GEML Unusual Engineering Block - sometime in the summer of 2017

[700007]

A really weird thought popped into my mind and I am quite sure that I am not making this up, but alas I don't have any proof or evidence to prove that it happened.

I remember one weekend and I don't believe it has been repeated since, sometime in the spring or summer of 2017 where there was a planned block of the electric lines only I think between Chadwell Heath and Gidea Park. All TfL Rail trains terminated at Chadwell Heath from London Liverpool Street but instead of buses being put on, Greater Anglia had trains all day at frequent intervals doing Stratford to Chadwell Heath non-stop, then all stations to I think it was a combination of either Braintree or Southend Vic.

What was the reasoning for this to happen that particular weekend? Would it ever happen again in a similar context? What was the exact service pattern in use that weekend?

Thank you to anyone who can assist or at least confirm I didn't make this up in my mind!

 

[rheingold103]

Something is familiar here, but I may be well off target in thinking of planned coasting (pan down) for OLE supply work. Some classes could be used but others not because of eg. auxiliaries/ battery supply. Station stops were skipped for obvious reason.

 

[dk1]

Something is familiar here, but I may be well off target in thinking of planned coasting (pan down) for OLE supply work. Some classes could be used but others not because of eg. auxiliaries/ battery supply. Station stops were skipped for obvious reason.

I recall that around the Romford to Chadwell Heath section. Didn’t the EMUs have to be 12-car or something? If that was the case they wouldn’t be able to stop at any stations between Brentwood & Maryland inclusive.

I also recall that 360s couldn’t be used incase of stranding. Didn’t all pans shut down when any part of the formation was in a neutral section?

 

[Class 170101]

Sounds like coasting. The more modern stock being too clever by half to coast. The 321s being a simplier technology and so less to go wrong in a no power section.

 

[rheingold103]

We had to have a clear run on greens throughout, accelerate to line speed, lower pantographs, and some faith in reaching live OLE before coming to a stand. Indeed, 360s were not used as 'too clever' to run the distance and re-raise their pans.
On further thought, this was over the falling gradient Up Electric line which was BTET* because of trackwork on the adjacent but generously spaced Main lines. The Down Electric was live for returning traffic.
@700007 is this thread 'on the right line'?
*BTET = Blocked to Electric Traction

 

[Bricktop]

Something is familiar here, but I may be well off target in thinking of planned coasting (pan down) for OLE supply work. Some classes could be used but others not because of eg. auxiliaries/ battery supply. Station stops were skipped for obvious reason.

A really weird thought popped into my mind and I am quite sure that I am not making this up, but alas I don't have any proof or evidence to prove that it happened.

I remember one weekend and I don't believe it has been repeated since, sometime in the spring or summer of 2017 where there was a planned block of the electric lines only I think between Chadwell Heath and Gidea Park. All TfL Rail trains terminated at Chadwell Heath from London Liverpool Street but instead of buses being put on, Greater Anglia had trains all day at frequent intervals doing Stratford to Chadwell Heath non-stop, then all stations to I think it was a combination of either Braintree or Southend Vic.

What was the reasoning for this to happen that particular weekend? Would it ever happen again in a similar context? What was the exact service pattern in use that weekend?

Thank you to anyone who can assist or at least confirm I didn't make this up in my mind!

No you wasn't wrong. The person who developed the coasting was myself, Gary Desmond, a Project manager for NWR's OCR team. This required a 2 Line possession and a 3 line Isolation.
I worked closely with NWR and Greater Anglia to devise a method of working The GE OLE was being renewed but 4 track access had been declined from just before the Olympics until around 2015. We managed to deliver outside wire runs with 2 track access but eventually had to try and get inside wire runs completed. We undertook coasting on 12 occasions along the GEML, the first run was a trial to see if we could deliver inside overhead line renewals between Romford And Chadwell Heath back in 2013. The Pantograph were lowered at Crowlands NS and the trains coasted over the Up Electric to Ilford Stn to a stand still and the pans were raised. We used Class 321's because these didn't appear to lose air while coasting, plus we did about 6 weeks worth of trial runs on a Fri night along the GEML to see what we could do and where we could do it and from.
The last trial run undertaken was from Shenfield on the Up Electric. We lowered the pan just London side of Woodway Bridge at Shenfield and then ran towards London, The train coasted through Gidea Park and applied the brake at the correct speed limits and also over Ilford flyover. We arrived in Stratford Stn and only stopped there because there was a possession between Stratford and London Liverpool Street, otherwise the train would have gone all the way, Lost hardly any air and the coasting distance was just shy of 15 miles!

The Up Electric worked as the gradient makes it quite easy, but we also undertook 2 wire runs on the Up Electric with Trains coasting over the Down Main from Ilford TSC to Romford Stn and Romford TSC to Harold Wood Stn with a raising gradient.

The first run was done in 2013, then from 2015 until the last one in 2017, 12 in total