• Our new ticketing site is now live! Using either this or the original site (both powered by TrainSplit) helps support the running of the forum with every ticket purchase! Find out more and ask any questions/give us feedback in this thread!

DRS order 10 'Class 88'

Status
Not open for further replies.

edwin_m

Veteran Member
Joined
21 Apr 2013
Messages
26,694
Location
Nottingham
These are almost certain to see off the Drs 20s, 37s, 47s, 57s and (who cares) 66s!

To replace the smaller classes the "last mile" engine would have to be able to get a flask train from Carnforth to Sellafield at a reasonable speed. That's a lot more than a mile.
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

HSTEd

Veteran Member
Joined
14 Jul 2011
Messages
18,627
To replace the smaller classes the "last mile" engine would have to be able to get a flask train from Carnforth to Sellafield at
a reasonable speed. That's a lot more than a mile.

700kW rated power makes them a type one of comparable power to a 20. Add in the modern traction pack and it should manage it easily.
 

hwl

Established Member
Joined
5 Feb 2012
Messages
7,633
700kW rated power makes them a type one of comparable power to a 20. Add in the modern traction pack and it should manage it easily.

Class 20
Power
Engine 1000HP (746kW)
At rail 770HP (574kW) i.e. 77% efficient
Tractive Effort
Max 187kn
Continuous 111kn

Compare with Class 88 figures
Engine 938hp (700kw)
At Rail ???
Tractive effort 317kn (Max presumably)

The difference in TE suggests it will be quite a bit more useful than a 20.
 

D365

Veteran Member
Joined
29 Jun 2012
Messages
12,154
700kW rated power makes them a type one of comparable power to a 20. Add in the modern traction pack and it should manage it easily.

Redundancy when off the electricity? Drag a 20 ;D
 

Beveridges

Established Member
Joined
8 Sep 2010
Messages
2,136
Location
BLACKPOOL
Flask work - slow, and very very light weight. Anything could do it. A single 20 powering the flasks would be overpowered compared to most freight trains today; which frequently are 2000+ tons with only a single 3000 horsepower engine at the front. 1000hp class 20 with a 200 ton flask train is still a far, far superior train performance wise than most freights of today. A 88 is comparable to a 20 so should cope effortlessly.
 
Last edited:

D365

Veteran Member
Joined
29 Jun 2012
Messages
12,154
The point is that two locomotive (systems) are required to provide redundancy, as you don't want to leave potentially dangerous goods out in the middle of nowhere. Even with a greater excess of power.
 

Murph

Member
Joined
16 Feb 2010
Messages
728
Flask work - slow, and very very light weight. Anything could do it. A single 20 powering the flasks would be overpowered compared to most freight trains today; which frequently are 2000+ tons with only a single 3000 horsepower engine at the front. 1000hp class 20 with a 200 ton flask train is still a far, far superior train performance wise than most freights of today. A 88 is comparable to a 20 so should cope effortlessly.

Is there not a rule that the flask trains must be double-headed to minimise the security risk of a flask being stationary behind a single failed loco in the middle of nowhere? Or do they just double-head due to the age or single-cab nature of the 20s?
 

D365

Veteran Member
Joined
29 Jun 2012
Messages
12,154
Is there not a rule that the flask trains must be double-headed to minimise the security risk of a flask being stationary behind a single failed loco in the middle of nowhere? Or do they just double-head due to the age or single-cab nature of the 20s?

Exactly right, as I posted just a moment ago. The ability to couple 20s nose-to-nose is just an additional benefit, not the main reason for this procedure being in place.
 

Murph

Member
Joined
16 Feb 2010
Messages
728
So, I suppose the remaining question is whether the 88s will be able to smash a parked Soviet tank out of the way, like a 20 can. ;)
 

HSTEd

Veteran Member
Joined
14 Jul 2011
Messages
18,627
So you could just run with a doubled up Class 88 and you would still be up compared to 2 Class 20s as you could have reduced maintenance bills and run of electricity as available.
 

edwin_m

Veteran Member
Joined
21 Apr 2013
Messages
26,694
Location
Nottingham
So you could just run with a doubled up Class 88 and you would still be up compared to 2 Class 20s as you could have reduced maintenance bills and run of electricity as available.

The costs of using two new and expensive 88s on a flask train would be far more than running two written-down class 20s. Maybe they will run the 88 with a 20 dead in train as backup?
 

D365

Veteran Member
Joined
29 Jun 2012
Messages
12,154
The costs of using two new and expensive 88s on a flask train would be far more than running two written-down class 20s. Maybe they will run the 88 with a 20 dead in train as backup?

Oii, that was my idea, hands off!


Ah yes...:lol:

[Armoured Russian Class 20 vs tank, GoldenEye]

The front of that beast looks like one of the Easter Island statues! Shame the actual loco sounds were dubbed over though...
 
Last edited:

themiller

Established Member
Joined
4 Dec 2011
Messages
1,225
Location
Cumbria, UK
Is there not a rule that the flask trains must be double-headed to minimise the security risk of a flask being stationary behind a single failed loco in the middle of nowhere? Or do they just double-head due to the age or single-cab nature of the 20s?

I seem to remember that, when DRS first started up EWS were quoted as saying that they would not rescue a failed flask train. This may be why DRS normally double head/top-and-tail but I have seen a single loco on flasks before. With brand new locos, there could be a justification for single heading particularly as DRS are now a national operator.
 

Freightmaster

Established Member
Joined
7 Jul 2009
Messages
3,816
I seem to remember that, when DRS first started up EWS were quoted as saying that they would not rescue a failed flask train. This may be why DRS normally double head/top-and-tail but I have seen a single loco on flasks before. With brand new locos, there could be a justification for single heading particularly as DRS are now a national operator.
It's an urban myth that flask trains must be double headed because
of some arcane rule...

AFAIK, DRS double head them simply to be "better safe than sorry" in
the event of a loco failure, especially as most power stations served
are a long way from Crewe/Carlisle.

MARK
 

Loki

Member
Joined
24 May 2013
Messages
151
Location
West Midlands
Class 88 from railwaygazette.

tn_gb-drs-class88-vossloh-eurodual-locomotive-impression.jpg
 

route:oxford

Established Member
Joined
1 Nov 2008
Messages
4,949
Now that looks quite splendid.

Is there anywhere on the network where it could operate push-pull with both pantographs up and 10 (power door) Mk3s in between?
 

WatcherZero

Established Member
Joined
25 Feb 2010
Messages
10,272
Could manage 9 in between on most of the West Coast, anywhere 11 coach Pendolinos went.
 

Loki

Member
Joined
24 May 2013
Messages
151
Location
West Midlands
Now that looks quite splendid.

Is there anywhere on the network where it could operate push-pull with both pantographs up and 10 (power door) Mk3s in between?

It would be interesting to know if it could operate on catenary and diesel at the same time for extra boost.
 

Murph

Member
Joined
16 Feb 2010
Messages
728
It would be interesting to know if it could operate on catenary and diesel at the same time for extra boost.

Wouldn't it be rather surprising if it was running the traction motors at less than 100% of their capability when on OHLE (when max power is requested by the driver, and there's no wheel-slip)? Unless there's some reason why it can't go to 100% from OHLE alone, it would not be possible to get any "boost" by running the diesel generator at the same time, without damaging/destroying the motors. You'd also likely need much more complex and expensive control / load sharing gear, rather than a relatively simple A/B contactor set (or equivalent).
 

edwin_m

Veteran Member
Joined
21 Apr 2013
Messages
26,694
Location
Nottingham
Electrics already usually have the ability to exceed their continuous power rating for a short period, for example when accelerating.
 

Murph

Member
Joined
16 Feb 2010
Messages
728
Another thought on the 68s and 88s, and their ability to retire some of EE's wonderful creations. Is there any word on what route availability is expected for them? The 20s and 37s (not all sub-classes) are both the go almost-anywhere RA5. Is that likely to still be a significant factor these days?
 

route:oxford

Established Member
Joined
1 Nov 2008
Messages
4,949
Wouldn't it be rather surprising if it was running the traction motors at less than 100% of their capability when on OHLE (when max power is requested by the driver, and there's no wheel-slip)? Unless there's some reason why it can't go to 100% from OHLE alone, it would not be possible to get any "boost" by running the diesel generator at the same time, without damaging/destroying the motors. You'd also likely need much more complex and expensive control / load sharing gear, rather than a relatively simple A/B contactor set (or equivalent).

Even in push-pull mode with the pulling loco on electric and push loco on diesel?


I'm sure it was managed in the olden days when HSTs were pressed into service as DVTs.
 

ash39

Established Member
Joined
8 Feb 2012
Messages
1,506
The point murph made was that both the diesel engine and electricity from the pantograph will be powering the same traction motors so there'd be no benefit to running both at the same time. It would either make no difference at all, or knack the traction equipment. Likelihood is the loco won't allow it to be done anyhow.

Not sure what the benefit of that would be route:oxford? If you really wanted to do it, why not run both off the OLE rather than one on diesel. When it was done on the ECML with HSTs they were never originally intended to power the train but iirc it wasn't good for the engines idling continuously so they tweaked the arrangement to let them apply traction.
 

route:oxford

Established Member
Joined
1 Nov 2008
Messages
4,949
The point murph made was that both the diesel engine and electricity from the pantograph will be powering the same traction motors so there'd be no benefit to running both at the same time. It would either make no difference at all, or knack the traction equipment. Likelihood is the loco won't allow it to be done anyhow.

Not sure what the benefit of that would be route:oxford? If you really wanted to do it, why not run both off the OLE rather than one on diesel. When it was done on the ECML with HSTs they were never originally intended to power the train but iirc it wasn't good for the engines idling continuously so they tweaked the arrangement to let them apply traction.

I was unsure of the current restrictions running two electric locos in push-pull mode at speed.

It doesn't seem that long since commetators expressed concern about the wave patterns at the second pantograph bringing down the knitting.
 

HSTEd

Veteran Member
Joined
14 Jul 2011
Messages
18,627
Not a problem on the ECML when the NOL sets were eventually authorised to run at 125mph on significant stretches.
 

WatcherZero

Established Member
Joined
25 Feb 2010
Messages
10,272
Theres a powergraph of the 88's in UK Railways mag, not unsurprisingly the 4mw under the wires performs a lot better than the 700kw diesel only which really trails off after around 50mph.

Answers one question I had on how much fuel capacity would be lost to electrical equipment as they are using the same bodyshell as the 68's, states they will have 2,500 litre tanks which compares with 4,000 for the standard Eurolight and 5,000 for the UK specific Class 68.
 
Last edited:
Status
Not open for further replies.

Top