Northbound Northern Line

[richardcoughla]

I notice today that trains from Archway going north are doing somthing odd when leaving they depart normally but as soon as they do they slow down almost to a stop and then depart as normal. Is there some sort of restriction or fault with the track if some sort?

 

[Daniel]

Yes, there is a temporary speed restriction over a set of points in the area. If you ride through the same area now you should notice the trains no longer accelerate then brake; they now depart at the slow speed throughout until beyond the issue.

 

[richardcoughla]

Yes, there is a temporary speed restriction over a set of points in the area. If you ride through the same area now you should notice the trains no longer accelerate then brake; they now depart at the slow speed throughout until beyond the issue.

Thanks I was thinking it was that but wasn't sure. I will take a ride during the weekend.

 

[alf]

I visited Golders Green recently & noticed on the return journey that there is a vicious speed limit north of Camden Town on the Southbound Edgware line into Camden Town.
It is probably 10 mph for over a quarter of a mile.

Trains used to barrel into Camden Town Station when I used the line before.

I spoke to a friend who said the same thing has happened on the southbound High Barnet branch into Camden Town.
Any one know why & is it permanent?

It adds to journey time & has non regular users for Camden Town standing uneasily by the doors for what seems an age before the train stops.

 

[Daniel]

I visited Golders Green recently & noticed on the return journey that there is a vicious speed limit north of Camden Town on the Southbound Edgware line into Camden Town.
It is probably 10 mph for over a quarter of a mile.

Trains used to barrel into Camden Town Station when I used the line before.

I spoke to a friend who said the same thing has happened on the southbound High Barnet branch into Camden Town.
Any one know why & is it permanent?

It adds to journey time & has non regular users for Camden Town standing uneasily by the doors for what seems an age before the train stops.

Yes - this is temporary - trains were being emergency braked on approach to Camden Town owing to a signalling issue. A TSR is in place to mitigate against this until the issue is fixed.

 

[alf]

Thanks Daniel.

I have just been rung by someone who says this TSR has been in place for three months.

It seems amazing that this issue has only come to light now when trains south bound into Camden Town have been racing into the two southbound platforms for about 100 years !
And without incident.

Added a few minutes later.

Sorry I did not read Daniel’s very helpful, & fast, reply properly

So the issue was that all southbound trains into CT were being emergency braked to a halt just north of CT platforms..on both branches.

And the temporary solution to stop the emergency braking was to alter the ATO to brake trains to below 10 mph north of the platforms?

What was the signalling issue that forced emergency braking to zero mph on both southbound branches?

Has it been found & why did it suddenly develop when ATO has been on the Northern line for years?

I hope someone’s answer will help me & others understand the complexities(or over simplifications!) of the Northern line automatic driving system.

To a layman it is less smooth & far less economical than the superb Vic line ATO system

 

[Taunton]

To a layman it is less smooth & far less economical than the superb Vic line ATO system

Jubilee is the same - power, coast, power, coast every few seconds. I think the Underground must have toyed with every auto driving system on the market over recent years. Among other things this means that suppliers are less willing to sort this type of issue out, because there is no long term relationship between them across the system.

 

[Daniel]

Thanks Daniel.

I have just been rung by someone who says this TSR has been in place for three months.

It seems amazing that this issue has only come to light now when trains south bound into Camden Town have been racing into the two southbound platforms for about 100 years !
And without incident.

Added a few minutes later.

Sorry I did not read Daniel’s very helpful, & fast, reply properly

So the issue was that all southbound trains into CT were being emergency braked to a halt just north of CT platforms..on both branches.

And the temporary solution to stop the emergency braking was to alter the ATO to brake trains to below 10 mph north of the platforms?

What was the signalling issue that forced emergency braking to zero mph on both southbound branches?

Has it been found & why did it suddenly develop when ATO has been on the Northern line for years?

I hope someone’s answer will help me & others understand the complexities(or over simplifications!) of the Northern line automatic driving system.

To a layman it is less smooth & far less economical than the superb Vic line ATO system

Hi - in short, it's to do with a system software upgrade associated with the Battersea extension. Obviously, something isn't working how it is intended but it fails safe, and those in control are doing what they can to minimise the impact on the service via the implementation of the TSR. This is not permanent and will, I understand, be rectified at some point in the future.

 

[Andy Orchard]

Hi - in short, it's to do with a system software upgrade associated with the Battersea extension. Obviously, something isn't working how it is intended but it fails safe, and those in control are doing what they can to minimise the impact on the service via the implementation of the TSR. This is not permanent and will, I understand, be rectified at some point in the future.

Over the past couple of months when approaching the points departing High Barnet platform 1 the train brakes sharply as well. I always select Protected Manual mode when departing from platform 1 because of this, so at least my passengers aren't subjected to being jolted about violently!

 

[alf]

Andy.
I had the weirdest ride on the TSR south into Camden Town from Golders Green at about 2pm today.

Train slowed to I0 mph normally & then max braked to a stop, restarted immediately & did the same violent brake to a stop twice more & then got into the platform.

We passengers would have had a peaceful ride if you had been up front & taking control!

 

[Andy Orchard]

Andy.
I had the weirdest ride on the TSR south into Camden Town from Golders Green at about 2pm today.

Train slowed to I0 mph normally & then max braked to a stop, restarted immediately & did the same violent brake to a stop twice more & then got into the platform.

We passengers would have had a peaceful ride if you had been up front & taking control!

Alf,

Thank you very much for the vote of confidence! Having driven the 1995 stock since new, I much preferred driving them conventionally! I also hate the way the 95s stop with a 'jolt' as well since we've had ATO on the Northern!

I guess I'm a bit of a 'dinosaur' who hates change!

Kind regards,

Andy

 

[Daniel]

Over the past couple of months when approaching the points departing High Barnet platform 1 the train brakes sharply as well. I always select Protected Manual mode when departing from platform 1 because of this, so at least my passengers aren't subjected to being jolted about violently!

You're right - there is another issue there too!!