Lewisham - Nunhead, why is so slow?

[hkstudent]

Southeastern get many destinations, and Victoria is the less loved one. Part of the reason is the longer journey time which sometime even Google Map saying chaning at London Bridge for Underground to Victoria is faster than a direct train from Lewisham.

By looking at the runtime, I am shocked that the 2km journey from Lewisham to Nunhead will take 7 minutes (no pathing), and 10.5 minutes from Nunhead (often to 12-13 mins due to congestion at Tanners Hill), I can even ride a bike faster than it.

Given that it's rather flat. What's the reason of such a slow journey?

 

[NSE]

You’ve kind of answered your own question. Congestion. Lewisham at one end (a notorious pinch point) and the flat at Nunhead on the other. Whilst the latter isn’t the busiest, it’s still carrying TL trains bound for the core which can have strict timings. Freight also goes across it. Add that all together and I guess that’s likely your answer.

 

[43066]

You’ve kind of answered your own question. Congestion. Lewisham at one end (a notorious pinch point) and the flat at Nunhead on the other. Whilst the latter isn’t the busiest, it’s still carrying TL trains bound for the core which can have strict timings. Freight also goes across it. Add that all together and I guess that’s likely your answer.

Yep. Busy junctions at each end, relatively low line speed (40mph IIRC) which is rarely reached due to encountering restricting aspects. Victoria and TBG signalling centres also overlap in this area, which possibly has an impact.

 

[hkstudent]

You’ve kind of answered your own question. Congestion. Lewisham at one end (a notorious pinch point) and the flat at Nunhead on the other. Whilst the latter isn’t the busiest, it’s still carrying TL trains bound for the core which can have strict timings. Freight also goes across it. Add that all together and I guess that’s likely your answer.

When I look at the westbound, there are no pathing added in respect of congestion. And often is both bounds train need to stop multiple times despite there are no trains on that track ahead.
Am thinking why can't it just reduce the runtime to run ahead of the train in conflict instead, given that it's exceptional slow, and with the same runtime, you would have reached London Bridge already.

 

[43066]

Am thinking why can't it just reduce the runtime to run ahead of the train in conflict instead, given that it's exceptional slow, and with the same runtime, you would have reached London Bridge already.

As noted above, lower line speed and restrictive aspects. Generous run times mean the service will be more robust.

 

[hkstudent]

To be fair, 4 minutes is more than enough for a westbound service. Even for the first Sunday service, SER has already planned a excessive 3 minutes actual dwell at Nunhead.

It's not acceptable in a metro area for trains to run 50% of speed of what it should achieve.

 

[30907]

To be fair, 4 minutes is more than enough for a westbound service. Even for the first Sunday service, SER has already planned a excessive 3 minutes actual dwell at Nunhead.

Your screenshot shows 1 minute booked (plus the train managed to beat the schedule, so 2min actual).

It's not acceptable in a metro area for trains to run 50% of speed of what it should achieve.

Could you perhaps show us your revised timings for weekday offpeak to demonstrate the possibility?

 

[ComUtoR]

It's not acceptable in a metro area for trains to run 50% of speed of what it should achieve.

Could you also provide details how how an 8 car Networker (they are typically Networkers through there) can achieve linespeed through there please.

 

[NSE]

From my understanding, a lot of drivers will drive lower than the line speed when they are on yellows and know there’s a red. For example, a driver might be able to take the train to line speed but they’re only going to sit outside Lewisham on a red, so therefore they trundle along at less than the line speed to avoid stopping and waiting at a red and then they’ll speed up once they’ve got a proceed. This gives the impression that there is a low line speed, when actually there isn’t, it’s just the driving style and the signals keeping it low.

 

[Islineclear3_1]

Might also have something to do with the original alignment/route between Nunhead and Greenwich Park before severance and a new diversion towards Lewisham added in the late 1920s...

 

[Grvrdvicdr]

Nunhead to Lewisham speeds: 25,20,60,20
Lewisham to nunhead speeds: 20,60,25

What I do as someone suggested is from Nunhead I tend to do no more than 20/25 as just wait at a red before Lewisham vale

From Lewisham it’s all signal dependent, sometimes can do it in 3 minutes or so on greens