HST derailment, near Stonehaven, 12th August 2020

[whole diary]

[bradshaw]

Given the report’s concerns on the HSTs^▸ (High Speed Train) the plans of GWR^▸ (Great Western Railway) to replace them with IETs^▸ (Intercity Express Train) seems to be a sound judgement.
Note that a risk assessment has to be carried out on the HST relating to their further use and to ALL pre-1994 rolling stock(the date that the crashworthiness standards came in. That covers all the 15x series, 165 and 166. This might have implications for the GWR and the WoE lines 159s.

[paul7575]

Given the report’s concerns on the HSTs^▸ (High Speed Train) the plans of GWR^▸ (Great Western Railway) to replace them with IETs^▸ (Intercity Express Train) seems to be a sound judgement.
Note that a risk assessment has to be carried out on the HST relating to their further use and to ALL pre-1994 rolling stock(the date that the crashworthiness standards came in. That covers all the 15x series, 165 and 166. This might have implications for the GWR and the WoE lines 159s.

Presumably the Sleeper coaches are Mk3 and have the same issue of unsecured bogies?  (The context being that restrained bogies can dig into the ballast and decelerate the coaches.)

[eightonedee]

Bradshaw's comments above would also apply to the 769s which use 1980s class 319 bodyshells too.

[stuving]

Bradshaw's comments above would also apply to the 769s which use 1980s class 319 bodyshells too.

Indeed, when the 319s were stripped to modify them to add the motor/generators, many were found to have serious rust in the sole bars. That's the main lengthwise structural member of the body, so they had to be patched up by welding. No doubt other types approaching their age will also have corrosion if you can get in to find it.

Switching to aluminium alloy won't necessarily help, as their Achilles' metallurgical process is fatigue cracking. That too can be hard to spot, and needs good access to check for it. In both cases you first need to know you have to look for something, of course.

[onthecushions]

I seem to remember the crash-worthiness of the Mark 3's being highly praised after Bushey, Morpeth etc. The identification of a further marginal improvement is no argument for premature scrappimg, which only leads to less rolling stock, fewer train seat miles, more road journeys and more travel deaths.

I am surprised that thorough inspection of vehicle body condition (as in MoT tests!) is not done, or provided for in design and construction, either by access viewing or "oil rig" coatings.

Weren't the Mark 3's built out of "Corten", BSC's higher tensile, lower corrosion steel?

The drain design owed more to a rigid design spec than common sense. Every drain will overflow and gravity must win, so let it!

OTC

[Electric train]

I seem to remember the crash-worthiness of the Mark 3's being highly praised after Bushey, Morpeth etc. The identification of a further marginal improvement is no argument for premature scrappimg, which only leads to less rolling stock, fewer train seat miles, more road journeys and more travel deaths.

I am surprised that thorough inspection of vehicle body condition (as in MoT tests!) is not done, or provided for in design and construction, either by access viewing or "oil rig" coatings.

Weren't the Mark 3's built out of "Corten", BSC's higher tensile, lower corrosion steel?

The drain design owed more to a rigid design spec than common sense. Every drain will overflow and gravity must win, so let it!

OTC

The weakness of the HST^▸ (High Speed Train) Mk3 is the inter vehicle coupling.  Mk3 use buckeye type of couplings which loose attachment in the event of a severe vertical movement, which looks like the case in this accident. 

I think what RAIB^▸ (Rail Accident Investigation Branch) were questioning had a full risk assessment been carried out for the change of how the trains were configured.

The part that is damming is the signing off of contractors work and the control of CDM^▸ (Construction (Design & Management) Regulations) Health and Safety File.  One of the major failing of the current contract arrangements is the contractor has received 90% of the contract payments when a project is commissioned. 

Both NR^» (Network Rail - home page) and the contractors project teams have often moved onto other projects after the commissioning happens so the project close out process along with as built drawings, operation and maintenance manuals can take years to get back to the NR Asset Manager and Maintainer.   Part of this hand back process in to place the asset into the Asset Maintenance system if hand back does not happen assets get left out of the system.

[broadgage]

I can not support the withdrawal of HSTs^▸ (High Speed Train) simply because a newer and safer alternative is available.
Fatal accidents are extremely rare, Stonehaven was the first for many years.

Apart from my personal preferences, rail travel is demonstrably very much safer than driving. Any reduction in rail capacity, or downgrading of comfort and facilities on trains will drive people away from very safe trains and into much less safe cars.

I am aware of people who would take the train, but who choose to drive because the trains are overcrowded, uncomfortable, or hugely expensive.

Despite all the above, I fear that HSTs will be withdrawn from general use. The Stonehaven accident is a splendid excuse to reduce capacity by withdrawing serviceable trains, and to downgrade from inter city trains to types more suited for local services.

[ellendune]

It depends what corrosion criteria they come up with.  If they do a proper assessment on that it could lead to more being scrapped. 

[onthecushions]

I can't quite get my head around the concept that the fixed head, Alliance "Buckeye" coupling used within  many sets is suddenly unsafe. Accidents are rare and so are coupling breaks.

I accept that the MU^▸ (Multiple Unit) future is Dellner and Tightlock, but at the ends of new stock. Could anything survive a high speed derailment on a curve? If a replacement is really sought would not the in-set bar coupler suffice?

OTC

[stuving]

I can't quite get my head around the concept that the fixed head, Alliance "Buckeye" coupling used within  many sets is suddenly unsafe. Accidents are rare and so are coupling breaks.

I accept that the MU^▸ (Multiple Unit) future is Dellner and Tightlock, but at the ends of new stock. Could anything survive a high speed derailment on a curve? If a replacement is really sought would not the in-set bar coupler suffice?

OTC

I know what you mean. I can remember it being said that Buckeye couplings had kept derailed trains largely upright, in particular after Morpeth Curve - where that is debatable. But the report is rather confused on this subject.

It does identify the couplings as more likely to break than those on newer trains, but the main advantage it gives is the prevention of overriding. That seems fair enough: if there are large longitudinal forces between vehicles, they are less destructive if the vehicles stay in line.

As to whether keeping the vehicles attached in a string as they start to concertina is a good idea, they suggest it is. Paragraph 533 directly addresses this question, in the context of the leading power car running off the bridge. They conclude that on balance staying coupled would have limited the power car's deviation off line so it would probably crossed the bridge before leaving the formation. I can't see that, myself.

Thus their conclusion is that couplings that stayed intact would have given a better outcome in this accident. Probably. But accidents vary greatly, and the part played by collisions with solid objects in derailments might be secondary or dominant. If you design a coupling to collapse, then break, at force levels you have chosen, I can't help feeling that the first accident that happens will be the one that proves you chose the wrong values! Like Neville Hill, for example.

[JayMac]

Had the leading power car remained attached to the rest of the train then I can see the possibility of the impact forces after coming off the bridge being lessened. It would have had 200 odd tonnes of train still attached to it, slowing it, anchoring it. With it still attached and no overriding, damage to the leading vestibule area of Coach D may also have been lessened.

Whether that would have prevented the fatal injuries to the conductor and driver from secondary impacts is of course impossible to know.

On the issue of the future of HSTs^▸ (High Speed Train), nostalgia and potential stock shortages should not come before safety.

[Mark A]

Punches are not pulled in the accompanying article:

"The HST^▸ (High Speed Train) cab is essentially an upturned bath tub mounted facing outwards with a driver inside it.

"There is zero crash structure for the cab – absolutely zero crashworthiness whatsoever.

"Zero protection for the driver.

"All there is the base of the front of the HST with a fibreglass shell over the front.


"There is no crash structure at all."

The 'Upturned bathtub' analogy seems to have gained traction but I'm surprised that it's made it into print. Next, it'll be said that the HST windscreen is a standard domestic double glazing unit.

While I'd wish the experience on no member of railway staff: it's worth revisiting the RAIB^▸ (Rail Accident Investigation Branch) report on the July 10th 2010 Lavington accident. (Ash tree vs HST cab at 90 miles an hour).

https://assets.publishing.service.gov.uk/media/547c8feced915d4c10000159/R082011_110407_Lavington.pdf

[broadgage]

My understanding is that the cab of an HST^▸ (High Speed Train) is of substantial construction, but ONLY UP TO THE HEIGHT OF THE CONTROLS. Advice, whether official or otherwise, was to duck or crouch down if accident was imminent.

In the Lavington accident, the driver did this and escaped with only slight injuries, a broken wrist and numerous minor cuts IIRC^▸ (if I recall/remember/read correctly). The damage suggested that remaining seated could have had very serious consequences.

[IndustryInsider]

I can not support the withdrawal of HSTs^▸ (High Speed Train) simply because a newer and safer alternative is available.
Fatal accidents are extremely rare, Stonehaven was the first for many years.

The trouble is of course, should an extremely rare accident happen again, and recommendations have been made to retire the fleet ASAP or instigate very expensive examinations and repairs on a very old fleet, if you're the one who made the decision that said 'Disregard those recommendations, it's highly unlikely to happen again' then you'll have some extremely difficult questions to answer.  So I can understand nervousness...even if I agree with you in principle.

Advice, whether official or otherwise, was to duck or crouch down if accident was imminent.

The unofficial advice was to leg it as far as you could into the clean air compartment behind the cab and lie on the floor!

[broadgage]

I would go as far as to say that "nostalgia and stock shortages" SHOULD override safety, provided of course that the risk to safety is very small as appears to be the case.

Rail travel is very safe, and HSTs^▸ (High Speed Train) have a reasonable safety record if considering the numbers in use and the huge mileages covered, often at high speeds.
I would be happy to travel in an HST even if something newer, shorter, and less comfortable is slightly safer.
I would be happy to drive an HST, after proper training of course.

The safest train is one that never leaves the depot.
The next safest is probably one limited to low speeds, and with only backwards facing seats, all with seatbelts. No food or drink of course, and luggage to be checked in and conveyed in a dedicated area as on aircraft.

Or we could all stay at home, though that carries risks.