Safety of EPB and SUB southern EMUs

[Bikeman78]

I grew up with EPBs and SUBs. The first EPB ran the year before I was born; they were withdrawn when I was 43. I was very fond of them, but some of the shine got knocked off in 1991 when I saw what happened at Cannon Street. The old Fotopic "Control we have a problem" collection of accident photos, now at https://andygibbs.zenfolio.com/f1061579691 has some photos of EPBs and SUBS that opened up like cardboard boxes.

I was actually on an EPB (on the South Central division) on the day of the Cannon Street crash. I didn't find out about it until I got home that evening. It didn't put me off riding on them. It was the only fatal accident in my lifetime. Road accidents were killing 5000 people per year until the early 1990s.

 

[bramling]

I was actually on an EPB (on the South Central division) on the day of the Cannon Street crash. I didn't find out about it until I got home that evening. It didn't put me off riding on them. It was the only fatal accident in my lifetime. Road accidents were killing 5000 people per year until the early 1990s.

Was it not speculated that the Cannon Street accident found a weakness in the vehicle concerned? It is interesting, however, that the 317 which was rough-shunted at Cricklewood before entering service also ended up with some quite serious damage at a vehicle end.

The total demolition of one of the 205 vehicles at Cowden was perhaps the most disturbing, however it was a head-on collision at a fair closing speed so there was always going to be serious damage. Never put me off riding on them though - the chances of being involved in a train crash are minimal.

 

[hexagon789]

Was it not speculated that the Cannon Street accident found a weakness in the vehicle concerned

Weren't some of the underframes recycled from older units?

 

[Journeyman]

Weren't some of the underframes recycled from older units?

Pretty much all the SR design EPBs used underframes and bogies originally built in the 20s and 30s. There were LSWR axle boxes knocking about until the nineties.

 

[Bikeman78]

Was it not speculated that the Cannon Street accident found a weakness in the vehicle concerned? It is interesting, however, that the 317 which was rough-shunted at Cricklewood before entering service also ended up with some quite serious damage at a vehicle end.

The total demolition of one of the 205 vehicles at Cowden was perhaps the most disturbing, however it was a head-on collision at a fair closing speed so there was always going to be serious damage. Never put me off riding on them though - the chances of being involved in a train crash are minimal.

Yes Cowden hit home because I had travelled on 205029 a lot when it ran from Reigate to Tonbridge from 1993 to 1994. Admittedly it was the other unit that got destroyed.

I think the worst one on that website is the Sweet Hill crash. The second train has burrowed under three carriages of the front one, made worse by the fact that the bridge pinned down some of the carriages. Very fortunate that both trains were lightly loaded.

 

[bramling]

Yes Cowden hit home because I had travelled on 205029 a lot when it ran from Reigate to Tonbridge from 1993 to 1994. Admittedly it was the other unit that got destroyed.

I think the worst one on that website is the Sweet Hill crash. The second train has burrowed under three carriages of the front one, made worse by the fact that the bridge pinned down some of the carriages. Very fortunate that both trains were lightly loaded.

Yes Sweet Hill was horrific. The overbridge combined with quite a high impact speed seem to have been the main factors there, in that sense I do wonder if a modern train would actually have fared that much better. Would, for example, it have been a case of the bodywork being crushed rather than torn away?

 

[Taunton]

The total demolition of one of the 205 vehicles at Cowden was perhaps the most disturbing, however it was a head-on collision at a fair closing speed so there was always going to be serious damage. Never put me off riding on them though - the chances of being involved in a train crash are minimal.

My hunch is the Cowden closing speed was not dissimilar to Ladbroke Grove. That led to the complete destruction, end to end, of the relatively new leading 165 car. Fortunately being an early morning outward departure there were not many passengers, and few of those had walked to the front.

Let us not get carried away with diss'ing each generation of stock when something a bit more robust (but not hugely so) comes along each time.

 

[30907]

Weren't some of the underframes recycled from older units?

Yes, but as discussed upthread, the underframes themselves weren't the problem, it was their strength relative to the rest.

 

[bramling]

My hunch is the Cowden closing speed was not dissimilar to Ladbroke Grove. That led to the complete destruction, end to end, of the relatively new leading 165 car. Fortunately being an early morning outward departure there were not many passengers, and few of those had walked to the front.

Let us not get carried away with diss'ing each generation of stock when something a bit more robust (but not hugely so) comes along each time.

Cowden couldn’t have been as fast as Ladbroke Grove. The down train had only just left the station, and the 205s were never the fastest to accelerate. I’d say the down train would have been doing 30-35 mph at the most, up train perhaps 50 mph at the most, that’s before any emergency braking. So it’s hard to see Cowden being any more than 80 mph, and in reality is was probably less than that. Ladbroke Grove ISTR was over 100 mph.

 

[alistairlees]

Cowden couldn’t have been as fast as Ladbroke Grove. The down train had only just left the station, and the 205s were never the fastest to accelerate. I’d say the down train would have been doing 30-35 mph at the most, up train perhaps 50 mph at the most, that’s before any emergency braking. So it’s hard to see Cowden being any more than 80 mph, and in reality is was probably less than that. Ladbroke Grove ISTR was over 100 mph.

The accident investigation report in fact states that the closing speed at Cowden was estimated as being between 55mph and 65mph.

 

[hexagon789]

Yes, but as discussed upthread, the underframes themselves weren't the problem, it was their strength relative to the rest.

They being much more robust than the bodyshell on top?

 

[Bald Rick]

They being much more robust than the bodyshell on top?

Very much so.

 

[HSTEd]

They being much more robust than the bodyshell on top?

Indeed, in essence it turned the underframe of one vehcile into a guillotine blade that could slice through any bodywork that got in it's way.

 

[hexagon789]

Very much so.

Indeed, in essence it turned the underframe of one vehcile into a guillotine blade that could slice through any bodywork that got in it's way.

Hence the overriding and destruction of the coach bodies then.

Presumably then the actual age of the underframes wasn't a contributory factor then?

 

[Dr Hoo]

Hence the overriding and destruction of the coach bodies then.

Presumably then the actual age of the underframes wasn't a contributory factor then?

Correct.

 

[Bikeman78]

Hence the overriding and destruction of the coach bodies then.

Presumably then the actual age of the underframes wasn't a contributory factor then?

Buckeye couplings within the unit would have massively reduced the severity of the collision. A Hastings DEMU hit the blocks at Charing Cross in 1979 with no major damage to the carriages. Having said that, EPBs must have had low speed buffer stop collisions prior to Cannon Street but none that I'm aware of caused the same destruction. There's a 22 minute video on YouTube of the rescue effort filmed by the fire brigade. It's pretty grim. The last person wasn't rescued until midday, having been trapped for 3h15m.

 

[Colin1501]

Well, in fairness, that wasn't a function of EPBs but of compartments generally. It happens that the remaining compartments were in EPBs.

To be even fairer, it was actually a function of the nasty piece of work who carried out the murder, who simply took advantage of the surroundings. You don't abolish dark alleys simply because murders sometimes occur in them.

 

[Islineclear3_1]

I believe buckeyes within each unit were considered at one time and actually trialled on a 2EPB but this increased the overall length meaning that a 10car EPB could not fit at certain platforms, e.g. Cannon Street. Therefore, the idea was abandoned

Could this have prevented Cannon Street? One will never know.

 

[richardsun]

'cup and cone' modification

Just curious, what would this have involved? Different couplers?

 

[Colin1501]

Interesting thread. As others have said above, standards change and improve over time, and when the SUBs and EPBs were introduced, they were an improvement on what had gone before. It would be interesting to see the total figure for fatalities in these units, but this would need to be balanced by the fact that, over their lifetimes, they carried tens of millions - perhaps hundreds of millions - of passengers in complete safety.

 

[Bikeman78]

It would be interesting to see the total figure for fatalities in these units,

The only other big incident I can think of is Lewisham in December 1957. Unit 5766 was only 18 months old at the time.

 

[Islineclear3_1]

The only other big incident I can think of is Lewisham in December 1957. Unit 5766 was only 18 months old at the time.

And written off as a result

 

[edwin_m]

Just curious, what would this have involved? Different couplers?

Primarily an improved anti-climber that would also lock vehicles together laterally in the event of collision, as the cone on one side of the underframe engaged with the cup on the other (so facing) side of the underframe on the next vehicle. But as the idea developed the decided it needed to have the gangways removed, and I think some sort of collapsable coupler too, to ensure that they engaged properly. Ultimately abandoned because the cost was way in excess of the likely safety benefit - in fact if the entire UK passenger fleet had been fitted at the time, I don't think it would have saved a single life up until today.

 

[big all]

The only other big incident I can think of is Lewisham in December 1957. Unit 5766 was only 18 months old at the time.

i think 5766 being a later 57 clasification [1957 stock ]like the BR 4 car epbs had standard depression bar and buckeye coupling in between making the units a few foot longer ??

 

[Dr_Paul]

As others have said above, standards change and improve over time, and when the SUBs and EPBs were introduced, they were an improvement on what had gone before.

For all their faults, the BR Mark I carriages were a great improvement over the previous wooden-bodied carriages. The Mark Is involved in the Harrow and Wealdstone accident fared much better than the older carriages.

 

[hexagon789]

Correct.

So nothing to do with age but really just the design/construction of the body and the multitude of door openings which weakened the structure? I can see why the destruction was so sever then.

Buckeye couplings within the unit would have massively reduced the severity of the collision. A Hastings DEMU hit the blocks at Charing Cross in 1979 with no major damage to the carriages. Having said that, EPBs must have had low speed buffer stop collisions prior to Cannon Street but none that I'm aware of caused the same destruction. There's a 22 minute video on YouTube of the rescue effort filmed by the fire brigade. It's pretty grim. The last person wasn't rescued until midday, having been trapped for 3h15m.

Would it have stopped the body overriding?

 

[edwin_m]

So nothing to do with age but really just the design/construction of the body and the multitude of door openings which weakened the structure? I can see why the destruction was so sever then.


Would it have stopped the body overriding?

Probably not, as the buckeye doesn't offer much resistance to relative vertical movement. Being fitted with buckeyes didn't prevent Mk1s being declared illegal on the main line railway (with limited exceptions) due to their non-integrated construction.

 

[hexagon789]

Probably not, as the buckeye doesn't offer much resistance to relative vertical movement. Being fitted with buckeyes didn't prevent Mk1s being declared illegal on the main line railway (with limited exceptions) due to their non-integrated construction.

Isn't it something like they need a Mk2 bracketing the set or Mk1s at ends must be non-passenger conveying. Something like that

 

[edwin_m]

Isn't it something like they need a Mk2 bracketing the set or Mk1s at ends must be non-passenger conveying. Something like that

I think that's how they justified keeping some charter stock in service.

 

[hexagon789]

I think that's how they justified keeping some charter stock in service.

TPWS probably greatly decreases the risk of an actual collision or at one at significant speed nowadays as well, which always helps