Suppose you’re driving an artic and for whatever reason it starts to go over, is it inevitable it will go over in all circumstances, or is it possible to recover so it doesn’t go over? If so, how does one do that? Steer into it? Steer away from it? Hit the brakes? Hit the accelerator?
It’s something I’ve never put thought into, so I wouldn’t know exactly what to do, but I’d like to know.
Floor it
Failing that, lean the opposite way
Go with the flow. If it’s gunna go it’s gunna go. You can always blame the wind anyway!!
In theory, at least, if you feel the forces building up to such an extent (seat of pants driving, something being untaught) if you have the opportunity and the space to take you can back off a little and try to let it run a little wider than the arc you are currently travelling, unlikely you’ll have enough power, or able to put the power down quickly to accelerate out of it enough because traction on the inside wheel will be getting light anyway.
To a lesser extent if the roll is at a slowish speed, say under 25mph, then with an artic there is likely to be a reasonable angle between the tractor and trailer, which means that the front of the trailer is already starting to pivot on its single point of contact, ie the fifth wheel, so if you were able to straighten the outfit up then the trailer would lose some of that pivoting action.
And now just to go back in time a bit, some vehicles had a separate driver controlled (yes i know, incredible innit, a driver trusted to operate such a device 
) brake for the trailer only, and careful application of the trailer brakes would pull the vehicle back from it most stable point, unlike braking the whole outfit which throws weight forward onto the front of the trailer where that pivot action mentioned in the above sentence is already under way and can exacerbate the situation if braking is too severe.
Some modern trailers already brake autonomously under cornering/roll forces.
Try to feel whats happening down at the road, learn your vehicle how it handles and the limits of adhesion on various surfaces, the noises it makes when it doesn’t like what you’re doing, learn what makes it tick (ie what do all the switches do eg TC/ASR /axle weight transfers, its incredible how many drivers haven’t a clue how to maximise traction at the drive wheels), make sure your fifth wheel is in the right place, try to load evenly so keeping some decent weight on the drive axle, drive by feel and the seat of your pants and the chances of rollovers are extremely slim.
That was a very lucky recovery.
I have survived two , both in rigids and both due to the wind and both in curtainsiders .
Luckily on both occasions I had enough room to put opposite lock on and they came back down .
Seeing a couple of feet of daylight under the back wheels tends to make your bum grip the seat !
On both occasions it was gusts caused by the funnelled wind due to the landscape and tree lines with gaps .
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ezydriver:
Suppose you’re driving an artic and for whatever reason it starts to go over, is it inevitable it will go over in all circumstances, or is it possible to recover so it doesn’t go over? If so, how does one do that? Steer into it? Steer away from it? Hit the brakes? Hit the accelerator?It’s something I’ve never put thought into, so I wouldn’t know exactly what to do, but I’d like to know.
This is an interesting one, I know there is no comparison with todays modern motors and probably not relevant but in my early days with Carrimore trailers (hydraulic vac braking )and the trailer brake (rears) would come on first , this action tended to straighten the outfit up ,I never ever had a jackknife ever which I put down to this system ,wether the system was adjustable or not I do not know. toshboy
Will_161:
https://www.youtube.com/watch?v=kllMekpmy4gThat was a very lucky recovery.
There’s 26 pallets of yoghurts that are no longer 26 pallets of yoghurts lol.
I can’t see what he did to recover… or how that recovered, other than the offside wheels coming down off the high curb in a stroke of luck, or perhaps he steered into it a little, as he appears to go in a straight line for a while.
Juddian:
you can … try to let it run a little wider than the arc you are currently travelling
Can you explain this a little more please. I don’t quite understand what you mean. If you watch the above youtube video, does the Turner’s driver run wider than the arc? I’m assuming because he didn’t carry on around the roundabout and instead ran off in a straight line - off the roundabout - he went wider than the arc. Yes? In effect steering in the same direction as the potential rollover?
I rolled an artic, 44T scrap bulker. Once you see the trailer wheels up in the air in your mirror your buggered, I did it on a roundabout so no way I could turn into it to correct the roll as I would have crashed into a concrete bridge instead. I simply held the wheel as hard as possible and closed my eyes whilst the windscreen and drivers window smashed and anything in the cab not nailed down was flung at me and out the window whilst sliding.
Yes, if you are taking a curve at a speed slightly too high and you realise everything has gone light, then the safest thing to do is try to run a little wider whilst reducing speed as gently as possible, very much the same scenario if you’ve overdone it on a slippery road and, again, there’s that moment when you realise everything has gone light and traction is about to be lost (not good when towing because all sorts of forces come into play), again trying to run lightly wider if there is room whilst reducing the speed is the safest option.
The arc is the compass curve your vehicle is describing at that moment, obviously the wider that curve/arc (the gentler the curve you are making) then the faster it can be taken before things go wrong, so if there is room to make the bend wider that’s the best option IMHO.
Re the video with the Turners lorry, i think that was trailer autonomous braking coming into play which dragged the vehicle back from the back, i suspect had the driver braked normally then the whole lot was going over.
did the turners not hit the roundabout kerb causing it to lift? but id agree it was the trailer autobrake that kept it down.
ive had a couple of instances that ive taken a corner too fast had saw daylight under the wheel and managed to save it,but by the time you see daylight,its mostly good luck as to whether it tips or drops.
They’ll be air under the trailer wheels before you feel anything amiss up the pointy end. Your better off driving at a sensible speed, than trying to recover from an overcooked manoeuvre.
Star down under.:
They’ll be air under the trailer wheels before you feel anything amiss up the pointy end. Your better off driving at a sensible speed, than trying to recover from an overcooked manoeuvre.
Exactly my thoughts. The energy spent trying to prepare to recover from such a serious mistake, would be better spent driving more sedately to begin with.
And if you do feel that you’re about to enter a curve at too high a speed (or you’re about to hit adverse camber or mount a kerb), the best pre-primed reaction would be to go for the footbrake immediately, and if possible ease any turn that you have to make.
On the brake, you could well be stopped dead (or at least back well within a comfortable margin) before you even have to make the fatal turn or before the trailer wheels have even hit the uneven surface, and any loss of forward speed will immediately reduce any lateral forces sustained.
As for those who talk of flooring their way out of a rollover, that seems to me like the ravings of a lunatic! 
I think it was in the late 60’s early 70’s when there was a spate of petrol tanker artic’s rolling over on roundabouts. Wasn’t for going too fast but going too slow. Happened when they were going straight ahead and were loaded, the load would slosh to the right then left then right again as driver left roundabout but had built up so much momentum it pushed the wagon over. Think they call this frequency of motion of how the petrol sloshed in time with the speed of the wagon. There was an article about it years ago.
I do drive sedately, and have never come close to a rollover. But, I’ve seen and heard of low speed rollovers, so I’m being a bit pro-active 
juuuuust in case. Same with front blow outs. Never had one, but like to go over in my mind what to do, and what not to do, just in case. That’s what I like about TNUK, I’ve learnt just as much by reading and asking as I have out on the road.
My cv reads “avid member of TNUK”
Actually no it doesn’t.
Thanks for the replies.
My friends and I once nearly got flattened by an artic on a roundabout. We were sat waiting at the front when to the right a big lorry is steaming towards the roundabout. I think his brakes had failed so he basically just had to try and take the tight roundabout at about 40mph.
Anyway over he went and his trailer squashed the bonnet and engine of my mates car, about 3 feet from death. I was in the back and I guess a little safer. Got 4 grand compo out of it too which was nice.
Star down under.:
They’ll be air under the trailer wheels before you feel anything amiss up the pointy end. Your better off driving at a sensible speed, than trying to recover from an overcooked manoeuvre.
Very sensible answer.
Rjan:
And if you do feel that you’re about to enter a curve at too high a speed (or you’re about to hit adverse camber or mount a kerb), the best pre-primed reaction would be to go for the footbrake immediately, and if possible ease any turn that you have to make.On the brake, you could well be stopped dead (or at least back well within a comfortable margin) before you even have to make the fatal turn or before the trailer wheels have even hit the uneven surface, and any loss of forward speed will immediately reduce any lateral forces sustained.
As for those who talk of flooring their way out of a rollover, that seems to me like the ravings of a lunatic!
You can brake your way out of trouble so long as it’s all still in a straight line on the approach.But don’t try to do it after you’ve turned in because all the previous forward G forces then get transferred into lateral ones.
As for using power to over come roll it only works if it’s got enough power and it helps if it’s a rear engined rigid but definitely don’t try it with an artic. 
That thing will,or at least should,also have a full load of water on board. 
youtube.com/watch?v=vcmcKOugb-o
While what I learned during that type of initiation into the job helped me to keep the evil handling often silly c of g multi lift Clydesdale council wagon I drove on bulk refuse and plant work in my next job the right side up.Not because it had enough power to get itself into,let alone out of,trouble,but because I knew exactly what the wrong steering inputs would do to it at any speed.IE pause at the straight ahead position between changes of lock such as roundabouts to cancel out the pendulum effect. 
remy:
I think it was in the late 60’s early 70’s when there was a spate of petrol tanker artic’s rolling over on roundabouts. Wasn’t for going too fast but going too slow. Happened when they were going straight ahead and were loaded, the load would slosh to the right then left then right again as driver left roundabout but had built up so much momentum it pushed the wagon over. Think they call this frequency of motion of how the petrol sloshed in time with the speed of the wagon. There was an article about it years ago.
I’m not sure it was as long ago as the 70s. More likely the mid 90s when they started to fit dodgy small roundabouts everywhere.
The reason is not strictly going “too slow”. It is going at a speed where the bumps and turns of the roadway happen to resonate with the sloshing of the liquid inside the tank (which depends on allsorts including the viscosity, the profile of the tank, the fill level, the exact timings of brake applications and turns, and so on).
The answer is always to go even slower until they get the jackhammers out and re-engineer the road itself, not to go faster (since going faster is likely to entail other dangers as well as increasing the overall risk of rolling over).
Carryfast:
Rjan:
And if you do feel that you’re about to enter a curve at too high a speed (or you’re about to hit adverse camber or mount a kerb), the best pre-primed reaction would be to go for the footbrake immediately, and if possible ease any turn that you have to make.On the brake, you could well be stopped dead (or at least back well within a comfortable margin) before you even have to make the fatal turn or before the trailer wheels have even hit the uneven surface, and any loss of forward speed will immediately reduce any lateral forces sustained.
As for those who talk of flooring their way out of a rollover, that seems to me like the ravings of a lunatic!
You can brake your way out of trouble so long as it’s all still in a straight line on the approach.But don’t try to do it after you’ve turned in because all the previous forward G forces then get transferred into lateral ones.
Obviously the earlier you catch things the better, and a hard brake application even just milliseconds before a turn, is far better than any fumbling you can manage with the steering once you’re turning.
Also bear in mind, the lateral forces are a product of the forward momentum and the degree of steering input (the vehicle doesn’t move crabwise). Even braking whilst turning, will immediately reduce lateral forces.
As for using power to over come roll it only works if it’s got enough power and it helps if it’s a rear engined rigid but definitely don’t try it with an artic.
A rear-engined rigid? Like a passenger bus?
With most automatic transmissions, once the wheels were up you’d be on your side before the gearbox had found the right gear for maximum power.
I’d stick by the principle that the answer to any perceived rollover risk is to brake as hard as necessary at the earliest opportunity. Whatever else you do, your right foot should be on the footbrake.