London to Norwich - 90 min timings

[dk1]

Maybe the ability to use 10,000hp instead of only 5,000 giving the train better acceleration...

It doesn't work like that. The rear loco would be shut down & nothing more than a dead weight.

 

[dk1]

Actually if a 755 is not available - a 360 should be substituted to take its place instead as the 360s are the only trains with the performance spec to do the job reliably. 100mph from rest in 2.5 mins!!

Would cause crewing headaches. No ex-Anglia drivers or conductors sign class 360s & no Great Eastern drivers sign North of Haughley Jcn. There are also no spare 360s in the fleet to cover.

 

[Railperf]

It doesn't work like that. The rear loco would be shut down & nothing more than a dead weight.

In normal service that is usually the case. But
I'm sure i was told reliably that it is technically possible to have both locos powered that way - id both are TDM fitted - and controlled by the leading loco unless there are specific restrictions on the route prohibiting that. In the same way you can double head a train with 2 electric locos and both be providing traction power.

 

[Railperf]

Would cause crewing headaches. No ex-Anglia drivers or conductors sign class 360s & no Great Eastern drivers sign North of Haughley Jcn. There are also no spare 360s in the fleet to cover.

That's a pity!! So we need a shorter MK3 set and loco then! Is the plan to roster a single 755 as these are only 4 - car?

 

[dk1]

In normal service that is usually the case. But
I'm sure i was told reliably that it is technically possible to have both locos powered that way - id both are TDM fitted - and controlled by the leading loco unless there are specific restrictions on the route prohibiting that. In the same way you can double head a train with 2 electric locos and both be providing traction power.

This would be in normal service & not permitted. Freightliner are trialing the use of two 90s on certain Ipswich trains to replace the pairs of 86s but even then each 90 has to have a traction motor isolated. You would gain nothing on an IC set even if this was allowed & running a slightly shorter set with the DVT which would also need to be in the formation would be the sensible option.

 

[dk1]

That's a pity!! So we need a shorter MK3 set and loco then! Is the plan to roster a single 755 as these are only 4 - car?

There will be 3 & 4 car 755s by Summer hopefully & the plan is to run them in pairs.

 

[Railperf]

I doubt 321's would be used, using a 90 set on the 90 timing and then the 321 on the next service to make use of the acceleration advantage would make more sense?

There's no real advantage using a 321 over a 90 acceleration wise. The 321 is quicker 0-60, but the Class 90 is better at the upper speed range 60-100mph. In the end a Class 90 hauled set (with all traction motors working and a dry rail) would clawback any deficit lost at the lower end. But neither beats a 360 - which is around 30 secs quicker over 4 or 5 miles!

 

[Railperf]

They lose too much through neutral sections. Also not exactly reliable north of Ipswich dependant upon NR infrastructure and 3rd no drivers or conductors have both route and traction knowledge for the whole route.

I've recorded train performance extensively on this route, and the 360's don't lose any significant time over a Class 90 IC set or a pair or triple Class 321 sets through Neutral sections. That's why 360's hold most fastest times between stations on the GEML - including those that have a Neutral section a short distance from the station such as Witham, Colchester, Shenfield and Manningtree.

regarding crewing - wouldn't it make sense to train those GE drivers who go as far as Haugley to sign the last piece of route to Norwich? The 360's were given clearance to run to Norwich some years back. Would they need conductors?

 

[dk1]

I've recorded train performance extensively on this route, and the 360's don't lose any significant time over a Class 90 IC set or a pair or triple Class 321 sets through Neutral sections. That's why 360's hold most fastest times between stations on the GEML - including those that have a Neutral section a short distance from the station such as Witham, Colchester, Shenfield and Manningtree.

regarding crewing - wouldn't it make sense to train those GE drivers who go as far as Haugley to sign the last piece of route to Norwich? The 360's were given clearance to run to Norwich some years back. Would they need conductors?

Yes they would need conductors. Getting agreement from drivers unions for this would most proberbly if not certainly be rejected from the outset so as such short term would not be considered.

 

[306024]

Simple answer is that it would make no sense to train the Peterborough link at Colchester, and the conductors required, for such an adventure. Although you rarely get trains cancelled for no crew, GA is not awash with drivers and trainers that can be released for such a short term issue. The cost would be excessive.

 

[Trainfan344]

Has a 755 made it to Liverpool Street yet? I've seen pictures as far south as Diss but no more than that!

 

[TheEdge]

Has a 755 made it to Liverpool Street yet? I've seen pictures as far south as Diss but no more than that!

Under their own power I believe Colchester is the furthest they've gone. Obviously on their delivery drags they've covered Stratford to Colchester.

Not sure what they've achieved on the WAML.

 

[brad465]

If the introduction of the service and 755s goes to plan I maybe able to take advantage when I go to a cycle event in Norfolk in mid-June this year. Hopefully the bike reservation/storage capability won't be an issue, if anyone has clarity on this?

 

[306024]

Look at the cycle policy on the GA website. You’ll have to book in advance and spaces are limited.

Looking at Real-time trains it seems Norwich in 90 has been made easier by down trains travelling back in time between Lakenham and Trowse Jn, unless GA have ordered a fleet of TARDISes. Or it could just be the offset for Lakenham, which isn’t an official timing point, is wrong.

 

[louis97]

Or it could just be the offset for Lakenham, which isn’t an official timing point, is wrong.

Thank you for mentioning that, whilst the offset was correct it was setup with the incorrect berth step. This will be corrected very soon. Trowse Lakenham Junction is an official timing point, it is mandatory in the up direction for trains travelling over the down line from Trowse Junction and returning to the up line at Lakenham Junction.

 

[306024]

You’re welcome, didn’t think anyone would pick up on it so thanks. Struck me as odd when looking at the East Anglian down tonight and then found it in other schedules. Yes should have said not normally a timing point. Quite rare for trains to be planned that route although it is used in practice to allow something off the Thetford road to keep going a bit further.

 

[louis97]

You’re welcome, didn’t think anyone would pick up on it so thanks. Struck me as odd when looking at the East Anglian down tonight and then found it in other schedules. Yes should have said not normally a timing point. Quite rare for trains to be planned that route although it is used in practice to allow something off the Thetford road to keep going a bit further.

If you do spot anything else please feel free to PM me or email [email protected]

The 1500 Norwich to Liverpool Street on at least a Monday to Friday is booked to do that move, rarely does it though if I recall correctly.

 

[Adrian1980uk]

Is the actual train really significant here because I suspect its the pathing that's always been the issue and theres no real reason why a ic90 set couldn't do it

 

[Alfie1014]

I see looking at RTT that the retimed 17:02 down and 07:40 up Norwich serivces last week managed to equal or better the accelerated schedules on all but one occasion. And at least one up and three down managed the journey in 1 hour and 38 minutes. So pretty close to the 'magical' 1hr 30 mins.

Also I note that the new 11:00 down not only requires the 10:30 to get to Norwich on time in front of it but also the Parkeston - North Walsham condensate tanks (on the days it runs) to be on time too as this is only 5 mins in front of the 10:30 over Trowse Swing Bridge!

 

[Trainfan344]

Rumours spread on Thursday about Class 68s being hired in for this service...

 

[captainbigun]

Must’ve been a slow news day.

No idea who dreams these things up.

 

[JonathanH]

Rumours spread on Thursday about Class 68s being hired in for this service...

Is a class 68 going to beat the performance of a class 90?

 

[hexagon789]

Is a class 68 going to beat the performance of a class 90?

Even allowing for the fact a 90 is geared for 110mph, I doubt it. A 90 can produce up to 7,860hp; a 68 has a maximum at-rail output of 2,400kW (3,218hp).

Surely a 68 can't best a 90 based on that?

 

[Class 170101]

Surely that should read Class 88 vice Class 68?

 

[Trainfan344]

No, the rumour was 68s. I'm not sure where it came from, but I sincerely doubt it.

 

[Railperf]

Even allowing for the fact a 90 is geared for 110mph, I doubt it. A 90 can produce up to 7,860hp; a 68 has a maximum at-rail output of 2,400kW (3,218hp).

Surely a 68 can't best a 90 based on that?

Compare the performance of a Class 90 with load 10 and a Class 68 on Load 7 and see what you think is quicker?
First the '90'

then the '68'

 

[Alfie1014]

Compare the performance of a Class 90 with load 10 and a Class 68 on Load 7 and see what you think is quicker?
First the '90'

then the '68'

Interesting but not a direct comparison. The 68 has level or falling gradients for the first couple of miles out of High Wycombe, whereas the 90 faces rising gradients after the first half a mile, stiffening to 1 in 131 on the climb up to and beyond to Haughley Junction.

 

[Railperf]

Interesting but not a direct comparison. The 68 has level or falling gradients for the first couple of miles out of High Wycombe, whereas the 90 faces rising gradients after the first half a mile, stiffening to 1 in 131 on the climb up to and beyond to Haughley Junction.

Yes. That is right. A direct comparison isn't possible...but the fact the 68 with a lighter load going downhill accelerating slower than a 90 with a heavier load going uphill pretty much says it all.

 

[hexagon789]

Compare the performance of a Class 90 with load 10 and a Class 68 on Load 7 and see what you think is quicker?
First the '90'

then the '68'

Neither are as quick as I believe they can be.

 

[Railperf]

Neither are as quick as I believe they can be.

The Class 68 driver told me that apart from the initial start..it was on full power and no perceived wheelslip. The 90 run - as noted by another member starts uphill and gets steeper hence the slowing acceleration rate. I have seen a 90 get to 100mph from Ipswich northbound in just over 3 mins and 3.5 miles on a dry rail.
You could spend a day recording these and no two runs would ever be the same. An extra coach or 2 blunts performance - as does a traction motor out. And if it rains - it may never even reach 100mph between some station stops.
That's why the 745's should be better - performance wise. They offer distributed traction - more powered wheels and a consistent performance in wet and dry.