West Coast Pendolino & Voyager retractioning?

[snowball]

I've heard suggestions that the North Wales Coast would remain served via the classic WCML.

There aren't likely to be any diesels or bi-modes on HS2, so the options for London to North Wales seem likely to be either serve it via the classic WCML, or change at Crewe.

 

[The Planner]

FWIW, a Mk3 set only lost I think 3 minutes between Euston and MKC over a Pendolino (timed at 30 mins, Pretendolino tended to take 33).

Which is effectively one path lost.

 

[driver_m]

Isn't that why the 110mph top speed (originally 100mph I think) of the TPE units wasn't considered an issue? They gain back in acceleration what they lose in top speed.

FWIW, a Mk3 set only lost I think 3 minutes between Euston and MKC over a Pendolino (timed at 30 mins, Pretendolino tended to take 33).

A pendo is timed 28m between Euston and MK non stop. Real world experience would still say that 110 units shouldn't be on the Fasts though. The great acceleration can be wiped out simply by not dispatching the unit at Euston quick enough, poor adhesion with fresh rain, reactionary delays elsewhere etc. There simply isn't the wiggle room in the current timetable, and that's before you consider the stuff that crosses over.

 

[Bletchleyite]

A pendo is timed 28m between Euston and MK non stop. Real world experience would still say that 110 units shouldn't be on the Fasts though

Without 110mph units on the fasts it would be impossible to operate the required commuter capacity at a reasonable speed[1] on the south WCML, simple as that.

[1] You could operate it just on the slows by running 12-car trains all stations (close Cheddington/Apsley/Kings Langley completely, stop serving Harrow/Bushey) on a 2 minute headway - but it would be rather unpopular.

 

[Chester1]

I've heard suggestions that the North Wales Coast would remain served via the classic WCML. They might shout, but possibly could be bought off by going hourly to Holyhead.

I very much doubt they will go hourly to Holyhead. They don't run past Chester for most of the day now. The WG obession with Holyhead to Cardiff services makes the obvious solution of Holyhead to Crewe services difficult. There will have to be a large amount of portion working in the next franchise to serve Crewe and Liverpool from the coast without a change. The business case for direct Holyhead to London services after 2027 will be poor because extra stops will need to be added south of Crewe and it will be much faster to change onto HS2.

Discontinuous electrification between Crewe and Chester to solve the problem of 34 bridges and putting batteries or small diesel generators in Pendolinos could have a reasonable cost. It would allow current Chester to London journey times to be maintained even with a couple of extra stops added and Chester will justify 9 or 11 coach units every hour. I suspect Holyhead services will be limited to 1 or 2tpd with a residual fleet of refurbished Voyagers.

 

[37057]

How much difference is there in the construction of the bogies on the 390s between those with motors and those without motors?

A 390 power bogie has a final drive gearbox on one axle. A trailer is the same but with an extra brake disc and caliper in place of the gearbox.... as far I remember anyway.

Slight variations amongst bogies with TPWS/AWS, TASS, WSP, speed probes and earth bonds etc.

Units 010 and 104 have track monitoring equipment added to a bogie on 688xx I think.

 

[The Planner]

Without 110mph units on the fasts it would be impossible to operate the required commuter capacity at a reasonable speed[1] on the south WCML, simple as that.

[1] You could operate it just on the slows by running 12-car trains all stations (close Cheddington/Apsley/Kings Langley completely, stop serving Harrow/Bushey) on a 2 minute headway - but it would be rather unpopular.

Not when the headway is 4 minutes on the slows you can't.

 

[Bletchleyite]

Not when the headway is 4 minutes on the slows you can't.

A 4 minute headway would probably deliver it too. But
I wouldn’t like a standard journey time of well over an hour and a half to Northampton.