Operation "Smash Hit"
Discussion
Dont now why but this came up in conversion the other night, when the CEGB decide to smash a train into a Nuclear waste flask.
It really caught our imagination at the time, my mate Chis and I simulated it on his train set, it was just so dramitic, that bit where it rounds the corner at 100 mph or so, smoking hard and then ploughs into the flask and rides up. Think it was about the coolest thing we had ever seen at 12/13.
Anyone else remember it well or was involved in any way ? Love to hear any further details.
https://en.wikipedia.org/wiki/British_Rail_Class_4...
https://www.youtube.com/watch?v=UOVNTcc-vPw
It really caught our imagination at the time, my mate Chis and I simulated it on his train set, it was just so dramitic, that bit where it rounds the corner at 100 mph or so, smoking hard and then ploughs into the flask and rides up. Think it was about the coolest thing we had ever seen at 12/13.
Anyone else remember it well or was involved in any way ? Love to hear any further details.
https://en.wikipedia.org/wiki/British_Rail_Class_4...
https://www.youtube.com/watch?v=UOVNTcc-vPw
I think at the time there was lots of controversy over the movement of nuclear waste by rail and you even had certain London boroughs declaring themselves nuclear free zones. Quite what authority they had to stop any train movements throughout their borough remained to be seen but I suppose it was a gesture to peace and love, man. 
I suppose this demonstration was to allay public concerns about their safety.
Remember it happening and it was probably the coolest thing I’d seen. They actually drove a loco full pelt into it! Can you imagine them doing it today?
I suppose this demonstration was to allay public concerns about their safety.Remember it happening and it was probably the coolest thing I’d seen. They actually drove a loco full pelt into it! Can you imagine them doing it today?
valiant said:
I suppose this demonstration was to allay public concerns about their safety.
Yes, it was as simple as that.Yet even though it's been proven that nuclear waste can be transported safely, and that nuclear power doesn't emit carbons, the hippies still can't cope with it. Organic llama dung anyone? I mean, that gives off organic CO2, which is OK man... [/neilmode]
We had our offices in the adjacent ex-MOD site for a few years and used to see Tube trains under test on that line, but hadn't realised it was the site of the flask demo until I was looking into the history of the site.
https://en.m.wikipedia.org/wiki/Old_Dalby_Test_Tra...
https://www.railmagazine.com/trains/heritage/it-s-...
https://maps.app.goo.gl/nAksGVSmBoug6ahD6
https://en.m.wikipedia.org/wiki/Old_Dalby_Test_Tra...
https://www.railmagazine.com/trains/heritage/it-s-...
https://maps.app.goo.gl/nAksGVSmBoug6ahD6
Edited by StephenP on Tuesday 22 August 22:48
There was a minor trick played in this test, mainly the choice of the Class 46 Loco. If there are any train buffs reading I'll probably get some detail slightly wrong but hopefully I can explain the gist as it was told to me but a retired member of the BNFL flask transport division in the 1990s.
Firstly 100mph was arbitrary. Nuclear flask trains never travelled that fast. Intercity 125 Class 43 sets had into operation around this era and could be running on routes nuclear flask trains ran. (Very briefly 140mph APTs were also in operation but not known to be frequent on the same rail routes). But that is the fasted train, what about a train with the most momentum. Hmm, a slow but very heavy coal train won't look "sexy" to the viewers, lets have a reasonably fast passenger train that viewers see on their commutes, saves arguing technical details.
Mk1 coaches were used, these were not very strong, Mk3 /4 was the production standard at this point in time. But the sneaky trick was the selection of the Class 46. The Class 46 effectively "sat" on top of its wheel bogies, held down by the weight of the diesel engine, generators etc inside the loco body above the loco buffer height on the loco bedplate. Other locos had more weight lower down and different means of being fixed to the bogie, so this was a preferentially engineered loco - the flask division had spend a couple of years modelling which loco to choose and it was the Class 46 chosen as it was expected to come off its bogies and the heavy part of the loco (engine/genset) ride over and above the top of the flask, leaving the underslung fuel tanks to hit the flask, burst spill fuel everywhere and as the carriages collapse like the matchstick strength they had a nice fire makes everything all so "OMG" and out the other side comes a slightly burnt fuel flask.
The test though did provide a lot of good data for the structural models for nuclear flasks and nuclear containment strength planning. The Americans were also in similar test programmes. They did it one better..........https://interestingengineering.com/innovation/crashed-jet-nuclear-reactor-test
Firstly 100mph was arbitrary. Nuclear flask trains never travelled that fast. Intercity 125 Class 43 sets had into operation around this era and could be running on routes nuclear flask trains ran. (Very briefly 140mph APTs were also in operation but not known to be frequent on the same rail routes). But that is the fasted train, what about a train with the most momentum. Hmm, a slow but very heavy coal train won't look "sexy" to the viewers, lets have a reasonably fast passenger train that viewers see on their commutes, saves arguing technical details.
Mk1 coaches were used, these were not very strong, Mk3 /4 was the production standard at this point in time. But the sneaky trick was the selection of the Class 46. The Class 46 effectively "sat" on top of its wheel bogies, held down by the weight of the diesel engine, generators etc inside the loco body above the loco buffer height on the loco bedplate. Other locos had more weight lower down and different means of being fixed to the bogie, so this was a preferentially engineered loco - the flask division had spend a couple of years modelling which loco to choose and it was the Class 46 chosen as it was expected to come off its bogies and the heavy part of the loco (engine/genset) ride over and above the top of the flask, leaving the underslung fuel tanks to hit the flask, burst spill fuel everywhere and as the carriages collapse like the matchstick strength they had a nice fire makes everything all so "OMG" and out the other side comes a slightly burnt fuel flask.
The test though did provide a lot of good data for the structural models for nuclear flasks and nuclear containment strength planning. The Americans were also in similar test programmes. They did it one better..........https://interestingengineering.com/innovation/crashed-jet-nuclear-reactor-test
Given the other tests the flasks had/have to go through this the train test was much more about showing something visually exciting and reassuring than really testing the strength of the flask.
There have been flasks dropped, damaged etc, during normal operation and not one has ever leaked or become structurally unsafe.
As for new nuclear fuel.... well that simply arrives on the back of a bog standard artic lorry.
There have been flasks dropped, damaged etc, during normal operation and not one has ever leaked or become structurally unsafe.
As for new nuclear fuel.... well that simply arrives on the back of a bog standard artic lorry.
Allegro_Snapon said:
There was a minor trick played in this test, mainly the choice of the Class 46 Loco. If there are any train buffs reading I'll probably get some detail slightly wrong but hopefully I can explain the gist as it was told to me but a retired member of the BNFL flask transport division in the 1990s.
Firstly 100mph was arbitrary. Nuclear flask trains never travelled that fast. Intercity 125 Class 43 sets had into operation around this era and could be running on routes nuclear flask trains ran. (Very briefly 140mph APTs were also in operation but not known to be frequent on the same rail routes). But that is the fasted train, what about a train with the most momentum. Hmm, a slow but very heavy coal train won't look "sexy" to the viewers, lets have a reasonably fast passenger train that viewers see on their commutes, saves arguing technical details.
Mk1 coaches were used, these were not very strong, Mk3 /4 was the production standard at this point in time. But the sneaky trick was the selection of the Class 46. The Class 46 effectively "sat" on top of its wheel bogies, held down by the weight of the diesel engine, generators etc inside the loco body above the loco buffer height on the loco bedplate. Other locos had more weight lower down and different means of being fixed to the bogie, so this was a preferentially engineered loco - the flask division had spend a couple of years modelling which loco to choose and it was the Class 46 chosen as it was expected to come off its bogies and the heavy part of the loco (engine/genset) ride over and above the top of the flask, leaving the underslung fuel tanks to hit the flask, burst spill fuel everywhere and as the carriages collapse like the matchstick strength they had a nice fire makes everything all so "OMG" and out the other side comes a slightly burnt fuel flask.
The test though did provide a lot of good data for the structural models for nuclear flasks and nuclear containment strength planning. The Americans were also in similar test programmes. They did it one better..........https://interestingengineering.com/innovation/crashed-jet-nuclear-reactor-test
I had some colleagues who worked on setting up the test and the locomotive controlsFirstly 100mph was arbitrary. Nuclear flask trains never travelled that fast. Intercity 125 Class 43 sets had into operation around this era and could be running on routes nuclear flask trains ran. (Very briefly 140mph APTs were also in operation but not known to be frequent on the same rail routes). But that is the fasted train, what about a train with the most momentum. Hmm, a slow but very heavy coal train won't look "sexy" to the viewers, lets have a reasonably fast passenger train that viewers see on their commutes, saves arguing technical details.
Mk1 coaches were used, these were not very strong, Mk3 /4 was the production standard at this point in time. But the sneaky trick was the selection of the Class 46. The Class 46 effectively "sat" on top of its wheel bogies, held down by the weight of the diesel engine, generators etc inside the loco body above the loco buffer height on the loco bedplate. Other locos had more weight lower down and different means of being fixed to the bogie, so this was a preferentially engineered loco - the flask division had spend a couple of years modelling which loco to choose and it was the Class 46 chosen as it was expected to come off its bogies and the heavy part of the loco (engine/genset) ride over and above the top of the flask, leaving the underslung fuel tanks to hit the flask, burst spill fuel everywhere and as the carriages collapse like the matchstick strength they had a nice fire makes everything all so "OMG" and out the other side comes a slightly burnt fuel flask.
The test though did provide a lot of good data for the structural models for nuclear flasks and nuclear containment strength planning. The Americans were also in similar test programmes. They did it one better..........https://interestingengineering.com/innovation/crashed-jet-nuclear-reactor-test
The Class 45/46s had plenty of weight low, one bogie was more than half the weight of a HST power car at around 40t. I remember them from my training, big heavy and underpowered and more importantly - no-one wanted them. Overall these locos were 20t heavier than anything else British Rail had.
With a concrete flask it is the initial impact that is likely to crack it, once it is moving you just push it along.
I do remember seeing collision damaged class 56s in Doncaster, 2" thick steel plate bent as if it was paper.
Edited by IJWS15 on Thursday 24th August 15:09
IJWS15 said:
Allegro_Snapon said:
There was a minor trick played in this test, mainly the choice of the Class 46 Loco. If there are any train buffs reading I'll probably get some detail slightly wrong but hopefully I can explain the gist as it was told to me but a retired member of the BNFL flask transport division in the 1990s.
Firstly 100mph was arbitrary. Nuclear flask trains never travelled that fast. Intercity 125 Class 43 sets had into operation around this era and could be running on routes nuclear flask trains ran. (Very briefly 140mph APTs were also in operation but not known to be frequent on the same rail routes). But that is the fasted train, what about a train with the most momentum. Hmm, a slow but very heavy coal train won't look "sexy" to the viewers, lets have a reasonably fast passenger train that viewers see on their commutes, saves arguing technical details.
Mk1 coaches were used, these were not very strong, Mk3 /4 was the production standard at this point in time. But the sneaky trick was the selection of the Class 46. The Class 46 effectively "sat" on top of its wheel bogies, held down by the weight of the diesel engine, generators etc inside the loco body above the loco buffer height on the loco bedplate. Other locos had more weight lower down and different means of being fixed to the bogie, so this was a preferentially engineered loco - the flask division had spend a couple of years modelling which loco to choose and it was the Class 46 chosen as it was expected to come off its bogies and the heavy part of the loco (engine/genset) ride over and above the top of the flask, leaving the underslung fuel tanks to hit the flask, burst spill fuel everywhere and as the carriages collapse like the matchstick strength they had a nice fire makes everything all so "OMG" and out the other side comes a slightly burnt fuel flask.
The test though did provide a lot of good data for the structural models for nuclear flasks and nuclear containment strength planning. The Americans were also in similar test programmes. They did it one better..........https://interestingengineering.com/innovation/crashed-jet-nuclear-reactor-test
I had some colleagues who worked on setting up the test and the locomotive controlsFirstly 100mph was arbitrary. Nuclear flask trains never travelled that fast. Intercity 125 Class 43 sets had into operation around this era and could be running on routes nuclear flask trains ran. (Very briefly 140mph APTs were also in operation but not known to be frequent on the same rail routes). But that is the fasted train, what about a train with the most momentum. Hmm, a slow but very heavy coal train won't look "sexy" to the viewers, lets have a reasonably fast passenger train that viewers see on their commutes, saves arguing technical details.
Mk1 coaches were used, these were not very strong, Mk3 /4 was the production standard at this point in time. But the sneaky trick was the selection of the Class 46. The Class 46 effectively "sat" on top of its wheel bogies, held down by the weight of the diesel engine, generators etc inside the loco body above the loco buffer height on the loco bedplate. Other locos had more weight lower down and different means of being fixed to the bogie, so this was a preferentially engineered loco - the flask division had spend a couple of years modelling which loco to choose and it was the Class 46 chosen as it was expected to come off its bogies and the heavy part of the loco (engine/genset) ride over and above the top of the flask, leaving the underslung fuel tanks to hit the flask, burst spill fuel everywhere and as the carriages collapse like the matchstick strength they had a nice fire makes everything all so "OMG" and out the other side comes a slightly burnt fuel flask.
The test though did provide a lot of good data for the structural models for nuclear flasks and nuclear containment strength planning. The Americans were also in similar test programmes. They did it one better..........https://interestingengineering.com/innovation/crashed-jet-nuclear-reactor-test
The Class 45/46s had plenty of weight low, one bogie was more than half the weight of a HST power car at around 40t. I remember them from my training, big heavy and underpowered and more importantly - no-one wanted them. Overall these locos were 20t heavier than anything else British Rail had.
With a concrete flask it is the initial impact that is likely to crack it, once it is moving you just push it along.
I do remember seeing collision damaged class 56s in Doncaster, 2" thick steel plate bent as if it was paper.
Edited by IJWS15 on Thursday 24th August 15:09
Was it a concrete flask? I though the fuel flasks were steel, the waste flasks used internally on site being concrete boxes.
Mind the transports that used to scare me were the UF6 Preston to Chester Tankers that used the M6/M56.
Of course flasks are only as good as designed, forget to put the seal in and only by the shine path pointing downwards was not more harm done....https://www.thetelegraphandargus.co.uk/news/8087316.lorry-leaked-radiation-as-it-passed-through-wharfedale/
I worked for British Rail Research at the time, in the section that studied derailments and predicted risks arising, and also that liaised between the brilliant, but sometimes slightly unworldly denizens of BRR and the "real" operating railway.
The Central Electricity Generating Board (CEGB) commissioned this test, with assistance from the international consultants Ove Arup and Partners (Arup). My job was to handle the liaison with the many parties, from real railway Mechanical, and Civil Engineers, through railway operating departments, Transport Police, the local Fire Brigade, adjoining landowners, film crews, site security, BT (no mobiles in 1984!) and even a tea van. CEGB wanted to bring their guests to the site by trains, and to make sure no flying debris landed in the stands we had built.
The purpose of the crash test evolved over time, from a scientific validation of the modelling of a worst-realistic collision, to a PR exercise, timed to be shown live on lunchtime news broadcasts. The role of BRR was a neutral provider of a loud bang: we had no supplementary studies, and CEGB designed the details of the test.
It would take a book to cover all the decisions made, but to address some of the points mentioned:
We did not have a free choice of loco: CEGB were rightly keen on the magic 100 mph as a target, and did not want to pay for a loco with many years of service left in it. The Class 46 was structurally identical to the 45, many of which were still in mainline use at 90 mph, and two units could be released. The good men at Toton were familiar with them, and knew just how far everything could be tweaked. Two locos? yes 46009 as the first choice, and 46023, with a spare set of coaches, sat it out at Edwalton, at the north end of the test track - just in case. Why only three coaches? Because any more would have meant accepting a drop in the achieved speed. Three was enough to look like a passenger train, but if you watch the video, you'll see the real collision is over long before the third coach starts getting damaged.
And no, neither the coaches nor the locos were lightened, weighted down, or modified beyond the minimum needed for safe remote starting and stopping. A Greenpeace loony claimed afterwards that we had removed all the engine mounting bolts, but did have the grace to apologise at the subsequent IMechE conference when I showed one such bolt to the delegates and threatened to ram it where the sun doesn't shine if he ever again impugned to integrity of the BR engineers involved.
There's been some woolly thinking about the business of the design of the impact. We were told to position the new, instrumented flask on a new, instrumented flask wagon, in the position that would maximise the risk of damage. Thus, 45 degrees to the track centreline, with the loco drawhook hitting the joint between flask lid and body, as if to wedge it open. An interesting task for the Toton crane, but they did it.
I'll happily try to answer any questions that arise, to the extent that 39 years ago permits, but I will admit to one cockup: the locos had to be fuelled up at Toton before positioning for the test. We carefully worked out how much fuel would cover delays getting to Melton, delays caused by outsiders (like the BBC cameramen allowing protesters over the security fence), and delays if we'd needed to abort then re-run the test. And everyone involved thought they'd help by adding a bit more - hence the rather spectacular whoosh.
Sorry about the length of this - wait till I go on about the contingency plans for this test, and the two other tests we also designed and evaluated, but which we didn't need to do.
Best day of my railway career.
The Central Electricity Generating Board (CEGB) commissioned this test, with assistance from the international consultants Ove Arup and Partners (Arup). My job was to handle the liaison with the many parties, from real railway Mechanical, and Civil Engineers, through railway operating departments, Transport Police, the local Fire Brigade, adjoining landowners, film crews, site security, BT (no mobiles in 1984!) and even a tea van. CEGB wanted to bring their guests to the site by trains, and to make sure no flying debris landed in the stands we had built.
The purpose of the crash test evolved over time, from a scientific validation of the modelling of a worst-realistic collision, to a PR exercise, timed to be shown live on lunchtime news broadcasts. The role of BRR was a neutral provider of a loud bang: we had no supplementary studies, and CEGB designed the details of the test.
It would take a book to cover all the decisions made, but to address some of the points mentioned:
We did not have a free choice of loco: CEGB were rightly keen on the magic 100 mph as a target, and did not want to pay for a loco with many years of service left in it. The Class 46 was structurally identical to the 45, many of which were still in mainline use at 90 mph, and two units could be released. The good men at Toton were familiar with them, and knew just how far everything could be tweaked. Two locos? yes 46009 as the first choice, and 46023, with a spare set of coaches, sat it out at Edwalton, at the north end of the test track - just in case. Why only three coaches? Because any more would have meant accepting a drop in the achieved speed. Three was enough to look like a passenger train, but if you watch the video, you'll see the real collision is over long before the third coach starts getting damaged.
And no, neither the coaches nor the locos were lightened, weighted down, or modified beyond the minimum needed for safe remote starting and stopping. A Greenpeace loony claimed afterwards that we had removed all the engine mounting bolts, but did have the grace to apologise at the subsequent IMechE conference when I showed one such bolt to the delegates and threatened to ram it where the sun doesn't shine if he ever again impugned to integrity of the BR engineers involved.
There's been some woolly thinking about the business of the design of the impact. We were told to position the new, instrumented flask on a new, instrumented flask wagon, in the position that would maximise the risk of damage. Thus, 45 degrees to the track centreline, with the loco drawhook hitting the joint between flask lid and body, as if to wedge it open. An interesting task for the Toton crane, but they did it.
I'll happily try to answer any questions that arise, to the extent that 39 years ago permits, but I will admit to one cockup: the locos had to be fuelled up at Toton before positioning for the test. We carefully worked out how much fuel would cover delays getting to Melton, delays caused by outsiders (like the BBC cameramen allowing protesters over the security fence), and delays if we'd needed to abort then re-run the test. And everyone involved thought they'd help by adding a bit more - hence the rather spectacular whoosh.
Sorry about the length of this - wait till I go on about the contingency plans for this test, and the two other tests we also designed and evaluated, but which we didn't need to do.
Best day of my railway career.
Yertis said:
Well come on then! You can’t leave us hanging like that! 
Indeed! It's amazing, the people and knowledge that pops up on PH! I've read a few stories of how the loco was set in motion at the start of the run but would love to hear it from an expert with first hand knowledge!
I remember this. I was 15 or 16 at the time and didn't really understand the significance of it but totally enjoyed the spectacle.
Sometime in the mid-1990s I worked (in IT) for Alstom who had a presence at the Dalby line, where I worked for a few days, including inside a moving carriage on the line. We were working on data transmission from moving carriages to a fixed station. Even then, I didn't realise I was on "that" line.
In the late-1990s I worked (again, in IT) at 3 different Magnox power stations including Oldbury/Thornbury where there was a training centre, and the guys there explained the significance of the Dalby test to me (and I got a detailed assessment of the Chernobyl disaster from them too). I felt hugely privileged to listen to one particular chap who was kind enough to spend the time explaining it to me and my colleagues.
Sometime in the mid-1990s I worked (in IT) for Alstom who had a presence at the Dalby line, where I worked for a few days, including inside a moving carriage on the line. We were working on data transmission from moving carriages to a fixed station. Even then, I didn't realise I was on "that" line.
In the late-1990s I worked (again, in IT) at 3 different Magnox power stations including Oldbury/Thornbury where there was a training centre, and the guys there explained the significance of the Dalby test to me (and I got a detailed assessment of the Chernobyl disaster from them too). I felt hugely privileged to listen to one particular chap who was kind enough to spend the time explaining it to me and my colleagues.
The essential fact behind consideration of this "driverless" train is that the loco's own control system is really rather clever. You do not need to apply power gently, or in a careful, controlled manner. If you bang the power controller straight round to full power, it just goes, and the loco takes care of all the field weakening and such like. The result, on the 20 or so proving runs we did in the months before the big day, was a remarkable consistency of performance for a given starting point and train formation. Some of the drivers on these proving runs almost needed tying down to be so brutish - they'd started on steam, many of them, where that's not how you drive.
Although almost everyone in BRR (being clever people) wanted to devise elaborate control systems, we resisted firmly. Toton TMD fitted a Tee into the loco air brake pipe, and mounted a manual cock at about solebar level near the cab. **** Next bit was over simplified in my post**** I've now attached an extract from one of the papers presented to an I Mech E conference, published as ISBN 0 85298 574 6. This extract describes the system as it had been slightly tweaked for the day. The fitter who did this then climbed down from the cab, and on final confirmation, closed the air cock and dropped a switch. Pressure built up, the brakes came off, and power came on. Bye bye train.
This system readily covered some of the contingencies. BT Police were genuinely concerned about a spectacular protest - say someone lying down on the track, or sabotage. We couldn't guard 8 miles of track against loonies, so the reasonable compromise was to set up two "abort points", equipped with AWS magnets, as used at the time to apply the brakes if trains passed signals at danger. BRR staff had to override these electromagnets if the test controller confirmed all was still well as the train approached. They also had radar speed guns, so if there had been a fault reducing the train's performance, they were to let the train be brought to a stand by the AWS system. Another compromise: if the second abort point had been too near the crash location, there was a risk the visitors would have seen the train come into view, brakes smoking, and then gently nuzzle the flask, and we would have felt prats. We also had to have a clear plan how to re-run the test after, say, drawing a failed train back to Edwalton, shunting locos or coaches (knocking out a cripple, as you could call it in those far-off days).
Plenty more where this came from, if anyone's still reading.
Kevin
Although almost everyone in BRR (being clever people) wanted to devise elaborate control systems, we resisted firmly. Toton TMD fitted a Tee into the loco air brake pipe, and mounted a manual cock at about solebar level near the cab. **** Next bit was over simplified in my post**** I've now attached an extract from one of the papers presented to an I Mech E conference, published as ISBN 0 85298 574 6. This extract describes the system as it had been slightly tweaked for the day. The fitter who did this then climbed down from the cab, and on final confirmation, closed the air cock and dropped a switch. Pressure built up, the brakes came off, and power came on. Bye bye train.
This system readily covered some of the contingencies. BT Police were genuinely concerned about a spectacular protest - say someone lying down on the track, or sabotage. We couldn't guard 8 miles of track against loonies, so the reasonable compromise was to set up two "abort points", equipped with AWS magnets, as used at the time to apply the brakes if trains passed signals at danger. BRR staff had to override these electromagnets if the test controller confirmed all was still well as the train approached. They also had radar speed guns, so if there had been a fault reducing the train's performance, they were to let the train be brought to a stand by the AWS system. Another compromise: if the second abort point had been too near the crash location, there was a risk the visitors would have seen the train come into view, brakes smoking, and then gently nuzzle the flask, and we would have felt prats. We also had to have a clear plan how to re-run the test after, say, drawing a failed train back to Edwalton, shunting locos or coaches (knocking out a cripple, as you could call it in those far-off days).
Plenty more where this came from, if anyone's still reading.
Kevin
Edited by Autolycus on Saturday 26th August 12:53
Edited by Autolycus on Saturday 26th August 19:57
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