HST-Dft proposes life extension!

[whole diary]

[devon_metro]

In all major HST^▸ (High Speed Train) accidents I believe the Mk3 buffet has been folded or crushed, whereas there was only minor damage to the pendolino, however a train with the restrictive interior of a pendolino would not be a better replacement to the Mk3, and to some extent this is the reason they are so strong, due to the numerous structural support - of which the FGW^▸ (First Great Western) mk3s have none.

[Electric train]

The weakness of the Mk3 compared to Pendolino is the buckeye, the buckeye is a good coupling but not as Strong as the bolted flange type which I believe the Pendolino use. 

Whether it is cost effective to modify the Mk3's to have plugin type doors is questionable.  The real choice is with the ETH supply and control cabling, if the HSDT^▸ (Original name for High Speed Train) Mk3's were rewired with the standard single phase 850 volt ETH, this would require a motoraltenator to be fitted to each coach, this would increase the flexibility of. IF the TOC^▸ (Train Operating Company)'s FOC^▸ (Freight Operating Company)'s and train leasing companies could agree a standard form of train control this again increase the flexibility of use.

It goes with out saying that retention toilets are a must but this could reduce the number of toilets on the train to one per coach.

[RichieG]

Build new HSTs^▸ (High Speed Train)?

Not IEP^▸ (Intercity Express Program / Project.) or anything like that, just a new fleet of good old fashioned Class 43 HSTs.

Some changes to the original design would need to be made, such as the what engine is used (after all, spending ^x in upgrading from the Valentas to MTUs^▸ (Motor Traction Unit) would be silly if new ones were made with Valenta engines!) and I'm sure that there have been a number of other things that have been added to the original design of the locos since their original manufacture.

I believe (but will be happy to be corrected!) that structurally the MK3 coaches are fine to a certain extent so just a load more would need to be made, perhaps with automatic doors (or at the very least, doors which can be opened from the inside! As an aside, I've noticed many times that there is a metal plate screwed on to the doors on the insides where the handle is; why can't they put handles on the inside as well as the outside?) I believe that New Zealand have a few MK2 coaches and have adapted them to automatic doors so would assume that we could create MK3s with automatic doors fairly simply. The seating arrangements of the carriages would need a bit of work from the FGW^▸ (First Great Western) standard, but as each TOC^▸ (Train Operating Company) has upgraded their MK3s differently that's a bit of a by-point.

(I will point that I am not by any means all that knowledgeable of the actual structure of stock so the above suggestions might - and probably will - be exceptionally wrong.

[IndustryInsider]

Build new HSTs^▸ (High Speed Train)?

Far too many safety regulations since the mid-70's to make that worth considering. You might as well start out from scratch than try and make a 40 year old design meet modern safety standards. By all means keep the same principal of the design though, i.e. engines separated from carriages.

[eightf48544]

The Wessex units were basically mostly mark 3 with power doors.

[JayMac]

I believe eightf was referring to the Class 442 (5WES) 'Wessex Electrics' EMUs^▸ (Electric Multiple Unit). The best things running on the third rail in my opinion. They are indeed based on the MkIII design and have powered external plug doors.

[Btline]

By the time you've faffed around with adding plug doors etc. you might as well have built NEW Mark 5 coaches.

Adding yet more to the Mark 3s will just make them unreliable, as this mods keep breaking down. And of course there is the crashworthiness. Yes, they've been pretty good, but we've made advances since then.

[moonrakerz]

But didn't one of the carriages fold in half during the Upton Nervett crash?

Yes.....but.........

"The third coach, which contained the buffet, impacted or was impacted by a loose bogie. This caused severe damage to the underframe in the area of the kitchen, weakening the structure and allowing the body to be bent in plan view through an angle of around 150 degrees."

"It would be impracticable to expect a rail vehicle body to survive ........... impact with such an object without sustaining gross permanent deformation"

From the accident report.

[paul7575]

Surely one of the basic things you have to do to justify the introduction of new stock is to compare the whole life costs of new build with the cost of life extension of the existing stock - and the latter is only over the extension period. Just because DfT^» (Department for Transport - about) have asked for the figures to be worked out it is no guarantee that it will happen, in fact the opposite is just as likely, as far as I can see.

Paul

[IndustryInsider]

But didn't one of the carriages fold in half during the Upton Nervett crash?

Yes.....but.........

"The third coach, which contained the buffet, impacted or was impacted by a loose bogie. This caused severe damage to the underframe in the area of the kitchen, weakening the structure and allowing the body to be bent in plan view through an angle of around 150 degrees."

"It would be impracticable to expect a rail vehicle body to survive ........... impact with such an object without sustaining gross permanent deformation"

Fair enough - I didn't realise it'd been hit by a stray bogie - though it does prompt the question whether a newer and lighter design of bogie (the smaller wheel design as on most modern vehicles) would have caused the same damage to a carriage with a stronger design?

[RailCornwall]

The physical appearance of the stock is poor, most of the coachwork has dents and minor buckles. All the vinyls can't mask that. The thought that the stock will be here in ten years let alone any longer really is offputting.

[smithy]

The physical appearance of the stock is poor, most of the coachwork has dents and minor buckles. All the vinyls can't mask that. The thought that the stock will be here in ten years let alone any longer really is offputting.

the slight buckles as you put it are just ripples in the steel work of which is not major structure just cosmetic,the main structure is beneath this.if you had a car that used such large pieces of steel panel on the exterior then they too would have ripples etc.
also the dents are only of a cosmetic concern and not structural,the best mod they could do to improve crash worthiness and extend life would be to fit overriders at the end of each vehicle to prevent coaches from riding up on each other in event of accident,much like newer stock has.

[Electric train]

The Mk3's coaches are a stressed steel skin welded to the steel frame with a corrugated floor pan and extremely strong form of construction. 

Would a modern coach suffer major structurally failure in similar type of impact as Uffton Nervett, I suspect this is not a type of impact envisaged in the design and build of coaches; also I think the fact that it was a buffet car is irrelevant the construction of the coaches is the same.

[RailCornwall]

Just to clarify I'm not doubting the safety of the rolling stock, just it's poor appearance.

[FlyingDutchman]

If they electrify the Line to Plymouth they could use some of the 225.

Can some one tell me why you could not use the MK4 coach with Class 43.

Guy