and 008(?) had been stabled.

https://www.facebook.com/IslandEcho/videos/243398137438122/

 

[swt_passenger]

Have they turned the power back on at Ryde? 001 has been seen moving outside Ryde works on the siding where 009 and 008(?) had been stabled.

https://www.facebook.com/IslandEcho/videos/243398137438122/

I wonder if the sidings and P3 can be independent switched on or off?
Did you see the ridiculous comments? It’s allegedly being “pulled along”...

 

[Trackman]

I wonder if the sidings and P3 can be independent switched on or off?
Did you see the ridiculous comments? It’s allegedly being “pulled along”...

It could also be something to do with DC switchgear they are replacing (or even by now replaced) at Ryde St Johns.

 

[fgwrich]

I wonder if the sidings and P3 can be independent switched on or off?
Did you see the ridiculous comments? It’s allegedly being “pulled along”...

I did. And I thought I'd seen enough stupid comments on the internet this week (bangs head).

Could it also be moving under battery power?

 

[Journeyman]

I did. And I thought I'd seen enough stupid comments on the internet this week (bangs head).

Could it also be moving under battery power?

It was fitted with batteries in the saloon for initial tests on the mainland, so possibly.

 

[Chris125]

Driver familiarisation according to a comment on facebook.

While 001 can move using a battery, it wouldn't explain how the two 483s were moved out of the way.

 

[Bob Price]

A tweet from Island Echo shows 001 moving about the yard at St John's rd

https://twitter.com/islandecho/status/1370407129186713605?s=19

 

[Chris125]

I hope Vivarail have got the dwell times sorted with these, realtimestrains shows the new half hourly service from May 16th and they only get 4mins at Pier Head...

 

[Dstock7080]

I hope Vivarail have got the dwell times sorted with these, realtimestrains shows the new half hourly service from May 16th and they only get 4mins at Pier Head...

No need to fully charge the train line and air auxiliaries as on 483s, just keys in, radio setup, check signal and go!
Regularly did 4min turnaround with 6-car D Stock.

 

[philthetube]

dwell times not Vivarail's problem, SWT knew what they are buying and if not suited for purpose then down to them.

 

[Fincra5]

I hope Vivarail have got the dwell times sorted with these, realtimestrains shows the new half hourly service from May 16th and they only get 4mins at Pier Head...

A 4 Min Turn around is common, 1 Min to shut the cab down, 1 Min Walking, 2 Mins to prepare the cab...

 

[mackeral1234]

Better manage it I’d there was a extra driver at Pier to jump in and get it ready… like Waterloo & City used to be.